Scalable and Chemoselective Synthesis of γ-Keto Esters and Acids via Pd-Catalyzed Carbonylation of Cyclic β-Chloro Enones
作者:Justin M. Kaplan、Damian P. Hruszkewycz、Iulia I. Strambeanu、Christopher J. Nunn、Kelsey F. VanGelder、Anna L. Dunn、Derek I. Wozniak、Graham E. Dobereiner、David C. Leitch
DOI:10.1021/acs.organomet.8b00468
日期:2019.1.14
The Pd-catalyzed carbonylation of cyclic β-chloro enones using simple phosphine ligands is described. Screening identified P(Me)(t-Bu)2 as the most general ligand for an array of chloro enone electrophiles. The reaction scope has been evaluated on a milligram scale across 80 examples, with excellent reactivity observed in nearly every case. Carbonylation can be achieved even in the presence of potentially
描述了使用简单的膦配体的Pd催化的环状β-氯烯酮的羰基化反应。筛选确定P(Me)(t -Bu)2是一系列氯烯酮亲电子试剂的最一般配体。已在80个实例中以毫克为单位对反应范围进行了评估,几乎在每种情况下都观察到了出色的反应性。即使在潜在的敏感或抑制性官能团(包括碱性氮以及芳基氯化物或溴化物)的存在下,也可以实现羰基化。已经以克为单位运行了20个示例,证明了可伸缩性和实用性。使用P(Me)(t -Bu)2反应速率取决于亲核试剂和亲电试剂的同一性,在一组标准条件下,完成时间在3至> 18 h之间变化。切换到P(吨-Bu)3为吨他羰基化3- chlorocyclohex -2-烯酮在一剧烈的速率增加的甲醇的结果,使得能够与动力学与限速质量传递一致的有效的催化。3-氯环己-2-烯酮和3-氧代环己-1-烯羰基氯的化学计量氧化加成到Pd [P(t -Bu)3 ] 2和Pd(PCy 3)2上能够表征和分离几种潜在的催化中间体,包括由P(t