Complementary synthetic approaches to enantiomerically pure C3 alkylated or arylated NH free or N-substituted isoindolinones have been developed. The key step is elaboration of diversely substituted 2-alkyl- and arylbenzylamines, which can be submitted to a bis-metallation process followed by interception with a carbonylating agent. They can be also converted into N-alkylbromobenzyl-carbamates or into bromobenzyldicarbamates and the assembly of the titled compounds can be readily ensured by reliance upon the Parham cyclization process. (c) 2007 Elsevier Ltd. All rights reserved.
Organoselenium-catalyzed enantioselective syn-dichlorination of unbiased alkenes
作者:Bradley B. Gilbert、Stanley T.-C. Eey、Pavel Ryabchuk、Olivia Garry、Scott E. Denmark
DOI:10.1016/j.tet.2019.05.054
日期:2019.8
the enantioselective suprafacial dichlorination of alkenes catalyzed by electrophilic organoselenium reagents has been developed to address these limitations. The evaluation of twenty-three diselenides as precatalysts for enantioselective dichlorination is described, with a maximum e.r. of 76:24 Additionally, mechanistic studies suggest an unexpected DynamicKineticAsymmetricTransformation (DyKAT)
烯烃的对映选择性二氯化是有机合成中持续存在的挑战,因为亲电子氯和亲核氯化物选择性和独立地反面递送至烯烃的局限性。开发用于分离烯烃的对映选择性二氯化的通用方法将允许获得多种多卤代天然产物。因此,已经开发了由亲电子有机硒试剂催化的烯烃的对映选择性表面二氯化来解决这些限制。描述了对 23 种二硒化物作为对映选择性二氯化反应预催化剂的评估,最大 er 为 76:24 此外,机理研究表明意外的动态动力学不对称转化 (DyKAT) 过程可能是有效的。