Thiazolium-Catalyzed Additions of Acylsilanes: A General Strategy for Acyl Anion Addition Reactions
作者:Anita E. Mattson、Ashwin R. Bharadwaj、Andrea M. Zuhl、Karl A. Scheidt
DOI:10.1021/jo060699c
日期:2006.7.1
utilizing N-heterocyclic carbenes (NHCs) derived from thiazolium salts has been developed for the generation of carbonyl anions from acylsilanes. Synthetically useful 1,4-diketones and N-phosphinoyl-α-aminoketones have been prepared in good to excellent yields via NHC-catalyzed additions of acylsilanes to the corresponding α,β-unsaturated systems and N-phosphinoylimines. These organocatalytic reactions
The Thiazolium-Catalyzed Sila-Stetter Reaction: Conjugate Addition of Acylsilanes to Unsaturated Esters and Ketones
作者:Anita E. Mattson、Ashwin R. Bharadwaj、Karl A. Scheidt
DOI:10.1021/ja0318380
日期:2004.3.3
A new acyl anion additionreaction between acylsilanes and alpha,beta-unsaturated conjugate acceptors promoted by a nucleophilic organic catalyst has been disclosed. The 1,4-dicarbonyl products produced in this reaction are highly useful synthons. Neutral carbenes (or zwitterions) generated in situ from commercial thiazolium salts are used as effective catalysts for the reaction which is in contrast
Visible-Light Photoredox-Catalyzed Divergent 1,2-Diacylation and Hydroacylation of Alkenes with Carboxylic Acid Anhydride
作者:Youkang Zhou、Lirong Zhao、Mingyou Hu、Xin-Hua Duan、Le Liu
DOI:10.1021/acs.orglett.3c01787
日期:2023.7.21
efficient entry to 1,4-dicarbonyl compounds bearing all-carbonquaternarycenters, exhibiting a broad substrate scope and high functional group compatibility. Hydrocarbonylaltion of alkenes can also be realized by simply introducing a proton source to the reaction system. Mechanism investigations support a radical addition/radical-polar crossover cascade.
Direct incorporation of two carbonyl groups into a double bond by diacylation is achieved for the first time via visible-light catalysis. Key to success is that N(n-Bu)4+ not only associates with the alkyl anion to avoid protonation, but also activates the α-keto acid to undergo electrophilic addition. The metal-free, redox-neutral and regioselective symmetric and unsymmetric 1,2-dicarbonylation of
通过可见光催化,首次实现了通过二酰化将两个羰基直接结合到双键中。成功的关键是 N( n -Bu) 4 +不仅与烷基阴离子缔合以避免质子化,而且还激活α-酮酸进行亲电加成。烯烃的无金属、氧化还原中性和区域选择性对称和不对称 1,2-二羰基化具有许多应用的潜力。