Cationic Imido Alkylidene Complexes of Molybdenum Supported by β-Diketonate and β-Diketiminate Ligands

Reaction of Mo(NAr)(CHCMe2Ph)(OTf)2(DME) (Ar
= 2,6-i-Pr2C6H3) with the lithium salt of various β-diketonates
and β-diketiminates leads to complexes of the type Mo(NAr)(CHCMe2Ph)(L)(OTf) (L = β-diketonate or β-diketiminate).
Treatment of these compounds with NaB[3,5-(CF3)2C6H3]4 in
dichloromethane affords rare examples of cationic imido
alkylidene complexes. The solid-state structures of two of these
compounds, {Mo(NAr)(CHCMe2Ph)(TMHD)(THF)}{B[3,5-(CF3)2C6H3]4} and {Mo(NAr)(CHCMe2Ph)(ArCl-Nacnac)}{B[3,5-(CF3)2C6H3]4} (TMHD = tetramethylheptanedionato,
ArCl-Nacnac = [2,6-Cl2C6H3NC(Me)]2CH), have been determined by X-ray diffraction, and their reactivity with ethylene
and other simple olefins has been explored.