Facile synthesis of α-aminophosphine oxides from diarylphosphine oxides, arynes and formamides
Wen-Bin Huang1, Li-Qi Qiu1, Fang-Yu Ren1
1State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, P. R. China. heln@nankai.edu.cn.
Abstract:
The straightforward synthesis of α-amino phosphine oxides via three-component reactions involving arynes, formamides and diarylphosphine oxides is disclosed. This method employs the aryne to activate formamide, without an external activating reagent, which is operationally simple under mild conditions with high efficiency. Furthermore, mechanistic perception suggests a cascade sequence including formal [2 + 2] cycloaddition of the aryne with a CO bond, and a 1,4-addition of the H-P(O) compounds to the enamine intermediates.
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