A Direct and Mild Conversion of Tertiary Aryl Amides to Methyl Esters Using Trimethyloxonium Tetrafluoroborate: A Very Useful Complement to Directed Metalation Reactions
作者:Gary E Keck、Mark D McLaws、Travis T Wager
DOI:10.1016/s0040-4020(00)00969-8
日期:2000.12
of tertiary amides directly to methyl esters has been investigated. The process involves a two-step, one pot procedure in which a tertiary amide is first treated with trimethyloxonium tetrafluoroborate to generate an imidate intermediate which is then hydrolyzed, generally by the addition of saturated aqueous sodium bicarbonate solution. Although this process fails for aliphatic amides, very good yields
已经研究了将叔酰胺直接转化为甲酯的直接方法的范围和一般性。该方法包括两步一锅法,其中首先用四氟硼酸三甲基氧鎓处理叔酰胺以生成亚氨酸酯中间体,然后通常通过加入饱和的碳酸氢钠水溶液将其水解。尽管该方法对于脂肪族酰胺是失败的,但是对于衍生自芳族羧酸的各种酰胺都实现了非常好的收率。在N-烷基上的立体位阻是很好的耐受性。因此,N,N-二甲基,-二乙基和-二异丙基酰胺均可被成功利用。