N-alkylation andN-arylation of anilines starting from a mild N?Mg reagent: Its activation causing the ?N?C? coupling to extend the unified structure-reactivity relationship
作者:Koji Matsuo、Yoshiaki Shichida、Hiroshi Nishida、Satsuki Nakata、Masao Okubo
DOI:10.1002/poc.610070103
日期:1994.1
New N-alkylation and N-arylation procedures starting from anilinomagnesium (ArNHMgBr) are reported. For N-alkylation with alkyl bromides, addition of hexamethylphosphoramide to an ArNHMgBr solution in tetrahydrofuran (THF) is effective. After heating at 55°C, N-monoalkylation product was obtained in 60–90% yield, slight dialkylation taking place. The combined use of aryliminodimagnesium [ArN(MgBr)2]
据报道,从苯胺镁(ArNHMgBr)开始新的N-烷基化和N-芳基化程序。为了用烷基溴进行N-烷基化,向在四氢呋喃(THF)中的ArNHMgBr溶液中添加六甲基磷酰胺是有效的。在55°C加热后,以60-90%的收率获得N-单烷基化产物,发生少量的二烷基化反应。芳基二镁[ArN(MgBr)2 ]与α,ω-二溴代烷烃的组合使用可产生N-芳基氮杂环烷烃。对于N用碘代苯进行芳基化,用吡啶代替THF以及另外使用碘化亚铜(I)都是有效的。用碘代苯在115°C加热后,获得一元和二芳基化产物,其中前者占主导地位。ArNHMgBr和N,N,N ',N'-四甲基乙二胺作为铜物种的配体的组合使用可有效消除二芳基化和其他不希望的产物,并以极好的收率得到二芳基胺。该方法优于常规的Ullmann和Chapman方法。极性溶剂和铜盐是有效的添加剂,可将ArNHMgBr或ArN(MgBr)2与烷基和芳基卤化物“惰性结合”成