38443-89-9Relevant articles and documents
Synthesis, X-ray structure, and nucleophilic properties of mixed bis(diene)tantalum complexes Ta(η5-C5R5)(η4-C 4H6)(η4-C6H10)
Okamoto, Takuji,Yasuda, Hajime,Nakamura, Akira,Kai,Kanehisa,Kasai, Nobutami
, p. 2266 - 2273 (2008/10/08)
Mixed bis(diene) complexes of tantalum have been synthesized in a stepwise manner either by reaction of TaCl2L(butadiene) of supine (exo) geometry (L = C5Me5, C5H5) with (2,3-dimethyl-2-butene-1,4-diyl)magnesium or by reaction of TaCl2L(2,3-dimethylbutadiene) of supine geometry with (2-butene-1,4-diyl)magnesium. In the former reaction, the initial geometry of the coordinated diene changes from supine to prone (endo) while, in the latter reaction, the supine geometry of the 2,3-dimethylbutadiene ligand was maintained. Ta(C5Me5) (prone-butadiene) (supine-2,3-dimethylbutadiene) (6a) thus obtained crystallizes in space group Pbca with a = 14.173 (3) ?, b = 16.524 (3) ?, c = 15.344 (3) ?, and Z = 8. The reaction of 6a with 2,4-dimethyl-3-pentanone revealed the higher reactivity of the butadiene unit lying prone compared with dimethylbutadiene lying supine.