Protonation of Coordinated Dinitrogen Using Protons Generated from Molecular Hydrogen

A new strategy has been developed to synthesize N-H bonds from coordinated N-2 in trans-[W(dppe)(2)(N-2)(2)] (1) using protons generated from H-2 in the presence of (C6F5) 3B and 2,2,6,6-tetramethylpiperidine, under normal experimental conditions or upon sonication. The complexes [(dppe)(2)WH(NNH2)][HB(C6F5)(3)] (2) and [FW(dppe)(2)(NNH2)][HB(C6F5)(3)] (3) have been successfully isolated and characterized using standard analytical and spectroscopic methods. We have also monitored the progress of the reaction of complex 1 with a frustrated Lewis pair dihydrogen adduct (FLP-H-2) using standard spectroscopic techniques by following the signatures of the reactants and the products. The results of the current studies are promising for fixing N-2 into ammonia by using H-2, under normal experimental conditions, in the near future.