Metallo-phosphorylation of alkynes: reaction of alkynes with Cp2Zr(1-butene)(PR3) and chlorophosphateElectronic supplementary information (ESI) available: experimental procedures and NMR data. See http://www.rsc.org/suppdata/cc/b3/b308595c/
Factors Affecting the Unusual Reactivity Order in the β-Hydrogen Abstraction of Dialkylzirconocenes
作者:Ei-ichi Negishi、Thinh Nguyen、John P. Maye、Daniele Choueiri、Noriyuki Suzuki、Tamotsu Takahashi
DOI:10.1246/cl.1992.2367
日期:1992.12
Competitive β-hydrogen abstraction of “mixed” dialkylzirconocenes and kinetic measurements of decomposition of methyl(alkyl)zirconocenes reveal unexpected relative reactivity of alkyl groups as β-hydrogen donors, such as s-Bu > t-Bu ≥ Et > n-Bu > i-Bu, which correlate well in most cases with the reactivity order of: β-methyl > β-methylene > β-methine. Some mechanistically crucial features of the reaction are also discussed.
Structural determination of the first zirconocene–olefin complex, i.e., Cp2Zr(PhCH=CHPh)(PMe3), by X-ray crystallography is presented. Zirconium–olefin complexes such as ethylene and butene complexes can be selectively prepared in high yields from dialkylzirconocenes. On treatment of Cp2Zr(CH3)(PhCH2CH2) with, PMe3 a styrene complex 5 was obtained in good yield.
The reaction of zirconocene–alkyne complexes prepared from Cp2ZrCl2 with BuLi and an alkyne with Mo(CO)6 yielded 2,3-disubstituted-5-ethylcyclopentenone derivatives by incorporation of once elimina...
Double carbonylation of zirconocene–alkyne complexes
作者:Shizue Mito、Tamotsu Takahashi
DOI:10.1039/b501545f
日期:——
Zirconoceneâalkyne complexes prepared from Cp2ZrBu2, phosphines and alkynes reacted with CO to give double carbonylation products, 4-hydroxycyclobuten-1-one derivatives after hydrolysis.
由 Cp2ZrBu2、膦和炔制备的锆烯炔络合物与 CO 反应,水解后得到双羰基化产物 4-羟基环丁烯-1-酮衍生物。
Bis(η5-cyclopentadienyl)- and bis(η5-indenyl)metallacycles of titanium and zirconium from methylenecyclopropanes by oxidative coupling
Methylenecyclopropane (1a) reacts with bis(trimethylphosphane)titanocene (8) and (η2-1-butene)(trimethylphosphane)zirconocene (12a) via olefin complexes; e.g. 9, in a [2+2] cycloaddition to afford the metallacyclopentane derivates 10, 13 and 14. In contrast, a [3+2] cycloaddition reaction is observed with bis(η5-lndenyl)(η2-1-butene)(trimethylphosphane)zirconium (12b) to furnish the 1-zircona-4-methylenecyclohexane