Synthesis of vicinal aminoiodo- and (acetylamino)iodo-l-alkylpyrazoles
摘要:
3- and 5-(Acetylamino)-4-iodo-1-alkylpyrazoles were obtained by successive acylation and iodination from 3- and 5-amino-1-alkylpyrazoles without isolating intermediate (acetylamino)pyrazoles. 3- and 5-Iodo- and 3,5-diiodo-4-amino-1-methylpyrazoles were synthesized from appropriate iodonitropyrazoles by reduction with SnCl2 in HCl.
4-Iodo-1-methylpyrazoles react with a nitrating mixture at 55 degrees C to give the corresponding 4-nitro-1-methylpyrazoles. The qualitative dependence of the nitrodeiodination rate on the structure of the heterocycles and the reaction conditions was considered.