Patent ID: 7741508
Filing Date: 2010-06-22
Classification: C07C,Y02P

Abstract:
1. A single pot process for the preparation of substituted cinnamic esters with trans-selectivity of Formula I, excluding the toxic and hazardous cyanides as an oxidizing agent: wherein: each of X R is selected from the group consisting of an alkyl, an aryl, an arylalkyl and an cycloalkyl group having carbon chain from 1 to 20 with or without substitutions at the aromatic ring, the process comprising the steps of: a) reacting cinnamaldehydes or cinnamyl alcohols of Formula II, wherein: R′ is selected from CHO and CH each of X with an oxidizing agent, a catalyst, and an alcohol, optionally in the presence of an organic solvent, while stirring at room temperature, or refluxing, or under microwave irradiation or ultrasound for a period of time between about 1 minute and about 20 hours, to obtain substituted cinnamic esters of Formula I with trans-selectivity with a yield up to 98% in a single step; b) filtering the reaction mixture obtained in step (a) and collecting the filtrate; c) concentrating the filtrate obtained in step (b) or directly passing the same through a column of solid adsorbent selected from the group consisting of alumina and silica gel; and d) eluting the packed column of step (c) with solvents of different polarities, to obtain the substituted cinnamic esters of Formula I with trans-selectivity free from side products.