Syntheses, structures and reactions of some new benzyl-substituted   cyclopentadienyl titanium complexes

doi:10.1016/S0022-328X(97)00382-3

CORC > 北京大学 > 化学与分子工程学院

	Syntheses, structures and reactions of some new benzyl-substituted cyclopentadienyl titanium complexes
	Qian, YL ; Huang, JL ; Yang, JM ; Chan, ASC ; Chen, WC ; Chen, XP ; Li, GS ; Jin, XL ; Yang, QC
刊名	有机金属化学杂志
	1997
关键词	TRANSITION-METALS CRYSTAL-STRUCTURE ORGANOTITANIUM CHEMISTRY TITANOCENE ISOMERIZATION (R-CP)2TICL2/R&apos DICHLORIDES MGX
DOI	10.1016/S0022-328X(97)00382-3
英文摘要	Twenty eight new benzyl-substituted cyclopentadienyl titanium complexes have been synthesized. Among them, five typical molecular structures have been studied by X-ray analysis. It was found that in the preparation of ortho-MeO-containing benzyl-substituted titanium complexes, when both two substituents on benzylic carbon atom are Et or more large group, titanoxacycle complexes are always formed. The cyclization was promoted by the presence of halides. The activity order of halides for the cyclization is: LiI-NaI > LiBr-Br-2 > NaBr-KI > KBr > I-2. High temperature is favourable to the cyclization. At 80 degrees C, the normal ortho-MeO benzyl-substituted cyclopentadienyl titanium complex 26 may be spontaneously converted into metallocyclic complex 19. The position of the MeO group on the benzene ring is the key factor to the cyclization. In the case of meta- and para-MeO benzyl-substituted titanium complexes 23 and 25, there was no possibility to form a titanoxacycle complex, such as 19, because the MeO group is too far from titanium. A probable mechanism involving a four-membered transition state was proposed. (C) 1997 Elsevier Science S.A.; Chemistry, Inorganic & Nuclear; Chemistry, Organic; SCI(E); 40; ARTICLE; 2; 263-279; 547
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/257887]
专题	化学与分子工程学院
推荐引用方式 GB/T 7714	Qian, YL,Huang, JL,Yang, JM,et al. Syntheses, structures and reactions of some new benzyl-substituted cyclopentadienyl titanium complexes[J]. 有机金属化学杂志,1997.
APA	Qian, YL.,Huang, JL.,Yang, JM.,Chan, ASC.,Chen, WC.,...&Yang, QC.(1997).Syntheses, structures and reactions of some new benzyl-substituted cyclopentadienyl titanium complexes.有机金属化学杂志.
MLA	Qian, YL,et al."Syntheses, structures and reactions of some new benzyl-substituted cyclopentadienyl titanium complexes".有机金属化学杂志 (1997).