Direct Preparation of Guanidine from Trichloroacetamide. A Potentially Important Method to (−)-Tetrodotoxin
作者:Noboru Yamamoto、Minoru Isobe
DOI:10.1246/cl.1994.2299
日期:1994.12
Trichloroacetamides obtained via Overman [3,3] sigmatropic rearrangement were converted into dibenzyl guanidines. The key step was conversion of carbodiimide intermediate into guanidine by scandium or ytterbium trifluoromethane-sulfonates. This method was applied to a synthesis of guanidinium ring of (−)-tetrodotoxin.
通过 Overman [3,3] sigmatropic 重排获得的三氯乙酰胺被转化为二苄基胍。关键步骤是通过三氟甲烷磺酸钪或镱将碳二亚胺中间体转化为胍。这种方法被应用于合成 (-)- 河豚毒素的胍环。