Catalytic Transformations of Alkynes into either α-Alkoxy or α-Aryl Enolates: Mannich Reactions by Cooperative Catalysis and Evidence for Nucleophile-Directed Chemoselectivity
作者:Rajkumar Lalji Sahani、Manoj D. Patil、Sachin Bhausaheb Wagh、Rai-Shung Liu
DOI:10.1002/anie.201806883
日期:2018.11.5
The catalytic formation of gold enolates from alkynes, nitrones, and nucleophiles is described, and their Mannich reactions result in nucleophile‐directed chemoselectivity through cooperative catalysis. For 1‐alkyn‐4‐ols and 2‐ethynylphenols, their gold‐catalyzed nitrone oxidations afforded N‐containing dihydrofuran‐3(2H)‐ones with syn selectivity. The mechanism involves the Mannich reactions of gold
描述了由炔烃,硝酮和亲核试剂催化形成烯醇金的过程,它们的曼尼希反应通过协同催化导致亲核试剂导向的化学选择性。1-炔-4-醇及2- ethynylphenols,得到含有N-二氢呋喃-3-(2-他们的黄金-催化的硝酮氧化ħ) -酮与顺式 选择性。该机制涉及通过O-H-N氢键基序的金烯酸酯与亚胺的曼尼希反应。对于芳氧基乙炔来说,它们的金烯醇盐会与硝酮选择性反应,生成受C-H-O氢键控制的3-亚烷基苯并呋喃-2-酮。