Pd(II)-catalyzed C–H functionalization of nondirected arenes has been realized using an inexpensive and easily accessible type of bidentate S,O-ligand. The catalytic system shows high efficiency in the C–Holefination reaction of electron-rich and electron-poor arenes. This methodology is operationally simple, scalable, and can be used in late-stage functionalization of complex molecules. The broad
Reactivity of Electron-Deficient Alkynes on Gold Nanoparticles
作者:Antonio Leyva-Pérez、Judit Oliver-Meseguer、Jose R. Cabrero-Antonino、Paula Rubio-Marqués、Pedro Serna、Saud I. Al-Resayes、Avelino Corma
DOI:10.1021/cs400362c
日期:2013.8.2
Propiolates cyclotrimerize in the presence of catalytic amounts of gold nanoparticles to give aryl benzoates in high yields and with turnover frequencies of thousands per hour. Types of alkynes other than propiolates do not react, and, if molecular oxygen is present and dissociated by the gold nanoparticles, electron-rich arenes engage with the propiolate to form a new C-C bond. The activation of propiolates and electron-rich arenes to form C-C bonds, beyond gold-catalyzed Michael additions, constitutes a new example of how and where gold nanoparticles modify the electronic density of unsaturated C-C bonds and opens the door to future transformations.