Patent ID: 6884893
Filing Date: 2005-04-26
Classification: C07D

Abstract:
1. A process for the selective cleavage of a cycloanhydride of the formula I in which A is benzyl, alkyl having from 1 to 6 carbon atoms or aryl, to give a corresponding monoester, comprising reacting the compound of the formula I a) with a chiral aminoalcohol of the general formula II  in which X R, R R in an inert solvent, or b) with a chiral aminoalcohol of the general formula III  in which X R′, R R in toluene, benzene or xylene at a temperature of from 15° to 35° C., in high selectivity to give a diastereomer, and optionally subsequently reducing the monoester using boron hydride, and then closing the ring to give the corresponding lactone.