Palladium Catalyzed Monoselective α-Arylation of Sulfones and Sulfonamides with 2,2,6,6-Tetramethylpiperidine·ZnCl·LiCl Base and Aryl Bromides
作者:Thomas Knauber、Joseph Tucker
DOI:10.1021/acs.joc.6b01062
日期:2016.7.1
Negishi-type α-arylation of sulfones and sulfonamides with a broad range of aryl bromides has been developed. The substrates are selectively metalated in situ with tmp·ZnCl·LiCl base (tmp: 2,2,6,6-tetramethylpiperidine) and cross-coupled in the presence of a catalyst system that is generated from Pd(dba)2 and XPhos. Electron-deficient, electron-rich, and heterocyclic aryl bromides have been successfully
已经开发了钯和广泛范围的芳基溴化物催化的砜和磺酰胺的Negishi型α-芳基化反应。使用tmp·ZnCl·LiCl碱(tmp:2,2,6,6-四甲基哌啶)将基体选择性地金属化,并在由Pd(dba)2生成的催化剂体系存在下交叉偶联和XPhos。缺电子,富电子和杂环芳基溴化物已成功交叉偶联,敏感的官能团具有良好的耐受性。简单的芳基溴化物在60°C的THF中转化过夜,而杂芳基溴化物则在微波反应器中在130°C的2小时内有效偶联。以良好的产率获得了所需的单芳基化的α-支化的苄基砜和磺酰胺,并且未检测到过芳基化。该程序是并行药物化学中后期功能化的理想选择。