Zi Quan-Xing, Shu Wei
Guangming Advanced Research Institute, Department of Chemistry, and Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and Technology, Shenzhen Grubbs Institute, Shenzhen, Guangdong, 518055, P. R. China.
State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing, Jiangsu, 210093, P. R. China.
Adv Sci (Weinh). 2024 Dec;11(48):e2409592. doi: 10.1002/advs.202409592. Epub 2024 Oct 28.
Enantioenriched unsymmetric dialkyl carbinol derivatives are of importance in natural products, bioactive molecules, and functional organic materials. However, the catalytic asymmetric synthesis of dialkyl carbinol derivatives remains challenging due to the similar steric and electronic properties of two alkyl substituents. Herein, an unprecedented synthesis of chiral dialkyl carbinol ester derivatives from Ni-catalyzed reductive-oxidative relay cross-coupling of two alkenes is developed for the first time. The reaction features the use of enol esters and unactivated alkenes as two different alkyl equivalents to undergo head-to-tail and enantioselective alkyl-alkyl cross-coupling. The reaction undergoes two-electron reduction and single electron oxidation in the presence of both reductants and oxidants. The use of an allyl bromide as single electron acceptor is crucial for the success of this non-trivial asymmetric cross-coupling, providing a new reaction mode for asymmetric alkyl-alkyl bond-forming event in the absence of stoichiometric alkyl electrophiles.
对映体富集的不对称二烷基甲醇衍生物在天然产物、生物活性分子和功能性有机材料中具有重要意义。然而，由于两个烷基取代基的空间和电子性质相似，二烷基甲醇衍生物的催化不对称合成仍然具有挑战性。在此，首次开发了一种前所未有的方法，通过镍催化的两种烯烃的还原-氧化接力交叉偶联反应合成手性二烷基甲醇酯衍生物。该反应的特点是使用烯醇酯和未活化的烯烃作为两种不同的烷基等价物，进行头对尾的对映选择性烷基-烷基交叉偶联。在还原剂和氧化剂的存在下，反应经历双电子还原和单电子氧化。使用烯丙基溴作为单电子受体对于这种不平凡的不对称交叉偶联反应的成功至关重要，为在没有化学计量的烷基亲电试剂的情况下形成不对称烷基-烷基键提供了一种新的反应模式。
