Reference

An improved process for the preparation of (-)-N-benzoyl-(2R,3S)-3-phenylisoserine

An improved process for the preparation of (-)-N-benzoyl-(2R,3S)-3-phenylisoserine. Chattopadhyay, Sunil Kumar; Sharma, Ram Prakash; Kumar, Sushil ( Council Scientific Industrial Resesarch, India). Indian IN 186132 A 23 Jun 2001, 18 pp. (English). (India). CODEN: INXXAP. CLASS: ICM: C07C101-08. APPLICATION: IN 1997-DE1718 24 Jun 1997. DOCUMENT TYPE: Patent CA Section: 34 (Amino Acids, Peptides, and Proteins) An improved process for the prepn.Several substances with their cas registry numbers 32981-85-4 and 117486-25-6 may be metioned in this study. of (-)-N-benzoyl-(2R,3S)-3-phenylisoserine starts with dihydroxylation of trans-Me cinnamate in a polar solvent with a mixt. of hydroquinine 1,4-phthalazinediol diether, potassium ferricyanide, potassium carbonate and potassium osmate dihydrate (AD-mix a) at room temp. for 12-24 h. Subsequent steps involve treating the diol with thionyl chloride in presence of an org. base in a chlorinated solvent at 0-25°C and then with magnesium or ammonium bromide for 7-8 h, treating the resulting bromohydrin with a metal azide at 60-70°C for 40-45 h, reacting with benzoyl chloride in a chlorinated org. solvent in presence of a base, catalytic hydrogenation, and hydrolysis. .