Zirconocene complexes bearing novel 3-dimethylamino-1,2-dihydropentalene derived ligand systems.
نویسندگان
چکیده
Coupling of the N,N-dimethylacrylamides 6a-c with cyclopentadienide resulted in the formation of the substituted 3-dimethylamino-1,2-dihydropentalnenes 2a-c. Deprotonation followed by metallation with CpZrCl(3)·DME gave the substituted zirconocenes 12a-c. The reaction of 3-dimethylamino-1-methyl-dihydropentalene 2a with ZrCl(2)(NMe(2))(2)·2THF resulted in a unique coupling between a pair of the aminodihydropentalene derivatives to yield an unsymmetrically bridged novel ansa-zirconocene framework (9a). Treatment of the 1,1-dimethyl-substituted substrate 2b with this Zr-amido reagent in contrast resulted in a clean deprotonation and formation of the unbridged bis(dimethylaminohydropentalenyl)ZrCl(2) complexes 10b. The compounds 2a, 9a, meso-10b, 12a and 12c were characterized by X-ray diffraction.
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عنوان ژورنال:
- Dalton transactions
دوره 39 41 شماره
صفحات -
تاریخ انتشار 2010