Alkynes react with organoborons under a CO atmosphere in the presence of a rhodium(I) catalyst to afford mainly 5-aryl-2(5H)-furanones, α,β-unsaturated ketones, and indanones. The product selectivity can be tuned by modifying the reaction conditions.
Versatile and practical: Intermolecularhydroacylation of internalalkynes takes place in the presence of Ru catalysts together with HCO2Na and Xantphos to give the corresponding conjugated enones. Aromatic aldehydes with or without coordinating groups could be used in the present catalytic system. The solid Ru/CeO2 catalysts can be recycled for several times without significant decreases in yield
多功能和实用:内部炔烃的分子间加氢酰化反应在Ru催化剂与HCO 2 Na和Xantphos共同存在下进行,从而得到相应的共轭烯酮。具有或不具有配位基团的芳族醛可以用于本催化体系中。固体Ru / CeO 2催化剂可以循环使用几次,而收率没有明显降低(参见方案)。
Rhodium(I)-Catalyzed Carbonylative Arylation of Alkynes with Arylboronic Acids Using Formaldehyde as a Carbonyl Source
The rhodium(I)-catalyzed reaction of alkynes with arylboronic acids in the presence of formaldehyde resulted in a carbon monoxide gas-free carbonylative arylation to yield α,β-enones. The simultaneous loading of phosphine-ligated and phosphine-free rhodium(I) complexes is required for efficient catalysis, which catalyze the abstraction of a carbonyl moiety from formaldehyde (decarbonylation) and its
Stereodivergent Access to Enantioenriched Epoxy Alcohols with Three Stereogenic Centers via Ruthenium-Catalyzed Transfer Hydrogenation
作者:Zhifei Zhao、Prasanta Ray Bagdi、Shuang Yang、Jinggong Liu、Weici Xu、Xinqiang Fang
DOI:10.1021/acs.orglett.9b01789
日期:2019.7.19
technique of stereodivergent reaction on racemic mixtures (stereodivergent RRM) was employed for the first time in ruthenium complex catalyzed transferhydrogenation of racemic epoxy ketones, providing a new and very simple method that allows access to enantioenriched epoxy alcohols with three stereogenic centers in a one-step fashion. The protocol features simplereaction conditions, practical operation