Artificial hydrogenases

Decades of biophysical study on the hydrogenase (H2ase) enzymes have yielded sufficient information to guide the synthesis of analogs of their active sites. Three families of enzymes serve as inspiration for this work: the [FeFe]-H2ases, [NiFe]-H2ases, and [Fe]-H2ases, all of which feature iron centers bound to both CO and thiolate. Artificial H2ases affect the oxidation of H2 and the reverse reaction, the reduction of protons. These reactions occur via the intermediacy of metal hydrides. The inclusion of amine bases within the catalysts is an important design feature that is emulated in related bioinspired catalysts. Continuing challenges are the low reactivity of H2 toward biomimetic H2ases.