Reduction of alkyl esters of carbonic-carboxylic anhydrides to alcohols

Abstract

There is disclosed the reduction of alkyl esters of carbonic-carboxylic acid anhydrides at elevated temperature and pressure in the presence of platinum group metal catalysts, especially palladium on activated carbon, to make alcohols. Novel alkyl esters of carbonic-carboxylic acid anhydrides are disclosed, and can be used to make the corresponding alcohols, e.g., substituted benzyl alcohols. The alcohols can be converted to the corresponding halo, e.g., chloro, compounds. The substituted benzyl halides can be reacted with di(lower alkoxy)propionitriles, and the resulting 5-benzyl pyrimidines such as trimethoprim, 2,4-diamino-5-(3,4,5-trimethoxybenzyl)-pyrimidine, which is a known anti-bacterial agent, are especially useful in combination with sulfa drugs such as sulfamethoxazole. Other alcohols that can be made in accordance with the invention include 2,6-pyridine dimethanol which can be used to make pyridinol carbamate, an anti-inflammatory agent and an anti-arteriosclerotic agent and 1-aceto-4-hydroxymethyl-5-methyl imidazole, which can be converted into cimetidine.