Catalytically competent Ir, Re, and Ru complexes H(2)L(1)-H(2)L(6) with dicarboxylic acid functionalities were incorporated into a highly stable and porous Zr(6)O(4)(OH)(4)(bpdc)(6) (UiO-67, bpdc = para-biphenyldicarboxylic acid) framework using a mix-and-match synthetic strategy. The matching ligand lengths between bpdc and L(1)-L(6) ligands allowed the construction of highly crystalline UiO-67 frameworks (metal-organic frameworks (MOFs) 1-6) that were doped with L(1)-L(6) ligands. MOFs 1-6 were isostructural to the parent UiO-67 framework as shown by powder X-ray diffraction (PXRD) and exhibited high surface areas ranging from 1092 to 1497 m(2)/g. MOFs 1-6 were stable in air up to 400 °C and active catalysts in a range of reactions that are relevant to solar energy utilization. MOFs 1-3 containing [Cp*Ir(III)(dcppy)Cl] (H(2)L(1)), [Cp*Ir(III)(dcbpy)Cl]Cl (H(2)L(2)), and [Ir(III)(dcppy)(2)(H(2)O)(2)]OTf (H(2)L(3)) (where Cp* is pentamethylcyclopentadienyl, dcppy is 2-phenylpyridine-5,4'-dicarboxylic acid, and dcbpy is 2,2'-bipyridine-5,5'-dicarboxylic acid) were effective water oxidation catalysts (WOCs), with turnover frequencies (TOFs) of up to 4.8 h(-1). The [Re(I)(CO)(3)(dcbpy)Cl] (H(2)L(4)) derivatized MOF 4 served as an active catalyst for photocatalytic CO(2) reduction with a total turnover number (TON) of 10.9, three times higher than that of the homogeneous complex H(2)L(4). MOFs 5 and 6 contained phosphorescent [Ir(III)(ppy)(2)(dcbpy)]Cl (H(2)L(5)) and [Ru(II)(bpy)(2)(dcbpy)]Cl(2) (H(2)L(6)) (where ppy is 2-phenylpyridine and bpy is 2,2'-bipyridine) and were used in three photocatalytic organic transformations (aza-Henry reaction, aerobic amine coupling, and aerobic oxidation of thioanisole) with very high activities. The inactivity of the parent UiO-67 framework and the reaction supernatants in catalytic water oxidation, CO(2) reduction, and organic transformations indicate both the molecular origin and heterogeneous nature of these catalytic processes. The stability of the doped UiO-67 catalysts under catalytic conditions was also demonstrated by comparing PXRD patterns before and after catalysis. This work illustrates the potential of combining molecular catalysts and MOF structures in developing highly active heterogeneous catalysts for solar energy utilization.

Pt nanoparticles of 2-3 nm and 5-6 nm in diameter were loaded into stable, porous, and phosphorescent metal-organic frameworks (MOFs 1 and 2) built from [Ir(ppy)(2)(bpy)](+)-derived dicarboxylate ligands (L(1) and L(2)) and Zr(6)(μ(3)-O)(4)(μ(3)-OH)(4)(carboxylate)(12) secondary building units, via MOF-mediated photoreduction of K(2)PtCl(4). The resulting Pt@MOF assemblies serve as effective photocatalysts for hydrogen evolution by synergistic photoexcitation of the MOF frameworks and electron injection into the Pt nanoparticles. Pt@2 gave a turnover number of 7000, approximately five times the value afforded by the homogeneous control, and could be readily recycled and reused.

Phosphorescent cyclometalated iridium tris(2-phenylpyridine) derivatives were designed and incorporated into coordination polymers as tricarboxylate bridging ligands. Three different crystalline coordination polymers were synthesized using a solvothermal technique and were characterized using a variety of methods, including single-crystal X-ray diffraction, PXRD, TGA, IR spectroscopy, gas adsorption measurements, and luminescence measurements. The coordination polymer built from Ir[3-(2-pyridyl)benzoate](3), 1, was found to be highly porous with a nitrogen BET surface area of 764 m(2)/g, whereas the coordination polymers built from Ir[4-(2-pyridyl)benzoate](3), 2 and 3, were nonporous. The (3)MLCT phosphorescence of each of the three coordination polymers was quenched in the presence of O(2). However, only 1 showed quick and reversible luminescence quenching by oxygen, whereas 2 and 3 exhibited gradual and irreversible luminescence quenching by oxygen. The high permanent porosity of 1 allows for rapid diffusion of oxygen through the open channels, leading to efficient and reversible quenching of the (3)MLCT phosphorescence. This work highlights the opportunity of designing highly porous and luminescent coordination polymers for sensing other important analytes.

A new metal-organic framework (MOF)-templated method has been developed for the synthesis of a metal oxide nanocomposite with interesting photophysical properties. Fe-containing nanoscale MOFs are coated with amorphous titania, then calcined to produce crystalline Fe(2)O(3)/TiO(2) composite nanoparticles. This material enables photocatalytic hydrogen production from water using visible light, which cannot be achieved by either Fe(2)O(3) or TiO(2) alone or a mixture of the two.

Porous cross-linked polymers (PCPs) with phosphorescent [Ru(bpy)(3)](2+) and [Ir(ppy)(2)(bpy)](+) building blocks were obtained via octacarbonyldicobalt (Co(2)(CO)(8))-catalyzed alkyne trimerization reactions. The resultant Ru- and Ir-PCPs exhibited high porosity with specific surface areas of 1348 and 1547 m(2)/g, respectively. They are thermally stable at up to 350 °C in air and do not dissolve or decompose in all solvents tested, including concentrated hydrochloric acid. The photoactive PCPs were shown to be highly effective, recyclable, and reusable heterogeneous photocatalysts for aza-Henry reactions, α-arylation of bromomalonate, and oxyamination of an aldehyde, with catalytic activities comparable to those of the homogeneous [Ru(bpy)(3)](2+) and [Ir(ppy)(2)(bpy)](+) photocatalysts. This work highlights the potential of developing photoactive PCPs as highly stable, molecularly tunable, and recyclable and reusable heterogeneous photocatalysts for a variety of important organic transformations.