Efficient Syntheses of ω-Chloro-, ω-Imido- and ω-Aminoalkyl-1,2,4-triazoles fromN-Acyl-formamidinium Salts orN-Acylformamides and Hydrazines
作者:Ute Bechstein、Andrea Rumler、Jürgen Liebscher
DOI:10.1002/ardp.19923250813
日期:——
are transformed to ω‐functionalized N‐acylformamidinium salts 4 or formamide 6a by HCI catalyzed addition of chloromethylene iminium salts, derived from formamides 2 and POCI3. Advantageously, β‐halo‐propionyl‐formamidinium salts 4 can also be obtained from acrylonitrile. Regiospecific and chemoselective cyclization of N‐acyl‐formamidinium salts 4 or formamide 6a to ω‐functionalized 5‐alkyl‐1,2,4‐triazoles
ω - 卤素和 ω - 酰胺基烷基氰化物 1 通过 HCl 催化的氯亚甲基亚胺盐的加成转化为 ω - 功能化的 N - 酰基甲脒盐 4 或甲酰胺 6a,该盐衍生自甲酰胺 2 和 POCl3。有利地,β-卤代-丙酰基-甲脒盐4也可以从丙烯腈获得。N-酰基-甲脒盐4或甲酰胺6a到ω-官能化的5-烷基-1,2,4-三唑9的区域特异性和化学选择性环化可以通过与肼5反应,通过中间体N-酰基-脒腙8或吖嗪7在许多情况下必须单独分离和环化。5-邻苯二甲酰亚胺烷基-1,2,4-三唑 9 裂解为 5-(氨基烷基)-1,2,4-三唑 10。