Small Molecule Activation Chemistry of Cu–Fe Heterobimetallic Complexes Toward CS2 and N2O

In this contribution, we report the reactivity of polar, unsupported Cu–Fe bonds toward small-molecule heteroallenes. Insertion of CS2 into the polar Cu–Fe bond of (IMes)­Cu-FeCp­(CO)2 proceeds at mild conditions and results in the simultaneous presence of two unprecedented CS2 binding modes (μ3:η4 and μ3:η3) in the same product. Reactivity between N2O and (NHC)­Cu-FeCp­(CO)2 complexes also is observed at mild conditions, resulting in migration of the cyclopentadienyl groups from Fe to Cu. Similar reactivity is observed for new (NHC)­Cu-FeCp*­(CO)2 analogues, whose structural characterization is reported here and reveals two semibridging Cu···CO interactions per molecule. Stoichiometric oxygen atom transfer from N2O to PPh3 was mediated by (IMes)­Cu-FeCp­(CO)2, indicating the presence of an N2O-activated intermediate that can be intercepted by exogenous reagents.