Alkylphosphonous acid diesters, novel reagents for the oxalimide cyclization to penems
作者:K.-H. Budt、G. Fischer、R. Hörlein、R. Kirrstetter、R. Lattrell
DOI:10.1016/s0040-4039(00)79085-x
日期:1992.9
Alkylphosphonous acid diesters MeP(OR)23a-b were shown to be highly effctive and mild reducing reagents in the oxalimide cyclization of azetidinone-1-oxalyl-4-di- or tri-thiocarbonates or 4-thioesters1a-t forming penems 2a-t at lower temperature shorter reaction times, and higher yields compared to classical phosphites P(OMe)3 and P(OEt)3.
烷基亚膦酸二酯MeP(OR)2 3a-b在氮杂环丁酮-1-草酰-4-二-或三硫代碳酸酯或4-硫酯1a-t生成青霉烯2a-t的草酰亚胺环化反应中显示出高效率和温和的还原剂与传统的亚磷酸酯P(OMe)3和P(OEt)3相比,在较低的温度下t的反应时间更短,产率更高。