Tan Boon Beng, Hu Ming, Ge Shaozhong
Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543, Singapore, Singapore.
Angew Chem Int Ed Engl. 2023 Aug 7;62(32):e202307176. doi: 10.1002/anie.202307176. Epub 2023 Jul 3.
Ligand-controlled regiodivergent cobalt-catalyzed ring-opening dihydroboration of arylidenecyclopropanes is developed to access synthetically versatile skipped diboronates with catalysts generated in situ from Co(acac) and dpephos or xantphos. A variety of arylidenecyclopropanes reacted with pinacolborane (HBpin) to form the corresponding 1,3- or 1,4-diboronates in high isolated yields and with high regioselectivity. Skipped diboronate products from these reactions can undergo various transformations to allow selective installation of two different functional groups along alkyl chains. Mechanistic studies suggest that these reactions combine cobalt-catalyzed ring-opening hydroboration of arylidenecyclopropanes and hydroboration of homoallylic or allylic boronate intermediates.
开发了配体控制的区域发散性钴催化的亚芳基环丙烷的开环二氢硼化反应，以通过由Co(acac)和dpephos或xantphos原位生成的催化剂获得具有合成通用性的跳跃式二硼酸酯。多种亚芳基环丙烷与频哪醇硼烷(HBpin)反应，以高分离产率和高区域选择性形成相应的1,3-或1,4-二硼酸酯。这些反应生成的跳跃式二硼酸酯产物可进行各种转化，以便沿着烷基链选择性地安装两个不同的官能团。机理研究表明，这些反应结合了钴催化的亚芳基环丙烷的开环硼氢化反应以及高烯丙基或烯丙基硼酸酯中间体的硼氢化反应。
