Phenyltungsten trichloride

Phenyltungsten trichloride-AIuminum chloride, CeHsWCIa AICI3 (1 1). 

The 1 1 complex derived from phenyltungsten trichloride and aluminium trichloride is an effective catalyst for diene-cyclobutane metathetical interconversions. Thus, the tetracyclic compounds (291) and (292) were respectively isomerized to the dienes (293) and (294). Rather more surprising was the virtually quantitative formation of the cyclobutanoid compound (296) from (295). Reaction of norbomadiene with 2,2 -bipyridyl(cyclo-octa-l,5-diene)nickel at 25°C yielded the exo-trans,endo-metal o-carbocyclic (297) which, on treatment with an activated olefin (e.g. maleic anhydride), afforded the cyclo-dimer (298 predominantly exo-trans,endo) in good yield by displacement of the hydrocarbon moiety. Catalytic conversions can also be achieved. 

Phenyltungsten trichloride aluminum chloride Ethylene derivs. from cyclopropanes Retrocarbene reaction... 

Ethylcyclopropane in 5 1 dimethyl ether-chlorobenzene containing 1 1 phenyltungsten trichloride-aluminum chloride kept 2.5 hrs. at room temp, in a sealed tube 1-butene. Y 73% based on startg. m. consumed. F. e. s. P. G. Gassman and T. H. Johnson, Am. Soc. 98, 6057 (1976). 

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