Stereoselective Synthesis of Trisubstituted Vinylboronates from Ketone Enolates Triggered by 1,3‐Metalate Rearrangement of Lithium Enolates
作者:Yue Hu、Wei Sun、Tao Zhang、Nuo Xu、Jianeng Xu、Yu Lan、Chao Liu
DOI:10.1002/anie.201909235
日期:2019.10.28
unprecedented stereoselective synthesis of trisubstituted vinylboronates is reported to proceed by direct borylation of lithium ketone enolates under transition-metal-free conditions. The stereospecific C-O borylation of lithium enolates was triggered by a carbonyl-induced 1,3-metalate rearrangement via a C-bound boron enolate. DFT calculations and control experiments revealed that the stereoselectivity is controlled
据报道,通过在无过渡金属的条件下直接酮化锂酮烯醇盐进行三取代乙烯基硼酸酯的空前的立体选择性合成。烯醇酸锂的立体有择CO硼化反应是通过C结合的硼烯醇盐由羰基诱导的1,3-金属盐重排触发的。DFT计算和控制实验表明,立体选择性受空间位阻的控制。使用新开发的方法可以方便地合成各种立体有择的三取代乙烯基硼酸酯,以及几种四取代乙烯基硼酸酯。基于立体定向乙烯基硼酸酯的转化,有效地获得了烯雌酚的单一异构体。