The document summarizes the steps taken in a synthesis of thymol from para-cymene. The key steps involve:
1. Nitrating para-cymene to form nitrocymene, then reducing nitrocymene to form cymidine.
2. Sulfonating cymidine to form cymidine-sulfonic acid.
3. Converting cymidine-sulfonic acid to diazocymene-sulfonic acid, then to cymylhydrazine-p-sulfonic acid upon treatment with sodium bisulfite.
4. Removing the hydrazine group from cymylhydrazine-p-
This document summarizes the propylene oxide production process. It produces 29,000 MT/PA of propylene oxide through a process involving chlorhydrin production, saponification, and purification. Key steps include reacting propylene and chlorine to form chlorhydrin, saponifying the chlorhydrin with lime to form propylene oxide, and purifying the propylene oxide through distillation. Utilities like steam, water, and electricity are required and side products like dichloropropane are also produced.
The document describes organopolysiloxane nitriles, which are novel compounds that can be used as intermediates to produce amide and acid substituted polysiloxanes. The organopolysiloxane nitriles have the general formula R'RNCCH(CH2)xSiO, where R' is a methyl or hydrogen, N has a value of 1 to 3, and R is a monovalent hydrocarbon radical without aliphatic unsaturation. The compounds can be prepared by reacting an unsaturated nitrile with a chlorosilane or by condensing a chloromethylalkoxysilane with an ethyl cyanoacetate. Co-polymers of the silox
Power Plant Chemistry FEED WATER TREATMENTDilip Kumar
This document provides information on feed water treatment and corrosion control in power plants. It discusses the types of impurities found in feed water and how maintaining an alkaline pH and removing dissolved oxygen can minimize corrosion. It also outlines water quality guidelines and parameters for different types of plant systems. The objectives of chemical treatment are to reduce corrosion and prevent scale formation. Various chemical treatments used include volatile alkalis to control pH, hydrazine for oxygen removal, and phosphates for alkalinity and corrosion control.
The document describes improvements to the "oxo process" for producing oxygenated organic compounds from olefins using carbon monoxide, hydrogen, and a carbonylation catalyst. Specifically, it involves using a catalyst combination that is particularly effective for catalyzing the reaction. The oxo process typically involves three stages - an initial reaction of the olefin with carbon monoxide and hydrogen over a cobalt catalyst to produce aldehydes, removal of soluble metal compounds from the product, and then hydrogenation of the aldehydes to alcohols. The invention relates to improving the catalyst used in the first stage of the reaction.
The document describes a process for preparing alcohols by hydrogenating carboxylic acids or esters at elevated temperature and pressure in the presence of catalysts containing oxides of group IV and VI elements. Specifically, the hydrogenation is carried out at 250-400°C and 5-100 bar in the presence of primary or secondary alcohols, with a molar hydrogen to alcohol ratio of at most 800.
This document discusses water treatment for steam boilers. There are two main types of boilers - fire tube and water tube. Boilers are also classified by pressure as high or low. Boiler water treatment aims to control scale, corrosion and carryover. Key treatments include oxygen removal, pH control, phosphate for sludge conditioning, and neutralizing amines for condensate lines. Proper control of parameters like TDS, alkalinity and blowdown is important for effective treatment and boiler operation.
Steps to boiler chemical cleaning and treatment selectionSanjana Khound
Chemical cleaning of boiler usually consists of a combination of the following stages.
Mechanical Cleaning: Mechanical cleaning and water flushing can remove loose scale and other debris from the boiler through wiping, brushing, blowing, and friction method.
Alkaline Treatment: This treatment usually removes oil and hydrocarbons that might interfere with the dissolution of the scale by an acid solvent.
Solvent Cleaning: This is the process in which inhibited acid is used to remove scale from the boiler.
Neutralization & Passivation: This is designed to remove any last traces of iron oxide. In Neutralization & Passivation is executed by replacing the active metal with a well-passivated surfaces layer.
OXIDATION [PHARMACEUTICAL PROCESS CHEMISTRY]Shikha Popali
INTRODUCTION TO OXIDATION , WHICH IS PROCESS OF ADDITION OF OXYGEN TO THE COMPOUND IN RPOCESS CHEMISTRY AND LIQUID PHASE OXIDATION AND OTHER OXIDISING AGENTS ARE DISCUSSED.
This document summarizes the propylene oxide production process. It produces 29,000 MT/PA of propylene oxide through a process involving chlorhydrin production, saponification, and purification. Key steps include reacting propylene and chlorine to form chlorhydrin, saponifying the chlorhydrin with lime to form propylene oxide, and purifying the propylene oxide through distillation. Utilities like steam, water, and electricity are required and side products like dichloropropane are also produced.
The document describes organopolysiloxane nitriles, which are novel compounds that can be used as intermediates to produce amide and acid substituted polysiloxanes. The organopolysiloxane nitriles have the general formula R'RNCCH(CH2)xSiO, where R' is a methyl or hydrogen, N has a value of 1 to 3, and R is a monovalent hydrocarbon radical without aliphatic unsaturation. The compounds can be prepared by reacting an unsaturated nitrile with a chlorosilane or by condensing a chloromethylalkoxysilane with an ethyl cyanoacetate. Co-polymers of the silox
Power Plant Chemistry FEED WATER TREATMENTDilip Kumar
This document provides information on feed water treatment and corrosion control in power plants. It discusses the types of impurities found in feed water and how maintaining an alkaline pH and removing dissolved oxygen can minimize corrosion. It also outlines water quality guidelines and parameters for different types of plant systems. The objectives of chemical treatment are to reduce corrosion and prevent scale formation. Various chemical treatments used include volatile alkalis to control pH, hydrazine for oxygen removal, and phosphates for alkalinity and corrosion control.
The document describes improvements to the "oxo process" for producing oxygenated organic compounds from olefins using carbon monoxide, hydrogen, and a carbonylation catalyst. Specifically, it involves using a catalyst combination that is particularly effective for catalyzing the reaction. The oxo process typically involves three stages - an initial reaction of the olefin with carbon monoxide and hydrogen over a cobalt catalyst to produce aldehydes, removal of soluble metal compounds from the product, and then hydrogenation of the aldehydes to alcohols. The invention relates to improving the catalyst used in the first stage of the reaction.
The document describes a process for preparing alcohols by hydrogenating carboxylic acids or esters at elevated temperature and pressure in the presence of catalysts containing oxides of group IV and VI elements. Specifically, the hydrogenation is carried out at 250-400°C and 5-100 bar in the presence of primary or secondary alcohols, with a molar hydrogen to alcohol ratio of at most 800.
This document discusses water treatment for steam boilers. There are two main types of boilers - fire tube and water tube. Boilers are also classified by pressure as high or low. Boiler water treatment aims to control scale, corrosion and carryover. Key treatments include oxygen removal, pH control, phosphate for sludge conditioning, and neutralizing amines for condensate lines. Proper control of parameters like TDS, alkalinity and blowdown is important for effective treatment and boiler operation.
Steps to boiler chemical cleaning and treatment selectionSanjana Khound
Chemical cleaning of boiler usually consists of a combination of the following stages.
Mechanical Cleaning: Mechanical cleaning and water flushing can remove loose scale and other debris from the boiler through wiping, brushing, blowing, and friction method.
Alkaline Treatment: This treatment usually removes oil and hydrocarbons that might interfere with the dissolution of the scale by an acid solvent.
Solvent Cleaning: This is the process in which inhibited acid is used to remove scale from the boiler.
Neutralization & Passivation: This is designed to remove any last traces of iron oxide. In Neutralization & Passivation is executed by replacing the active metal with a well-passivated surfaces layer.
OXIDATION [PHARMACEUTICAL PROCESS CHEMISTRY]Shikha Popali
INTRODUCTION TO OXIDATION , WHICH IS PROCESS OF ADDITION OF OXYGEN TO THE COMPOUND IN RPOCESS CHEMISTRY AND LIQUID PHASE OXIDATION AND OTHER OXIDISING AGENTS ARE DISCUSSED.
The document discusses chemical cleaning agents and processes. It covers acid cleaning agents like hydrochloric acid, phosphoric acid, sulfamic acid, and nitric acid. It also discusses chelating agents like EDTA and citric acid. Key details provided include effective dosages, cleaning temperatures, advantages and disadvantages of different chemicals, and safety considerations. The document aims to educate on selecting the appropriate chemical cleaning system based on the application and deposits.
Basic Thermal Power Plant Chemistry, for Operational Staff.Syed Aqeel Ahmed
The document provides an overview of water chemistry training for power plant operators. It discusses the importance of controlling water quality to prevent scale, corrosion, and biological growth in power plant systems. It covers external water treatment processes like clarification, filtration, and desalination. It also summarizes internal water treatment including oxygen scavenging, pH control, and use of chemicals like hydrazine. Key water quality parameters that are monitored like conductivity, pH, chlorides, and sodium are explained. The document provides troubleshooting guidance and emphasizes the importance of detecting condenser leakage to prevent contamination of boiler water.
After Cation Conductivity (ACC) is a measurement of the electrolytic conductivity of a water sample after it has passed through a cation exchange resin column. It detects low levels of anion contaminants like chlorides and sulfates. ACC is commonly measured on main steam, reheat steam, condensate, feedwater, and boiler drum samples in power plants. It is important because power plant steam and water systems must maintain high purity to prevent corrosion and deposition. The cation exchange column increases the conductivity contribution from contaminant salts, amplifying the sensitivity of the conductivity analyzer.
Diammonium phosphate (DAP) is a white, water-soluble powder with the chemical formula (NH4)2HPO4. It has a density of 1.619 g/cm3 and melts at 155°C. DAP is manufactured using ammonia, phosphoric acid, sulfuric acid, and urea through a process involving granulation, drying, screening, and packaging in multi-wall bags. It is commonly used as a nitrogen-phosphate fertilizer to temporarily increase soil pH.
Naphthalene is an aromatic hydrocarbon consisting of two fused benzene rings. It is isolated from coal tar, where it makes up 6-10% of the fraction. Naphthalene crystallizes as white plates with a strong odor. It sublimes readily and is insoluble in water but soluble in organic solvents. Naphthalene undergoes substitution and addition reactions similarly to benzene, though it is somewhat less aromatic. Resonance structures show that the C1-C2 bond has more double bond character, making it shorter than the C2-C3 bond. Naphthalene has several industrial and medical uses including in the production of naphthols, dyes, beta blocker drugs
This document presents methods for analyzing various fermented products such as wine, spirits, beer, and vinegar. It discusses spectrophotometric methods for determining tannins and total acidity in wines. It also describes procedures for determining extracts, sulphur dioxide, ethyl alcohol, total acidity, and methyl alcohol content. The methods include titration, distillation, and spectrophotometric techniques. Standards from IS and AOAC are referenced for alcohol analysis methods.
This document discusses ammonia, including its physical, chemical, and structural properties. It describes the Haber-Bosch process for producing ammonia through the reaction of nitrogen and hydrogen gases. Modern plants first convert natural gas to hydrogen, then combine it with nitrogen to make ammonia. The main industrial uses of ammonia are in fertilizer production and household cleaning. Secondary uses include refrigeration and as a lifting gas. In the laboratory, ammonia is used to make other nitrogen compounds and as a solvent. Exposure to high levels of ammonia can harm the environment and cause health issues in humans and animals such as increased blood pressure, mental effects, and damage to the esophagus from ingestion.
Description of nitric acid manufacturing processSameer Pandey
Nitric acid is manufactured through the Ostwald process which involves oxidizing ammonia with air over a platinum-rhodium catalyst at 850°C to produce nitric oxide, which is then oxidized to nitrogen dioxide and absorbed in water to form nitric acid. The manufacturing process can operate at single or dual pressures and involves filtering air, oxidizing and absorbing NO to form weak nitric acid, and concentrating the weak acid through extractive distillation with sulfuric acid to produce strong nitric acid at 99% concentration. Emissions are controlled by further absorbing tail gases to produce sodium nitrate and nitrite or with wet scrubbers.
The document provides procedures for microscale synthesis of several organic compounds including aspirin, E-benzal, and azodyes. Microscale chemistry uses small quantities of chemicals to reduce waste and improve safety. It describes basic microscale equipment like conical vials, air condensers, Craig tubes for recrystallization, and pipettes. The aspirin synthesis involves reacting salicylic acid with acetyl chloride to form aspirin, which is then recrystallized. The E-benzal synthesis reacts benzaldehyde with hydroxylamine hydrochloride in the presence of sodium hydroxide.
This document describes methods for analyzing fermentation products such as wine, spirits, and beer. It discusses determining various analytes including tannins, extracts, sulphur dioxide, ethyl alcohol content, total acidity, and methyl alcohol. Spectrophotometric and gas chromatography methods are provided for measuring methyl alcohol. The document also outlines procedures for common assays such as using a spectrophotometer to generate a standard curve for tannin quantification and titrating samples with sodium hydroxide to determine total acidity.
A Relationship Between Calcium Phosphate And Silica Fouling In Wastewater Ro ...momalki
This paper was presented at AMTA and the IDA. It shows that allowing calcium phosphate scale to form will result in silica scaling. It also compares the performance of different antiscalants in control of calcium phosphate.
The document discusses boiler feed water chemistry. It describes various impurities found in water sources and different pre-treatment methods to remove them, such as clarification, filtration, ion exchange and degasification. It also covers internal boiler water treatment using chemicals like soda ash and phosphates to precipitate dissolved salts and prevent scaling. Maintaining proper water chemistry parameters and controlling corrosion is important for boiler reliability and efficiency.
This document describes a method for purifying concentrated aqueous solutions of inorganic salts such as zinc chloride, calcium chloride, and magnesium chloride. The method involves adding an excess of a water-soluble persulfate at a temperature of at least 50°C to precipitate impurities such as iron, manganese, and copper. The precipitate is filtered out and the filtrate is boiled to decompose remaining persulfate. Zinc dust is added to plate out any remaining copper, and the solution is filtered and neutralized to obtain a purified solution free of impurities that could discolor or otherwise affect polymers made using the solution.
This document describes a method for purifying concentrated aqueous solutions of inorganic salts such as zinc chloride, calcium chloride, and magnesium chloride. The method involves adding an excess of a water-soluble persulfate at a temperature of at least 50°C to precipitate impurities such as iron, manganese, and copper. The precipitate is filtered out and the filtrate is boiled to decompose remaining persulfate. Zinc dust is added to plate out any remaining copper, and the solution is filtered and neutralized to obtain a purified solution free of impurities that could discolor or otherwise affect polymers made using the solution.
This document discusses methods for removing acidic components like H2S and CO2 from hydrocarbon streams. It begins by categorizing the available methods as those relying on chemical reaction, absorption, or adsorption. Safety precautions are outlined when dealing with H2S and CO2. Common contaminants that require removal are then listed, along with general considerations for gas treating systems including inlet separation, filtration, and identification of amine degradation products.
Quinoxaline as a potent heterocyclic moietyiosrphr_editor
The IOSR Journal of Pharmacy (IOSRPHR) is an open access online & offline peer reviewed international journal, which publishes innovative research papers, reviews, mini-reviews, short communications and notes dealing with Pharmaceutical Sciences( Pharmaceutical Technology, Pharmaceutics, Biopharmaceutics, Pharmacokinetics, Pharmaceutical/Medicinal Chemistry, Computational Chemistry and Molecular Drug Design, Pharmacognosy & Phytochemistry, Pharmacology, Pharmaceutical Analysis, Pharmacy Practice, Clinical and Hospital Pharmacy, Cell Biology, Genomics and Proteomics, Pharmacogenomics, Bioinformatics and Biotechnology of Pharmaceutical Interest........more details on Aim & Scope).
1) The document describes new therapeutically active derivatives of barbituric acid having the general formula bicyclo l 1 2 3 l octenyl-( 2)-C-X C = A OC-N-H.
2) Eight examples are provided for preparing various bicyclo-octenyl barbituric acids and their derivatives through condensation reactions between functional derivatives of bicyclo-octenyl cyanoacetic or malonic acid and urea or related compounds.
3) The resulting products include 5-(bicyclo-octenyl)-5-methyl barbituric acid and salts thereof, which form colorless needles with a melting point of 266 C.
This document discusses the production of ammonium phosphate fertilizers. It describes that monoammonium phosphate (MAP) is produced with an ammonia to phosphoric acid ratio of 0.6, yielding a product with 11-12% nitrogen. Diammonium phosphate (DAP) is produced with a ratio of 1.4, containing 16-18% nitrogen. The process involves neutralizing phosphoric acid with ammonia in continuous reactors, then granulating and drying the slurry to produce the final fertilizer products.
Ammonia is a common toxicant that is derived from wastes, fertilizers, and natural processes. It has a long history dating back to its discovery in 1774. Ammonia has many industrial uses including in fertilizer production, refrigeration, textile processing, and steel manufacturing. It is highly soluble in water and forms ammonium hydroxide which acts as a weak base. Ammonia's properties make it useful as an industrial solvent.
Di-ammonium phosphate (DAP) is the world’s most widely used phosphorus fertilizer. It’s made from two common constituents in the fertilizer industry, and its relatively high nutrient content and excellent physical properties make it a popular choice in farming and other industries
El GenBank es una base de datos que almacena secuencias de nucleótidos y proteínas de distintas especies. Los usuarios pueden buscar información genética ingresando nombres de especies o códigos de acceso. BioEdit es un programa gratuito para editar y alinear secuencias descargadas de GenBank. Permite cargar múltiples secuencias y alinearlas manualmente insertando gaps o automáticamente usando ClustalW.
The document discusses chemical cleaning agents and processes. It covers acid cleaning agents like hydrochloric acid, phosphoric acid, sulfamic acid, and nitric acid. It also discusses chelating agents like EDTA and citric acid. Key details provided include effective dosages, cleaning temperatures, advantages and disadvantages of different chemicals, and safety considerations. The document aims to educate on selecting the appropriate chemical cleaning system based on the application and deposits.
Basic Thermal Power Plant Chemistry, for Operational Staff.Syed Aqeel Ahmed
The document provides an overview of water chemistry training for power plant operators. It discusses the importance of controlling water quality to prevent scale, corrosion, and biological growth in power plant systems. It covers external water treatment processes like clarification, filtration, and desalination. It also summarizes internal water treatment including oxygen scavenging, pH control, and use of chemicals like hydrazine. Key water quality parameters that are monitored like conductivity, pH, chlorides, and sodium are explained. The document provides troubleshooting guidance and emphasizes the importance of detecting condenser leakage to prevent contamination of boiler water.
After Cation Conductivity (ACC) is a measurement of the electrolytic conductivity of a water sample after it has passed through a cation exchange resin column. It detects low levels of anion contaminants like chlorides and sulfates. ACC is commonly measured on main steam, reheat steam, condensate, feedwater, and boiler drum samples in power plants. It is important because power plant steam and water systems must maintain high purity to prevent corrosion and deposition. The cation exchange column increases the conductivity contribution from contaminant salts, amplifying the sensitivity of the conductivity analyzer.
Diammonium phosphate (DAP) is a white, water-soluble powder with the chemical formula (NH4)2HPO4. It has a density of 1.619 g/cm3 and melts at 155°C. DAP is manufactured using ammonia, phosphoric acid, sulfuric acid, and urea through a process involving granulation, drying, screening, and packaging in multi-wall bags. It is commonly used as a nitrogen-phosphate fertilizer to temporarily increase soil pH.
Naphthalene is an aromatic hydrocarbon consisting of two fused benzene rings. It is isolated from coal tar, where it makes up 6-10% of the fraction. Naphthalene crystallizes as white plates with a strong odor. It sublimes readily and is insoluble in water but soluble in organic solvents. Naphthalene undergoes substitution and addition reactions similarly to benzene, though it is somewhat less aromatic. Resonance structures show that the C1-C2 bond has more double bond character, making it shorter than the C2-C3 bond. Naphthalene has several industrial and medical uses including in the production of naphthols, dyes, beta blocker drugs
This document presents methods for analyzing various fermented products such as wine, spirits, beer, and vinegar. It discusses spectrophotometric methods for determining tannins and total acidity in wines. It also describes procedures for determining extracts, sulphur dioxide, ethyl alcohol, total acidity, and methyl alcohol content. The methods include titration, distillation, and spectrophotometric techniques. Standards from IS and AOAC are referenced for alcohol analysis methods.
This document discusses ammonia, including its physical, chemical, and structural properties. It describes the Haber-Bosch process for producing ammonia through the reaction of nitrogen and hydrogen gases. Modern plants first convert natural gas to hydrogen, then combine it with nitrogen to make ammonia. The main industrial uses of ammonia are in fertilizer production and household cleaning. Secondary uses include refrigeration and as a lifting gas. In the laboratory, ammonia is used to make other nitrogen compounds and as a solvent. Exposure to high levels of ammonia can harm the environment and cause health issues in humans and animals such as increased blood pressure, mental effects, and damage to the esophagus from ingestion.
Description of nitric acid manufacturing processSameer Pandey
Nitric acid is manufactured through the Ostwald process which involves oxidizing ammonia with air over a platinum-rhodium catalyst at 850°C to produce nitric oxide, which is then oxidized to nitrogen dioxide and absorbed in water to form nitric acid. The manufacturing process can operate at single or dual pressures and involves filtering air, oxidizing and absorbing NO to form weak nitric acid, and concentrating the weak acid through extractive distillation with sulfuric acid to produce strong nitric acid at 99% concentration. Emissions are controlled by further absorbing tail gases to produce sodium nitrate and nitrite or with wet scrubbers.
The document provides procedures for microscale synthesis of several organic compounds including aspirin, E-benzal, and azodyes. Microscale chemistry uses small quantities of chemicals to reduce waste and improve safety. It describes basic microscale equipment like conical vials, air condensers, Craig tubes for recrystallization, and pipettes. The aspirin synthesis involves reacting salicylic acid with acetyl chloride to form aspirin, which is then recrystallized. The E-benzal synthesis reacts benzaldehyde with hydroxylamine hydrochloride in the presence of sodium hydroxide.
This document describes methods for analyzing fermentation products such as wine, spirits, and beer. It discusses determining various analytes including tannins, extracts, sulphur dioxide, ethyl alcohol content, total acidity, and methyl alcohol. Spectrophotometric and gas chromatography methods are provided for measuring methyl alcohol. The document also outlines procedures for common assays such as using a spectrophotometer to generate a standard curve for tannin quantification and titrating samples with sodium hydroxide to determine total acidity.
A Relationship Between Calcium Phosphate And Silica Fouling In Wastewater Ro ...momalki
This paper was presented at AMTA and the IDA. It shows that allowing calcium phosphate scale to form will result in silica scaling. It also compares the performance of different antiscalants in control of calcium phosphate.
The document discusses boiler feed water chemistry. It describes various impurities found in water sources and different pre-treatment methods to remove them, such as clarification, filtration, ion exchange and degasification. It also covers internal boiler water treatment using chemicals like soda ash and phosphates to precipitate dissolved salts and prevent scaling. Maintaining proper water chemistry parameters and controlling corrosion is important for boiler reliability and efficiency.
This document describes a method for purifying concentrated aqueous solutions of inorganic salts such as zinc chloride, calcium chloride, and magnesium chloride. The method involves adding an excess of a water-soluble persulfate at a temperature of at least 50°C to precipitate impurities such as iron, manganese, and copper. The precipitate is filtered out and the filtrate is boiled to decompose remaining persulfate. Zinc dust is added to plate out any remaining copper, and the solution is filtered and neutralized to obtain a purified solution free of impurities that could discolor or otherwise affect polymers made using the solution.
This document describes a method for purifying concentrated aqueous solutions of inorganic salts such as zinc chloride, calcium chloride, and magnesium chloride. The method involves adding an excess of a water-soluble persulfate at a temperature of at least 50°C to precipitate impurities such as iron, manganese, and copper. The precipitate is filtered out and the filtrate is boiled to decompose remaining persulfate. Zinc dust is added to plate out any remaining copper, and the solution is filtered and neutralized to obtain a purified solution free of impurities that could discolor or otherwise affect polymers made using the solution.
This document discusses methods for removing acidic components like H2S and CO2 from hydrocarbon streams. It begins by categorizing the available methods as those relying on chemical reaction, absorption, or adsorption. Safety precautions are outlined when dealing with H2S and CO2. Common contaminants that require removal are then listed, along with general considerations for gas treating systems including inlet separation, filtration, and identification of amine degradation products.
Quinoxaline as a potent heterocyclic moietyiosrphr_editor
The IOSR Journal of Pharmacy (IOSRPHR) is an open access online & offline peer reviewed international journal, which publishes innovative research papers, reviews, mini-reviews, short communications and notes dealing with Pharmaceutical Sciences( Pharmaceutical Technology, Pharmaceutics, Biopharmaceutics, Pharmacokinetics, Pharmaceutical/Medicinal Chemistry, Computational Chemistry and Molecular Drug Design, Pharmacognosy & Phytochemistry, Pharmacology, Pharmaceutical Analysis, Pharmacy Practice, Clinical and Hospital Pharmacy, Cell Biology, Genomics and Proteomics, Pharmacogenomics, Bioinformatics and Biotechnology of Pharmaceutical Interest........more details on Aim & Scope).
1) The document describes new therapeutically active derivatives of barbituric acid having the general formula bicyclo l 1 2 3 l octenyl-( 2)-C-X C = A OC-N-H.
2) Eight examples are provided for preparing various bicyclo-octenyl barbituric acids and their derivatives through condensation reactions between functional derivatives of bicyclo-octenyl cyanoacetic or malonic acid and urea or related compounds.
3) The resulting products include 5-(bicyclo-octenyl)-5-methyl barbituric acid and salts thereof, which form colorless needles with a melting point of 266 C.
This document discusses the production of ammonium phosphate fertilizers. It describes that monoammonium phosphate (MAP) is produced with an ammonia to phosphoric acid ratio of 0.6, yielding a product with 11-12% nitrogen. Diammonium phosphate (DAP) is produced with a ratio of 1.4, containing 16-18% nitrogen. The process involves neutralizing phosphoric acid with ammonia in continuous reactors, then granulating and drying the slurry to produce the final fertilizer products.
Ammonia is a common toxicant that is derived from wastes, fertilizers, and natural processes. It has a long history dating back to its discovery in 1774. Ammonia has many industrial uses including in fertilizer production, refrigeration, textile processing, and steel manufacturing. It is highly soluble in water and forms ammonium hydroxide which acts as a weak base. Ammonia's properties make it useful as an industrial solvent.
Di-ammonium phosphate (DAP) is the world’s most widely used phosphorus fertilizer. It’s made from two common constituents in the fertilizer industry, and its relatively high nutrient content and excellent physical properties make it a popular choice in farming and other industries
El GenBank es una base de datos que almacena secuencias de nucleótidos y proteínas de distintas especies. Los usuarios pueden buscar información genética ingresando nombres de especies o códigos de acceso. BioEdit es un programa gratuito para editar y alinear secuencias descargadas de GenBank. Permite cargar múltiples secuencias y alinearlas manualmente insertando gaps o automáticamente usando ClustalW.
The Beilstein Handbook is a comprehensive compilation of information on organic compounds published in 503 volumes from 1918 to 1998. It covers the literature on organic chemistry up to 1959. The Handbook entries are in highly abbreviated German and provide textual descriptions of synthetic chemistry and data on compounds. Compounds are arranged systematically according to complex rules. Supporting materials in the library help users navigate the cryptic organization and terminology of the Beilstein Handbook.
El documento describe varias características humanas hereditarias como el color del cabello, la forma de las orejas y la coagulación de la sangre. Explica que algunas características como el color de piel son determinadas directamente por la herencia, mientras que otras como la estatura pueden verse influenciadas por el ambiente. También proporciona ejemplos de características dominantes y recesivas como el albinismo y el daltonismo.
Oxidation (Unit Process-1) Pharmaceutical Process Chemistry AikanGupta
The document discusses various types of oxidation reactions that are important in organic chemical synthesis, including dehydrogenation, peroxidation, introduction of oxygen atoms, and the oxidation of compounds containing sulfur, nitrogen, ethylenic bonds, and other functional groups. Examples are provided of industrial oxidation processes such as the production of vanillin, camphor, benzaldehyde, quinone, and dihydroxy fatty acids. Oxidizing agents and reaction conditions that influence the products are also described.
Diazotization titrations involve the reaction of primary aromatic amines with sodium nitrite in acidic solution to form unstable diazonium salts. This reaction can be used for both qualitative and quantitative analysis of compounds containing amino groups. The endpoint is detected using an external indicator like starch-iodide paper, which detects excess nitrous acid after all the aromatic amine has reacted. Some common compounds that can be assayed via diazotization titration include dapsone, sulphamethoxazole, and benzocaine.
Aromatic carboxylic acid preparation and reactionSayyedMohsina
The document describes methods for preparing aromatic carboxylic acids and reactions of aromatic carboxylic acids. Six methods are provided for preparing aromatic carboxylic acids: 1) oxidation of primary alcohols and aldehydes, 2) hydrolysis of nitriles, 3) carbonation of grignard reagents, 4) oxidation of carbon side chains, 5) hydrolysis of trichloromethyl groups on benzene nuclei, and 6) Friedel-Craft reactions. Reactions of aromatic carboxylic acids that are discussed include esterification, anhydride formation, acid halide formation, acid amide formation, decarboxylation, reduction, and electrophilic substitution in benzene rings
Diazotization TITRATION FOR PG NOTES VERY USEFUL prakash64742
The document discusses the principles and applications of diazotization titration. Diazotization involves the reaction of an aromatic primary amine with sodium nitrite in acidic medium to form a diazonium salt. The titration endpoint is determined using an indicator reaction that detects excess nitrous acid. Common applications described include assays of benzocaine, dapsone, and isocarboxazid which involve diazotization and detection of the endpoint with starch-iodide paper. Diazotization titration can be used to analyze many sulfa drugs and other pharmaceuticals containing aromatic amine groups.
This document describes several methods for quantitatively analyzing the components of organic compounds:
1. Carbon and hydrogen are estimated by burning the compound in oxygen and measuring the amount of water and carbon dioxide produced.
2. Nitrogen can be estimated using the Dumas or Kjeldahl methods, which involve heating the compound to produce nitrogen gas or ammonia for measurement.
3. Other elements like halogens, sulfur, phosphorus, and oxygen can be estimated through various oxidation and precipitation reactions to form compounds that can be weighed or titrated. Formulas are provided for calculating the percentage of each element from the experimental results.
This document summarizes a patent for manufacturing oximes of cycloaliphatic ketones. It describes a process where salts of thiosulphuric acid or polythionic acids are used as reducing agents in aqueous solution to produce oximes from water-soluble salts of secondary nitro-compounds in the cycloaliphatic series. The ratio used is 1 mole of nitro-compound to 1-1.5 moles of reducing agent salt. Examples provided demonstrate producing cyclohexanone oxime from nitrocyclohexane using sodium thiosulphate or sodium trithionate as the reducing agent. Yields of up to 92% of the oxime product are achieved.
Introduction and preparation of salicylic acid (1)yagnesh96
Salicylic acid is obtained from the bark of willow trees. It has the formula C7H6O3 and is a colorless crystalline organic acid. It was first discovered in 1839 by fusing salicylic aldehyde with potassium hydroxide. Salicylic acid is used externally to treat skin conditions like athlete's foot and warts, and is also used in acne treatments. It is synthesized commercially via the Kolbe-Lautemann process, which involves reacting phenol with sodium and carbon dioxide to produce sodium salicylate, then converting it to salicylic acid.
Introduction and preparation of salicylic acidyagnesh96
Salicylic acid is obtained from the bark of willow trees. It has the formula C7H6O3 and is a colorless crystalline organic acid. It was first discovered in 1839 by fusing salicylic aldehyde with potassium hydroxide. Salicylic acid is used externally to treat skin conditions like athlete's foot and warts, and is also used in acne treatments. It is synthesized commercially via the Kolbe-Lautemann process, which involves reacting phenol with sodium and carbon dioxide to produce sodium salicylate, then converting it to salicylic acid.
This document summarizes various reactions of carbohydrates including monosaccharides, disaccharides, and polysaccharides. It describes reactions such as reduction, oxidation, acetylation, methylation, hydrolysis, nitration, and color reactions used to identify different carbohydrate types. Specific monosaccharides discussed include glucose and fructose, and disaccharides discussed include sucrose and lactose. Polysaccharides discussed include starch and cellulose.
1. The experiment aims to perform the assay of Ibuprofen as per Indian Pharmacopoeia.
2. Ibuprofen is titrated with 0.1M sodium hydroxide solution using phenolphthalein as indicator.
3. The percentage purity of Ibuprofen is calculated based on the titration results.
Diamond has a giant covalent structure where each carbon atom is bonded to four other carbons, giving it properties like hardness and electrical insulation. It is used in cutting, jewelry due to its brilliance, and lasers. Graphite has layers of hexagonal carbon sheets bonded by van der Waals forces, making it soft and a conductor. It is used as a lubricant, in electrodes, and pencils. Hard water contains calcium and magnesium ions that form precipitates with soap. Temporary hardness can be removed by boiling or adding washing soda while permanent hardness requires ion exchange or distillation. Carbon forms oxides, is a reducing agent, and is important in combustion, fermentation, and the carbon cycle.
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1. June, 1923 THYMOL FROM PARA CYMENE. II 1489
yields. There was no evidence of the formation of the isomeric, higher-melting com-
pound, diphenyl-carbam-hydroxamic acid. The latter would have been formed, had
P-phenyl-hydroxylamine possessed any tendency to dissociate at the phenyl linking,
CaH8-NHOH.
Summary
Gvidence is submitted that supports the hypothesis of Jones and Hurd,
which stated that if the radical “R,” which “wanders” in a Beckmann
rearrangement, is potentially a free radical, the rearrangement occurs with
greater ease than otherwise. Diphenyl-carbam-hydroxamic acid deriva-
tives are discussed in this connection; diphenyl nitrogen is the “free
radical.”
Derivatives of monophenyl-carbam-hydroxamic acid (phenyl-hydroxy-
urea) could not be made to rearrange. The structure of carbanilido-
phenyl-hydroxy-urea is discussed and is preferred to the optional “di-
phenyl-hydroxy-biuret”structure. It is definitely proved that the assump-
tion that phenyl-hydroxy-urea dissociates into phenyl isocyanate and
hydroxylamine, is untenable.
Hydroxy-urea, and hydroxy-biuret are similarly discussed in this con-
nection.
A preliminary study has been made of the reaction between phenyl
isocyanate and monohydroxamic acids. The addition seems to be at the
a-hydroxylaminohydrogen rather than at the 6.
Additional data are obtained for the “diphenylamine reaction.”
A method is given which uses hydroxylamine sulfate in the preparation
of hydroxylamine in alcoholic solution, when hydroxylamine hydrochloride
is ?ot available.
URBANA,ILLINOIS
[CONTRIBUTIONFROM THE COLORLABORATORY,BUREAUOF CHEMISTRY,No. 671
A SYNTHESIS OF THYMOL FROM PARA CYMENE. I1
BYMAXPHILLIPS
Received November 28,1922
In an earlier article published from this Laboratory1a synthesis of thymol
from p-cymene was described. The yields obtained according to the
method outlined in that paper were far from satisfactory. In the present
article certain modifications and improvements in the process are given.
It will be noted from the results presented in this paper that, aside from
certain improvements in the yields of some of the intermediates used in this
synthesis, the present method differs primarily from the previous one in the
manner in which the amino group of cymidine-sulfonic acid is eliminated.
Instead of converting the cymidine-sulfonic acid into diazocymene-sulfonic
J. Ind. Eng. Chem,, 12, 733 (1920).
2. 1490 MAX PHILLIPS Vol. 45
acid and then removing the diazo group with alcohol and copper powder,
far better results were obtained by first converting the diazocymene-sulfonic
acid into cymylhydrazine-p-sulfonic acid and subsequently removing the
hydrazine group with boiling copper sulfate solution. The various steps
involved in the synthesis may be represented as follows:
CHI CHI
-NHa Has04
-+ 5 -+
H
(FefHCl) (Fuming)
CHa.CH.CHj CH3.CH.CH3 CHa.CH.CH3
@-Cymene Nitrocymene Cymidine
CH3
-"& HONO -N=N NaHS03 HCl
Ho&- -03s---() 1-----) -CH3.CH.CH3 ]CH, CH.CH3
Cymidine-sulfonic Acid Diazocymene-sulfonicAcid
Cymylhydrazine-p- Cymeme-3-sulfonic Thymol
Experimental Part
sulfonic Acid Acid
Preparation of Nitrocymene.-The nitrocymene used in all of this
work was prepared from p-cymene, obtained from so-called sulfite tur-
pentine, following the method of nitration fully described in a previgus
article.
Reduction of Nitrocymene to Cymidine.-One and six-tenths kg. of iron powder
and 1.5liters of boiling water were placed in an 8-liter flask, provided with an inverted
condenser. After the addition of 100 cc. of conc. hydrochloric acid, 1 kg. of nitro-
cymene was added slowly while the mixture was shaken. The addition of nitrocymene
was so regulated that the reaction mixture boiled quietly. Whenever the reaction be-
came tooviolent, it was moderated by coolingthe flask with water. When the reaction
was finished (shown by no further rise in temperature as the material was shaken) the
mixture was made alkaline with sodium hydroxide, and distilled in a current of steam.
The cyrnidine, which is lighter than water, was separated. The product thus obtained
was slightly contaminated with nitrocymene and other non-basic impurities. Although
these do not seriously interfere with the preparation of the next intermediate, neverthe-
less, it seemed desirable to remove them. Therefore, the crude cymidine was dissolved
in an excess of dil. sulfuric acid, and distilled in a current of steam until the non-basic
impurities were completely removed. The residue was made alkaline with sodium hy-
droxide and the cymidine distilled in a current of steam. The product was dried over
solid potassium hydroxide and used directly for the preparation of cymidine-sulfonic
acid. In some of the experiments, however, no effort was made to obtain the free base.
2 THISJOURXAL, 44, 1775 (1922)
3. June, 1923 THYMOL PROM PARA CYM$N$. I1 1491
but the residue from the steam distillation of the acid solution was concentrated on the
steam-bath, the cymidine sulfate collected on a filter, dried at 110' and used as such for
the preparation of cymidine-sulfonic acid. The yield of cymidine varied from 80 to
85% of that calculated.
Cymidine-sulfonic Acid.-One part by weight of cymidine was treated with the
calculated amount of sulfuric acid (d., 1.84)required for its conversion to cymidine acid
sulfate, and to this 2 parts of fuming sulfuric acid (2070 oleum) were added. The
addition of the oleum and cooling of the reaction mixture were so regulated that the
temperature did not exceed 140". The sulfonation mixture was then placed in an oil-
bath and heated to 130-140" with the thermometer in the reaction mixture. The
sulfonation was usually complete in from' 1/2 to 3/4 hour. The end of the reaction was
determined by diluting a small sample with water and making alkaline with sodium
hydroxide solution. If no cyrnidine separated the sulfonation was considered com-
plete. The reaction product was then cooled and poured into thrice its volume of ice
water. The cymidine-sulfonic acid separated as a grayish crystalline mass. After
standing for about 2 hours it was collected and purified by dissolvingit in a slight excess
of 20% solution of sodium hydroxide; this alkaline solution was boiled with animal char-
coal, and finally the cymidine-sulfonic acid was precipitated with an excess of sulfuric
acid. A white crystalline product was obtained. It was collected on a filter and dried
a t 120'. The yield was 80% of that calculated.
Cymylhydrazine-p-sulfonic Acid.-One mole (229 8.) of cymidine-sulfonic acid was
suspended in 1liter of water, and sodium hydroxide solution was added in slight excess.
The mixture was heated to dissolve the sulfonic acid. The calculated amount of
sodium nitrite (1mole) was added in the form of a 20% solution which had previously
been standardized against 0.1 N permanganate solution and the solution cooled to 0".
This mixture was then added slowly from a dropping funnel to a cold (0") dil. sulfuric
acid solution containing 150g. of sulfuricacid (d., 1.84) in 1000cc. of water. The solu-
tion was well stirred and the temperature throughout the diazotization maintained at 0"
to 4-5*. The diazocymene-sulfonic acid that separated was collected and added to a
cold (0' to $5") sodium bisulfite solution made by dissolving 300 g. of sodium sulfite in
3 liters of water and saturating this solution with sulfur dioxide. The orange-colored
solution was allowed to stand for 1hour at room temperature. It was then heated to
boiling, 500 cc. of hydrochloric acid (d., 1.19) was added, and the solution concentrated
on the steam-bath until crystallization of the cymylhydrazine-p-sulfonic acid began.
This compound was removed and dried a t 110"; yield, 70-75%.
Analyses. Subs., 0.2072,0.2111: COZ,0.3714, 0.3794;HzO, 0.1240, 0.1301. Subs.,
0.1571, 0.1576: BaSO4, 0.1500, 0.1576. Subs., 0.2116, 0.2478: 21.9 cc. of Nz (27",
767.2 mm.), 25.8 cc. (31°, 761.5 mm.). Calc. for CI~HI~OSNZS:C, 49.14; H, 6.60; N,
11.47; S, 13.12. Found: C, 48.89,49.01; H, 6.69, 6.89; N, 11.64, 11.46;S, 13.15, 13.29.
Cymylhydrazine-p-sulfonic acid is soluble in water but insoluble in alcohol or ether.
It melts with decomposition at 260".
The barium salt was prepared by boiling an aqueous solution of the acid with barium
carbonate.
Analyses. Subs., 0.6664, 0.6562: loss at 120" 0.0837, 0.0820. Calc. for (C10H15-
NzSO&Ba +5HZ0: HzO, 12.61. Found: 12.56,12.49.
Subs., anhyd., 0.3034, 0.3215: BaS04, 0.1126, 0.1195. Calc. for ( C ~ O H ~ ~ N ~ S O ~ ) ~ -
Ba: Ba, 22.01. Found: 21.84, 21.87.
Sodium Cymene-sulfonate.-One mole (244 9.) of cymylhydrazine-9-sulfonic acid
was dissolved in hot water and added in small portions to a boiling 10%solution of copper
sulfate. With each addition of the cymylhydrazine-p-sulfonic acid a rapid evolution of
nitrogen took place. Throughout the reaction an excess of copper sulfate was mnin-
It separated in the form of light yellow plates.
4. 1492 MAX PHILLIPS VOl. 45
taincd, as dctcrniincd by thc color of the solution. When no morc nitrogcn was given
off, thc copper oxidc was removcd by filtration and the filtrate treatcd with a slight
cxcess of barium hydroxidc solution. The barium sillfate and copper hydroxide wcrc
collected on a filter and thc filtratc freed from the cxccss of barium hydroxide with carbon
dioxide. The barium carbonatc was scparated and the filtratc trcatcd with sodium
carbonate solution until all the barium was prccipitatcd as barium carbonate. Thc
lattcr was rcmovcd by filtration and the filtrate cvaporatcd to dryncss on thc stcam
bath.
To dctcrminc whcthcr or not thc sodium cymcnc-sulfonate thus obtained was free
from thc othcr isomcr (thc sodium salt of cymcnc-2-sulfonic acid, CHs = l), a portion of
it was convcrtcd into thc sulfamidc, the lattcr subjected to a fractional crystallization
and thc mclting point of each fraction dctcrmincd. In cvcry casc the melting point of
thc sulfamide was found to bc 149 9" (corr.)which is the mclting point of thc sulfamidc
of cymcne-3-sulfonic acid (C€1~=1). Thcrc was no indication of the prcsencc of the
othcr isomer.
The matcrial was dricd a t 140"; yicld 7D'/'c.
Alkali Fusion of Sodium Cymene-sulfonate to Form Thymol.-The
fusion apparatus in which all of the following experiments were performed
consisted of a small iron pot, of about 3OOcc. capacity, provided with a
cover and stirring device. It was heated in a bath consisting of a eutectic
mixture of sodium and potassium nitrates. The whole apparatus was
TABLRI
YIELDS OF THYMOLOBTAINED BY 1'1113 PUSIONOX? SODIUM CYMENE-SULFONATE WITH
ALK.41,I UNDER rARIOUS CONDITIONS
*rclllp.
c.
320
200
270
350
3x3
350
350
330
350
3350
320
350
390
360
a Potassium hydroxidc uscd.
Tinic
Hours
1 1 2
1/2
'/?
'/z
3
1
'/ a
2
'/4
'/P
' 1 2
3
1 '
I 2
Yield
76
53 .7
44.7
14 .3
59 .O
51.2
47 .o
57.7
48.7
64.3
15.4
1 1 , l
0 . 5
43 8
'/2 .XI.1
Sodium hydroxidc uscd.
well insulated so that any desired temperature could be maintained con-
stant to within 2-3". The yield was determined by dissolving the cold
alkaline melt in water, acidifying it with dil. sulfuric acid and extracting the
solution with ether. The ether solution was dried over anhydrous sodium
sulfate, the ether removed by distillation and the residue fractionated.
5. June, 1923 PORMALDENYDE IN PABAPORMALDEHYDG 1493
The thymol fraction was collected in a weighed receiver and the weight of
thymol determined. The preceding table shows the results obtained.
It is to be noted from the table that potassium hydroxide is far superior
to sodium hydroxide with respect to the yield of thymol. The best yield
was obtained using 3 parts of potassium hydroxide to 1part of sulfonate a t
350' with a fusion period of l,/Z hour, However, considering the experi-
mental error, practically the same yield was obtained using only 2 parts of
potassium hydroxide. By using mixtures of the two hydroxides better
yields were obtained than with sodium hydroxide alone, the yield increasing
with the proportion of potassium hydroxide in the mixture.
The synthetic thymol obtained when seeded with a small crystal of
natural thymol solidified completely. It was identified by its phenyl-
urethane derivative (m. p., 107") and its formation of trinitrothymol (m.
Summary
p., 109").
An improved method is described for the synthesis of thymol from p-
cymene. The yields obtained in the various steps of the process indicate
the possibility of utilizing p-cymene, the main constituent of so-called
sulfite turpentine, as a source for synthetic thymol.
WASHINGTON,D. C.
[CONTRIBUTION FROX THE RESEARCHLABORATORY OR APPLIED CHEMISTRY,
MASSACHUSETTSINSTITUTEOF TECHXO+OGY,No. 331
THE DETERMINATION OF FORMALDEHYDE IN
PARAFORMALDEHYDE1
BYP. BORGSTROMAND W. G. HORSCH
Received December 9, 1922
The object of this paper is to present the results of a study of certain
methods for the determination of formaldehyde in paraformaldehyde.
Of the many methods available2for the determination of formaldehyde the
following will be considered: (1) fixed alkali, (2) iodimetric, (3) peroxide,
(4) neutral sulfite, (5) oxidation with permanganate or dichromate in an
acid solution and weighingthe carbon dioxideproduced.
Delepine3 gives the formula of paraformaldehyde as (CHzO)iz.HzO
showingwater as the only impurity. To obtain a standard of composition,
a sample of paraformaldehyde was analyzed in the Liebig combustion
furnace. In two determinations the carbon dioxide absorbed gave by cal-
culation 96.80 and 96.73 (mean, 96.77%). The water absorbed was very
close to 3.23%.
This work was financed by the National Electrolytic Company and is published
with their kind permission.
Lockeman and Corner, Z, anal. Chem., 54, 11 (1915).
a Delepine, Bull. sac, chim., [3]17, 849 (1897).