Bulky Siloxyaluminum Alkyls as Models for Al2Me6-Treated Silica Gel Surfaces. Characterization of a Dimethylaniline-Stabilized Dimethylaluminum Cation
摘要:
Reaction of a particularly bulky silanol, (2,4,6-Me3C6H2)(3)SiOH, with Al2Me6 gives, instead of the otherwise preferred unreactive binuclear siloxalanes with two siloxy bridges, a binuclear siloxalane with one siloxy and one methyl bridge, Me2Al(mu-OSi(2,4,6-Me3C6H2)(3))(mu-Me)AlMe2. This species reacts with zirconocene dichlorides under chloride/methyl exchange; with the cationizing reagent PhMe2NH+B(C6F5)(4)(-) it forms the B(C6F5)(4)(-) salt of the mononuclear cation AlMe2(NPhMe2)(2)(+).