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

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