PRODUCTION OF N-ACETYLCYCLOHEXYLGLYCINE COMPOUND

摘要

PROBLEM TO BE SOLVED: To produce an N-acetylcyclohexylglycine compound useful as an intermediate for various pharmaceuticals and agrochemicals in high selectivity and yield by the nucleus hydrogenation of N-acetylphenylglycine. SOLUTION: The objective N-acetylcyclohexylglycine compound of formula II can be produced by the nucleus hydrogenation reaction of an N- acetylphenylglycine compound of formula I (R1 is H or an amino-protecting group; R2 is H or a carboxyl-protecting group) in the presence of a rhodium catalyst (preferably rhodium supported on a carbon carrier consisting of activated carbon or graphite). The reaction is preferably carried out by using an alcohol or water containing >=1 equivalent of a base as a reaction solvent. For example, 1.2 g of N-acetylphenylglycine and 240 mg of 5% rhodium/activated carbon catalyst are dissolved in 15 mL of a methanol solution, the obtained solution is stirred at 100 deg.C for 3 hr under a hydrogen pressure of 50 kg/cm2 to complete the reaction, the reaction mixture is filtered and the product is purified to obtain 1.08 g of N-acetylcyclohexylglycine having a purity of 99%.