Department of Chemistry, Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Tianjin University, and Collaborative Innovation Centre of Chemical Science and Engineering (Tianjin), Tianjin 300072, P. R. China.
Chem Soc Rev. 2019 Sep 16;48(18):4921-4942. doi: 10.1039/c9cs00086k.
The construction of carbon-carbon bonds is a central tenet of modern synthetic chemistry. Metal-catalyzed C-H functionalization can serve as a particularly powerful tool for achieving carbon-carbon bond formation. This review summarizes the early adventures and recent advancements in catalytic transformation of unactivated C(sp3)-H bonds into C(sp3)-C(sp3) bonds. To date, three main strategies have emerged to enable this transformation, namely, metallocarbene-triggered C(sp3)-H alkylation, auxiliary-directed C(sp3)-H alkylation, and photo-induced C(sp3)-H alkylation. Compared with traditional cross-coupling reactions having both coupling partners activated with functional groups or base-promoted enolate chemistry, catalytic alkylation of unactivated C(sp3)-H bonds for C(sp3)-C(sp3) bond formation not only offers novel disconnections in retrosynthetic analysis, but also represents the future trend in green and atom-economic chemistry.
碳-碳键的构建是现代合成化学的一个基本原则。金属催化的 C-H 官能化可以作为形成碳-碳键的一种特别强大的工具。本文综述了未活化 C(sp3)-H 键转化为 C(sp3)-C(sp3)键的催化转化的早期探索和最新进展。迄今为止，已经出现了三种主要策略来实现这种转化，即金属卡宾引发的 C(sp3)-H 烷基化、辅助导向的 C(sp3)-H 烷基化和光诱导的 C(sp3)-H 烷基化。与传统的交叉偶联反应相比，具有两个偶联伙伴用官能团或碱促进烯醇化物化学活化相比，未活化 C(sp3)-H 键的催化烷基化用于 C(sp3)-C(sp3)键形成不仅在逆合成分析中提供了新的切断，而且代表了绿色和原子经济性化学的未来趋势。
