Dicyclopentadienylzirconium dichloride

The combination of dicyclopentadienylzirconium dichloride and silver perchlorate activates armed glycosyl sulfoxides in dichloromethane between -20 °C and room temperature, but only very simple acceptors were studied [335]. Other Lewis and Bronsted acids studied include the environmentally benign europium, lanthanum and ytterbium triflates [336], certain polyoxometallates [337], sulfated zirconia [338] and Nafion H [338]. 

Aluminoxanes suppressed side reactions involving hydrogen transfer. They also formed cyclic structures with starch, giving copolymers that were coated with crystalline polyethylene. A catalyst composed of dicyclopentadienylzirconium dichloride and trimethylaluminium permitted polymerization of ethylene on starch in a toluene suspension at 60 °C for 2h.2806 Graft copolymerization of methyl methacrylate onto starch was also performed with an acetylacetone-copper(II) complex in trichloroacetic acid.2807 The grafting yield and efficiency were proportional to the initiator concentration up to 7.0 x 10-3 mole/L. 

In a similar manner, 1,7-octadiene and 1,6-heptadiene can be reductively cyclized to give, after acidic workup of the resulting carbometalation product (see Section 1.5.8.4.4,), cisjtrans mixtures of 1,2-dimethylcyclohexane and 1,2-dimethylcyclopentane, respectively, with opposite preference of the diastereomersls. The reaction uses 1.5-fold equimolar amounts of dibutyl-magnesium and is catalyzed by dicyclopentadienylzirconium dichloride. If oxidative workup is used instead of hydrolysis, the corresponding diols are obtained15. Several other examples of this type have been reported82. 

Dicyclopentadienylzirconium dichloride. See Zirconocene dichloride Dicyclopentenyl acetate (5-ene isomer). See Greenyl acetate... 

Zirconium turnings. See Zirconium Zirconocene dichloride CAS 1291-32-3 EINECS/ELINCS 215-066-8 Synonyms Dicyclopentadienylzirconium dichloride Zirconium, dichloro-di-pi-cyclopentadienyl-... 

Hydrozirconation of olefins can be readily accomplished by the use of the hydride XLIV derived from the relatively inexpensive reagent, dicyclopentadienylzirconium dichloride (Hart and Schwartz, 1974). Very... 

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