Remote coordination approach for electronic tuning of a rhodium(I)-N-heterocyclic carbene (NHC)-complex
摘要:
A simple Lewis acid coordination at the remote binding site installed within a modular N-heterocyclic carbene (NHC) ligated rhodium(I) complex could induce desired electronic influence and thereby enhance the activity of the complex in a model styrene hydroboration reaction.
Labile coordination approach for the modulation of the electronic properties of ruthenium(ii) and iridium(iii) complexes within an “N-heterocyclic carbene (NHC)–pyridyl” dynamic platform
Rhodium(III)-Catalyzed Activation and Functionalization of Pyridine C–H Bond by Exploring a Unique Double Role of “N-Heterocyclic Carbene–Pyridyl” Ligand Platform
作者:Ranjeesh Thenarukandiyil、Joyanta Choudhury
DOI:10.1021/acs.organomet.5b00157
日期:2015.5.26
A new rhodium(III)-catalyzed protocol for C-H activation and functionalization of poorly reactive pyridine backbones with the aid of in-built N-heterocyclic carbene ligand has been presented. Mechanistic investigations including the isolation and single crystal X-ray structural characterization of the pre- and postfunctionalized rhodium(III)-intermediates suggested a plausible pyridine-coordination effect in the present NHC-directed cyclometalative annulation of the C(3)-H bond of the pyridine rings with internal alkynes. The strategy enables us to overcome the challenges of functionalizing robust metal-C-NHC backbone concomitant with pyridine C-H activation under an oxidizing environment.