In Search of Catalytically Active Species in the Surfactant-Mediated Biphasic Alkene Epoxidation with Mimoun-Type Complexes

[figure: see text] A biphasic protocol for the catalytic olefin epoxidation with Mimoun-type complexes [MoO(O2)2(OPR3)] (1) was recently patented by BASF. Density-functional calculations have been carried out to identify potentially active species in addition to the parent complex 1. It has been found that the (mu 2,eta 1:eta 2-O2)-bridged dimer [MoO(O2)2(OPR3)]2 is significantly less reactive than the monomer. The calculations show that the parent complex is strongly activated by protons coordinating with the peroxo functionalities.