The role of free N-heterocyclic carbene (NHC) in the catalytic dehydrogenation of ammonia-borane in the nickel NHC system.

Enders' N-heterocyclic carbene (NHC) dehydrogenates ammonia-borane with a relatively low barrier, producing NH(2)BH(2) and NHC-(H)(2). The nickel NHC catalyst present in the reaction media can activate the NHC-(H)(2) produced to regenerate the free NHC and release H(2). The release of free NHC enables further dehydrogenation of ammonia-borane.

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