Synthesis of layered (2-D) V-based bimetallic oxalates from non-aqueous media that cannot be synthesized from aqueous media

The reaction of (NBu4)3V(III)(ox)3] (1, ox = oxalate) and M(II) (M = Fe, Co, Ni, Cu) ions in MeCN, leads to the isolation of V-based coordination polymers of N(n-Bu)4]Fe(II)V(II)I(ox)3].0.30N(n-Bu)4](BF4)] (2), N(n-Bu)4]Co(II)V(III)(ox)3].0.75N(n-Bu)4](BF4)] (3), N(n-Bu)4]Ni(II)V(III)(ox)3].0.20N(n-Bu)4](BF4)].0.20MeCN (4), and N(n-Bu)4]Cu(II)V(III)(ox)2](BF4)2 (5) composition. Due to the lability of V(III)(ox)3]3- to dissociate ox2-, these compounds cannot be prepared from aqueous media. 5 is best described as N(n-Bu)4]V(III)Cu(II)(ox)2](BF4)2, and 2, 3, 4, and 5 are proposed to have a layered (2-D) motif for the MM(ox)x (x = 2, 3) extended framework. The V(III)Cu(II)(ox)2] composition of 5 is reported for the first time for a bimetallic oxalate. 2 shows a weak antiferromagnetic interaction between Fe(II), S = 2 and V(III), S = 1 ions (theta = -9.4 K) within the 2-D layers. 3 and 5 do not magnetically order above 2 K. 4 magnetically order as ferromagnets below 2.55 K taken as the onset of magnetization in chi'(T)], and has a glass transition temperature (chi'(max) at 1000 Hz) at 2.26 K.