HCID 21428883, compound → HCID 21428930, compound

Participants

Reaction Steps

A mixture of 4.2 parts of 5-chloro-N-{2-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl}-2-methoxy-4-nitrobenzamide in 150 parts of acetic acid is hydrogenated at normal pressure and at room temperature with 1 part of Raney-nickel catalyst. After the calculated amount of hydrogen is taken up, the catalyst is filtered off and the filtrate is evaporated. Water is added to the residue and the whole is alkalized with a diluted sodium hydroxide solution. The precipitated product is filtered off and crystallized from methanol. The product is filtered off (the filtrate is set aside) and dried, yielding a first fraction of 0.8 parts of 4-amino-5-chloro-N-{2-[4-(2,3-dihydro-2-oxo-1H-benzimidazol-1-yl)-1-piperidinyl]ethyl}-2-methoxybenzamide; mp. 230.1° C.

Provenance & Evidence