n-BuLi in not given n-BuLi in hexane added dropwise to ligand in Et2O at 0°C; warmed to room temp.; stirred overnight; filtered; ppt. washed (Et2O); dried invac.; added to ZrCl4; C5H5Li added; mixt. of three Zr complexes obtaine d; sepd. by fractional crystn.; (C5H5)(C5HMe2Ph2)ZrCl2 contg. (C5H5)2ZrCl2 impurity obtained; detd. by NMR spectra;

1: aq. NaBH4 / methanol 2: aq. HCl / ethanol / Heating 3: aq. NaBH4 / methanol 4: aq. HCl View Scheme

N-bromosuccinmide

in benzene 12 h; Heating;