METHOD FOR PRODUCING 1-(1-TERT-BUTOXYCARBONYL-4-PIPERIDYLACETYL)-4-MESYLOXYPIPERIDINE AND 1-(1-TERT-BUTOXYCARBONYL-4-PIPERIDYLACETYL)-4-MESYLOXYPIPERIDINE

摘要

The object of the present invention is to provide 1-(1-tert- butoxycarbonyl-4-piperidylacetyl)-4- mesyloxypiperidine having a low content of impuritiesThe object can be solved by a method for preparing 1-(1-benzyl-4-piperidylacetyl)-4-hydroxypiperidine, comprising the steps of:(1) reductively reacting 1-benzyl-4-piperidylidene acetic acid ethyl ester represented by the formula [1]:to obtain 1-benzyl-4-piperidyl acetic acid ethyl ester represented by the formula [2]: (2) adding an ammonium chloride aqueous solution and an organic solvent to the liquid containing 1-benzyl-4-piperidyl acetic acid ethyl ester, mixing the whole, and separating into an organic layer and an aqueous layer, (3) collecting 1-benzyl-4-piperidyl acetic acid ethyl ester from the organic layer, and (4) reacting the obtained 1-benzyl-4-piperidyl acetic acid ethyl ester with 4-hydroxypiperidine represented by the formula [3]:in the presence of base, to obtain 1-(1-benzyl-4-piperidylacetyl)-4-hydroxypiperidine represented by the formula [4]: