摘要:
2,4-Xylenol can be obtained in high yield and high purity from a crude 2,4-xylenol isomer mixture containing 2,5-xylenol by selectively reacting the 2,5-xylenol with an aldehyde in the presence of an aromatic sulfonic acid, thereby converting the 2,5-xylenol into a xylenol-aldehyde condensate and, subsequently, separating the 2,4-xylenol, e.g., by distillation.
摘要:
Novel 4,4-bis(4-hydroxyphenyl)cyclohexanecarboxylic acid derivatives. These compounds can be prepared by reacting a cyclohexanone-4-carboxylic acid with a phenol.
摘要:
A process for preparing 4,4'-biphenol comprising subjecting 4,4-bis(4-hydroxyphenyl)cyclohexanol to decomposition and dehydrogenation in the presence of a dehydrogenation catalyst.4,4-Bis(4-hydroxyphenyl)cyclohexanol is a novel compound which can be prepared by reacting 4-hydroxycyclohexanone with phenol.
摘要:
An S-alkyl thiocarbamate base lens resin is obtained by reacting one or more NCO-containing compounds, such as xylylene diisocyanate, hexamethylene diisocyanate and/or tetrachloroxylylene diisocyanate, with one or more SH-containing aliphatic compounds, for example, a di(2-mercaptoalkyl) ether.
摘要:
An improved process for preparing organic isocyanates is disclosed. An organic amine is reacted with phosgene to yield a reaction product, through which hydrogen chloride gas is passed in the presence of an inert organic solvent whereby the gas included in the reaction product is removed and the acid substances and hydrolyzable chlorine-containing substances included therein are minimized.
摘要:
A process for purifying crude p-aminophenol which contains 4,4'-diaminodiphenyl ether and other impurities, which process comprising adding an alkali metal compound to the crude p-aminophenol in an aqueous medium in an atmosphere of an inert gas and, if necessary, in the presence of a reducing agent to give an aqueous solution of an alkali metal salt of p-aminophenol, and contacting the aqueous solution with an inert organic solvent immiscible with water to permit 4,4'-diaminodiphenyl ether and other impurities to be separated by extraction in the solvent.
摘要:
In a process for reacting N,N'-dialkylethylenediamine with urea in an aprotic polar solvent to prepare 1,3-dialkyl-2-imidazolidinone, a process comprising progressing the reaction while continuously adding N,N'-dialkylethylnediamine and urea into the aprotic polar solvent. The process is a high-yield manufacturing process in industry capable of efficiently producing very high purity 1,3-dialkyl-2-imidazolidinone which contains less than 0.1% by weight of by-product 1,3-dialkyl-2-imidazolidinimine derived from the raw materials.
摘要:
A process for producing an alkoxy-substituted tri-phenylamine comprising reacting an alkoxy-substituted cyclohexanone with a diphenylamine or an aniline, while forming said cyclohexanone in the same system from an alkoxy-substituted phenol by using said phenol as a hydrogen acceptor, in the presence of a hydrogen transfer catalyst and a catalytic amount of the alkoxy-substituted cyclohexanone corresponding to the alkoxy-substituted phenol used for the reaction, or after converting partially the alkoxy-substituted phenol to a catalytic amount of the alkoxy-substituted cyclohexanone under a hydrogen pressure in the presence of a hydrogen transfer catalyst, wherein a surface-supported catalyst is used as the hydrogen transfer catalyst.
摘要:
A novel bis-urea compound, preparation process of the compound, and preparation process of 1,3-dialkyl-2-imidazolidinone are disclosed and the disclosure provides a novel preparation process of 1,3-dialkyl-2-imidazolidinone and simultaneously enables effective utilization of N,N',N"-trialkyldiethylentriamine which lacks a large amount use and is desired to develop new application.
摘要:
This invention is an industrially efficient and improved process for the preparation of aliphatic polyisocyanates by using esters as the solvent for converting aliphatic polyamines to isocyanates.