Mechanism of Acylative Oxidation–Reduction–Condensation Reactions Using Benzoisothiazolones as Oxidant and Triethylphosphite as Stoichiometric Reductant
作者:Pavankumar Gangireddy、Vidyavathi Patro、Leighann Lam、Mariko Morimoto、Lanny S. Liebeskind
DOI:10.1021/acs.joc.7b00020
日期:2017.4.7
We previously described a new organocatalytic oxidation–reduction–condensation for amide/peptide construction. The reaction system relies on triethylphosphite as the stoichiometric reductant and organocatalytic benzoisothiazolone/O2 in air as the oxidant. The reaction was assumed to generate catalytic quantities of S-acylthiosalicylamides as electrophiles, which are rapidly intercepted by amine reactants
先前我们描述了一种用于酰胺/肽构建的新的有机催化氧化-还原-缩合反应。该反应系统依赖于亚磷酸三乙酯作为化学计量的还原剂和空气中的有机催化苯并异噻唑酮/ O 2作为氧化剂。假定该反应产生催化量的S-酰基硫代水杨酰胺作为亲电试剂,其被胺反应物迅速拦截以生成酰胺/肽和邻-巯基苯甲酰胺。然后在铜催化的需氧条件下将后者缓慢重氧化为苯并异噻唑酮,以完成催化循环。为了获得机理上的理解,我们在此描述对S的化学计量生成的研究-亚磷酸三乙酯作为末端还原剂,在各种氧化-还原-缩合条件下,由各种苯并异噻唑酮和羧酸生成-酰基硫基水杨酰胺。这些研究表明,当苯并异噻唑酮与亚磷酸三乙酯反应时(包括某些类别的苯并异噻唑酮被亚磷酸三乙酯快速直接脱氧),存在多种反应途径,并可以确定最佳的反应特征(苯并异噻唑酮的结构和溶剂)来生成硫酯。这些探索将为我们开发基于苯并异噻唑酮和相关基序的高效,稳健的有机催化氧化-还原-缩合反应做出的努力。
Benzyl and t-butyl sulfoxides as sulfenyl halide equivalents: a convenient preparation of benzisothiazolones
作者:Stephen W. Wright、Matthew M. Abelman、Lori L. Bostrom、Ronald L. Corbett
DOI:10.1016/0040-4039(92)88037-6
日期:1992.1
A new methodology is described for the synthesis of benzisothiazolones from benzylsulfinyl or t-buthylsulfinyl substituted carboxamides that provides a mild alternative to conventional cyclization methods that employ halogens.