PROCESS FOR THE PREPARATION OF 3-PHENYLPROPIONIC ACID

摘要

Process for the preparation of 3-phenylpropionic acid in which 3-phenylpropanal is subjected to an oxidation, at elevated temperature, in particular at a temperature of between 40 and 80 DEG C, using a medium containing molecular oxygen. A high degree of conversion and a high selectivity are obtained. The starting material 3-phenylpropanal can be prepared in a suitable manner through the hydrogenation of cinnamaldehyde in the presence of a Pd-containing catalyst, after which the reaction mixture obtained can without intermediate further processing be used in the oxidation reaction. The combination of the two process steps constitutes a simple, commercially attractive process for the preparation of 3-phenylpropionic acid using cinnamaldehyde as a starting material. 3-phenylpropionic acid can be used in particular in the preparation of pharmaceuticals such as HIV protease inhibitors.