REACTIONS OF TERT-BUNC WITH HALIDES OF TITANIUM(IV), HAFNIUM(IV), VANADIUM(III), NIOBIUM(IV), MOLYBDENUM(V) AND TUNGSTEN(VI) - INSERTION INTO METAL-HALOGEN BONDS AND LIGAND DISPLACEMENT-REACTIONS

t-BuNC inserts into a metal-halogen bond of TiCl4, HfCl4, VCl3 and [NbCl4(thf)2] to give [TiCl3{C(Cl)NBu-t} (CNBu-t)]2,(HfCl3{C(Cl)NBu-t}-(CNBu-t)]2, [VCl2(C(Cl)NBu-t)(CNBu-t)2]2 and [NbCl3{C(Cl)NBu-t}-(CNBu-t)]2, respectively. [MoCl4(thf)2] and WCl6 do not give inserted products, but rather [MoCl3(CNBu-t)3]Cl and trans-[WCl4(CNBu-t)2]. Treatment of these inserted products and [MX4{C(X)NBu-t} (CNBu-t)]2 (M = Nb or Ta, X = Cl or Br) with lithium quinolin-8-olate (Li[8-quin]), sodium diethyldithiocarbamate (Na[dtc]) or Ph2PCH2CH2PPh2 (dppe) causes displacement of terminal t-BuNC in all cases and in some cases of the iminomethyl ligand as well. Thus obtained are the complexes [TiCl2{C(Cl)NBu-t}(8-quin)], TiCl4(dppe)], [TiCl2(dtc)2], [HfCl2{C(Cl)NBu-t}(8-quin)], [HfCl3{C(Cl)NBu-t}(dppe)], [Hf(dtc)4], [VCl{C(Cl)NBu-t}(8-quin)], [V(dtc)4], [NbCl2 {C(Cl)NBu-t}(8-quin)]2, [NbCl{C(Cl)NBu-t}(dtc)2]2, [MX3{C(X)NBu-t}(8-quin)] (M = Nb or Ta, X = Cl or Br), [NbX2{C(X)NBu-t}(dtc)2] and [TaX3{C(X)NBu-t}(dtc)]2. Ta2Br10 gives TaBr3(dtc)2 on treatment with Na[dtc]. Physical data for these complexes are discussed in terms of their structure. © 1979.