A practical and efficient construction of C–O bonds via oxidative cross-coupling reaction of aldehydes and ethers has been realized under open air. When 2 mol% copper was used as the catalyst, various α-acyloxy ethers were obtained with up to 93% isolated yield.
The copper-catalyzedformation of C–Obonds by oxidativecoupling of benzylicalcohols with ethers was realized in open air. A series of α-acyloxy ethers were obtained in good yields with aqueous tert-butyl hydroperoxide as the oxidant.
Cyclic ethers to esters and monoesters to bis-esters with unconventional coupling partners under metal free conditions via sp<sup>3</sup> C–H functionalisation
作者:Ganesh Majji、Srimanta Guin、Saroj K. Rout、Ahalya Behera、Bhisma K. Patel
DOI:10.1039/c4cc05050a
日期:——
An efficient metal free oxidative esterification of sp(3) C-H bonds (adjacent to an oxygen atom) in simple solvents like 1,4-dioxane, tetrahydropyran, tetrahydrofuran and ethyl acetate has been achieved using terminal aryl alkenes and alkynes as the ArCOO(-) sources.
Generation of bis-Acyl Ketals from Esters and Benzyl Amines Under Oxidative Conditions
作者:Ganesh Majji、Suresh Rajamanickam、Nilufa Khatun、Sourav Kumar Santra、Bhisma K. Patel
DOI:10.1021/jo502903d
日期:2015.4.3
Treatment of benzylamines with esters at an elevated temperature are expected to give amides. However, in the presence of TBAI/TBHP, esters possessing a methylene carbon alpha-to oxygen with benzylamines provide bis-esters rather than the expected amides. Benzylamines under oxidative conditions generate less nucleophilic carboxylates, which couples at the sp(3) C-H bonds of esters and cyclic ethers to give bis-acyl ketals and alpha-acyloxy ethers, respectively.