GB617191A - Preparation of substituted benzoic acid esters and salts thereof - Google Patents

Abstract

3 - (21 - Methylpiperidino) - propyl - p - butoxy - benzoate <FORM:0617191/IV(b)/1> and its acid addition salts are prepared by esterification, e.g. by the reaction, preferably in an inert solvent, of a p-n-butoxy benzoyl halide with 3 - (21 - methylpiperidino) - propyl alcohol or by the reaction of p-n-butoxybenzoic acid with a 3-(21-methylpiperidino)-propyl halide in a solvent such as isopropyl alcohol, giving in each case the hydrohalide salt which is convertible to the free base on treatment with alkali. Other salts of the ester may be prepared by treating it with the appropriate acid or by an exchange reaction between a salt of the ester and the appropriate acid. The compounds are used as an sthetics. In examples: (1) p-n-butoxybenzoic acid is treated with 3-(21-methylpiperidino)-propyl chloride in isopropanol to give 3-(21-methylpiperidino)-propyl-p-n-butoxybenzoate hydrochloride; (2) the product of (1) is treated with aqueous sodium hydroxide to give the free ester; (3) 3 - (21 - methylpiperidino) - propyl alcohol is treated with p-n-butoxybenzoyl chloride in benzene to give the product of (1). The Specification as open to inspection under Sect. 91 comprises also the preparation of the products by trans-esterification, condensation and replacement. This subject-matter does not appear in the Specification as accepted.