[2 + 2] Cycloaddition Products of Zirconium and Hafnium Hydrazinediides with Allenes and Heteroallenes and Their Thermally Induced Rearrangements

摘要: Reactions of the hydrazinediido complexes [M(N2TBSNpy)(NNPh2)(py)] (M = Zr (1a), Hf (1b)) with (hetero)allenes result in a variety [2 + 2] cycloaddition products general type [M(N2TBSNpy)(κ2N,E-(E(═E′R)NNPh2)(py)] (E CH2, S; E′ CH, N; R alkyl, aryl). The reaction [Zr(N2TBSNpy)(NNPh2)(py)] (1a) 1 molar equiv phenyl or mesityl isothiocyanate at room temperature yields [Zr(N2TBSNpy)(κ2N,S-SC(═NAr)NNPh2)(py)] (Ar (2a), (2b)). Reacting hydrazinediides allenes results formation metallaazacyclobutanes [M(N2TBSNpy)(κ2N,C-N(NPh2)CH2C═CH(R))(py)] Zr, Ph (4a), cyclohexyl (5a), methyl (6); M Hf, (4b), (5b)). Subsequent heating revealed different reactivity patterns: complex (2a) forms isomerization product [Zr(N2TBSNpy)(κ2N,S-SC(═NNPh2))NPh] (3), retaining N–N bond hydrazide. In contr...