Acid Catalyzed Alcoholysis of Sulfinamides: Unusual Stereochemistry, Kinetics and a Question of Mechanism Involving Sulfurane Intermediates and Their Pseudorotation
formed in this reaction with a full or predominant inversion of configuration at chiral sulfur or with predominant retention of configuration. The steric course of the reaction depends mainly on the size of the dialkylamido group in the sulfinamides and of the alcohols used as nucleophilic reagents. It has been found that bulky reaction components preferentially form sulfinates with retention of configuration
Asymmetric Synthesis of 2<i>H</i>-Azirine 2-Carboxylate Esters
作者:Franklin A. Davis、Hu Liu、Chang-Hsing Liang、G. Venkat Reddy、Yulian Zhang、Tianan Fang、Donald D. Titus
DOI:10.1021/jo991389f
日期:1999.11.1
sulfenic acid (RSOH) from nonracemic N-sulfinylaziridine 2-carboxylate esters (4). Optimum yields were obtained when the aziridine was treated with TMSCl at -95 degrees C followed by LDA, which was attributed to the improved leaving group ability of an silicon-oxonium species. By using this new methodology the first asymmetric syntheses of the marine cytotoxic antibiotics (R)-(-)- and (S)-(+)-dysidazirine