乙基环己烷 、 [(η5-pentamethylcyclopentadienyl)(NO)(neopentyl)(η3-CH2CHCHPh)] 以
further solvent(s) 为溶剂,
以46%的产率得到[(η5-pentamethylcyclopentadienyl)(NO)(CH2CH2C6H11)(η3-CH2CHCHPh)]
参考文献:
名称:
Intermolecular C–H Activations of Hydrocarbons Initiated by Cp*M(NO)(CH2CMe3)(η3-CH2CHCHPh) Complexes (M = Mo, W)
摘要:
Thermolysis of Cp*W(NO)(CH2CMe3)(eta(3)-CH2CHCHPh) (1) at 55 degrees C leads to the loss of neopentane and the formation of the 16e eta(2)-allene intermediate complex Cp*W(NO)(eta(2)-CH2=C=CHPh) (A), which has been isolated as its 18e PMe3 adduct (2). Further support for the existence of the allene intermediate A is provided by the thermolysis of 1 in cyclohexene, which affords Cp*W(NO)(H)(eta(3)-CH2C(3-cyclohexenyl)CHPh) (3) as the principal organometallic product. In the presence of n-heptane, n-octane, or n-pentane, A effects C-H activations of the hydrocarbons exclusively at their terminal carbons and forms 18e Cp*W(NO)(n-alkyl)(eta(3)-CH2CHCHPh) complexes (4-6). Similarly, treatments of 1 with mesitylene, methylcyclohexane, and ethylcyclohexane all lead to the corresponding primary sp(3) C-H activation products (7-9). Complex mixtures of organometallic products result when 1 is thermolyzed in p-xylene and toluene, reflecting the occurrence of both aryl and benzylic C-H activations. Interestingly, the aryl C-H activations do not afford the expected Cp*W(NO)(aryl)(eta(3)-CH2CHCHPh) products but rather their Cp*W(NO)(H)[eta(3)-CH(aryl)CHCHPh] isomers resulting from aryl-H exchange. The thermal chemistry of the molybdenum analogue of 1, namely Cp*Mo(NO)(CH2CMe3)(eta(3)-CH2CHCHPh) (14), has also been investigated, and it turns out to be much more limited in scope. When 14 is heated at 35 degrees C in neat mesitylene for 22 h, it results in conversion to the mesitylene-activated product Cp*Mo(NO)(CH2C6H3-3,5-Me-2)(eta(3)-CH2CHCHPh) (15) in low yield, but thermolyses of 14 in other hydrocarbons do not produce tractable organometallic materials. The results of DFT calculations on the model reaction of CpW(NO)(eta(2)-CH2=C=CHMe) with propane confirm that the rate-determining step is the cleavage of a propane C-H bond and that the lower energy anti conformers favor terminal activation by 11.5 kJ/mol. All new complexes have been characterized by conventional spectroscopic and analytical methods, and the solid-state molecular structures of most of them have been established by X-ray crystallographic analyses.