反应详情

Following the literature procedure [b], 3.30 ml (5.33 mmol, 1.60 M) of an ethereal solution of methyllithium are slowly added dropwise at -78° C. to a suspension of 1.03 g (2.66 mmol) of zirconocene dichloride (Example 10) in 50 ml of diethyl ether. The mixture is allowed to warm slowly to room temperature in a cold bath and is then stirred at room temperature for a further 5 hours. The solvent is removed in vacuo, and the colorless residue is extracted with 3×50 ml of pentane. The combined pentane solutions are evaporated and kept at -25° C. to crystallize. Removal of the solvent and drying in an oil-pump vacuum gives 700 mg (76%) of dimethylzirconocene as a colorless, crystalline powder.

1. customThe solvent is removed in vacuo
2. extractionthe colorless residue is extracted with 3×50 ml of pentane
3. customThe combined pentane solutions are evaporated
4. customkept at -25° C.
5. customto crystallize
6. customRemoval of the solvent
7. customdrying in an oil-pump vacuum