The document outlines various addition reactions to alkenes and alkynes, including addition of HX, H2O, SO4, halogens, and oxidation reactions. It discusses important concepts like Markovnikov's rule, regioselectivity, stereochemistry including anti-Markovnikov additions from hydroboration-oxidation. A variety of methods are covered for converting alkenes and alkynes to alcohols, diols, dihalides, and cleaving carbon-carbon double or triple bonds.
Wagner-Meerwein rearrangements involve the migration of hydrogen or alkyl groups within carbonium ions during rearrangement reactions. Specifically, they refer to [1,2]-rearrangements of hydrogen or alkyl groups between carbon-1 and carbon-2 in carbonium ions that do not contain heteroatoms attached to these carbon centers. An example of a Wagner-Meerwein rearrangement provided is the neopentyl rearrangement, which involves the migration of a methyl group in a carbonium ion.
The Wittig reaction converts aldehydes and ketones to alkenes using phosphorous ylides. A ylide is a molecule with adjacent opposite charges that is prepared from alkyl halides and triphenylphosphene. The ylide attacks the carbonyl carbon of an aldehyde or ketone to form a betaine intermediate. Betaine then eliminates triphenylphosphine oxide to generate the alkene product. For example, acetone reacts with a ylide to form 2-methylpropene.
This document summarizes several organic rearrangement reactions: the Cope rearrangement, Claisen rearrangement, and Curtius rearrangement. The Cope rearrangement involves the [3,3]-sigmatropic rearrangement of 1,5-dienes. The Claisen rearrangement is a carbon-carbon bond forming reaction that rearranges allyl vinyl ethers to γ,δ-unsaturated carbonyls. The Curtius rearrangement converts carboxylic acids to isocyanates through an acid azide intermediate. Mechanisms are provided for each reaction.
The document discusses different types of electrophilic substitution reactions: SE1, SE2, and SEi. SE1 reactions follow first-order kinetics and involve two steps - rate-determining ionization and fast combination. SE2 reactions also follow first-order kinetics, but occur in a single step through a transition state. SE2 reactions can result in retention or inversion of configuration. SEi reactions are concerted mechanisms where the electrophile assists in removing the leaving group, leading to retention of configuration.
The document discusses different types of substitution reactions including nucleophilic substitution, electrophilic substitution, and free radical substitution. It provides details on the mechanisms, kinetics, stereochemistry and factors affecting the rate of nucleophilic substitution reactions SN1 and SN2. SN1 follows a unimolecular mechanism involving a carbocation intermediate while SN2 follows a bimolecular mechanism with a single concerted transition state. The document also discusses electrophilic aromatic substitution reactions and addition and elimination reactions of alkenes and alkynes.
The document discusses various types of aliphatic nucleophilic substitution reactions and their mechanisms. It covers SN2 and SN1 mechanisms in detail, providing evidence that supports each. It also discusses borderline cases where reactions have characteristics of both SN1 and SN2, and other mechanisms like SN1', SNi, SET, and addition-elimination that may occur under different conditions. Specific examples of nucleophilic substitution are discussed at allylic, trigonal, and vinylic carbons that may proceed by different pathways than typical SN1 or SN2 reactions.
Addition reactions occur when two reactants combine to form a new product with no leftover atoms. In an addition reaction, new groups are added to the starting material, breaking a pi bond and forming two sigma bonds. Addition reactions involve the addition of electrophiles, radicals, or nucleophiles across multiple bonds such as carbon-carbon double or triple bonds.
1. The document outlines different elimination reaction mechanisms including E2, E1, and E1cb.
2. It discusses the regiochemistry and stereochemistry of elimination reactions and how Zaytzeff's rule and Hofmann's rule apply.
3. The key differences between the E2, E1, and E1cb mechanisms are described along with factors that determine whether substitution or elimination will occur for a given reaction.
Wagner-Meerwein rearrangements involve the migration of hydrogen or alkyl groups within carbonium ions during rearrangement reactions. Specifically, they refer to [1,2]-rearrangements of hydrogen or alkyl groups between carbon-1 and carbon-2 in carbonium ions that do not contain heteroatoms attached to these carbon centers. An example of a Wagner-Meerwein rearrangement provided is the neopentyl rearrangement, which involves the migration of a methyl group in a carbonium ion.
The Wittig reaction converts aldehydes and ketones to alkenes using phosphorous ylides. A ylide is a molecule with adjacent opposite charges that is prepared from alkyl halides and triphenylphosphene. The ylide attacks the carbonyl carbon of an aldehyde or ketone to form a betaine intermediate. Betaine then eliminates triphenylphosphine oxide to generate the alkene product. For example, acetone reacts with a ylide to form 2-methylpropene.
This document summarizes several organic rearrangement reactions: the Cope rearrangement, Claisen rearrangement, and Curtius rearrangement. The Cope rearrangement involves the [3,3]-sigmatropic rearrangement of 1,5-dienes. The Claisen rearrangement is a carbon-carbon bond forming reaction that rearranges allyl vinyl ethers to γ,δ-unsaturated carbonyls. The Curtius rearrangement converts carboxylic acids to isocyanates through an acid azide intermediate. Mechanisms are provided for each reaction.
The document discusses different types of electrophilic substitution reactions: SE1, SE2, and SEi. SE1 reactions follow first-order kinetics and involve two steps - rate-determining ionization and fast combination. SE2 reactions also follow first-order kinetics, but occur in a single step through a transition state. SE2 reactions can result in retention or inversion of configuration. SEi reactions are concerted mechanisms where the electrophile assists in removing the leaving group, leading to retention of configuration.
The document discusses different types of substitution reactions including nucleophilic substitution, electrophilic substitution, and free radical substitution. It provides details on the mechanisms, kinetics, stereochemistry and factors affecting the rate of nucleophilic substitution reactions SN1 and SN2. SN1 follows a unimolecular mechanism involving a carbocation intermediate while SN2 follows a bimolecular mechanism with a single concerted transition state. The document also discusses electrophilic aromatic substitution reactions and addition and elimination reactions of alkenes and alkynes.
The document discusses various types of aliphatic nucleophilic substitution reactions and their mechanisms. It covers SN2 and SN1 mechanisms in detail, providing evidence that supports each. It also discusses borderline cases where reactions have characteristics of both SN1 and SN2, and other mechanisms like SN1', SNi, SET, and addition-elimination that may occur under different conditions. Specific examples of nucleophilic substitution are discussed at allylic, trigonal, and vinylic carbons that may proceed by different pathways than typical SN1 or SN2 reactions.
Addition reactions occur when two reactants combine to form a new product with no leftover atoms. In an addition reaction, new groups are added to the starting material, breaking a pi bond and forming two sigma bonds. Addition reactions involve the addition of electrophiles, radicals, or nucleophiles across multiple bonds such as carbon-carbon double or triple bonds.
1. The document outlines different elimination reaction mechanisms including E2, E1, and E1cb.
2. It discusses the regiochemistry and stereochemistry of elimination reactions and how Zaytzeff's rule and Hofmann's rule apply.
3. The key differences between the E2, E1, and E1cb mechanisms are described along with factors that determine whether substitution or elimination will occur for a given reaction.
This document discusses nucleophilic substitution reactions. It begins by defining nucleophiles as negatively charged ions or neutral molecules with a lone pair of electrons. It then explains the mechanisms of the SN2 and SN1 reactions. The SN2 is a concerted bimolecular reaction where the nucleophile attacks from the backside of the substrate, inverting the configuration. The SN1 is a unimolecular reaction that proceeds through a carbocation intermediate, allowing for retention or inversion of configuration. Finally, it discusses factors like temperature, nucleophile strength, and substrate structure that determine whether a reaction will proceed by SN1 or SN2.
The document discusses carbenes, which are molecules containing a neutral carbon atom with two unshared valence electrons. Carbenes can be classified as singlets or triplets based on their electronic structure. The document also describes the Wolff rearrangement, where α-diazoketones lose nitrogen to form reactive ketenes. Some applications of the Wolff rearrangement include the synthesis of carboxylic acid analogues, acid amides from carboxylic acids, and esters from carboxylic acids.
The presentation discusses rearrangement reactions, which involve the migration of an atom or group within a molecule to form a structural isomer. It defines rearrangement and provides examples of types including those to electron deficient carbons, nitrogens, and oxygens, as well as electron-rich carbons and aromatic systems. Mechanisms are presented for rearrangements involving migration to various electron-withdrawing or -releasing centers.
The Hofmann rearrangement involves the reaction of an amide with bromine in a basic solution, resulting in the conversion of the amide to an amine with one fewer carbon atoms. Specifically, the alkyl group migrates from the amide's carbonyl carbon to its nitrogen, forming an isocyanate intermediate. Hydrolysis and decarboxylation of the isocyanate then produces the final amine product along with carbon dioxide. Examples provided show this rearrangement converting an amide to a structurally similar amine. The Curtius reaction, Lossen reaction, and decomposition of acyl azides can also involve Hofmann-type rearrangements.
1. Carbenes are neutral molecules containing a divalent carbon atom with two unshared valence electrons. They exist in both singlet and triplet states depending on the electronic spin.
2. Carbenes undergo insertion reactions into X-H and C-C bonds. They also add across double bonds, with singlet carbenes preserving alkene stereochemistry and triplet carbenes losing it.
3. Carbenes are generated by reactions such as α-elimination of halogenated compounds with base or decomposition of diazo compounds. They can rearrange through migrations such as the Wolff or Arndt-Eistert reactions.
The document discusses several rearrangement reactions including the pinacol rearrangement, Beckmann rearrangement, Heck reaction, ozonolysis, and Grignard reaction. The pinacol rearrangement involves the acid-catalyzed rearrangement of vicinal diols to ketones or aldehydes. The Beckmann rearrangement converts ketoximes to N-substituted amides. The Heck reaction is a palladium-catalyzed coupling of aryl or alkenyl halides with alkenes. Ozonolysis uses ozone to cleave alkenes and alkynes, replacing the multiple bond with a carbonyl. Grignard reagents are important in organic synthesis.
Metal-carbene complexes contain transition metals bonded to carbene ligands. There are two main types: Shrock and Fischer carbene complexes. Shrock carbenes use early transition metals and form via α-elimination, with the carbene carbon being nucleophilic. Fischer carbenes use late transition metals and form by nucleophilic attack, with the carbene carbon being electrophilic. Applications include alkene metathesis catalysis and the Fischer-Tropsch process for hydrocarbon synthesis.
The document discusses elimination reactions, specifically E1 and β-elimination reactions. It explains that E1 reactions proceed through a two-step unimolecular mechanism, with the first step being rate-determining. Factors that affect E1 reactions include the stability of the carbocation intermediate, steric effects, and the ability of the base to stabilize the carbocation. Rearrangements can also occur through carbocation migration to form more stable products.
This document discusses organic reaction intermediates, specifically carbocations and carbanions. It defines them as positively or negatively charged carbon-containing ions that are formed during chemical reactions and then react further to form final products. The key features, methods of formation, factors affecting stability, and synthetic applications of carbocations and carbanions are described. Inductive effects, resonance effects, and hyperconjugation influence the stability of these intermediates. Carbocations and carbanions are involved in many common organic reaction types such as eliminations, substitutions, additions, and rearrangements.
Electrophilic additions involve reactions of alkenes where the pi electrons in the double bond attack an electrophile. There are several types of additions including addition of HX, halogens, water, alcohols, and hydroboration. The mechanism typically involves formation of a carbocation intermediate that is then attacked by the nucleophile. Addition occurs regioselectively according to Markovnikov's rule, favoring the most stable carbocation. Exceptions include free radical additions, which give the anti-Markovnikov product. Oxymercuration-demercuration and hydroboration allow for Markovnikov addition without rearrangements.
Carbanions are carbon atoms with a negative charge that are formed through various mechanisms. They can be classified based on their formation method such as through heterocyclic cleavage, proton abstraction using a base, decarboxylation, addition of a nucleophile to an alkene, or formation of an organometallic compound. Carbanion stability depends on factors like the electronegativity of the carbon, inductive effects, resonance effects, and attachment to sulfur or phosphorus. Aromatic carbanions and those with electron-withdrawing groups are particularly stable due to resonance delocalization. Carbanions have applications in reactions like the Perkin reaction, Claisen condensation, benzoin condensation,
The McMurry coupling reaction is used to join two aryl groups through an ethylene bridge, producing a mixture of (E)- and (Z)-isomers with the (E)-isomer predominating. It involves the coordination of the aryl groups to a titanium center in its mechanism. The reaction has applications in organic synthesis and is commonly used to form C-C bonds between two aryl substituents.
This document provides a summary of nucleophilic substitution reactions. It discusses the mechanisms of SN1 and SN2 reactions. SN1 is a two-step, unimolecular reaction that proceeds through a carbocation intermediate. It favors tertiary halogenoalkanes due to stability of the carbocation. SN2 is a one-step, bimolecular reaction where bond breaking and formation occur simultaneously. It favors primary halogenoalkanes due to less steric hindrance allowing frontside attack. Factors like the nature of the halogen, halogenoalkane, and nucleophile affect the rate of these substitution reactions.
The document discusses various aromatic electrophilic substitution reactions including Vilsmeier-Haack formylation, Reimer-Tiemann reaction, Gattermann-Koch formylation, and Kolbe-Schmitt reaction. It provides details on the reaction conditions, mechanisms, substrates used, and products formed for each reaction. It also discusses some exceptions and problems related to these reactions.
The document discusses migratory aptitude in rearrangement reactions. It defines migratory aptitude as the relative ability of a migrating group to migrate in a rearrangement reaction. Factors that affect migratory aptitude include the stability of the carbocation formed and the electron density of the migrating group. Aryl groups generally have higher migratory aptitude than alkyl groups. The document also describes different types of rearrangement reactions and the mechanisms of nucleophilic rearrangements.
IMPORTANT NAMED REACTIONS in Organic synthesis with Introduction, General Mechanism, and their synthetic application covering more than 20 named reactions in it.
An organic species which has a carbon atom bearing only six electrons in its outermost shell and has a positive charge is called carbocation.
The positively charged carbon of carbocation is sp2 hybridized.
The unhybridized p-orbital remains vacant.
They are highly reactive and act as reaction intermediate.
They are also called carbonium ion.
The document discusses the Von Richter rearrangement and Smiles rearrangement.
The Von Richter rearrangement involves the displacement of a nitro group by cyanide ion on an aromatic compound, with the carboxyl group entering ortho to the displaced nitro group. Evidence supports a mechanism where one oxygen of the carboxyl group comes from the nitro group and one from solvent.
The Smiles rearrangement involves an intramolecular nucleophilic substitution where a leaving group is displaced by a nucleophile activated by an ortho nitro group. Examples are given of substrates that undergo Smiles rearrangement where the linking chain can be aromatic or aliphatic. Electron withdrawing groups para to the nucleophile retard the
A carbene is any neutral carbon species which contains a non-bonding valance pair of electrons.
Contributed by Alison Brown & Nathan Buehler, Undergraduates, University of Utah
The Diels-Alder reaction is a [4+2] cycloaddition between a conjugated diene and a substituted alkene (dienophile) to form a cyclohexene ring. It was discovered in 1928 by Otto Diels and Kurt Alder. The reaction proceeds in a single, concerted step through a transition state and can be accelerated by heating or using catalysts. It is useful for synthesizing 6-membered rings in a stereoselective and stereospecific manner. Lewis acids are commonly used to catalyze the reaction by activating the dienophile. Chiral dienes and dienophiles, as well as chiral Lewis acids, allow for asymmetric Diels-A
1. Addition reactions of alkenes include halogenation, halohydrin formation, hydrogenation, hydration, and hydroboration-oxidation.
2. Halogenation involves the addition of halogens such as bromine or chlorine to the double bond following a free radical mechanism.
3. Hydration can occur through acid-catalyzed addition of water, oxymercuration-demercuration which proceeds through a mercurinium ion, or hydroboration-oxidation which gives the opposite regioselectivity of hydration compared to other methods.
This document discusses nucleophilic substitution reactions. It begins by defining nucleophiles as negatively charged ions or neutral molecules with a lone pair of electrons. It then explains the mechanisms of the SN2 and SN1 reactions. The SN2 is a concerted bimolecular reaction where the nucleophile attacks from the backside of the substrate, inverting the configuration. The SN1 is a unimolecular reaction that proceeds through a carbocation intermediate, allowing for retention or inversion of configuration. Finally, it discusses factors like temperature, nucleophile strength, and substrate structure that determine whether a reaction will proceed by SN1 or SN2.
The document discusses carbenes, which are molecules containing a neutral carbon atom with two unshared valence electrons. Carbenes can be classified as singlets or triplets based on their electronic structure. The document also describes the Wolff rearrangement, where α-diazoketones lose nitrogen to form reactive ketenes. Some applications of the Wolff rearrangement include the synthesis of carboxylic acid analogues, acid amides from carboxylic acids, and esters from carboxylic acids.
The presentation discusses rearrangement reactions, which involve the migration of an atom or group within a molecule to form a structural isomer. It defines rearrangement and provides examples of types including those to electron deficient carbons, nitrogens, and oxygens, as well as electron-rich carbons and aromatic systems. Mechanisms are presented for rearrangements involving migration to various electron-withdrawing or -releasing centers.
The Hofmann rearrangement involves the reaction of an amide with bromine in a basic solution, resulting in the conversion of the amide to an amine with one fewer carbon atoms. Specifically, the alkyl group migrates from the amide's carbonyl carbon to its nitrogen, forming an isocyanate intermediate. Hydrolysis and decarboxylation of the isocyanate then produces the final amine product along with carbon dioxide. Examples provided show this rearrangement converting an amide to a structurally similar amine. The Curtius reaction, Lossen reaction, and decomposition of acyl azides can also involve Hofmann-type rearrangements.
1. Carbenes are neutral molecules containing a divalent carbon atom with two unshared valence electrons. They exist in both singlet and triplet states depending on the electronic spin.
2. Carbenes undergo insertion reactions into X-H and C-C bonds. They also add across double bonds, with singlet carbenes preserving alkene stereochemistry and triplet carbenes losing it.
3. Carbenes are generated by reactions such as α-elimination of halogenated compounds with base or decomposition of diazo compounds. They can rearrange through migrations such as the Wolff or Arndt-Eistert reactions.
The document discusses several rearrangement reactions including the pinacol rearrangement, Beckmann rearrangement, Heck reaction, ozonolysis, and Grignard reaction. The pinacol rearrangement involves the acid-catalyzed rearrangement of vicinal diols to ketones or aldehydes. The Beckmann rearrangement converts ketoximes to N-substituted amides. The Heck reaction is a palladium-catalyzed coupling of aryl or alkenyl halides with alkenes. Ozonolysis uses ozone to cleave alkenes and alkynes, replacing the multiple bond with a carbonyl. Grignard reagents are important in organic synthesis.
Metal-carbene complexes contain transition metals bonded to carbene ligands. There are two main types: Shrock and Fischer carbene complexes. Shrock carbenes use early transition metals and form via α-elimination, with the carbene carbon being nucleophilic. Fischer carbenes use late transition metals and form by nucleophilic attack, with the carbene carbon being electrophilic. Applications include alkene metathesis catalysis and the Fischer-Tropsch process for hydrocarbon synthesis.
The document discusses elimination reactions, specifically E1 and β-elimination reactions. It explains that E1 reactions proceed through a two-step unimolecular mechanism, with the first step being rate-determining. Factors that affect E1 reactions include the stability of the carbocation intermediate, steric effects, and the ability of the base to stabilize the carbocation. Rearrangements can also occur through carbocation migration to form more stable products.
This document discusses organic reaction intermediates, specifically carbocations and carbanions. It defines them as positively or negatively charged carbon-containing ions that are formed during chemical reactions and then react further to form final products. The key features, methods of formation, factors affecting stability, and synthetic applications of carbocations and carbanions are described. Inductive effects, resonance effects, and hyperconjugation influence the stability of these intermediates. Carbocations and carbanions are involved in many common organic reaction types such as eliminations, substitutions, additions, and rearrangements.
Electrophilic additions involve reactions of alkenes where the pi electrons in the double bond attack an electrophile. There are several types of additions including addition of HX, halogens, water, alcohols, and hydroboration. The mechanism typically involves formation of a carbocation intermediate that is then attacked by the nucleophile. Addition occurs regioselectively according to Markovnikov's rule, favoring the most stable carbocation. Exceptions include free radical additions, which give the anti-Markovnikov product. Oxymercuration-demercuration and hydroboration allow for Markovnikov addition without rearrangements.
Carbanions are carbon atoms with a negative charge that are formed through various mechanisms. They can be classified based on their formation method such as through heterocyclic cleavage, proton abstraction using a base, decarboxylation, addition of a nucleophile to an alkene, or formation of an organometallic compound. Carbanion stability depends on factors like the electronegativity of the carbon, inductive effects, resonance effects, and attachment to sulfur or phosphorus. Aromatic carbanions and those with electron-withdrawing groups are particularly stable due to resonance delocalization. Carbanions have applications in reactions like the Perkin reaction, Claisen condensation, benzoin condensation,
The McMurry coupling reaction is used to join two aryl groups through an ethylene bridge, producing a mixture of (E)- and (Z)-isomers with the (E)-isomer predominating. It involves the coordination of the aryl groups to a titanium center in its mechanism. The reaction has applications in organic synthesis and is commonly used to form C-C bonds between two aryl substituents.
This document provides a summary of nucleophilic substitution reactions. It discusses the mechanisms of SN1 and SN2 reactions. SN1 is a two-step, unimolecular reaction that proceeds through a carbocation intermediate. It favors tertiary halogenoalkanes due to stability of the carbocation. SN2 is a one-step, bimolecular reaction where bond breaking and formation occur simultaneously. It favors primary halogenoalkanes due to less steric hindrance allowing frontside attack. Factors like the nature of the halogen, halogenoalkane, and nucleophile affect the rate of these substitution reactions.
The document discusses various aromatic electrophilic substitution reactions including Vilsmeier-Haack formylation, Reimer-Tiemann reaction, Gattermann-Koch formylation, and Kolbe-Schmitt reaction. It provides details on the reaction conditions, mechanisms, substrates used, and products formed for each reaction. It also discusses some exceptions and problems related to these reactions.
The document discusses migratory aptitude in rearrangement reactions. It defines migratory aptitude as the relative ability of a migrating group to migrate in a rearrangement reaction. Factors that affect migratory aptitude include the stability of the carbocation formed and the electron density of the migrating group. Aryl groups generally have higher migratory aptitude than alkyl groups. The document also describes different types of rearrangement reactions and the mechanisms of nucleophilic rearrangements.
IMPORTANT NAMED REACTIONS in Organic synthesis with Introduction, General Mechanism, and their synthetic application covering more than 20 named reactions in it.
An organic species which has a carbon atom bearing only six electrons in its outermost shell and has a positive charge is called carbocation.
The positively charged carbon of carbocation is sp2 hybridized.
The unhybridized p-orbital remains vacant.
They are highly reactive and act as reaction intermediate.
They are also called carbonium ion.
The document discusses the Von Richter rearrangement and Smiles rearrangement.
The Von Richter rearrangement involves the displacement of a nitro group by cyanide ion on an aromatic compound, with the carboxyl group entering ortho to the displaced nitro group. Evidence supports a mechanism where one oxygen of the carboxyl group comes from the nitro group and one from solvent.
The Smiles rearrangement involves an intramolecular nucleophilic substitution where a leaving group is displaced by a nucleophile activated by an ortho nitro group. Examples are given of substrates that undergo Smiles rearrangement where the linking chain can be aromatic or aliphatic. Electron withdrawing groups para to the nucleophile retard the
A carbene is any neutral carbon species which contains a non-bonding valance pair of electrons.
Contributed by Alison Brown & Nathan Buehler, Undergraduates, University of Utah
The Diels-Alder reaction is a [4+2] cycloaddition between a conjugated diene and a substituted alkene (dienophile) to form a cyclohexene ring. It was discovered in 1928 by Otto Diels and Kurt Alder. The reaction proceeds in a single, concerted step through a transition state and can be accelerated by heating or using catalysts. It is useful for synthesizing 6-membered rings in a stereoselective and stereospecific manner. Lewis acids are commonly used to catalyze the reaction by activating the dienophile. Chiral dienes and dienophiles, as well as chiral Lewis acids, allow for asymmetric Diels-A
1. Addition reactions of alkenes include halogenation, halohydrin formation, hydrogenation, hydration, and hydroboration-oxidation.
2. Halogenation involves the addition of halogens such as bromine or chlorine to the double bond following a free radical mechanism.
3. Hydration can occur through acid-catalyzed addition of water, oxymercuration-demercuration which proceeds through a mercurinium ion, or hydroboration-oxidation which gives the opposite regioselectivity of hydration compared to other methods.
The document discusses various pericyclic reactions including cycloaddition reactions. It describes the Alder ene reaction, Diels-Alder reaction, and 1,3-dipolar cycloaddition reactions. These reactions involve the concerted formation of new sigma bonds from pi bonds in a single step without intermediates. The document also discusses factors that influence the regioselectivity and stereoselectivity of these reactions such as orbital interactions and substituents.
The document summarizes key concepts about alkene reactions:
1) Markovnikov addition results in the addition occurring on the carbon with the most hydrogen substituents, giving the more substituted primary carbocation which is most stable.
2) Hydroboration follows anti-Markovnikov addition, with the BH3 group adding to the less substituted carbon. Oxidation then occurs with H2O2/NaOH through a 1,2-shift to give anti-Markovnikov addition.
3) Organoboranes are unstable and hydroboration involves coordination of BH3 to the alkene, allowing for stereospecific anti-Markovnikov addition
I hope You all like it. I hope It is very beneficial for you all. I really thought that you all get enough knowledge from this presentation. This presentation is about materials and their classifications. After you read this presentation you knowledge is not as before.
The lecture discusses the mechanisms of ozonolysis and radical addition reactions to alkenes. Ozonolysis involves a three step mechanism where ozone cleaves the alkene to form an ozonide intermediate which then decomposes to a carbonyl compound. Radical addition reactions involve a three step chain reaction mechanism of initiation, propagation, and termination. The stability of radical intermediates is influenced by resonance stabilization, which explains why styrene reacts with HBr to give a single, benzylic bromide product.
Alkenes and alkynes can be synthesized through elimination and dehydration reactions. E2 eliminations proceed through a coplanar transition state to form the most substituted alkene based on Zaitsev's rule. Alkynes are formed by dehydrohalogenation or alkylation of terminal alkynes. Hydrogenation converts unsaturated hydrocarbons to alkanes or allows control of alkene stereochemistry. Unsaturation numbers index the degree of unsaturation in organic structures.
Halogenoalkanes, also known as alkyl halides, contain carbon-halogen bonds. They can be synthesized through free radical substitution or electrophilic addition reactions. Nucleophilic substitution reactions of halogenoalkanes produce alcohols or other products depending on the solvent. In aqueous solutions, hydroxide acts as a nucleophile to form alcohols via SN1 or SN2 mechanisms. In alcoholic solutions, hydroxide acts as a base to eliminate halogens and form alkenes. Both substitution and elimination reactions occur simultaneously but the solvent influences which pathway dominates.
This document summarizes hydrogenation reactions using both heterogeneous and homogeneous catalysts. It discusses the mechanisms and selectivity of hydrogenation of alkenes, carbonyls, nitriles, nitro groups and azides using catalysts like platinum, palladium and rhodium. It also covers directed hydrogenation, asymmetric hydrogenation and transfer hydrogenation reactions. The order of reactivity for reducing different functional groups is provided.
The document contains information about 5 students' matric numbers and a passage discussing alkyl halides. It defines alkyl halides and describes their classification, nomenclature, physical properties, synthesis from alcohols and alkenes, and reactions including nucleophilic substitution and elimination. Examples are provided to illustrate key concepts and reaction mechanisms.
The document describes alkyl halides (haloalkanes). It discusses their classification based on the number of halogen atoms present, as well as based on the class of carbon. It provides examples of monohaloalkanes, dihaloalkanes and trihaloalkanes. The document also discusses common and IUPAC nomenclature of haloalkanes, isomerism, general methods of preparation from alkanes, alkenes and alcohols. It describes the physical and chemical properties of haloalkanes including their reactivity towards nucleophilic substitution reactions.
Thiols and sulfides are sulfur analogs of alcohols and ethers, respectively. Thiols (RSH) contain a mercapto (-SH) group and are analogous to alcohols. Sulfides (RSR') are analogous to ethers. Thiols and sulfides are named similarly to their oxygen counterparts, but with "-thiol" or "sulfide" replacing the alcohol or ether suffix. Sulfur replaces the oxygen in the functional group.
The document discusses SN1 and SN2 reaction mechanisms of alcohols. Tertiary alcohols undergo SN1 reactions with hydrogen halides faster than secondary or primary alcohols due to their ability to form stable carbocation intermediates. Primary alcohols favor SN2 reactions. Polar solvents can stabilize carbocations and favor the SN1 pathway. Common reagents used to convert alcohols to alkyl halides include thionyl chloride, phosphorus halides, and halogenation using sodium halides.
Thiols and sulfides are sulfur analogs of alcohols and ethers, respectively. Thiols contain an R-S-H functional group and are named with the suffix -thiol. Sulfides contain an R-S-R' group and are named similarly to ethers with sulfide replacing ether. Practice problems involve naming thiols and sulfides. Halogenation of alkanes involves radical initiation by heat or light followed by radical propagation and termination reactions. The reactivity depends on the halogen used as well as the stability of the radical intermediates formed.
Chemical reactions involve the rearrangement of atoms when substances undergo chemical changes. There are several signs that indicate a chemical reaction has occurred, such as a change in color, gas evolution, temperature change, state change, or precipitate formation. Chemical reactions can be described by word equations or chemical equations, with the latter providing a more concise representation where the reactants are on the left and products on the right, separated by an arrow. Chemical equations must satisfy the law of conservation of mass and show correct formulas and phases for substances. Balanced chemical equations ensure equal numbers of each type of atom are present on both sides. Common types of chemical reactions include combination, decomposition, displacement, and redox reactions.
This document discusses properties of aqueous solutions and acid-base reactions. It describes how ionic compounds and electrolytes dissolve in water, forming ions that are solvated. Precipitation reactions that form insoluble products are explained. Strong and weak acids and bases are defined, and neutralization reactions that produce salts and water are covered. Some acid-base reactions evolve gas as one of the products.
Chemical reactions involve the rearrangement of atoms and the formation of new substances. There are several types of chemical reactions including combination, decomposition, single displacement, double displacement, and redox reactions. Balanced chemical equations are used to represent these reactions and must satisfy the law of conservation of mass.
The document summarizes the dehydration of 2-methylcyclohexanol to produce alkene products via an acid-catalyzed E1 elimination reaction using phosphoric acid. Key steps include protonation of the alcohol by phosphoric acid, removal of water to form a carbocation, rearrangement of the carbocation, and elimination of a proton by phosphoric acid to form the alkene product and regenerate the acid catalyst. Experimental procedures are outlined for performing the reaction with phosphoric acid instead of sulfuric acid and for collecting and analyzing the product mixture using distillation, bromine and GC testing. Safety cautions are noted for the corrosive and flammable/toxic reagents used.
1. Quaternary alkylammonium hydroxide undergoes elimination on heating to give the corresponding alkene through an E2 reaction.
2. Elimination reactions can occur through either an E1 or E2 mechanism. E2 reactions are favored with strong bases and hindered substrates, occurring through a concerted mechanism without a carbocation intermediate. E1 reactions involve the formation of a carbocation intermediate and are favored with weaker bases and good leaving groups.
3. Both substitution and elimination reactions are possible depending on factors like the nucleophilicity of the reagent, the stability of any carbocation intermediate, and the ability of the substrate to undergo the concerted E2 mechanism. Strong nucle
Review on Organic Chemical Reactions (1).pptAliceCRivera
I apologize, upon further review I do not have enough information to determine the products of the reaction you asked about. The document provided describes various types of organic chemical reactions but does not include any specific reactions to analyze.
Crystalline solids can be classified into four main categories based on the type of intermolecular forces present: molecular solids, ionic solids, metallic solids, and covalent solids. Molecular solids are further divided into nonpolar, polar, and hydrogen-bonded types. Ionic solids are formed from electrostatic attractions between cations and anions. Metallic solids contain a sea of free electrons that allow for high conductivity. Covalent solids form giant molecular structures with strong directional bonds, making them very hard and brittle.
Crystalline solids can be classified into four main categories based on the type of intermolecular forces present: molecular solids, ionic solids, metallic solids, and covalent solids. Molecular solids are further divided into nonpolar, polar, and hydrogen-bonded types. Ionic solids are formed from electrostatic attractions between cations and anions. Metallic solids contain a sea of free electrons that allow for high conductivity. Covalent solids form giant covalent structures with strong directional bonds, making them very hard and with high melting points.
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This document appears to be about a sample presentation. While no other details are provided in the document itself, it seems to be providing an example of what a presentation might look like or include. The brevity of the document suggests it is meant to serve as a placeholder or template for an actual presentation rather than containing substantive presentation content on its own.
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𝐃𝐢𝐬𝐜𝐮𝐬𝐬 𝐭𝐡𝐞 𝐄𝐏𝐏 𝐂𝐮𝐫𝐫𝐢𝐜𝐮𝐥𝐮𝐦 𝐢𝐧 𝐭𝐡𝐞 𝐏𝐡𝐢𝐥𝐢𝐩𝐩𝐢𝐧𝐞𝐬:
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Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
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Andreas Schleicher presents PISA 2022 Volume III - Creative Thinking - 18 Jun...EduSkills OECD
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The History of NZ 1870-1900.
Making of a Nation.
From the NZ Wars to Liberals,
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Chemistry 343 chapter_8
1. Addition Reactions
• Addition Reactions to Alkenes (Section 8.1)
• Markovnikov’s Rule (Section 8.2)
• Stereochemistry of Ionic Addition to Alkenes (Section 8.3)
• H2SO4 Additions to Alkenes (Section 8.4)
• H2O Additions to Alkenes (Section 8.5)
• Oxymercuration/Demurcuration (Section 8.6)
• Hydroboration/Oxidation (Section 8.7)
• Addition of Br2 and Cl2 to Alkenes (Section 8.12)
• Stereochemistry of Dihalide Additions (Section 8.13)
• Halohydrin Formation [Net Addition of X-OH] (Section 8.14)
• Divalent Carbon Compounds: Carbenes (Section 8.15)
• Oxidations of Alkenes (Sections 8.16-8.17)
• Additions to Alkynes (Sections 8.18-8.19)
• Oxidative Cleavage of Alkynes (Section 8.20)
• Applications in Synthesis (Section 8.21)
2. Addition Reactions: Addition to Alkenes
Addition
C C A B A C C B
• Have Already Looked at Addition of H2 (Hydrogenation)
• Will Now Add Additional Reagents to Our Arsenal
HX (I, Br, Cl) Br2
H2SO4 Cl2
H2O I2
3. Why Do Additions to Alkenes Work?
• Conversion of π Bond to 2 σ Bonds Typically Energy Favored
• Two σ Bonds Higher Energy than One π + One σ
• Overall Process is thus Typically Exothermic
• π Electrons are Exposed (ABOVE and BELOW sp2 Plane)
• π Bonds Good at Capturing Electrophiles (H+, Lewis Acids, X2)
• Metal Ions With Vacant Orbitals Also Good Electrophiles
• Let’s Look at the Addition Reaction of a Hydrogen Halide
4. Addition Reactions: HX to Alkenes
H Br
C C H Br H Br
• General Order of HX Reactivity:
HI > HBr > HCl > HF
• Usually Dissolved in Solvent (CH3CO2H, CH2Cl2)
• Can be Bubbled Through Solution as a Gas
• Addition of HCl not Generally Useful (Works w/ Silica Gel)
5. Addition Reactions: HBr to Alkenes
H Br
C C H Br H Br
• π Bond (Nucleophile) Protonate Carbocation Intermediate
• Carbocation Captured by Br¯ (Nucleophile) HBr Added
• HBr (or other HX) Addition in Two Overall Steps
• H+ and Carbocation are the Respective Electrophiles
• This is a SYMMETRIC Alkene ASYMMETRIC ALKENES?
6. Markovnikov’s Rule: HBr to Alkenes
Br
HBr
Br
o
CH2Cl2, 0 C
MAJOR MINOR (TRACE)
• 2-Bromopropane is Major Product
• Only Very Small Amount of 1-Bromopropane Observed
• True With Other Alkenes
Br
HBr
Br
o
CH2Cl2, 0 C
MAJOR MINOR (TRACE)
7. Markovnikov’s Rule: Why?
Br
HBr
Br
o
CH2Cl2, 0 C
MAJOR MINOR (TRACE)
• Product Distribution Explained When Looking at Intermediates
• Recall Discussion of Carbocation Stability (2° > 1°)
• Major Product Formed From More Stable C+ Intermediate
H
H
H Br
Less Stable More Stable
Carbocation Carbocation
8. Markovnikov’s Rule: C+ Stability
H
H
H Br
Less Stable More Stable
Carbocation Carbocation
• We Know 2° Carbocations More Stable Than 1°
• Major Product Formed From More Stable C+ Intermediate
• Means TS in 2° Carbocation Pathway Lower in Energy
• Lower Energy of Activation
• Activation Energies in 1° Carbocation Pathways Much Larger
9. Markovnikov’s Rule: Summary
MARKOVNIKOV’S RULE:
In the ionic additions of an unsymmetrical
reagent to a double bond, the positive portion
of the adding reagent attaches itself to a
carbon atom of the double bond so as to yield
the MORE STABLE CARBOCATION as an
INTERMEDIATE Cl
Cl
I I
I Cl
δ δ
Recall Bond Polarization: I Cl
This Addition “Preference” is Called REGIOSELECTIVITY
10. Stereochemistry in Ionic Additions
Br Br
Top Capture
H
H
CH3
H Br
+
CH3 CH3
Bottom Capture H
Br
Br
• Just as We Saw in SN1: C+ Has TWO FACES
• Top and Bottom Attack Give Two Stereochemical Products
• R and S Enantiomers Formed as a Racemic Mixture (50:50)
11. H2SO4 Addition to Alkenes
O
O H O S O
H O S O H O
H H OSO3H
O
C C C C
• Must Add COLD Sulfuric Acid; Form Alkyl Hydrogen Sulfates
• Regioselective Reaction: Obeys Markovnikov’s Rule
• Note Mechanistic Similarities w/ HX Addition to Alkenes
12. Alcohols From Alkyl Hydrogen Sulfates
H OSO3H H OH
H2 O
∆
• HYDROLYSIS Reaction of Alkyl Hydrogen Sulfate
• Simply Heat the Sulfate in Water
• Net Reaction is Markovnikov Addition of H2O to Alkene
• Used in One Industrial Ethanol Making Process
13. Addition of H2O to Alkenes: Hydration
H3 O
C C + HOH
H OH
• HYDRATION Reaction of an Alkene
• Acid Catalyzed Addition of H2O Across Double Bond
• Net Reaction is Markovnikov Addition of H2O to Alkene
• We’ve Seen a Similar Reaction: Acid Catalyzed Dehydration
• Carbocation Rearrangements Possible w/ Dehydration Reactions
What is the MECHANISM for this reaction? Know this!
14. Oxymercuration-Demercuration
OXYMERCURATION:
THF
C C + H2O + Hg(OAc)2
OH HgOAc
DEMERCURATION:
NaOH, NaBH4
OH HgOAc OH H
• Net Reaction: Markovnikov Addition of H2O to Alkene
• Both Reactions Quite Rapid; Alcohol Yields Usually > 90%
• NaBH4: Sodium Borohydride “H¯” Delivering Agent
15. Oxymercuration-Demercuration (2)
H H H H
H H
Hg(OAc)2 NaOH, NaBH4
C C Pr H Pr H
THF/H2O
Pr H OH HgOAc OH H
Me OH Me OH
HgOAc H
Hg(OAc)2 NaOH, NaBH4
THF/H2O
H H
• Added Benefit of Oxymercuration/Demercuration:
C+ REARRANGEMENTS Seldomly Observed
Consider Example Seen on Next Slide
16. Oxymercuration-Demercuration (3)
1. Hg(OAc)2,
THF/H2O
2. NaOH, NaBH4
OH
HgOAc HgOAc
Hg Stabilization
• Would Expect 2° Carbocation to Rearrange to 3°
• Added C+ Stabilization from Hg Atom Prevents Rearrangment
• Useful Hydration Process for Avoiding Skeletal Migrations
17. Hydroboration—Oxidation Reactions
BH3 : THF H2O2, NaOH
(CH3CH2CH2)3B OH
Hydroboration Oxidation
• Hydroboration: Addition of H and B to Alkene
• Neutral Boron has 3 Coordination Sites
Get Trialkyl Boranes as an Intermediate (Tripropylborane)
• Oxidation: H2O2, NaOH Oxidize to Trialkylborate Ester
• Oxidation Followed by a Hydrolysis, Cleaves Borate Ester
• ANTI-MARKOVNIKOV Product (Good for 1° Alcohols!)
18. Hydroboration—Oxidation Reactions (2)
We Mentioned anti-Markovnikov Regiochemistry
Reaction also Proceeds with SYN Stereochemistry
Me
Me
1. BH3 : THF H
2. H2O2, NaOH H
OH
H
H and OH Delivered anti-Markovnikov to the
SAME FACE of the π Bond
Sections 8.8 and 8.9 Deal w/ Mechanistic Aspects. This is
Interesting, but is NOT Testable Material (You May Omit)
19. Addition of Cl2 and Br2 to Alkenes
Cl2 H3CHC CHCH3
H3CHC CHCH3
-9 oC
Cl Cl
Cl2 H3CH2CHC CH2
H3CH2CHC CH2
-9 oC
Cl Cl
Br
Br2 H + Enantiomer
-5 oC H
Br
• Obtain Vicinal Dihalides as Reaction Products
• Want to use a Non-Nucleophilic Solvent (Due to Intermediate)
Important to Run Reactions in Dark (Avoid Radicals)
20. General Mechanism of Dihalide Addition
Br
Br
Br
-Br- Br
C C
Br
Br
• Intermediate is a BROMONIUM ION (in Br2 Case)
• Nucleophilic Solvents Can Capture (Open) Bromonium Ion
Bromonium Ion Opening is SN2 Anti Addition of Br2
21. Stereochemistry of Dihalide Additions
• Can Open Symmetric Bromonium Ions at Either Carbon
• Always (for now) Anti (Trans) Addition of X2
• Reaction Products Are Enantiomers
• Racemic Mixtures (50:50) in Symmetric Bromonium Ions
• Will Get Excess of One Enantiomer in Asymmetric Cases
• Stereospecific Reactions: One Stereoiomeric Form of the
Starting Material Reacts in Such a Way to Form a
Specific Stereoisomeric Form of the Product
22. Halohydrin Formation
Br
Br
Br
-Br- -H+ Br
C C
HO
H2O
• Intermediate is Still a BROMONIUM ION (in Br2 Case)
• Nucleophilic Solvents Can Capture (Open) Bromonium Ion
H2O Opens the Bromonium Ion; Another H2O Deprotonates
Product is Halohydrin Net X-OH Addition to Alkene
Still Can Get Stereoisomeric Products (Open Either End)
23. Divalent Carbon Compounds: Carbenes
Heat or Light
CH2 N N CH2 + N N
Diazomethane Methylene
(A Carbene)
• Common Way of Generating Carbenes (Divalent Carbon)
• Diazomethane: 3 Resonance Structures (Draw Others??)
• Carbenes are Highly Reactive Species; Short-Lived
• Excellent Utility is in the Synthesis of Cyclopropanes
• Let’s Look at Some Reactions Making Use of Carbenes
24. Divalent Carbon Compounds: Carbenes
C C + CH2 C C
C
H2
Cl
KOC(CH3)3
CHCl3 Cl
CH2I2, Zn(Cu)
• Halogen Substituted Carbenes from Haloforms (CHCl3, etc.)
• Last Reaction is Called the “Simmons-Smith” Reaction
25. Oxidation: Syn Dihydroxylation
OH
1. OsO4, pyridine
OH
2. Na2SO3/H2O
Propene 1,2-propanediol
(propylene glycol)
• C=C is Oxidized by OsO4
• Addition of Hydroxyl Groups Proceeds w/ SYN Stereochemistry
• Can Also use KMNO4 (More Powerful, May Cleave Diol)
• If Using KMNO4, Want COLD Reaction Temperatures
• OsO4 is Expensive; Can Use Catalytically if NMO is Added
26. Oxidation: Syn Dihydroxylation (2)
OsO4, 25 oC
Pyridine O O
Os
O O
Osmate Ester
• Syn Addition Due to 5-Centered Transition State
• Transition State Same for KMNO4 Oxidations
• Cleavage of Osmate Ester Does Not Change C-O Stereochem
27. Oxidative Cleavage of Alkenes
O
KMnO4, NaOH
2
H2O, ∆ O
1. KMnO4, NaOH O
+ O C O
∆
2. H3O+
• Diol Believed to be Intermediate in Cleavage Reaction
• Unsubstituted Alkene Carbons Oxidized to Carbon Dioxide
• Monosubstituted Alkene Carbons Oxidized to Carboxylates
• Disubstituted Alkene Carbons Oxidized to Ketones
28. How You May See Oxidative Cleavage
An Unknown Alkene (C8H16) Gives Two
Products When Treated w/ Hot KMnO4:
1. KMnO4, H2O OH
C8H16 NaOH, ∆ +
2. H3O+
O O
The Products are a Carboxylic Acid and a Ketone, So Our Alkene Must Be
Trisubstituted. We Don't Know if it is CIS or TRANS, but we Can Put the
Rest of the Structure Together:
or
29. Ozonolysis of Alkenes
Me Me Me O
1. O3, CH2Cl2, -78 oC O +
2. Zn/HOAc Me H
Et Et
O
Me
1. O3, CH2Cl2, -78 oC H
Me
2. Zn/HOAc
O
• Milder Conditions than Treating w/ KMnO4
• “Workup” w/ Zn/HOAc Oxidative Cleavage (Ald and Ket)
• Go Through Exceptionally Unstable Intermediate (Ozonide)
30. Dihalide Addition To Alkynes
Me Br Br Br
Br2 Br2
Me Me Me Me
CCl4 CCl4
Br Me Br Br
Me Cl Cl Cl
Cl2 Cl2
Me Me Me Me
CCl4 CCl4
Cl Me Cl Cl
• Addition Reactions, Just as in Alkenes (adds Once or Twice)
• Anti Additions, First Product Usually a Trans Dihaloalkene
• Can Get Relatively Good Trans Dihaloalkene Yields (1 eq X2)
31. Addition of HX to Alkynes
Me Br H Br
HBr HBr Me Me
Me Me
H Me H Br
geminal dihaloalkane
• Addition Reactions, Just as in Alkenes (adds Once or Twice)
• Final Product Typically Geminal Dihaloalkene
• Both Additions Follow Markovnikov’s Rule (explains gem.)
• Alumina Accelerates Reaction Rate (as seen w/ Alkenes)
32. Oxidative Cleavage of Alkynes
O O
1. O3, CH2Cl2,
Me Et +
2. Zn/HOAc
Me OH Et OH
O O
1. O3, CH2Cl2,
i
Pr Ph +
2. Zn/HOAc
i
Pr OH Ph OH
O O
1. KMnO4, NaOH
Me Et +
2. HOAc
Me OH Et OH
• Can Use Either Ozonolysis or KMnO4 as with Alkenes
• Products of the Oxidative Cleavage are Carboxylic Acids
33. Anti-Markovnikov HBr Addition
HBr Br
peroxides
Me Br
HBr
Me H
peroxides
H H
• Addition of Peroxides (ROOR) ANTI-MARKOVNIKOV
• Goes Through a Radical Mechanism (Chapter 10)
• Right Now Focus on Regiochemistry (Know the Reaction)