GB773748A - Method of preparing quaternary salts of amino carbinols - Google Patents

Abstract

A method of preparing an hydroxy quaternary ammonium salt represented by the formula: <FORM:0773748/IV(b)/1> wherein R1, R2 and R3 are lower alkyl groups having from 1 to 3 carbon atoms or R1 and R2 together form a pyrrolidino or piperidino ring and X is the anion of a hydrocarbyl sulphonic acid or a halogenohydrocarbyl sulphonic acid comprises condensing a phenyl cyclohexyl ketone with an ester of a monohalogenacetic acid to give a hydroxy ester: <FORM:0773748/IV(b)/2> reducing this ester to a glycol: <FORM:0773748/IV(b)/3> reacting the glycol with a hydrocarbyl sulphonic acid halide or a halogenohydrocarbyl sulphonic acid halide at a temperature not exceeding 50 DEG C. and the resulting ester with a tertiary amine NR1R2R3. The reduction of the hydroxyester to the glycol is preferably effected with lithium aluminium hydride. Sodium borohydride and catalytic reduction are also suitable. Sulphonyl halides which may be reacted with the glycol include p-toluene, p-bromobenzene and methane sulphonyl chlorides. In examples: (1) phenyl cyclohexyl ketone and ethyl bromoacetate are reacted in the presence of zinc to form ethyl b -phenyl, b -cyclohexyl-, b -hydroxy propionate which is reduced with lithium aluminium hydride to 1-phenyl-1-cyclohexyl-1,3-propanediol. Reaction of this with p-toluenesulphonyl chloride gives 1-phenyl-1-cyclohexyl-1 - hydroxypropyl - 3 - p - toluenesulphonate which is reacted with N-methyl-pyrrolidine to form N - (3 - phenyl - 3 - cyclohexyl - 3 - hydroxypropyl) - N - methyl pyrrolidinium - p-toluenesulphonate; (2) 1 - phenyl - 1 - cyclohexyl - 1 - hydroxy - propyl - 3 - p - toluenesulphonate and triethylamine are heated in ethanol containing a little phenol to form N-(3 - phenyl - 3 - cyclohexyl - 3 - hydroxypropyl)-triethylammonium p-toluenesulphonate.