| Porous metal-organic frameworks have attracted a lot of attention recently. Up now a large number of transition-metal ions have been used to construct MOFs, while MOFs based on Pb2+/Ln3+ ions are still rare. Generally, the choice of ligands is critical to obtain Pb/Ln-organic frameworks. Accordingly, two new rigid imidazolate/carboxylate functionalized ligands were designed and used for the assemble reactions with Pb2+/Ln3+ ions. Meanwhile, Co<sup>2+/Mn<sup>2+/Cu2+/Zn2+ based MOFs were synthesized via direct synthesis method and unusually solvent-mediated simultaneous structural transformation. Their structures and properties were characterized:1. Two new rigid imidazolate/carboxylate functionalized ligands, H3DPBI and H3DPBT（H3DPBI=5-（5,7-dioxoimidazo[4,5-f]isoindol-6（1H,5H,7H）-yl）isophthalicacid;H3DP BT=2-（5,7-dioxoi-midazo[4,5-f]isoindol-6（1H,5H,7H）-yl）terephthalic acid）) were designed, synthesiszed and characterized.2. Seven new MOFs were prepared through the reactions of between Pb2+/Eu3+/Tb3+ ions and H3DPBI,H3DPBT or H24-DPBB （4-（5,7-dioxopyrrolo[3,4-f]benzimidazole-6-yl）-benzoic acid） ligands:1-4 are Pb-based MOF and 5-7 are isostructural compounds containing Eu3+/Tb3+ ions.1-2 are based on H24-DPBB.1 exhibit 3D （3,3,8）-connected framework which is a new topology:（3.4.5） （42.6） （32.43.56.610.74.83）. Compounds 2 bears a 2D （6,3）-net structure with hcb topology.3 and 5-7 are based on H3DPBI.3 is a 1D chain compound.5-7 are isostructural compounds and have a 2D （4,4）-net layered structure.6 is capable of sensing acetone.4 is based on H3DPBT and displays a 2D （3,6）-connected neutral framework with kgd topology.All of these MOFs exhibit good thermal stabilities and favorable luminescent properties.3. [M2（BTC）（Cl）（DMA）3] （8和9） (M=Co<sup>2+/Mn<sup>2+,BTC3-=benzene-1,3,5-tricarboxylate, DMA=N,N-dimethylacetamide) obtained from the reactions between Co<sup>2+/Mn<sup>2+ and H3BTC in DMA feature a 3D srs framework in which 3-connected {Co2（COO）3} and BTC3- serve as SBUs and spacers, respectively. When exposed to DMA solution of Cu（NO3）2,8 and 9 were progressively transformed into heterometallic Co/Mn-Cu-HKUST-1 （[Co0.14Cu2.86（BTC）2]） （10） and ([Mno.o9Cu2.91BTC2] （12） via unusually solvent-mediated simultaneous structural transformation and partial transmetalation.10、12 represents the first heterometallic HKUST-1 derivative containing both Co<sup>2+/Mn<sup>2+ and Cu2+.However, when exposed to Zn（NO3）2 solution in DMA for longer time,8 retains its framework with limited metal-ion exchange, resulting in the formation of [Co1.93Zno.o7（BTC）（Cl）（DMA）3] （11）. The mechanism for such conversion is proposed based on systematic studies and the adsorption performances of thiophene compounds over Co-CuHKUST-1（10） were preliminary explored. |
