Despite remarkable recent advances in transition-metal-catalyzed C(sp³)−C cross-coupling reactions, there remain challenging bond formations. One class of such reactions include the formation of tertiary-C(sp³)−C bonds, presumably due to unfavorable steric interactions and competing isomerizations of tertiary alkyl metal intermediates. Reported herein is a Ni-catalyzed migratory 3,3-difluoroallylation of unactivated alkyl bromides at remote tertiary centers. This approach enables the facile construction of otherwise difficult to prepare all-carbon quaternary centers. Key to the success of this transformation is an unusual remote functionalization via chain walking to the most sterically hindered tertiary C(sp³) center of the substrate. Preliminary mechanistic and radical trapping studies with primary alkyl bromides suggest a unique mode of tertiary C-radical generation through chain-walking followed by Ni–C bond homolysis. This strategy is complementary to the existing coupling protocols with tert-alkyl organometallic or -alkyl halide reagents, and it enables the expedient formation of quaternary centers from easily available starting materials.

尽管最近在过渡金属催化的 C(sp ³ )-C 交叉偶联反应方面取得了显着进展，但仍存在具有挑战性的键形成。一类这样的反应包括叔-C(sp ³ )-C 键的形成，大概是由于不利的空间相互作用和叔烷基金属中间体的竞争异构化。本文报道了未活化的烷基溴在远程三级中心的 Ni 催化迁移 3,3-二氟烯丙基化。这种方法可以轻松构建原本难以制备的全碳四元中心。这种转化成功的关键是通过链行走到空间位阻最大的三级 C(sp ³) 基板的中心。用伯烷基溴化物进行的初步机理和自由基捕获研究表明，通过链游走和 Ni-C 键均裂产生叔 C-自由基的独特模式。该策略是对现有的使用叔烷基有机金属或烷基卤试剂的偶联方案的补充，它能够从容易获得的起始材料中方便地形成季铵盐中心。