The document summarizes the history and developments of the Wolff-Kishner reduction reaction. It describes how Nikolai Kizhner and Ludwig Wolff independently discovered the reaction in 1912 for carbonyl deoxygenation. Over time, various modifications were made to reduce harsh reaction conditions and improve yields, including those by Huang-Minlon, Barton, Nagata, Henbest, Cram, and Caglioti. The reaction mechanism was investigated and both ionic and free radical pathways were proposed. The Wolff-Kishner reduction has been applied in natural product synthesis and the development of new one-step alcohol deoxygenation methods continues to be an area of active research.
Complexes of m(ii)sulphates with 4 cyanobenzaldehyde andAlexander Decker
This document describes the synthesis and characterization of ten complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) sulphates with two organic ligands, 4-cynobenzaldehydecyclopropanecarboxylicacidhydrazone (CBHN) and 4-ethylbenzaldehydecyclopropanecarboxylicacidhydrazones (EBHN). The complexes were characterized using techniques such as melting point determination, IR spectroscopy, elemental analysis, molar conductivity measurements, and electronic spectroscopy. IR data showed that the ligands coordinate to the metal ions through the carbonyl oxygen and azomethine nitrogen. Electronic spectra indicate octahedral geometry for most complexes
B.Sc. (Sem-II) Unit-III (A) Alkenyl Halides by Dr Pramod R Padolepramod padole
This document discusses alkenyl halides, specifically vinyl chloride and allyl chloride. It provides methods of preparation of vinyl chloride from acetylene and of allyl chloride from propylene. It also describes the chemical reactions of vinyl chloride and allyl chloride with aqueous and alcoholic KOH. Allyl chloride is more reactive than vinyl chloride due to the percentage of s-character in the C-Cl bond, stabilization of the allyl carbocation by resonance, and double bond character in the C-Cl bond of vinyl chloride.
B. Sc. Part - I (Sem-II) Unit-IV (A) Phenols by Dr Pramod R Padolepramod padole
A) PHENOLS: Methods of formations a) from aniline & b) from cumene. Acidic character, Reaction of Phenols- a) Carboxylation (Kolbe’s reaction), b) Fries Rearrangement, c) Claisen Rearrengement and d) Reimer – Tiemann reaction.
B.Sc. Sem-II Unit-III (B) Aryl halides by Dr Pramod R Padolepramod padole
The document discusses aryl halides, specifically benzyl chloride and chlorobenzene. It provides methods of synthesizing benzyl chloride from toluene and benzyl alcohol, and discusses its reactions with aqueous KOH, NH3, and sodium ethoxide. It also discusses synthesizing chlorobenzene from benzene, phenol, and benzene diazonium chloride, and the reactions of chlorobenzene with aqueous NaOH, NH3, and sodium ethoxide. The document aims to teach undergraduate chemistry students about the properties and reactions of aryl halides.
Complexes of m(ii)sulphates with 4 cyanobenzaldehyde andAlexander Decker
This document describes the synthesis and characterization of ten complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) sulphates with two organic ligands, 4-cynobenzaldehydecyclopropanecarboxylicacidhydrazone (CBHN) and 4-ethylbenzaldehydecyclopropanecarboxylicacidhydrazones (EBHN). The complexes were characterized using techniques such as melting point determination, IR spectroscopy, elemental analysis, molar conductivity measurements, and electronic spectroscopy. IR data showed that the ligands coordinate to the metal ions through the carbonyl oxygen and azomethine nitrogen. Electronic spectra indicate octahedral geometry for most complexes
B.Sc. (Sem-II) Unit-III (A) Alkenyl Halides by Dr Pramod R Padolepramod padole
This document discusses alkenyl halides, specifically vinyl chloride and allyl chloride. It provides methods of preparation of vinyl chloride from acetylene and of allyl chloride from propylene. It also describes the chemical reactions of vinyl chloride and allyl chloride with aqueous and alcoholic KOH. Allyl chloride is more reactive than vinyl chloride due to the percentage of s-character in the C-Cl bond, stabilization of the allyl carbocation by resonance, and double bond character in the C-Cl bond of vinyl chloride.
B. Sc. Part - I (Sem-II) Unit-IV (A) Phenols by Dr Pramod R Padolepramod padole
A) PHENOLS: Methods of formations a) from aniline & b) from cumene. Acidic character, Reaction of Phenols- a) Carboxylation (Kolbe’s reaction), b) Fries Rearrangement, c) Claisen Rearrengement and d) Reimer – Tiemann reaction.
B.Sc. Sem-II Unit-III (B) Aryl halides by Dr Pramod R Padolepramod padole
The document discusses aryl halides, specifically benzyl chloride and chlorobenzene. It provides methods of synthesizing benzyl chloride from toluene and benzyl alcohol, and discusses its reactions with aqueous KOH, NH3, and sodium ethoxide. It also discusses synthesizing chlorobenzene from benzene, phenol, and benzene diazonium chloride, and the reactions of chlorobenzene with aqueous NaOH, NH3, and sodium ethoxide. The document aims to teach undergraduate chemistry students about the properties and reactions of aryl halides.
IMPORTANT NAMED REACTIONS in Organic synthesis with Introduction, General Mechanism, and their synthetic application covering more than 20 named reactions in it.
The benzoin addition is an addition reaction involving two aldehydes. The reaction generally occurs between aromatic aldehydes or glyoxals. The reaction produces an acyloin. In the classic application benzaldehyde is converted to benzoin
This document summarizes a study that investigated the degradation of halogenated organic compounds (haloorganics) by iron porphyrin complexes as biomimetic models of marine microbial pathways. The study reacted various iodinated substrates with different iron porphyrin complexes and monitored the reactions using UV-Vis spectroscopy and gas chromatography-mass spectrometry. The results showed that the iodo substrates reacted fastest, followed by chloro and bromo substrates. Products identified included methane, ethylene, and the corresponding dehalogenated alkene. Reaction rates correlated with the redox potential of the iron complex, with higher redox potentials corresponding to faster rates. The study provides insights into abiotic marine degradation of haloorgan
Diel's-Alder and Gattermann Koch ReactionsPRUTHVIRAJ K
n organic chemistry, the Diels–Alder reaction is a chemical reaction between a conjugated diene and a substituted alkene, commonly termed the dienophile, to form a substituted cyclohexene derivative. It is the prototypical example of a pericyclic reaction with a concerted mechanism
The Chichibabin reaction is a method for producing 2-aminopyridine derivatives by the reaction of pyridine with sodium amide. It was reported by Aleksei Chichibabin in 1914. The following is the overall form of the general reaction: The direct amination of pyridine with sodium amide takes place in liquid ammonia
This document provides information about carboxylic acids and carboxylic acid derivatives (esters). It discusses the properties, structures, nomenclature, preparation methods, and reactions of carboxylic acids and esters. Key points include:
- Carboxylic acids contain a carboxyl group consisting of a carbonyl and hydroxyl group attached to the same carbon. They have higher boiling points than similar molecules due to hydrogen bonding.
- Esters are carboxylic acid derivatives where the hydroxyl hydrogen is replaced by an alkyl or aryl group. They have pleasant aromas and are slightly soluble in water.
- Carboxylic acids and esters undergo acid-base reactions, esterification,
CBSE Class 12 Chemistry Chapter 10 (Haloalkanes and Haloarenes) | Homi InstituteHomi Institute
Haloalkanes and haloarenes are formed by the replacement of hydrogen atoms in hydrocarbons by halogen atoms. Haloalkanes contain halogen atoms attached to sp3 hybridized carbon atoms of an alkyl group, while haloarenes contain halogen atoms attached to sp2 hybridized carbon atoms of an aryl group. These compounds find wide applications in industry and medicine as solvents, starting materials for synthesis, and components of drugs like chloroquine and halothane. They can be prepared from alcohols, hydrocarbons, and other precursors using various reactions.
The Arndt-Eistert reaction involves the homologation of carboxylic acids through a three step process:
1) Conversion of the acid to the corresponding acid chloride
2) Formation of an α-diazomethyl ketone through reaction with diazomethane
3) Decomposition of the diazoketone, often using a silver catalyst, to form the homologated carboxylic acid with an additional CH2 group.
This reaction provides a method for the preparative chain elongation of carboxylic acids. Examples discussed include the synthesis of β-amino acids, C.P. molecules, and (R)-(-)-homocitric acid-γ-
This document summarizes Chapter 20 on carboxylic acid derivatives and their reactions. It discusses the nomenclature, structure, reactivity and preparation of acid derivatives including esters, acid chlorides, acid anhydrides, amides, and nitriles. Key reactions covered are nucleophilic acyl substitution reactions, hydrolysis, aminolysis, alcoholysis, and additions to the carbonyl group. Spectroscopic data for analysis of these compounds by IR, 1H NMR, and 13C NMR is also provided.
Catalysis by solid bases [recovered] [autosaved]KANUPRIYASINGH19
This document discusses solid base catalysts as a green approach for chemical synthesis. It describes various types of solid bases including hydrotalcites, zeolites, and amines immobilized on silica. Hydrotalcites have basic sites in the interlayer space and can catalyze aldol condensations and ionone synthesis as a replacement for NaOH. Zeolites with exchanged alkali cations or loaded metal oxides also exhibit basic properties and can catalyze reactions like the Knoevenagel condensation. Immobilizing amines and ammonium groups on silica via grafting produces heterogeneous basic catalysts. Solid bases offer advantages over liquid bases like recyclability, easy separation, and generating less waste
This document provides information about the acetoxylation of olefins, specifically the conversion of ethylene to vinyl acetate. It discusses two processes - a solution-based process and a gas-phase process. The solution-based process uses palladium chloride and copper chloride catalysts in acetic acid. The gas-phase process uses palladium metal catalysts with alkali salts like potassium acetate. Both processes form vinyl acetate as the main product, with acetaldehyde and carbon dioxide as byproducts. The document provides details on the industrial development and operation of these processes, and proposed reaction mechanisms.
This document summarizes a seminar on dissolving metals and Birch reduction presented by Miss. Neha Milind Dhansekhar. The seminar covered: (1) Reduction using metals like Zn, Li, Na, and Mg under neutral and acidic conditions; (2) Birch reduction using Li/Na in liquid ammonia to reduce aromatics and acetylene; and (3) Specific examples of reductions like sodium alcohol reducing ketones to alcohols and Birch reduction reducing aromatic rings.
This document covers topics related to organic chemistry II, including:
- The general formula and nomenclature of carboxylic acids.
- The preparation of acid chlorides from carboxylic acids and their reactivity. Acid chlorides are more reactive than acids due to the chlorine withdrawing electron density.
- Common reactions of acid chlorides including reduction, Friedel-Crafts acylation, and nucleophilic acyl substitution such as hydrolysis, ammonolysis, and alcoholysis.
This document discusses various types of reduction reactions including:
1) Catalytic hydrogenation using metals like Pt, Pd, Ni, Ru, Rh to reduce double and triple bonds.
2) Hydride transfer reactions using sources like LiAlH4, NaBH4 to reduce carbonyl groups, nitro groups, and more.
3) Dissolving metal reductions using reactive metals like Li, Na in ammonia solution (Birch reduction) to reduce aromatics.
4) Specific reducing agents and conditions are described for reducing different functional groups selectively like carbonyls, nitriles, alkynes and more.
This PDF presentation describes briefly my research experiences in synthetic organic. The time period of these research projects range from 1999 to 10/2005. Projects of later positions were also included but not all. Time period, place of work and position were mentioned at the beginning of each project. To noted that all the experimental synthesis, separation/purification, characterization and spectral interpretation were performed independently by me.
This document discusses the multi-step synthesis of benzocaine from p-toluidine. The four steps are: 1) acetylation of p-toluidine to form p-methylacetanilide, 2) oxidation of p-methylacetanilide to form p-acetamidobenzoic acid, 3) hydrolysis of p-acetamidobenzoic acid to form p-aminobenzoic acid (PABA), and 4) Fischer esterification of PABA to form the final product benzocaine. The document analyzes each product using melting point, thin layer chromatography, Fourier transform infrared spectroscopy, and high performance liquid chromatography to monitor the efficiency and progress of the
Complexes of m(ii)sulphates with 4 cyanobenzaldehyde andAlexander Decker
This document describes the synthesis and characterization of ten complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) sulphates with two organic ligands, 4-cynobenzaldehydecyclopropanecarboxylicacidhydrazone (CBHN) and 4-ethylbenzaldehydecyclopropanecarboxylicacidhydrazones (EBHN). The complexes were characterized using techniques such as melting point determination, IR spectroscopy, elemental analysis, conductivity measurements, and electronic spectroscopy. IR data showed that the ligands coordinate to the metal ions through the carbonyl oxygen and azomethine nitrogen. Electronic spectroscopy indicated octahedral geometry for most complexes except for
The document discusses various types of molecular rearrangement reactions. It describes rearrangements that involve the migration of groups between molecules (intermolecular) or within the same molecule (intramolecular). Examples of nucleophilic rearrangements that involve the migration of groups to electron-deficient carbons, nitrogen, or oxygen atoms are provided, including the Pinacole-Pinacolone, Wagner-Meerwein, Benzilic acid, and Schmidt rearrangements. Mechanisms and features of these important rearrangement reactions are also outlined.
The document summarizes the Birch reduction reaction, which involves the reduction of aromatic rings with sodium, potassium, or lithium in liquid ammonia or amines in the presence of alcohol. This adds hydrogen to the 1 and 4 positions of the aromatic ring to form an unconjugated diene. The summary discusses the reaction reagents (alkali metals and alcohol or ammonia solvent), mechanism (electron transfer and proton addition), products (1,4-dihydro derivatives), and applications (synthesis of cyclohexenones, hydrocarbons from naphthalene and anthracene). It also acknowledges the professors who provided guidance on the topic.
IMPORTANT NAMED REACTIONS in Organic synthesis with Introduction, General Mechanism, and their synthetic application covering more than 20 named reactions in it.
The benzoin addition is an addition reaction involving two aldehydes. The reaction generally occurs between aromatic aldehydes or glyoxals. The reaction produces an acyloin. In the classic application benzaldehyde is converted to benzoin
This document summarizes a study that investigated the degradation of halogenated organic compounds (haloorganics) by iron porphyrin complexes as biomimetic models of marine microbial pathways. The study reacted various iodinated substrates with different iron porphyrin complexes and monitored the reactions using UV-Vis spectroscopy and gas chromatography-mass spectrometry. The results showed that the iodo substrates reacted fastest, followed by chloro and bromo substrates. Products identified included methane, ethylene, and the corresponding dehalogenated alkene. Reaction rates correlated with the redox potential of the iron complex, with higher redox potentials corresponding to faster rates. The study provides insights into abiotic marine degradation of haloorgan
Diel's-Alder and Gattermann Koch ReactionsPRUTHVIRAJ K
n organic chemistry, the Diels–Alder reaction is a chemical reaction between a conjugated diene and a substituted alkene, commonly termed the dienophile, to form a substituted cyclohexene derivative. It is the prototypical example of a pericyclic reaction with a concerted mechanism
The Chichibabin reaction is a method for producing 2-aminopyridine derivatives by the reaction of pyridine with sodium amide. It was reported by Aleksei Chichibabin in 1914. The following is the overall form of the general reaction: The direct amination of pyridine with sodium amide takes place in liquid ammonia
This document provides information about carboxylic acids and carboxylic acid derivatives (esters). It discusses the properties, structures, nomenclature, preparation methods, and reactions of carboxylic acids and esters. Key points include:
- Carboxylic acids contain a carboxyl group consisting of a carbonyl and hydroxyl group attached to the same carbon. They have higher boiling points than similar molecules due to hydrogen bonding.
- Esters are carboxylic acid derivatives where the hydroxyl hydrogen is replaced by an alkyl or aryl group. They have pleasant aromas and are slightly soluble in water.
- Carboxylic acids and esters undergo acid-base reactions, esterification,
CBSE Class 12 Chemistry Chapter 10 (Haloalkanes and Haloarenes) | Homi InstituteHomi Institute
Haloalkanes and haloarenes are formed by the replacement of hydrogen atoms in hydrocarbons by halogen atoms. Haloalkanes contain halogen atoms attached to sp3 hybridized carbon atoms of an alkyl group, while haloarenes contain halogen atoms attached to sp2 hybridized carbon atoms of an aryl group. These compounds find wide applications in industry and medicine as solvents, starting materials for synthesis, and components of drugs like chloroquine and halothane. They can be prepared from alcohols, hydrocarbons, and other precursors using various reactions.
The Arndt-Eistert reaction involves the homologation of carboxylic acids through a three step process:
1) Conversion of the acid to the corresponding acid chloride
2) Formation of an α-diazomethyl ketone through reaction with diazomethane
3) Decomposition of the diazoketone, often using a silver catalyst, to form the homologated carboxylic acid with an additional CH2 group.
This reaction provides a method for the preparative chain elongation of carboxylic acids. Examples discussed include the synthesis of β-amino acids, C.P. molecules, and (R)-(-)-homocitric acid-γ-
This document summarizes Chapter 20 on carboxylic acid derivatives and their reactions. It discusses the nomenclature, structure, reactivity and preparation of acid derivatives including esters, acid chlorides, acid anhydrides, amides, and nitriles. Key reactions covered are nucleophilic acyl substitution reactions, hydrolysis, aminolysis, alcoholysis, and additions to the carbonyl group. Spectroscopic data for analysis of these compounds by IR, 1H NMR, and 13C NMR is also provided.
Catalysis by solid bases [recovered] [autosaved]KANUPRIYASINGH19
This document discusses solid base catalysts as a green approach for chemical synthesis. It describes various types of solid bases including hydrotalcites, zeolites, and amines immobilized on silica. Hydrotalcites have basic sites in the interlayer space and can catalyze aldol condensations and ionone synthesis as a replacement for NaOH. Zeolites with exchanged alkali cations or loaded metal oxides also exhibit basic properties and can catalyze reactions like the Knoevenagel condensation. Immobilizing amines and ammonium groups on silica via grafting produces heterogeneous basic catalysts. Solid bases offer advantages over liquid bases like recyclability, easy separation, and generating less waste
This document provides information about the acetoxylation of olefins, specifically the conversion of ethylene to vinyl acetate. It discusses two processes - a solution-based process and a gas-phase process. The solution-based process uses palladium chloride and copper chloride catalysts in acetic acid. The gas-phase process uses palladium metal catalysts with alkali salts like potassium acetate. Both processes form vinyl acetate as the main product, with acetaldehyde and carbon dioxide as byproducts. The document provides details on the industrial development and operation of these processes, and proposed reaction mechanisms.
This document summarizes a seminar on dissolving metals and Birch reduction presented by Miss. Neha Milind Dhansekhar. The seminar covered: (1) Reduction using metals like Zn, Li, Na, and Mg under neutral and acidic conditions; (2) Birch reduction using Li/Na in liquid ammonia to reduce aromatics and acetylene; and (3) Specific examples of reductions like sodium alcohol reducing ketones to alcohols and Birch reduction reducing aromatic rings.
This document covers topics related to organic chemistry II, including:
- The general formula and nomenclature of carboxylic acids.
- The preparation of acid chlorides from carboxylic acids and their reactivity. Acid chlorides are more reactive than acids due to the chlorine withdrawing electron density.
- Common reactions of acid chlorides including reduction, Friedel-Crafts acylation, and nucleophilic acyl substitution such as hydrolysis, ammonolysis, and alcoholysis.
This document discusses various types of reduction reactions including:
1) Catalytic hydrogenation using metals like Pt, Pd, Ni, Ru, Rh to reduce double and triple bonds.
2) Hydride transfer reactions using sources like LiAlH4, NaBH4 to reduce carbonyl groups, nitro groups, and more.
3) Dissolving metal reductions using reactive metals like Li, Na in ammonia solution (Birch reduction) to reduce aromatics.
4) Specific reducing agents and conditions are described for reducing different functional groups selectively like carbonyls, nitriles, alkynes and more.
This PDF presentation describes briefly my research experiences in synthetic organic. The time period of these research projects range from 1999 to 10/2005. Projects of later positions were also included but not all. Time period, place of work and position were mentioned at the beginning of each project. To noted that all the experimental synthesis, separation/purification, characterization and spectral interpretation were performed independently by me.
This document discusses the multi-step synthesis of benzocaine from p-toluidine. The four steps are: 1) acetylation of p-toluidine to form p-methylacetanilide, 2) oxidation of p-methylacetanilide to form p-acetamidobenzoic acid, 3) hydrolysis of p-acetamidobenzoic acid to form p-aminobenzoic acid (PABA), and 4) Fischer esterification of PABA to form the final product benzocaine. The document analyzes each product using melting point, thin layer chromatography, Fourier transform infrared spectroscopy, and high performance liquid chromatography to monitor the efficiency and progress of the
Complexes of m(ii)sulphates with 4 cyanobenzaldehyde andAlexander Decker
This document describes the synthesis and characterization of ten complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) sulphates with two organic ligands, 4-cynobenzaldehydecyclopropanecarboxylicacidhydrazone (CBHN) and 4-ethylbenzaldehydecyclopropanecarboxylicacidhydrazones (EBHN). The complexes were characterized using techniques such as melting point determination, IR spectroscopy, elemental analysis, conductivity measurements, and electronic spectroscopy. IR data showed that the ligands coordinate to the metal ions through the carbonyl oxygen and azomethine nitrogen. Electronic spectroscopy indicated octahedral geometry for most complexes except for
The document discusses various types of molecular rearrangement reactions. It describes rearrangements that involve the migration of groups between molecules (intermolecular) or within the same molecule (intramolecular). Examples of nucleophilic rearrangements that involve the migration of groups to electron-deficient carbons, nitrogen, or oxygen atoms are provided, including the Pinacole-Pinacolone, Wagner-Meerwein, Benzilic acid, and Schmidt rearrangements. Mechanisms and features of these important rearrangement reactions are also outlined.
The document summarizes the Birch reduction reaction, which involves the reduction of aromatic rings with sodium, potassium, or lithium in liquid ammonia or amines in the presence of alcohol. This adds hydrogen to the 1 and 4 positions of the aromatic ring to form an unconjugated diene. The summary discusses the reaction reagents (alkali metals and alcohol or ammonia solvent), mechanism (electron transfer and proton addition), products (1,4-dihydro derivatives), and applications (synthesis of cyclohexenones, hydrocarbons from naphthalene and anthracene). It also acknowledges the professors who provided guidance on the topic.
This document presents a reaction mechanism for the atmospheric photochemical oxidation of benzene initiated by reaction with hydroxyl radicals. It develops an elementary reaction mechanism including 29 reactions and 26 species. Rate constants and thermodynamic parameters are analyzed using quantum Rice-Ramsperger-Kassel theory and group additivity techniques to determine equilibrium concentrations of reaction intermediates and product formation rates under atmospheric conditions. The mechanism accounts for important reaction intermediates like benzene-OH adducts and their reactions leading to ring-opening products such as dicarbonyl compounds.
A micro-review of the Baeyer-Villiger oxidation with recent (2012/2013) references from the literature; last updated on March 1 2013.
The Baeyer-Villiger Oxidation is a popular tool for the synthesis of esters and lactones.
See an animation at: http://www.harinchem.com/named_organic_reactions.html.
Please send feedback or questions through: http://www.harinchem.com/contactpage.aspx
Aldehydes and ketones contain a carbonyl group (>C=O) and can undergo numerous reactions. In aldehydes, the carbonyl is bonded to one alkyl group and one hydrogen. In ketones, it is bonded to two alkyl groups. Common reactions include reduction to alcohols using LiAlH4 or NaBH4, addition of Grignard reagents, and reactions involving the acidic alpha-hydrogens like benzoin condensation, Cannizzaro reaction, and Clemmenson reduction. Other important reactions are the Wittig reaction, Knoevenagel condensation, Wolf-Kishner reduction, and Baeyer-Villiger oxidation.
Dimethyldioxirane mechanism of benzaldehyde oxidationGislaine Marchini
1) Dimethyldioxirane oxidizes benzaldehydes to the corresponding benzoic acids under inert atmosphere. The reaction is relatively insensitive to electronic effects on the benzaldehyde.
2) Under oxygen, benzaldehydes are also oxidized to benzoic acids but some benzoyl formate is also produced via a radical mechanism.
3) The limiting factor in the reaction is the decomposition of dimethyldioxirane to acetol, competing with oxidation of the benzaldehyde.
The document provides information about various organic chemistry reactions including the Baeyer-Villiger oxidation, Shapiro reaction, Suzuki coupling, ozonolysis, and Michael reaction. It discusses the reaction mechanisms, applications in synthesis, and key steps for each reaction. Examples are given of uses in synthesizing natural products and complex molecules.
The document discusses several carbon-carbon bond forming reactions:
1. Aldol condensation allows aldehydes and ketones to undergo self-condensation in the presence of a base to form β-hydroxy carbonyl compounds.
2. The Perkin reaction uses an acid anhydride to form α,β-unsaturated aromatic acids from aromatic aldehydes.
3. The Wittig reaction converts a carbonyl group to an alkene using a phosphonium ylide.
The document discusses various types of molecular rearrangement reactions. It begins by defining rearrangement reactions as those where the atoms or groups in a molecule reshuffle to form a structural isomer of the original substance. Rearrangements are then classified as intermolecular or intramolecular. Several examples of nucleophilic rearrangements are provided, including carbonium ion rearrangements like the pinacol-pinacolone, Wagner-Meerwein, and benzillic acid rearrangements. Nitrogen deficiency rearrangements like the Schmidt, Curtius, Hoffmann, Beckmann, and Lossen rearrangements are also briefly described. The mechanisms and features of several important rearrangements are discussed in more detail.
This document provides a tabular survey and overview of various organocatalysts used in asymmetric organocatalysis reactions, including their reaction scopes and commercial availabilities. It discusses how L-proline and other amino acids like L-phenylalanine are commonly used economical organocatalysts that are readily available. It also outlines how cinchona alkaloids are widely used organocatalysts that are commercially available. In general, the document surveys different organocatalysts and their applications in asymmetric reactions.
Baeyer Villiger Oxidation of Ketones, Cannizzaro Reaction, MPVADITYA ARYA
The document summarizes several organic chemistry reactions:
1) The Baeyer-Villiger oxidation reaction involves the oxidation of ketones with peroxy acids to form esters through a rearrangement reaction.
2) The Cannizzaro reaction involves the base-induced disproportionation of two aldehyde molecules to form a carboxylic acid and primary alcohol.
3) The Meerwein-Ponndorf-Verley (MPV) reduction uses aluminum isopropoxide catalyst in isopropanol to reduce aldehydes and ketones to the corresponding alcohols through a reversible reaction.
A Study of Synthesis and Characterization of Liquid Crystalline Substancesijtsrd
Synthesis of homologous series is achieved and having favourable geometry for the formation of mesophase along with formation of nano sized liquid crystal having good stability with metal free formulation which may be utilized further for the industrial application. The formation of liquid crystal with help of homologous series synthesized and characterization showed it to be metal free liquid crystal made up of oil, surfactant and co surfactant mixture which may open doors of nano gels, gels or microemulsion for liquid crystal. This along with texture study and magnetic study shows that unique properties were characterized and showed that metal free formation of liquid crystals with very less particle size and very good particle stability. M. H. Shah | D. K. Bhoi | M. B. Chauhan | N. B. Patel "A Study of Synthesis and Characterization of Liquid Crystalline Substances" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-6 , October 2022, URL: https://www.ijtsrd.com/papers/ijtsrd51848.pdf Paper URL: https://www.ijtsrd.com/physics/other/51848/a-study-of-synthesis-and-characterization-of-liquid-crystalline-substances/m-h-shah
This document provides an overview of 9 organic reactions: 1) Metal hydride reduction using NaBH4 and LiAlH4, 2) Clemmensen reduction, 3) Birch reduction, 4) Wolff-Kishner reaction, 5) Oppenauer oxidation, 6) Dakin reaction, 7) Beckmann rearrangement, 8) Schmidt rearrangement, and 9) Claisen-Schmidt condensation. For each reaction, it discusses the reaction mechanism, modifications, and applications in organic synthesis and drug development. The document serves as a reference for graduate students and researchers on important carbonyl reactions and their uses in pharmaceutical chemistry.
This document discusses ozone chemistry and the Wittig reaction. It describes the mechanism of ozone addition to double bonds, forming primary and secondary ozonides. The key intermediate in the mechanism is the zwitterion. It also discusses using nucleophilic reduction of secondary ozonides to form carbonyl compounds such as aldehydes and ketones. The Wittig reaction involves using ylides derived from phosphonium salts to displace oxygen from ozonides. This project investigated the cis/trans isomerism and solvent effects of Wittig reactions using three different ylides and solvents in one-flask syntheses of cinnamonitrile, benzylidene succinic anhydride, and methyl cinnamate
Synthesis and identification of nickel (ll) , cobalt (ll) and copper (ll) com...Alexander Decker
1. The document describes the synthesis and characterization of nickel(II), cobalt(II), and copper(II) complexes using sodium-1-amino-9,10-dioxo-4-phenylaminanthracene-2-sulphonate (AB25) as a ligand.
2. The complexes were characterized using techniques like elemental analysis, IR and UV-Vis spectroscopy. Nickel(II) complex was found to be diamagnetic while cobalt(II) and copper(II) complexes were paramagnetic.
3. Based on molar ratio and spectral data, the complexes were determined to have the following formulas: nickel(II) and copper(II) complexes were
Synthesis and identification of nickel (ll) , cobalt (ll) and copper (ll) com...Alexander Decker
1. Nickel(II), cobalt(II), and copper(II) complexes were synthesized using sodium-1-amino-9,10-dioxo-4-phenylamin anthracene-2-sulphonate (acid blue 25) as a ligand.
2. The complexes were characterized using techniques like elemental analysis, IR spectroscopy, and UV-VIS spectroscopy. Their physical properties like electrical conductivity and magnetic properties were also determined.
3. Nickel(II) complex was found to be diamagnetic while cobalt(II) and copper(II) complexes were paramagnetic. Cobalt complex did not conduct electricity while the ligand, nickel(II) complex, and copper(
Muktapishti is a traditional Ayurvedic preparation made from Shoditha Mukta (Purified Pearl), is believed to help regulate thyroid function and reduce symptoms of hyperthyroidism due to its cooling and balancing properties. Clinical evidence on its efficacy remains limited, necessitating further research to validate its therapeutic benefits.
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptxHolistified Wellness
We’re talking about Vedic Meditation, a form of meditation that has been around for at least 5,000 years. Back then, the people who lived in the Indus Valley, now known as India and Pakistan, practised meditation as a fundamental part of daily life. This knowledge that has given us yoga and Ayurveda, was known as Veda, hence the name Vedic. And though there are some written records, the practice has been passed down verbally from generation to generation.
Cell Therapy Expansion and Challenges in Autoimmune DiseaseHealth Advances
There is increasing confidence that cell therapies will soon play a role in the treatment of autoimmune disorders, but the extent of this impact remains to be seen. Early readouts on autologous CAR-Ts in lupus are encouraging, but manufacturing and cost limitations are likely to restrict access to highly refractory patients. Allogeneic CAR-Ts have the potential to broaden access to earlier lines of treatment due to their inherent cost benefits, however they will need to demonstrate comparable or improved efficacy to established modalities.
In addition to infrastructure and capacity constraints, CAR-Ts face a very different risk-benefit dynamic in autoimmune compared to oncology, highlighting the need for tolerable therapies with low adverse event risk. CAR-NK and Treg-based therapies are also being developed in certain autoimmune disorders and may demonstrate favorable safety profiles. Several novel non-cell therapies such as bispecific antibodies, nanobodies, and RNAi drugs, may also offer future alternative competitive solutions with variable value propositions.
Widespread adoption of cell therapies will not only require strong efficacy and safety data, but also adapted pricing and access strategies. At oncology-based price points, CAR-Ts are unlikely to achieve broad market access in autoimmune disorders, with eligible patient populations that are potentially orders of magnitude greater than the number of currently addressable cancer patients. Developers have made strides towards reducing cell therapy COGS while improving manufacturing efficiency, but payors will inevitably restrict access until more sustainable pricing is achieved.
Despite these headwinds, industry leaders and investors remain confident that cell therapies are poised to address significant unmet need in patients suffering from autoimmune disorders. However, the extent of this impact on the treatment landscape remains to be seen, as the industry rapidly approaches an inflection point.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of the physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar lead (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
6. Describe the flow of current around the heart during the cardiac cycle
7. Discuss the placement and polarity of the leads of electrocardiograph
8. Describe the normal electrocardiograms recorded from the limb leads and explain the physiological basis of the different records that are obtained
9. Define mean electrical vector (axis) of the heart and give the normal range
10. Define the mean QRS vector
11. Describe the axes of leads (hexagonal reference system)
12. Comprehend the vectorial analysis of the normal ECG
13. Determine the mean electrical axis of the ventricular QRS and appreciate the mean axis deviation
14. Explain the concepts of current of injury, J point, and their significance
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. Chapter 3, Cardiology Explained, https://www.ncbi.nlm.nih.gov/books/NBK2214/
7. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
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Rasamanikya is a excellent preparation in the field of Rasashastra, it is used in various Kushtha Roga, Shwasa, Vicharchika, Bhagandara, Vatarakta, and Phiranga Roga. In this article Preparation& Comparative analytical profile for both Formulationon i.e Rasamanikya prepared by Kushmanda swarasa & Churnodhaka Shodita Haratala. The study aims to provide insights into the comparative efficacy and analytical aspects of these formulations for enhanced therapeutic outcomes.
1. An Old Dog with New Tricks:
Enjoin Wolff–Kishner Reduction for
Alcohol Deoxygenation and C–C Bond Formations
Presented By:
Stephin Baby
Dept. Of Medicinal Chemistry
MC/2019/21
2. THE PRESENTATION INCLUDES:
Introduction
1
History and
emergence of
Wolff-Kishner
reduction
2 Transitions in
Development3
Evolution and
exploration of
Wolff-Kishner
reduction
4 Conclusion
5 Reference
6
2/21/2020 2
3. INTRODUCTION
The Wolff-Kishner reduction
Nikolai Matveevich Kizhner (1867 – 1935) and Ludwig Wolff (1856 – 1919)
Carbonyl deoxygenation,subsequently developed two unprecedented new types of
chemical transformations:
a) alcohol deoxygenation
b) C–C bond formations
Grignard-type reaction
Conjugate addition
Olefination
Diverse cross-coupling reactions.
2/21/2020
3
4. HISTORY AND EMERGENCE
Kizhner, Professor of Organic Chemistry at the Imperial Tomsk Technological Institute, in
Siberia(1912).Published his report in the Zhurnal Russkogo Fiziko-Khimicheskogo
Obshchestva [Journal of the Russian Physical-Chemical Society]
Wolff, working at the Chemical Institute of Jena University, published a variant of the
same reaction in Justus Liebigs Annalen der Chemie(1912)
The reaction became known as the Wolff reduction until January 10, 1913, when Wolff
acknowledged Kizhner’s priority for the discovery.
In the first disclosure, Kizhner reported the Four deoxygenations.
2/21/2020 4
6. Fig 2: Wolff’s first report of a semicarbazone decomposition
The first reaction reported by Wolff was the conversion of the quinone
monosemicarbazone into the phenol
Ironically, the paper was entitled, “Method for replacing the oxygen atom of ketones and
aldehydes by hydrogen. [First paper.]” No second paper appeared.
Wolff describes that the inspiration for his discovery was an observation by Johannes
Thiele and his student, Willy Barlow.
2/21/2020 6
7. Wolff modified his procedure after obtained sufficient evidence for the involvement of a hydrazone intermediate
Fig 3: Wolff’s decomposition of semicarbazones by base.
Kishners
exploration
Wolff exploration
Camphor(28%) Benzophenone(90%)
Fenchone(28%) Acetophenone(80%)
α-ionone p-Anisaldehyde(66%)
β-ionone Vanillin(67%)
pseudoionone dibenzyl ketone
Furfural(70%) P-aminoacetophenone
carone Micheler’s ketone
Menthone(89%) 2-Hexanone
isothujone
2/21/2020
7
9. Scope and Limitation of the reaction
Scope
The synthesis of the
corticosteroids and sex hormones
Systematic synthesis of
pyrroles(Hans fischer 1929)
Structure elucidations of the
pentacyclic triterpenes(Leopold
Ruzicka 1939)
Wharton reaction
Eschenmoser-Tanabe
fragmentation
C-C bond formations
Grignard-type reactions
Conjugate additions
Transition-metal-catalyzed cross
coupling reactions
Suzuki coupling
Kumada–Corriu coupling
Stille coupling
Hiyama coupling
Negishi coupling
Sonogashira coupling.
2/21/2020 9
10. • Azine formation
• Hydrazone hydrolysis to
alcohols(Eisenlohr and Polenske)
• Required higher temperature for
the reduction proceed to
completion(180 deg.cel)
• Relatively low yields(Fenchone
and camphor)
• Decomposition of the hydrazones
to the alkene
• Time taken for completion of
reaction is more
• Dehalogenation in heterocyclic
compounds
Limitation.
Scope and Limitation of the reaction
2/21/2020 10
12. Mechanistic investigations
THE IONIC MECHANISM
Azo tautomer of the hydrazone
Reacts with hydroxide anion to
give its conjugate base
Loses molecular nitrogen to give the
carbanion
Protonated by the water molecule
Alkane
H. Harry
Szmant(1952)
2/21/2020 12
13. Fig 4: The mechanism and reaction
energy profile for the base-promoted
decomposition of cyclohexanone
hydrazone.
2/21/2020 13
14. Free-radical mechanism
Nitrogen gas & alkane
Azo compound
intermediate
React with a radical to generate
a new carbon radical
Fig 5: A putative free radical mechanism for the Wolff-Kishner reduction2/21/2020 14
15. Which one of the two, predominates???.............
Free radical
Ionic mechanism
Azo tautomer
Free radicals undergo coupling
instead of hydrogen atom
abstraction when the concentration
of hydrazine is low
N-alkylhydrazone as substrate
Hydrogen atom abstraction from
hydrazine when the concentration
of hydrazine is high
2/21/2020 15
16. Modern adaptations of the Wolff-Kishner reduction
Challenge 1
Strongly basic conditions and high
temperatures of the reaction.
Challenge 2
steric hindrance
high concentration of hydrazine
Challenge 3
Hydrolysis by water and subsequent
formation Azo derivatives
Removal of water(distillation) from the reaction
medium and use of anhydrous
01
02
03
Challenges Variation of reaction from primary observation
Relatively unencumbered ketones
2/21/2020 16
17. The Huang-Minlon modification
The first major advance in this reaction was discovered by Professor Huang-
Minlon (or Huang Ming-Long, 1898–1979)
Solvent Base Reaction time
estimated
Ketone to
Hydrazine
ratio
Yield
Soffer and
coworkers(1945)
Diethylene (b.p. 244 °C)
or triethylene
glycol (b.p. 285 °C)
triethanolamine (bp. 335
°C)
Conjugate base of
the solvent as the
base
“
Longer time is
required
“
Usually 1:10
Lower ratio
Good
Poor yield
Whitmore and his
students(1945)
High boiling alcohols
(Acid catalyst)
“ Short time was
required
1:2 Good
2/21/2020 17
18. Fig:6 The first Huang-Minlon modification of the Wolff-Kishner reduction
Outcome
Ease of use and its generally higher yields
2/21/2020 18
19. Bergmann and Orchin(1949)
Bartlett and
Knox(1939)
Sargent(1957)
Gates(1950)Rapoport(1960)
Zhilkibaev(2007)
Determination of the stereochemistry of the
Rauwolfia indole alkaloid, rauwolscine
Pelletier(1954)
3-Ethylacridine has been obtained by reduction of 3-
acetylacridine,reduction of 3-acetyl-9,10 dihydroacridine
thienyl ketones, as well
aldehydes
The reduction of the keto-
lactam to the lactam
Fieser(1948)
Stenhagen(1949)
Non-conjugated unsaturated linear keto-
esters and keto-amides to the straight-chain
carboxylic acid derivatives.
Cason(1949)
G.M. Badger(1948)
Branched-chain ketoacids(β,β-
Dialkyl-γ-ketoesters)
synthesis of the geometric
isomers of hexahydrochrysene
from the diketones
Preparation of the bornane-1-
carboxylic acid by reduction of the
2-bornanone-1-carboxylic acid
Synthesis of cyclobutane
from cyclobutanone
structural and stereochemical studies of the
diterpenes of Agathis australis
Fluorene-1-carboxylic acid from
reduction of the keto-acid
Enzell and Thomas(1965)
Roberts and Sauer(1949) Buu-Ho(1953)
Reduction of the geissoschizine
aldehyde to the methyl compound
His proofs of structure and
stereochemistry(veratrine)
The reduction of 3-aryl-2-azabicyclo[4.4.0]-decan-5-
ones gave good yields of the perhydroisoquinolines
Chatterjee and Prakash(1954)
Long-chain linear keto-acids to
the straight-chain carboxylic acids
2/21/2020 19
20. Nucleophile
used
Solvent Base Yield and Reaction
time
Temperat
ure
Outcome
Moffett and
Hunter
(1951)
anhydrous
hydrazine
Anhydrous
alcohol(methanol)
Anhydrous
alkoxide bases
Na-methoxide
11-ketosteroids-
63-82%
12h
200oC Reduction of
streically hindered
11-ketosteroids
The Barton
modification
(1955)
Anhydrous
hydrazine
Anhydrous
diethylene glycol
Sodium
alkoxide
(conjugate
base)
Hindered
diterpene dione -
69-70%
18-24h
180-
240oC
Reduction of
streically hindered
diterpene dione
The Nagata
modification
(1964)
Hydrazine
dihydrochloride
(Acid catalyzed)
Glycols(Diethylene
glycol or triethylene
glycol)
KOH 3-epi-11-oxo-
ticogenin &
Hindered imines-
90%
200oC Hindered carbonyls
and masked
carbonyl groups,
such as imines
Henbest
modification
(1963)
Hydrazine
semicarbazide
toluene
“
Potassium
tert-butoxide
“
piperidinylpinacolo
ne -83%
4-cholestene –Low
yield
Higher yield
<120oC
“
Lower
temperatures
reductive
elimination of α-
aminoketones
Further modifications………
2/21/2020 20
21. Nucleophile
used
Solvent Base Yield and Reaction
time
Temperat
ure
Outcome
The Cram
modification
(1962)
Hydrazine dimethyl sulfoxide
Potassium
tert-butoxide
Diphenyl ketone-
90%
Cyclohexanone-
80%
RT Reduction at room
temperature
Fig 7:The generation of an alkyldiazene by reduction of a hydrazone carrying a leaving group.
What about not using a base at all ?........
2/21/2020 21
22. Diazene
P-toluenesulfonylhydrazone
• A complex metal hydride(reducing
agent & Base)
• Protic solvents
• NaBH4 or LiAlH4
• Milder Reaction conditions
• Yield is good
• Two steps
• Carried out under conditions of
low pH
• Mixed DMF-sulfolane solvent
• Higher temperatures
• Sodium
cyanoborohydride(Reducing
agent)
• DMF can act as the
deprotonating base
• Higher yields & Single step
Caglioti Modification Hutchins Modification
The Caglioti & Hutchins modification(1964-1967)
2/21/2020 22
23. Synthetic Toolbox
Natural products and & Lead compounds
Desired biological Properties
Largely unexploited
Fossil-based
C feedstocks
‘Un-functionalized’
Selective
Functionalisation
To build up complexity
biomass-based
feedstocks
‘Overfunctionalized’
Selective
Defunctionalisation
by maintaining
complexity
Synthetic Mainstream
2/21/2020 23
25. Unsolved Challenge >>>>
Direct Deoxygentation with High selectivity and efficiency ????.......
One Step Deoxygenation Historical Pathway
I. Benzylic alcohol
II. Allylic alcohol
III. 1,2-dihydroxy compounds
2/21/2020 25
26. One step Methodolgy
Total Synthesis of
Sesquiterpene(Sesquicarene)
Pyridine-SO3 Complex in THF
Sulfate monoester-
intermediate(LiAlH4)0-3oC
C12H12Ti(Benzene titanium)
Deoxygenation and C-C bond
formation
THF is used(quench free
radical)
Allyl alcohol(Trans/cis)
Hydroalumination(Allyl
alcohol&Ethers
LiAlH4 in Zr
compounds(Cp2ZrCl2,ZrCl2)
Also done by Ti compounds
Tungsten Cmplex
Activate C-O bond
WH2Cl2(PMe3)4
Deoxygenate non-
allylic alcohols
Β-cyclodextrin promoted
No cis product
Terminal olefins will be
formed(RT)
E.J Corey(1969)
Henry ledon (1979)
Fumie sato(1980)
Jong-Tae Lee (1990)
Thomas J.crevies(1997)
2/21/2020 26
28. Catalysts used:
Iridium(Ir)
Ruthenium(Ru)
Manganese(Mn)
Substrate scope:
Primary alcohol(Secondary cyclicalcohols >>>>> Steric Hindrance)
Benzylic alcohol>>>ortho-methoxybenzyl alcohol(Low yield)>>>>>Strong
chelation
Allylic alcohol>>> carbon–carbon double bond (C=C) and the hydroxy group
were simultaneously reduced2/21/2020 28
29. A: Initial formation of the active species
B: Alcohol generated complex
C: β-H elimination
D: Regeneration of catalyst
Proposed Mechanism
2/21/2020 29
31. Short Summary
Efficient mainly with benzylic &
allylic alcohol
Harsh conditions
Highly concentrated
solution(10M)>>Scale up
Stoichiometric innocuous
byproducts
Practical reaction
conditions
Synthetically benign
Single step with High
selectivity on 1o alcohols
Great functional group
tolerance
Excellent chemoselectivity
Great regioselectivity
Iridium- and Ruthenium-
catalyzed deoxygenation
methods is that these are
precious metals
Functional-group tolerant
Selective in both primary and
Benzylic alcohol2/21/2020 31
32. C-C Bond Formation
Grignard-Type Reactions
Represented examples for the Ru-catalyzed addition of hydrazone to aldehydes and ketones.
Ru-Catalyzed Addition of Hydrazones with
Aldehydes and Ketone
2/21/2020 32
33. Presynthesize the Hydrazones
Umpolung Carbanion
Metal free surrogates
Good chemoselectivity
Good functional group tolerance
Minor influence of the substituent
Relatively complex substrate
is also tolerated
Characteristics
2/21/2020 33
34. Proposed mechanism for the ruthenium-catalyzed Grignard type addition of umpolung hydrazones
to carbonyls
Proposed mechanism
A: Rapidly metalate
B: Rearrangement
C: Addition product(N2)
2/21/2020 34
N2
35. Classical strategies for amine synthesis
Nucleophilic addition of organometallic reagents
Coupling of carbonyl compounds with imines(Mannich reaction)>>> Enolate chemistry
Unpolung coupling of aldehydes and imines
Pinacol type coupling
Benzoin type coupling
Aldehydes as alkyl carbanion equivalents for Amine synthesis
Ru-Catalyzed Addition of Hydrazone with Imines
Scope of aldehydes for the Ru-catalyzed addition of umpolung hydrazones to imine
2/21/2020 35
36. Characteristics
[Ru(p-cymene)Cl2]2 providing the highest yield>>> The least expensive one
Favored by electron-rich phosphines(1,2-bis(dimethylphosphino)ethane (dmpe) and
tri(tert-butyl)-Phosphine
ligand-to-metal ratio(1:1)
K3PO4(Superior reactivity)
Cesium fluoride(CeF)>>>Additive
Removal of a chloride(Silver triflate)
Scope of Substrates
Aromatic aldehydes showed good reactivity
Halide substituents had a minor influence on the reactivity(Ortho-Least reactive)
Aromatic
Aliphatic
Heterocyclic
2/21/2020 36
37. Ru-Catalyzed Addition of Hydrazone with CO2
CO2 as a carbon feedstock
High abundance
Low cost
Low toxicity
Renewability
Umpolung carboxylation
Operationally simple
protocol
High reactivity
Selectivity under mild
conditions
Good functional group
tolerance
Readily scalable
2/21/2020 37
38. Cross-Coupling Reactions
Ni-Catalyzed Negishi-type Coupling
Efficient construction of C–C bonds
Ni(cod)2/PMe3 system with DBU
Electron-donating PMe3, PPh2Me,Or PPhMe2 were
effective
Chlorobenzene and fluorobenzene did not react
Ar-X Vinyl-X Alkyl-X
X= -Otf,Ots,Oms,Br,I etc…
2/21/2020 38
39. Tunable site selectivity between aryl iodide and tosylate
Broader substrate scope
Greater functional group compatibility
Chemoselectivity
Characteristics
2/21/2020 39
40. Proposed Mechanism
Proposed mechanism for the cross-couplings between aryl electrophiles
2/21/2020 40
Liu, Y. H.; Tang, D. L.; Cao, K. H.; Yu, L.; Han, J.; Xu, Q. J. Catal.2018
41. Pd-Catalyzed Tsuji–Trost Alkylation Reaction
Palladium-catalyzed allylic alkylation
Allylic electrophiles are less reactive
Using the electron-rich NHC ligand (IPr, 1,3-bis(2,6-diisopropylphenyl)
imidazole-2-ylidene)
Characteristics
Good functional group compatibility(ortho,meta,para)
Highly chemo- and regioselective C-alkylated products
High to excellent yields
2/21/2020 41
42. 2/21/2020 42
A tentative mechanism for the palladium-catalyzed allylic alkylation of umpolung carbonyls
43. Conclusion
Exploring synthetic
chemistry inspired
from old classical
reactions
provide a foundation
for the next generation
of chemical syntheses
towards sustainability
Develop fundamental
reaction tools for more
efficient and greener
chemical transformations
Efficient transformation of
natural abundant organic
compounds into chemical
products
44. 2/21/2020 44
Reference
(1) Kishner, N. J. Russ. Phys. Chem. Soc. 1911, 43, 582.
(2) Wolff, L. Justus Liebigs Ann. Chem. 1912, 394, 86.
(3) Li, J. J. Name Reactions, 5th ed; Springer: Switzerland, 2014.
(4) Kuethe, J. T.; Childers, K. G.; Peng, Z.; Journet, M.; Humphrey, G.R.; Vickery, T.; Bachert, D.; Lam, T. T. Org. Process
Res. Dev. 2009,13, 576.
(5) Huang-Minion J. Am. Chem. Soc.1946, 68, 2487
(6) Osdene, T. S.; Timmis, G. M.; Maguire, M. H.; Shaw, G.;Goldwhite, H.; Saunders, B. C.; Clark, E. R.; Epstein, P.
F.;Lamchen, M.; Stephen, A. M.; Tipper, C. F. H.; Eaborn, C.;Mukerjee, S. K.; Seshadri, T. R.; Willenz, J.; Robinson,
R.;Thomas, A. F.; Hickman, J. R.; Kenyon, J.; Crocker, H. P.; Hall, R.H.; Burnell, R. H.; Taylor, W. I.; Watkins, W. M.; Barton,
D. H. R.;Ives, D. A. J.; Thomas, B. R. J. Chem. Soc. 1955, 2038.
(7) Grundon, M. F.; Henbest, H. B.; Scott, M. D. J. Chem. Soc. 1963,1855.
(8) Caglioti, L.; Magi, M. Tetrahedron 1963, 19, 1127.
(9) Cram, D. J.; Sahyun, M. R. V. J. Am. Chem. Soc. 1962, 84, 1734.
(10) Furrow, M. E.; Myers, A. G. J. Am. Chem. Soc. 2004, 126, 5436.
(11) Corey, E. J.; Cheng, X.-M. The Logic of Chemical Synthesis; JohnWiley & Sons: New York, 1989.
(12) Grignard, V. Compt. Rend. 1890, 130, 1322.
(13) Perlmutter, P. Conjugate Addition Reactions in Organic Synthesis;Pergamon Press: New York, 1992.
(14) Miyaura, N.; Yamada, K.; Suzuki, A. Tetrahedron Lett. 1979, 20,3437.
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Hydrazone formed converted cyclohexylhydrazine by Na metal in boiling ethanol ..unexpected product was cyclohexanol
ketone with hydrazine hydrate in ethanol under reflux, and then dried over fused potassium carbonate before further use
exothermic reaction
became self-sustaining, and external heating was no longer required
Wolff deduced that this reaction occurred through an intermediate hydrazone to give the dienone, which then tautomerized to the aromatic product
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