in not given byproducts: C2H4, C2H6; react. hydrocarbon soln. 1,2-W2Et2(NMe2)4 with acid anhydride at room temp.; crystn. from benzene or hexane;

in not given byproducts: C2H4, C2H6; react. hydrocarbon soln. 1,2-W2Et2(NMe2)4 with acid anhydride at room temp.; crystn. from benzene or hexane;

in hexane W2Et2(NMe2)4/hexane soln. was cooled to -20°C and 4.05 equiv. isopropylalc. was added, stirred 30 min., degassed from HN(CH3)2; frozen at -198°C and addn. of 2-butyne(2.1 equiv.); rapidly warmed to 0°C, stirred 5min./room temp.; evapn., extn. with pentane, filtered, cooled to -78°C.. After 48h yielded a solid by removing of the supernatant liquid. Detected by NMR and IR;

in not given byproducts: C2H4, C2H6; react. hydrocarbon soln. 1,2-W2Et2(NMe2)4 with acid anhydride at room temp.; crystn. from benzene or hexane;