Zn in tetrahydrofuran addn. of VCl3 and Zn in THF to a soln. of indenyl lithium in THF at 0°C, refluxing for 15 h; evapn. to dryness, sublimation in vacuo, recrystn. of the sublimate (toluene-hexane), washing of the crystals, drying at 20°C in vacuo;

CH3Li in tetrahydrofuran; diethyl ether under N2, addn. of ether soln. of MeLi to THF soln. of indene (15 min, stirred, gas evolution), addn. of vanadium complex (prepared from refluxing of VCl3 in THF) at room temp., color change; evapn. to dryness, residue sublimed on oil bath up to 180°C for 2.5h, crystn., elem. anal.;

I2 in toluene under N2, I2 dissolved in toluene, addn. of (ind)2V, soln. heated just up to boiling; filtered, stored at room temp. for 24h, crystn., filtered, mother liquor stored a few hours at -20°C, then several hours in dry ice, additional crystn., elem. anal.;