6533b829fe1ef96bd128a2db

RESEARCH PRODUCT

Ammonia Activation by a Nickel NCN-Pincer Complex featuring a Non-Innocent N-Heterocyclic Carbene: Ammine and Amido Complexes in Equilibrium

Javier Borau GarciaRudy M. BrownChristopher J. RobertsHeikki M. TuononenJuuso ValjusRoland RoeslerMasood Parvez

subject

Coordination spheretyppiliganditN-heterosykliset karbeenitammoniakkiPhotochemistryammoniaCatalysisAmidinenikkelikomopleksichemistry.chemical_compoundDeprotonationPolymer chemistrypincer ligandsN-heterocyclic carbenesta116bond activationChemistryLigandTransition metal carbene complexnickel complexGeneral ChemistryGeneral Medicinesidoksen aktivointiOxidative additionPincer movementCarbene

description

A Ni0-NCN pincer complex featuring a six-membered N-heterocyclic carbene (NHC) central platform and amidine pendant arms was synthesized by deprotonation of its NiII precursor. It retained chloride in the square-planar coordination sphere of nickel and was expected to be highly susceptible to oxidative addition reactions. The Ni0 complex rapidly activated ammonia at room temperature, in a ligand-assisted process where the carbene carbon atom played the unprecedented role of proton acceptor. For the first time, the coordinated (ammine) and activated (amido) species were observed together in solution, in a solvent-dependent equilibrium. A structural analysis of the Ni complexes provided insight into the highly unusual, non-innocent behavior of the NHC ligand. peerReviewed

https://doi.org/10.1002/ange.201500453