Expanding the Scope of C−H Amination through Catalyst Design
journal contributionposted on 01.12.2004, 00:00 by Christine G. Espino, Kristin Williams Fiori, Mihyong Kim, J. Du Bois
Analysis of the mechanism for Rh-mediated C−H amination has led to the development of a remarkably effective dinuclear Rh catalyst derived from 1,3-benzenedipropionic acid. This unique complex, Rh2(esp)2, is capable of promoting both intra- and intermolecular C−H oxidation reactions, and in all cases is superior to Rh2(O2CtBu)4. For the first time, C−H insertion is described with urea and sulfamide substrates to give 1,2- and 1,3-diamine derivatives, respectively. In addition, intermolecular amination of benzylic and secondary C−H bonds is shown to proceed efficiently even under conditions in which the starting alkane is employed as the limiting reagent.