Reactions of Stable N-Heterocyclic Silylenes with Ketones and 3,5-Di-tert-butyl-o-benzoquinone

The reactions of L [PhC(NtBu)(2)SiCl] and L' [CH{(C=CH2)(CMe)(2,6-iPr(2)C(6)H(3)N)(2)}Si] with monoketones and quinone have been examined. The reaction of L with 2-adamantanone furnishes a [1 + 2]-cycloaddition product 1, whereas with 3,5-di-tert-butyl-o-benzoquinone leads to the [1 + 4]-ycloaddition product 2. The treatment of L' with 3,5-di-tert-butyl-o-benzoquinone gives [1 + 4]-cycloaddition product 3, and the reaction with acylferrocene yields compound 4. Compounds 1-4 were characterized by single crystal X-ray structural analysis, NMR spectroscopy, EI-MS spectrometry, and elemental analysis.