Hydrogen isotope exchange with highly active iridium(I) NHC/phosphine complexes: a comparative counterion study.

Herein, we present a range of substrates that undergo hydrogen isotope exchange with an iridium(I) N-heterocyclic carbene/phosphine complex bearing the less coordinating tetrakis[3,5-bis(trifluoromethyl)phenyl] borate counterion and compare these with labelling using the equivalent, more established hexafluorophosphate complex. The changes in reactivity and selectivity of these complexes in a series of solvents are examined. Copyright (C) 2016 John Wiley & Sons, Ltd.