Wu Xinxin, Zhu Chen
Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-Ai Road, Suzhou, Jiangsu 215123, China.
Chem Commun (Camb). 2019 Aug 13;55(66):9747-9756. doi: 10.1039/c9cc04785a.
Direct functionalization of inert C(sp3)-C(sp3) and C(sp3)-H bonds represents one of the most valuable synthetic tactics, yet large obstacles remain in terms of reactivity and selectivity. Alkoxy radicals enable C-C bond scission via β-C elimination and C(sp3)-H bond cleavage through a hydrogen atom transfer (HAT) process, thus providing an efficient method to address these problems. In view of atom- and step-economy, the direct use of abundant alcohols as alkoxy radical precursors in radical transformations is of high synthetic value. This feature article summarizes our recent achievements in (a) C(sp3)-C(sp3) bond cleavage via ring-opening of cycloalkanols and (b) site-specific C(sp3)-H functionalization of unprotected aliphatic alcohols, along with the reconstruction of various new chemical bonds, e.g. C-halogen, C-C, C-N, C-S, and C-Se bonds.
惰性C(sp3)-C(sp3)键和C(sp3)-H键的直接官能团化是最有价值的合成策略之一，但在反应活性和选择性方面仍存在巨大障碍。烷氧基自由基能够通过β-C消除实现C-C键断裂，并通过氢原子转移（HAT）过程实现C(sp3)-H键裂解，从而提供了一种解决这些问题的有效方法。鉴于原子经济性和步骤经济性，在自由基转化中直接使用丰富的醇类作为烷氧基自由基前体具有很高的合成价值。这篇专题文章总结了我们最近在以下方面取得的成果：（a）通过环烷醇的开环实现C(sp3)-C(sp3)键断裂，以及（b）未保护脂肪醇的位点特异性C(sp3)-H官能团化，同时还实现了各种新化学键的重建，例如C-卤素键、C-C键、C-N键、C-S键和C-Se键。
