PROCESS FOR PREPARING 4-HYDROXY-N-BENZYL-2-PIPERIDINONE WHICH IS INTERMEDIATE FOR PREPARING ATORVASTATIN USEFUL AS HYPERLIPIDEMIA TREATING AGENT WITH HIGH YIELD UNDER MILD CONDITION

摘要

PURPOSE: A process for preparing 4-hydroxy-N-benzyl-2-piperidinone is provided, thereby easily preparing 4-hydroxy-N-benzyl-2-piperidinone which is an intermediate for preparing atorvastatin useful as a hyperlipidemia treating agent with high yield under mild condition. CONSTITUTION: The process for preparing 4-hydroxy-N-benzyl-2-piperidinone represented by formula (2) comprises hydrogenating 2,4-dioxo-N-benzyl-piperidine of formula (3) in organic solvent in the presence of ruthenium catalyst at 100 deg. C and 30 to 100 atmosphere, wherein the organic solvent is selected from methanol, ethanol, isopropanol, t-butanol, methylene chloride, tetrahydrofuran, acetonitrile, t-butanol, dimethylformamide, diethylether, ethylacetate, acetone and chloroform; and the ruthenium catalyst is selected from Ru2Cl4(BINAP)2NEt3, Ru2Cl4(Tol-BINAP)2NEt3, Ru2Cl2(BINAP)2, Ru2Br2(MINAP)2, RuHCl(BINAP), Ru(BINAP)CO2(CH3)2 and Ru(Tol-BINAP)CO2(CH3)2 in which Tol is toluene, BINAP is 2,2'-bis(diphenylphosphino)-1,1'-binaphtyl.