Phosphorus Oxychloride in Organic Synthesis. Part 3: Synthesis of α-Benzoylaminocinnamic Acids

A new approach to the activation of reactants during the condensation of aromatic aldehydes with N-aroylglycines (acting as CH-acids) is described. The condensation reaction carried out on heating in phosphorus oxychloride leads to a high yield of 4-benzylideneoxazol-5-one derivatives. The hydrolysis of these intermediate products yields the target α-benzoylaminocinnamic acids. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 7, pp. 41 – 42, July, 2005.