Patent GB-1095791-A (GB)
Title: Condensation reactions
IPC: C07C51/56
Filed: 1965-03-16
Abstract: Condensation products are formed with loss of water from, on the one hand, an organic compound which contains at least one organic functional group in which a hydroxy radical is bonded to a carbon atom and, on the other hand, an organic or inorganic compound which contains an active hydrogen atom, in the presence of an aminoacetylene compound of the formula YC ­ CN(R)2, wherein R is a monovalent hydrocarbon radical, Y is R, -N(R)2 or a hydrogen atom, and two R groups on the same nitrogen atom can together form a divalent alkylene group.  When both reaction components are carboxylic acid molecules the product may be a carboxylic anhydride. Similarly, a cyclic anhydride is formed when two carboxylic acid groups are present in the same molecule.  Thus a cyclic anhydride is formed from succinic acid; normal carboxylic acid anhydrides are formed from acetic, n-butyric, benzoic, para-chlorobenzoic, phenylacetic, methoxyacetic, stearic, oleic, methacrylic, N-carbobenzoxy - gamma - methyl - L - glutamic and N - carbobenzoxy - gamma - benzyl - glutamic acids, bis - carbobenzoxy - L - cystine and N-carbobenzoxyalanine; and mixed anhydrides are formed from mixtures of acetic and propionic acids.  When the two reaction components are carboxylic acids and amines respectively, the products of the condensation reaction are amides.  Thus ethylene diamine and acetic acid give as a product CH3CONHCH2CH2NH COCH3, and aniline and benzoic acid give benzanilide.  Where the carboxylic acid group and the amino group are both situated on the same molecule the product is a lactam. Thus gamma-amino-butyric acid yields butyrolactam. By reacting N-protected amino acids with carboxylic-protected amino acids peptides or polypeptides may be formed.  Thus dimethyl-L-aspartate reacts with N-carbobenzoxy-gamma-methyl-L-glutamate to give a compound of the formula <FORM:1095791/C2/1> dimethyl - L - aspartate reacts with bis-carbobenzoxy - L - cystine to give a compound of the formula <FORM:1095791/C2/2> N-carbobenzoxy-alanine reacts with dibenzyl glutamate to give a compound of the formula <FORM:1095791/C2/3> and N - carbobenzoxy - gamma - benzylglutamic acid reacts with dibenzyl glutamate to give a compound of the formula <FORM:1095791/C2/4> By reacting alcohols with hydrogen halides corresponding halides such as n-decyl chloride or bromide, C6H5CH2CH2F and F(CH2)6F are formed.  By reacting carboxylic acids with alcohols, sugars, oximes and amidoximes the corresponding esters or acyloxy derivatives are formed.  Thus malonic acid reacts with ethanol to give CH3CH2OCOCH2COOCH2CH3, acetic acid reacts with 1,3-propyleneglycol to give CH3COOCH2CH2CH2OCOCH3, acetic acid reacts with methoxyethanol to give CH3COO CH2CH2OCH3, benzoic acid reacts with nitropheno to give C6H5COOC6H4NO2, and n-butyric acid reacts with HON = CHCH2CH3 to give CH3CH2CH2COON = CHCH2CH3. When the carboxylic group and the hydroxy group are both situated on the same molecule the product is a lactone.  Thus gamma-hydroxy-butyric acid yields butyrolactone.  Esters may also be prepared from mercaptans and carboxylic acids.  Thus acetic acid reacts with propyl mercaptan to give propylthiolacetate. Other products may be prepared from alcohols and organic phophines.  Thus propanol reacts with diphenylphosphine to give propyldiphenylphosphine.  C6H5CH2CON(CH3)2 and tert. C4H9CH2CON (CH3)2 are formed as by-products during the preparation of anhydrides or organic halides.  Acetylenic starting materials of the formula C6H5C ­ CN(CH3)2, C6H5C ­ CN(CH2CH3)2, C6H5C ­ CN(CH3)(CH2CH3), tert. C4H9C ­ CN(CH3)2, HC ­ CN(CH3)2, tert. C4H9C ­ CN(CH3)2 and (iso. C4H9)2NC ­ CN(iso. C4H9)2 are prepared by reacting lithium salts of amines with appropriately substituted haloacetylenes.