Reductive dehydroxy coupling of 2-(hydroxymethyl)indenes to prepare ethano-bridged bis(2-indenyl) ansa-titanocenes
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چکیده
منابع مشابه
Reductive dehydroxy coupling of 2-(hydroxymethyl)indenes to prepare ethano-bridged bis(2-indenyl) ansa-titanocenes
New examples of ansa-titanocenes derived from 1,2-bis(2-indenyl)ethane have been prepared. The titanium-mediated reductive coupling of 2-(hydroxymethyl)indenes provided a convenient method for substrate dimerization. Alkyl substitution of the indene ring at C(3) improved the regioselectivity of the reductive coupling to provide the ethylene bis(2-indenyl)ansa-ligands in 29–62% yield.
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207 Novel olefin-linked biscylopentadienylligands have been prepared by McMurry coupling reactions of benzoyland acetyl-cyclopentadienyl sodium. Reactions of the disodium salts with TiC1 4 or TiCl 3 • 3THF afford the alkene-bridged ansa-titanocene dichlorides. 13C-NMR shifts of the bridge carbon atoms do not indicate any interaction between the olefin 'IT-system and the metal.
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Metallation of a variety of α,ω-dienes has been explored with an η(9),η(5)-bis(indenyl)zirconium sandwich compound and an ansa-titanocene dinitrogen complex. The η(9),η(5)-bis(indenyl)zirconium sandwich compound, (η(9)-C(9)H(5)-1,3-Pr(2))(η(5)-C(9)H(5)-1,3-(i)Pr(2))Zr, served as an isolable source of Negishi's reagent and readily formed a kinetic mixture of cis and trans diastereomers of the co...
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ژورنال
عنوان ژورنال: Journal of Organometallic Chemistry
سال: 1999
ISSN: 0022-328X
DOI: 10.1016/s0022-328x(99)00024-8