Functional Modeling of Ni,Fe Hydrogenases: A Nickel Complex in an N,O,S Environment.

In the solid state an octahedral while in solution probably a square-planar coordination geometry is found for the central metal atom in the NiII thiosemicarbazone complex cation 1. The dissociation of the phenol groups lends 1 hydrogenase-like activity. Dissolved in EtOH through which a stream of D2 gas is bubbled, 1-Cl2 undergoes H/D exchange with a turnover of 7.5, a reaction which corresponds to the activation of H2.