Solvothermal synthesis of discrete cages and extended networks comprising {Cr(III)3O(O2CR)3(oxime)3}2− (R = H, CH3, C(CH3)3, C14H9) building blocks

The synthesis, structural and magnetic characterisation of a family of related Cr(III) cages are reported. Each member comprises {Cr(III)3O(O2CR1)3(R2-sao)3}2− (R1 = H, CH3, C(CH3)3, C14H9; R2 = Me, Ph, tBu, C10H8) triangles linked by Na+ cations, resulting in either the discrete complexes [H3O][NEt4]2[NaCr(III)6O2(O2C-C14H9)6(Naphth-sao)6] (1) and [Na4Cr(III)6O2(O2CC(CH3)3)6(3,5-di-tBu-sao)6(MeCN)6] (3); or the extended networks [H3O]2[Na2Cr(III)6O2(O2CH)6(Ph-sao)6(MeCN)2(H2O)2]n·4MeCN (2); [H3O][Na3Cr(III)6O2(O2CCH3)6(Me-sao)6(MeCN)]n (4) and [Na2Cr(III)3O(O2CCH3)3(Me-sao)3(H2O)6]n·3MeCN (5). Magnetic susceptibility data obtained for 2 and 4 reveal weak antiferromagnetic exchange between the Cr(III) ions in the triangles.