Palladium-Catalyzed Cyclization Reactions of 2-Vinylthiiranes with Heterocumulenes. Regioselective and Enantioselective Formation of Thiazolidine, Oxathiolane, and Dithiolane Derivatives
作者:Chitchamai Larksarp、Odile Sellier、Howard Alper
DOI:10.1021/jo010037h
日期:2001.5.1
palladium-catalyzed ring-expansion reaction of 2-vinylthiiranes with heterocumulenes to form sulfur-containing five-membered-ring heterocycles is described. This regioselective reaction requires 5 mol % of Pd(2)(dba)(3).CHCl(3) and 10 mol % of bidendate phosphine ligand (dppp, BINAP), at 50-80 degrees C, in THF. The reaction of 2-vinylthiiranes with carbodiimides, isocyanates, and ketenimines affords 1,3-thiazolidine
描述了2-乙烯基噻喃与杂枯烯的第一次钯催化的扩环反应,以形成含硫的五元环杂环。该区域选择性反应在THF中在50-80摄氏度下需要5 mol%的Pd(2)(dba)(3).CHCl(3)和10 mol%的双膦膦配体(dppp,BINAP)。2-乙烯基噻喃与碳二亚胺,异氰酸酯和酮亚胺的反应可得到1,3-噻唑烷衍生物,而与二苯乙烯或异硫氰酸酯的反应可形成1,3-氧杂硫杂环戊烷或1,3-二硫杂环戊烷化合物,分离效果良好或极好。产量最高可达ee的78%。