Schwartz cyclopentadienyl zirconium

Schwartz s Reagent Bis(cyclopentadienyl)zirconium chloride hydride Zirconium, chlorodi-B-cyclopentadienylhydro- (8) Zirconium, chlorobis(ii5-2,4-cyclopentadien-1-yl)hydro- (9) (37342-97-5)... 

Formation of methylcyclopropane complexes and reactions of these metal alkyls competes with direct conversion of the homoallylmetal complex. Thus 1,2-hydrozirconation of 1,3-dienes with Schwartz s reagent [bis(cyclopentadienyl)zirconium chloride hydride] leads to homoallyl-zirconium complexes 1 which upon treatment with V-bromosuccinimide give the corresponding l-bromobut-3-enes 2 and the isomeric (bromomethyl)cyclopropanes 3 via intramolecular ring closure. ... 

The Schwartz reagent has been replaced by bis(cyclopentadienyl)zirconium(IV) hydride triflate [Cp2Zr(H)OTf], which displays the advantages over the Schwartz reagent, such as less tendency for aggregation and the higher reactivity of hydride due to the weak coordination ability of triflate anion. ... 

Di(cyclopentadienyl)zirconium hydrochloride, Schwartz s reagent , hydrochloride allows hydrozircona-tion. The resulting vinyl zirconium species 2.137 behave similarly to the vinylalanes, and undergo coupling in a similar manner (Scheme 2.47). 

Acylzirconocene chloride derivatives are easily accessible in a one-pot procedure through the hydrozirconation of alkene or alkyne derivatives with zirconocene chloride hydride (Schwartz reagent) [Cp2Zr(H)Cl, Cp = cyclopentadienyl] and subsequent insertion of carbon monoxide (CO) into the alkyl— or alkenyl—zirconium bond under atmospheric pressure (Scheme 5.1) [2],... 

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