Na in tetrahydrofuran 0.145 mmol of C5H5SiMe3 was added to a mixt. of sodium sand (130 mmol) and THF; after approx. 5 d the stirred soln. was cooled (0°C) and ZrCl4 (65 mmol) was added slowly over 0.5 h; the mixt. was stirred at 20°C for 2 h;; removal of THF in vacuo, followed by extn. with boiling hexane, filtration, concn. of the filtrate and cooling to -30°C;;

in dichloromethane mixt. refluxed for 20 h; volatiles evapd.; residue extd. with benzene, filtered; volatiles evapd. under vac.;

trifluoroacetic acid T=60°C; 3 h; Heating;

in ethanol react. of RuCl2*2H2O with (trimethylsilyl)cyclopentadiene (3 equiv., reflux, 4-6 h);

in dichloromethane mixt. refluxed for 24 h; reaction mixt. filtered; hexane added and filtered again; volatiles evapd.; residue washed with hexane and dried;

in benzene byproducts: SiMe3Cl; Cp-compd. added to soln. of TiCl4 with stirring, then stirred for 30 min.; filtered, washed with benzene, dried, sublimed at 120-130.degreeC/0.1 Torr;

sodium hydride 1.) THF, 1 h, room temp.; 2.) THF, 12 h, reflux; Yield given. Multistep reaction;