cross‐dehydrogenative coupling of arene carboxylicacids with olefins is reported with ruthenium(II) catalyst employing air and water as green oxidant and solvent, respectively. It offers a robust synthesis of valuable phthalide molecules. A one‐pot sequential strategy is also disclosed to access Heck‐type products that are apparently difficult to make directly from arene carboxylicacids.
Electrochemically driven, Cp*Ir(III)-catalyzed regioselective annulative couplings of benzoicacids with alkynes have been established herein. The combination of iridium catalyst and electricity not only circumvents the need for stoichiometric amount of chemical oxidant, but also ensures broad reaction compatibility with a wide array of sterically and electronically diverse substrates. This electrochemical
as a powerful strategy for organometallic catalysis, and yet electrocatalytic C−Hactivation is restricted to strongly N‐coordinating directing groups. The first example of electrocatalytic C−Hactivation by weak O‐coordination is presented, in which a versatileruthenium(II) carboxylate catalyst enables electrooxidative C−H/O−H functionalization for alkyne annulations in the absence of metal oxidants;
电催化已被认为是有机金属催化的有力策略,但是电催化CH活化仅限于强N配位的导向基团。给出了通过弱O配位进行电催化C-H活化的第一个例子,其中通用的羧酸钌(II)催化剂可在没有金属氧化剂的情况下实现炔烃环化的电氧化C / H / OH功能化。从而利用可持续的电力作为唯一的氧化剂。机械学的见解为简便的有机金属CH钌钌化和关键钌(0)中间体的有效电化学再氧化提供了有力的支持。
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
One-Pot Sequential N-Heterocyclic Carbene/Rhodium(III) Catalysis: Synthesis of Fused Polycyclic Isocoumarins
作者:So Won Youn、Huen Ji Yoo
DOI:10.1002/adsc.201700072
日期:2017.7.3
A one‐pot sequential N‐heterocyclic carbene–rhodium (NHC‐Rh) catalysis is described, demonstrating the compatibility of NHC and Rh catalysts. N‐Heterocyclic carbene‐catalyzedaerobicoxidation of benzaldehydes and subsequent rhodium(III)‐catalyzedoxidative coupling/annulation with multiple bonds enabled the formation of two C–O bonds and one C–C bond in a single pot. This operationally easy, one‐pot