0000000000648725
AUTHOR
Christopher J. Roberts
Ammonia Activation by a Nickel NCN-Pincer Complex featuring a Non-Innocent N-Heterocyclic Carbene: Ammine and Amido Complexes in Equilibrium
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 insig…
Comment on “Crystallographic Snapshot of an Arrested Intermediate in the Biomimetic Activation of CO2”
Out of focus: A recent Communication published in this journal describes the synthesis of [nBu4 N]HCO3 . The authors performed a single-crystal X-ray study that revealed a putative species described as an incipient hydroxide ion engaging in a long, and presumably weak, interaction with CO2 . Our recent exploration of the coordination chemistry of CO2 with small ions leads us to believe that such an exceptional bonding situation is unlikely. Instead, we argue that the crystal structure is that of [nBu4 N]O2 CCH3 and therefore not representative of the bulk powder from the synthesis.
CCDC 1405505: Experimental Crystal Structure Determination
Related Article: Rudy M. Brown, Javier Borau Garcia, Juuso Valjus, Christopher J. Roberts, Heikki M. Tuononen, Masood Parvez, and Roland Roesler|2015|Angew.Chem.,Int.Ed.|54|6274|doi:10.1002/anie.201500453
CCDC 1036823: Experimental Crystal Structure Determination
Related Article: Juha Hurmalainen, Michael A. Land, Katherine N. Robertson, Christopher J. Roberts, Ian S. Morgan, Heikki M. Tuononen and Jason A. C. Clyburne|2015|Angew.Chem.,Int.Ed.|54|7484|doi:10.1002/anie.201411654
CCDC 1405504: Experimental Crystal Structure Determination
Related Article: Rudy M. Brown, Javier Borau Garcia, Juuso Valjus, Christopher J. Roberts, Heikki M. Tuononen, Masood Parvez, and Roland Roesler|2015|Angew.Chem.,Int.Ed.|54|6274|doi:10.1002/anie.201500453