Copper porphyrin-catalyzed construction of ether bond by cross-dehydrogenative coupling of sp [3] C–H bond with phenols bearing electron-withdrawing groups (EWG) was described for the first time. A broad range of substrates afforded different acetals in moderate to excellent yields with good functional group tolerance. The developed method is not only suitable for phenol substrates with ortho-directing
The construction of C(sp<sup>3</sup>)–O bond via copper porphyrin catalyzed cross-dehydrogenative coupling reaction: Substituent and electronic effect of the catalysts
effect of copper porphyrin catalysts on the cross-dehydrogenativecoupling (CDC) reaction between the hydroxyl group of phenol substrates and C(sp3)-H bond have been investigated. Results showed that copper porphyrin bearing electron-withdrawing, bulky steric hindrance or heteroatom of pyridyl groups could increase the catalytic activity in the reaction. 5,10,15,20-(tetrakis(4-pyridyl)porphyrin)copper
Iron-Catalyzed Oxidative Direct α-C–H Bond Functionalization of Cyclic Ethers: Selective C–O Bond Formation in the Presence of a Labile Aldehyde Group
作者:Balaji D. Barve、Yang-Chang Wu、Mohamed El-Shazly、Michal Korinek、Yuan-Bin Cheng、Jeh-Jeng Wang、Fang-Rong Chang
DOI:10.1021/ol5004115
日期:2014.4.4
Iron catalyzed oxidative coupling of salicylaldehydes with cydic ethers proceeded through the direct a-C H functionalization of ethers, forming the corresponding acetals in moderate to excellent yields. This is the first example of iron catalyzed selective C-O bond formation in the presence of a sensitive aldehyde moiety.