in tetrahydrofuran reaction of CO with (LiTMEDA)(CpV(C3H5)2) in THF (Ar); formation of 1,5-hexadiene in the reaction soln., extn. of the residue with toluene, filtering off the solid and drying to give Li2(CpV(CO)3), evapn. of the filtrate to dryness and subliming the residue in a high vacuum at 80°C to give CpV(CO)4;

in tetrahydrofuran reaction of CO with (LiTMEDA)(CpV(C3H5)2) in THF (Ar); formation of 1,5-hexadiene in the reaction soln., extn. of the residue with toluene, filtering off the solid and drying to give Li2(CpV(CO)3), evapn. of the filtrate to dryness and subliming the residue in a high vacuum at 80°C to give CpV(CO)4;