Silver Acetate/TF-BiphamPhos-Catalyzed endo-Selective Enantioselective 1,3-Dipolar Cycloaddition of Azomethine Ylides with Vinyl Phenyl Sulfone
作者:Gang Liang、Min-Chao Tong、Chun-Jiang Wang
DOI:10.1002/adsc.200900552
日期:2009.12
The first catalytic endo-selective 1,3-dipolarcycloaddition of azomethine ylides and vinyl phenyl sulfone has been developed successfully. The highly efficient silver acetate (AgOAc)/TF-BiphamPhos catalytic system exhibited high reactivity, excellent diastereoselectivity (>98:2), good enantioselectivity (67–92% ee) and broad substrate scope under mild conditions.
Asymmetric synthesis of aryl‐substituted pyrrolidines by using CFAM ligand–AgOAc chiral system via 1,3‐dipolar cycloaddition reaction
作者:Nurzhan Beksultanova、Özdemir Doğan
DOI:10.1002/chir.23557
日期:——
reactions for the synthesis of chiralpyrrolidines. These chiral ligands were used with AgOAc in 1,3-DC reactions taking place between the aryl-substituted azomethine ylides and N-methylmaleimide as the dipolarophile. In each case, the expected aryl-substituted pyrrolidines were obtained in good to excellent yields with acceptable enantioselectivities favoring only the endo product. The chiral catalyst system
我们制备了基于二茂铁基氮丙啶基甲醇核心单元(简称FAM)的配体库,该核心单元具有苯基、环己基和萘基,可用于 1,3-偶极环加成 (1,3-DC) 反应用于合成手性吡咯烷。这些手性配体与 AgOAc 一起用于芳基取代的偶氮甲碱叶立德和作为亲偶极试剂的N-甲基马来酰亚胺之间发生的 1,3-DC 反应。在每种情况下,都以良好至优异的收率获得了预期的芳基取代的吡咯烷,并且具有可接受的对映选择性,仅有利于内产物。手性催化剂体系CFAM4 –AgOAc 也用于与不同亲偶极试剂(如马来酸二甲酯、丙烯酸叔丁酯、丙烯酸甲酯、反式查耳酮、乙烯基砜。在每种情况下,尽管 ee 较低,但都以可接受的收率获得了环加合物。幸运的是,结晶时可以将 ee 提高至 >99%。