[EN] A PROCESS FOR THE PREPARATION OF ANTI-PSCHOTIC 3-[2-[4-(6-fluoro-1,2-benzisoxazol-3-yl)-1-piperidinyl]ethyl]-6,7,8,9-tetrahydro-2-methyl-4H-pyrido[1,2,-a]pyrimidin-4-one<br/>[FR] PROCEDE DE PREPARATION DE 3-[2-[4-(6-FLUORO-1,2-BENZISOXAZOL-3-YL)-1-PIPERIDINYL]ETHYL]-6,7,8,9-TETRAHYDRO-2-METHYL-4H-PYRIDO[1,2,-A]PYRIMIDIN-4-ONE ANTIPSYCHOTIQUE
申请人:RPG LIFE SCIENCES LTD
公开号:WO2001085731A1
公开(公告)日:2001-11-15
A process for the preparation of 3-substituted ethyl-6,7,8,9-tetrahydro-2-methyl-4H-pyrido[1,2,-a]pyrimidin-4-one of formula (IIB) where X may be halo, acyloxy, or sulfonyloxy such as tosyloxy or mesyloxy, an intermediate in the synthesis of the anti-psychotic risperidone. The process comprises hydrogenation of 3-substituted ethyl-2-methyl-4H-pyrido[1,2,-a]pyrimidin-4-one in aqueous inorganic acid medium at atmospheric to 60 psi at 0-100 °C in the presence of a metal catalyst and the product is isolated. A process for the preparation of risperidone of formula (I) comprising condensation of 3-substituted ethyl-6,7,8,9-tetrahydro-2-methyl-4H-pyrido[1,2,-a]pyrimidin-4-one with 6 fluoro-3-(4-piperidinyl)-1, 2-benzosoxazolein water in the presence of an inorganic base at 25 - 100 °C and the product is isolated.