in tetrahydrofuran byproducts: LiCl; under Ar, THF soln. of V-compd. and 3 equiv. of Li-compd. were mixed, stirring for 24 h; soln. was evapd. in vac., residue was taken in toluene, LiCl was centrifuged off, soln. was cooled to -18 °C, two types of crystals were sepd. with several times washing with n-pentane, recrystn. twice from toluene, drying in vac., elem. anal.;

byproducts: LiCl, THF; under Ar;

in diethyl ether 1 mol of complex was slowly added to an ether soln. of 2 mol RMgCl at -15°C, after 1 h the temp. was raised to room temp. (Ar atm.);; dioxane was added, ppt. was extd. with pentane; elem. anal.;;

in tetrahydrofuran 1 mol of complex was slowly added to an THF soln. of 2 mol RMgCl at -15°C, after 1 h the temp. was raised to room temp. (Ar atm.);; dioxane in Et2O was added, evapd., ppt. was washed with Et2O;;

in diethyl ether 1 mol of complex was slowly added to an ether soln. of 2 mol RMgCl at -15°C, after 1 h the temp. was raised to 0°C (Ar atm.);; dioxane in hexane was added, ppt. was filtered off, identified by ESR spectra;;

in acetonitrile inert atmosphere, Schlenk techniques; aq. Na(pic) soln. addn. to stirred mixt. of V-compd., NaO2CEt and MeCN, stirring overnight, NaCl ppt. filtration off, NEt4Cl addn. to filtrate, solvent removal (vac.), residue redissoln. (acetone), THF addn.; pptn. after a few on standing at room temp., ppt. filtration off, washing (THF), vac. drying; elem. anal.;

in acetone inert atmosphere, Schlenk techniques; slurry (V- and Na-compds., bpy and solvent) stirring overnight at room temp., NaCl ppt. filtration off, NBu4ClO4 addn. to filtrate, solvent removal (vac.), residue washing (Et2O), redissoln. (acetone); distn. (A4 molecular sieve), pptn. on large excess Et2O addn., ppt. filtration off, washing (Et2O), vac. drying; elem. anal.;

in acetone inert atmosphere, Schlenk techniques; slurry (V- and Na-compds., bpy and solvent) stirring overnight at room temp., NaCl ppt. filtration off, NBu4ClO4 addn. to filtrate, solvent removal (vac.), residue washing (Et2O), redissoln. (acetone); distn. (A4 molecular sieve), pptn. on large excess Et2O addn., ppt. filtration off, washing (Et2O), vac. drying; elem. anal.;

in acetone inert atmosphere, Schlenk techniques; slurry (V- and Na-compds., bpy and solvent) stirring overnight at room temp., NaCl ppt. filtration off, NBu4ClO4 addn. to filtrate, solvent removal (vac.), residue washing (Et2O), redissoln. (acetone); distn. (A4 molecular sieve), pptn. on large excess Et2O addn., ppt. filtration off, washing (Et2O), vac. drying; elem. anal.;

in acetone inert atmosphere, Schlenk techniques; slurry (V- and Na-compds., bpy and solvent) stirring overnight at room temp., NaCl ppt. filtration off, NBu4ClO4 addn. to filtrate, solvent removal (vac.), residue washing (Et2O), redissoln. (acetone); distn. (A4 molecular sieve), pptn. on large excess Et2O addn., ppt. filtration off, washing (Et2O), vac. drying; elem. anal.;