Well-Defined Silica Grafted Molybdenum Bis(imido) Catalysts for Imine Metathesis Reactions

Novel site-isolated tetracoordinated molybdenum complexes possessing bis­(imido) ligands, [(Si–O)2Mo­(NR)2] (R = t-Bu, 2,6-C6H3-i-Pr2), were immobilized on partially dehydroxylated silica (SiO2‑200) by a rigorous surface organometallic chemistry protocol. The newly developed materials adorned with bis­(imido) functional units, which were previously exploited mainly as spectator ligands on silica-supported olefin metathesis molybdenum catalysts, are found to be efficient heterogeneous catalytic systems for imine cross metathesis under mild conditions.