in acetonitrile N2 atm.; cooling (-78°C), heating (30 min, -40°C), stirring (2 h); extraction (toluene, CH3CN), centrifugation, addn. of toluene, pentane, Et2O, drying (vac., 40°C); elem. anal.;

in benzene byproducts: NaBr; (N2), to a susp. of W-complex in benzene added organic compound in benzene, stirred for 5 h at 50-60°C; filtered, soln. evaporated to dryness in vac.;

water in tetrahydrofuran byproducts: W2(CO)6(C5H5)2, Ni(W(CO)3(C5H5))2(P(C6H5)3)2; educts reacted in THF at ambient temp. for 2-10 min, water added; filtered, washed with acetone, recrystd. from CH2Cl2-hexane; elem. anal.;

in tetrahydrofuran a soln. of Na-salt in THF was added to Ni-complex, the mixt. stirred at room temp. for 10 min, H2O was added (over 1-2 min), solid was sepd. by filtration; solid was washed with H2O, then acetone, crystd. from CH2Cl2-hexane at -20°C, washed with hexane, dried in vac.; to the filtrate contg. W2(CO)6(Cp)2 (IR) hexane was added, on standing for 14 d crystn. of W-Cl and Ni-complex; elem. anal.;

in acetonitrile N2 atm.; cooling (-78°C), heating (30 min, -40°C), stirring (2 h); extraction (toluene, CH3CN), centrifugation, addn. of toluene, pentane, Et2O, drying (vac., 40°C); elem. anal.;