Asymmetric Synthesis of Dihydropyranones via Gold(I)‐Catalyzed Intermolecular [4+2] Annulation of Propiolates and Alkenes
作者:Hanbyul Kim、Su Yeon Choi、Seunghoon Shin
DOI:10.1002/anie.201807514
日期:2018.10
Intermolecular asymmetric gold catalysis involving alkyne activation presents a significant challenge due to its distinct mechanistic mode from other metals. Herein, we report a highly enantioselective synthesis of α,β‐unsaturated δ‐lactones from [4+2] annulation of propiolates and alkenes in upto 95 % ee. Notably, for the desired chiral recognition, the choice of 1,1,2,2‐tetrachloroethane as solvent
涉及炔烃活化的分子间不对称金催化由于其不同于其他金属的机理模式而提出了重大挑战。在本文中,我们报道了在高达95%ee的条件下,由丙酸酯和烯烃的[4 + 2]环化反应生成的高对映选择性的α,β-不饱和δ-内酯。值得注意的是,为获得所需的手性识别,选择1,1,2,2-四氯乙烷作为溶剂至关重要。此外,阴离子表面活性剂(十二烷基硫酸钠)提高了在环丙基金卡宾中间体的发散性方面的产物选择性。