The interactions of transition metal tetrafluoroborates with 2,tWutiditte N-oxide(L) in organic solvents were studied, under various conditions. A number of adducts of the types [CrL,](BF&, [ML,] (BF.& (M = Fe, Cu, Zn, Cd), [CoL.,(FBF,)] -(BF,)*H@ and L&LzNiL,, were isolated and characterized. In most cases, these compounds are similar to the corresponding metal perchlorate complexes (including the square-planar Fe'+ complex, which is partially spin-paired (S = I; peff = 3.55 p&J). The oruy differences are that the new Co2+ complex involves coordinated FBF,, while the 4:1 Co(CrO,), analog contains exclusively ionic Clod, and that, whereas the diamagnetic, square-planar [NiL4] (ClO,), complex remains unchanged for a long time before dimerizing to the paramagnetic [LfliL2-N&1 (QO& with the NiL,, analog the monomeric species is unstable, dimerizing within a few hours. 7?tese differences were attributed to the significantly smaller steric hindrance exerted by BF, relative to ClO+ In addition to the preceding adducts, a number of products of the types [L3CoF2CoL3
] IBF,J,, [(F,BF,)L(ROH)MF,M(ROHJL(F,BF,)I 1R = CH3 for M = Mn; R = C,H, for M = Ni) and MnLF(BF4).4MnF2 were isolated. Formation of MF(BF,) or MF, is accompanied by elimination of BF, *L from the initially formed adducts. This reaction seems to be favored when the initial adduct of L with M(BFd)2 involves cooordinated tetrajluoroborato ligands [l] .