PRODUCTION OF AMINOMETHYLPYRIDINES HAVING HALOGEN ATOM AT ALPHA-POSITION

摘要

PURPOSE:To obtain aminopyridines having a halogen atom at alpha-position in high yield by subjecting cyanopyridines having a halogen atom at alpha-position to catalytic reduction in the presence of a Raney nickel catalyst having a specific property. CONSTITUTION:Cyanopyridines having a halogen atom at alpha position are subjected to catalytic reduction in the presence of a Raney nickel catalyst to provide the objective aminopyridines having halogen atom at alpha-position. In this process, a Raney nickel having <=1.0cm/sec sedimentation rate and <=1000 H2ml/gNi/hr hydrogenated phenol activity is used as the catalyst. A Raney nickel having <=600H2ml/gNi/hr hydrogenated phenol activity and <=0.8cm/sec, especially <=0.6cm/sec sedimentation rate is especially preferable as the catalyst. Al content in the Raney nickel catalyst is preferably 3-8wt.% based on Ni content. 2-Chloro-5-cyanopyridine is preferably used as cyanopyridines having halogen atom at alpha-position.