4-Phenol diazoniumsalts undergo Pd-catalyzed Heck reactions with various styrenes to 4′-hydroxy stilbenes. In almost all cases higher yields and fewer side products were observed, compared to the analogous 4-methoxy benzene diazoniumsalts. In contrast, the reaction fails completely with 2- and 3-phenol diazoniumsalts. For these substitution patterns the methoxy-substituted derivatives are superior
Dual ligand-promoted palladium-catalyzed nondirected C–H alkenylation of aryl ethers
作者:Biao Yin、Manlin Fu、Lei Wang、Jiang Liu、Qing Zhu
DOI:10.1039/d0cc00940g
日期:——
DirectC-H functionalization of aryl ethers remains challenging owing to their low reactivity and selectivity. Herein, a novel strategy for nondirected C-Halkenylation of aryl ethers promoted by a dual ligand catalyst was demonstrated. This catalytic system readily achieved the highly efficient alkenylation of alkyl aryl ethers (anisole, phenetole, n-propyl phenyl ether, n-butyl phenyl ether and benzyl
Synthesis of stilbene derivatives via visible-light-induced cross-coupling of aryl diazonium salts with nitroalkenes using –NO<sub>2</sub> as a leaving group
作者:Na Zhang、Zheng-Jun Quan、Zhang Zhang、Yu-Xia Da、Xi-Cun Wang
DOI:10.1039/c6cc08182g
日期:——
The straightforward visible-light-induced synthesis of stilbene compounds from the cross-coupling of nitroalkenes and diazonium tetrafluoroborates under transition-metal-free conditions is described. The protocol uses green LEDs as light sources and eosin...