Enhancing Ru(II)‐Catalysis with Visible‐Light‐Mediated Dye‐Sensitized TiO
<sub>2</sub>
Photocatalysis for Oxidative C−H Olefination of Arene Carboxylic Acids at Room Temperature
作者:Suman Dana、Purusattam Dey、Siddappa A. Patil、Mahiuddin Baidya
DOI:10.1002/asia.201901718
日期:2020.3.2
Erythrosine B sensitized TiO2 photocatalysis has been combined with Ru(II)-catalysis to accomplish an oxidativeolefination/annulation of benzoic acids with activated olefins under mild conditions that tolerates useful functionalities, such as halides, free hydroxy, acetamido, etc. The morphology of the photocatalyst is unaffected during the reaction and it can be reused. Mechanistic studies favor
Under rhodium(III)-catalyzed conditions, a broad range of benzoic acids reacted with acrylates successfully to provide phthalides through the direct functionalization of a C–H bond followed by β-hydride elimination and intramolecular Michael addition. The reaction provides an alternative strategy for the construction of diverse and useful phthalide derivatives from readily available starting materials
Ruthenium-Catalyzed Oxidative C–H Bond Alkenylations in Water: Expedient Synthesis of Annulated Lactones
作者:Lutz Ackermann、Jola Pospech
DOI:10.1021/ol201563r
日期:2011.8.19
Ruthenium-catalyzed cross-dehydrogenative C-H bond alkenylations occurred efficiently in environmentally benign water, which was exploited for an oxidative phthalide synthesis with ample scope. Mechanistic studies provided strong evidence for the oxidative alkenylation to proceed by an irreversible C-H bond metalation via acetate assistance.
Recyclable and Reusable [RuCl<sub>2</sub>(<i>p</i>-cymene)]<sub>2</sub>/Cu(OAc)<sub>2</sub>/PEG-400/H<sub>2</sub>O System for Oxidative C–H Bond Alkenylations: Green Synthesis of Phthalides
作者:Hong Zhao、Tinli Zhang、Tao Yan、Mingzhong Cai
DOI:10.1021/acs.joc.5b01388
日期:2015.9.4
[RuCl2(p-cymene)](2) in a mixture of poly(ethylene glycol) (PEG-400) and water is shown to be an extremely efficient catalyst for the cross-dehydrogenative C-H bond alkenylation reaction between benzoic acids and alkenes. The reaction could be conducted at 80 degrees C using Cu(OAc)(2). H2O as oxidant, yielding a variety of phthalide derivatives in good to excellent yields. More importantly, both [RuCl2(p-cymene)](2) and Cu(OAc)(2) in the PEG-400/H2O system could be easily recycled and reused six times without any loss of catalytic activity.