Extended coordination frameworks incorporating heterobimetallic squares

The molecular structure of aluminium and iron(III) complexes with 3-phenyl and 3-(4-pyridyl) (HL) substituted acetylacetonate ligands is appreciably distorted. For AlL3 and FeL3 this shows that the orientation of the side pyridyl-N donor atoms lone pairs is about 90 and 135degrees which favours the assembly of heterobimetallic square patterns in Al(Fe)L-3 complexes with metal ions. This was employed for the modular construction of semi-regular heterobimetallic networks, in which the pyridyldiketonate ligands bridge pairs of Fe(Al)/Cd(Co) metal ions and support the structure of 1D and 2D coordination polymers. The unprecedented 2D structure of [Cd{AlL3}(CH3OH){NO3}(2)].2CHCl(3) and Cd{AlL3}(CH3OH)Br-2].2CHCl(3).2CH(3)OH is based upon plane tiling by a set of heterobimetallic squares and octagons, while [Cd{FeL3}(2)(NO3)(2)].2H(2)O and [Co{AlL3}2Cl(2)].4CHCl(3).2CH(3)OH are 1D polymers and exist as chains of heterobimetallic squares sharing opposite vertices.