Synthesis of 1‐(N‐arylaminomethyl)‐3‐methyl‐1,8‐dihydrocycloheptapyrazol‐8‐ones

Abstract

Reactions of 3‐methyl‐1,8‐dihydrocycloheptapyrazol‐8‐one (2) with arylamines in the presence of formaldehyde gave 1‐(N‐arylaminomethyl)‐3‐methyl‐1,8‐dihydrocycloheptapyrazol‐8‐ones 5a‐l in good yields. 1,3,5‐Tris(phenyl‐ and 4‐methoxyphenyl)hexahydro‐1,3,5‐triazines or bis(3‐nitroanilino)methane, which were condensation products of arylamines and formaldehyde, also reacted with compound 2 to afford 5a,c,j, respectively.