Role of molar-ratio, temperature and solvent on the Zn/Cd 1,2,4-triazolate system with novel topological architectures

Five members of the Zn/Cd triazolate family, [Zn(TAZ)(OAc)](n) (1), [Zn-4(TAZ)(6)(OAc)(2)](n) (2), [Cd3Cl3(TAZ)(3)(DMF)(2)](n) (3), [CdCl2(TAZ)](n)center dot n(H2O) (4) and [Cd2Cl(mu(4)-AmTAZ)(2)(mu-AmTAZ)](n) (5), have been synthesized from TAZ/AmTAZ and corresponding metal salts, where TAZ, AmTAZ and DMF are 1,2,4-triazole, 3-amino-1,2,4-triazole and N,N'-dimethylformamide, respectively. X-ray analysis shows that all compounds except 4 manifest interesting 3D frameworks with novel topologies. Compounds 1 and 2 are temperature-and-solvent controlled assemblies and possess 3D (3,4,6)-connected (3.7(2))(2)(3(2).4.7(3))(3(2).4.7(6).8(6)) topology and 3D (3,6)-connected (4.8(2))(3)(8(3))(4(6).8(6).12(3)) topology, respectively. However, compounds 3 and 4 are molar-ratio-dependent compounds. The framework of 3 is a 3D (3,4,5)-connected one with (4.10(2))(4.6(2))(2)(4(3).6(2).8)(2)(6(4).10(6)) topology, in which the 1D channels are filled with coordinated DMF, while only a 1D chain-like motif is formed in 4. In addition, a 3D (4,6)-connected (3.4(2).5(2).6)(2)(3(2).4(2).5(4).6(5).7(2))(3(2).4(4).5(4).6(4).7) topology is observed in the framework of 5, where AmTAZ is used instead of TAZ in the syntheses of compounds 1-4. Solid state measurements reveal that all these coordination polymers are thermostable and luminescent under ambient conditions.