Decarboxylative 1,4-Addition of α-Oxocarboxylic Acids with Michael Acceptors Enabled by Photoredox Catalysis
作者:Guang-Zu Wang、Rui Shang、Wan-Min Cheng、Yao Fu
DOI:10.1021/acs.orglett.5b02392
日期:2015.10.2
Enabled by iridium photoredoxcatalysis, 2-oxo-2-(hetero)arylacetic acids were decarboxylatively added to various Michael acceptors including α,β-unsaturated ester, ketone, amide, aldehyde, nitrile, and sulfone at room temperature. The reaction presents a new type of acyl Michael addition using stable and easily accessible carboxylicacid to formally generate acyl anion through photoredox-catalyzed
Treatment of silyl enolates with methyllithium followed by an addition of galliumtrichloride afforded the corresponding gallium enolates. The reaction of the resulting gallium enolates with α-halo carbonyl compounds in the presence of triethylborane as a radical initiator provided 1,4-dicarbonyl compounds in good yields.
N-alkenoxypyridinium salts are widely used for the synthesis of α-functionalized ketones via umpolung strategy, such approaches are usually limited to special nucleophiles at high temperatures. Herein, we developed an alternative photoinduced N-heterocyclic carbene (NHC)- mediated functionalization of N-alkenoxypyridinium salts with various nucleophiles, including tetramethylammonium azide, secondary amines, aryl
Palladium-catalyzed coupling of amides and cyclopropanols for the synthesis of γ-diketones
作者:Lili Fang、Shuqi Jia、Shuaixin Fan、Jin Zhu
DOI:10.1039/d3cc02888g
日期:——
method has been developed for the coupling of amides and cyclopropanols to γ-diketones, through simultaneous C–N and C–C activation. Heteroatom ligand exchange and heteroatom-to-carbon ligation mode switching enable the achievement of molecular cross-coupling in an amide N-atom structural context-dependent manner, avoiding any stoichiometric organometallic reagent or base.
Light-Driven Three-Component Carbonylation of Aryl Halides Using Abundant Metal Carbonyl
作者:Quansheng Mou、Tongyu Han、Mingxin Liu
DOI:10.1021/acs.orglett.4c00211
日期:2024.3.22
Carbonyl compounds are widely found in various pharmaceutical intermediates and synthetic precursors. Herein we report a simple light-driven three-component aryl halide process for synthesizing a variety of carbonylation products, utilizing Co2(CO)8 as an abundant solid carbonyl source, in good to excellent yields. The products can easily be subjected to further functionalization in synthesis. Mechanism