Nucleophilic phosphine-catalyzed [3+2] cycloaddition of allenes with N-(thio)phosphoryl imines and acidic methanolysis of adducts N-(thio)phosphoryl 3-pyrrolines: a facile synthesis of free amine 3-pyrrolines
作者:Bo Zhang、Zhengrong He、Silong Xu、Guiping Wu、Zhengjie He
DOI:10.1016/j.tet.2008.07.075
日期:2008.9
In this report, the dipolarophile imines with easily removable activating group O,O-diethyl(thio)phosphoryl have been investigated in the nucleophilic phosphine-catalyzed [3+2] cycloaddition reaction of electron-deficient allenes. Under the catalysis of a tertiary phosphine, N-(thio)phosphorylimines readily undergo the [3+2] cycloaddition reaction with ethyl 2,3-butadienoate or ethyl 2,3-pentadienoate
在该报告中,已经在亲电子膦催化的缺电子异戊烯的[3 + 2]环加成反应中研究了具有易于除去的活化基团O,O-二乙基(硫代)磷酰基的偶极亲子亚胺。在叔膦的催化下,N-(硫代)磷酸亚胺与2,3-丁二烯酸乙酯或2,3-戊二烯酸乙酯容易进行[3 + 2]环加成反应,得到相应的N-(硫代)磷酰基3-吡咯啉,中等至高收率,具有良好的非对映选择性。已通过PN键的酸性甲醇分解成功地从加合物中去除了(硫代)磷酰基,从而使游离胺3-吡咯啉的收率达到了中等至良好的收率,而没有发生严重的芳构化。因此,由膦与亚胺的膦催化的[3 + 2]环加成反应建立了N-未取代的3-吡咯啉的简便合成方法。