文摘
By employing S(CH<sub>2sub>CH<sub>2sub>S<sup>–sup>)<sub>2sub> (tpdt) and O(CH<sub>2sub>CH<sub>2sub>S<sup>–sup>)<sub>2sub> (opdt) as bridging ligands, two nickel–iron and two nickel–ruthenium heterodimetallic complexes, [Cp*M(μ-1κ<sup>3sup>SSS′:2κ<sup>2sup>SS-tpdt)Ni(dppe)][PF<sub>6sub>] (1, M = Fe; 3, M = Ru) and [Cp*M(μ-1κ<sup>3sup>SSO:2κ<sup>2sup>SS-opdt)Ni(dppe)][PF<sub>6sub>] (2, M = Fe; 4, M = Ru) (Cp* = η<sup>5sup>-C<sub>5sub>Me<sub>5sub>; dppe = Ph<sub>2sub>P(CH<sub>2sub>)<sub>2sub>PPh<sub>2sub>), were obtained by a one-pot synthetic method and were identified by spectroscopy and X-ray crystallography. At 1 atm of CO, the pendant oxygen atom dissociated from the iron or ruthenium center and rapidly transferred to the nickel center when a CO molecule attacked the iron or ruthenium center in 2 and 4. However, there was no similar reaction occurring in 1 and 3 with the pendant sulfur atom. We confirmed the solid-state structure of the CO complex [Cp*Fe(t-CO)(μ-1κ<sup>2sup>SS:2κ<sup>3sup>SSO-opdt)Ni(dppe)][PF<sub>6sub>] (5), which represents a possible configuration in the CO-inhibited state of [NiFe]-hydrogenase and exhibits no catalytic activity in electrochemical proton reduction.