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Aerobic photo-oxidation of sulfide into sulfoxide in water is of great interest in green chemistry. In this study, three highly stable Ir(III)–Zr(IV) metal–organic frameworks (Ir–Zr MOFs), namely Z...

Carbazole is an important compound in pharmaceuticals and functional materials. A new Pd(II) supramolecular cage-catalyzed protocol for the synthesis of multifunctional carbazoles from indoles is described through regioselective successive oxidative Heck reactions. This new protocol is highly efficient, with a low Pd (2.4 mol%) catalyst loading and good compatibility for both N-H free and N-protected indole substrates. Moreover, it can be used to synthesize carbazoles with various functional groups by a one-pot two-step procedure. The excellent catalytic activity can be attributed to the distinct properties of the supramolecular cage structure in uniformly distributive and well-defined Pd(II) active centers on the cage surfaces.

The assembly of mixed [1,1';3',1'']terphenyl-4,5',4''-tricarboxylic acid (H3TPTC) and [1,1'-biphenyl]-4,4'-dicarboxylic acid (H2BPDC), 2,2'-diamino-[1,1'-biphenyl]-4,4'-dicarboxylic acid (H2BPDC-NH2), or 6-oxo-6,7-dihydro-5H-dibenzo[ d, f][1,3]diazepine-3,9-dicarboxylic acid (H2BPDC-Urea) with Cu2+ ion generated the corresponding copper-paddlewheel-based metal-organic framework (MOF) [Cu5(TPTC)3(BPDC)0.5(H2O)5] (1), [Cu5(TPTC)3(BPDC-NH2)0.5(H2O)5] (1-NH2), or [Cu5(TPTC)3(BPDC-Urea)0.5(H2O)5] (1-Urea). They are isostructural with hierarchical porosity, consisting of zero-dimensional cage (19.2 A × 18.9 A) and one-dimensional pillar channel (29.7 A × 15.1 A) in a manner of face sharing. Platon analyses revealed the porous volume ratios are 80.2%, 80.0%, and 77.8% for 1, 1-NH2, and for 1-Urea, respectively. Thermogravimetric measurements suggested 53, 51, and 48 wt % guest molecules in 1, 1-NH2, and 1-Urea, respectively. 1-NH2 and 1-Urea were precisely functionalized via the introduction of amino and urea functional groups into the pillar channels. The constructed MOF 1-Urea, incorporating both exposed copper active sites and accessible urea functional groups to substrates, presents high efficiency on catalytic CO2 cycloaddition with propene oxide to produce cyclic carbonate in the yield of 98% with a TOF value of 136 h-1 at 1 atm and room temperature. This synergic effect provides a new strategy for designing high-efficient catalysts for CO2 chemical conversion under ambient conditions.

A series of porous MOFs with hendecahedron cage-liked cavity has been constructed from the [Cu2(COO)4] secondary building unit, H3L (H3L = [1,1';3',1'']Terphenyl-4,5',4''-tricarboxylic acid) and pyrazine derivatives varied with different sizes; the structural evolving of the hendecahedron cage and the application in drug delivery and controlled release were presented.

Diastereoselective synthesis of bis-cyclometalated Ir(III) stereoisomers Δ/Λ-[Ir(C∧N)2(d-pro)] and Δ/Λ-[Ir(C∧N)2(l-pro)] (where C∧N is 2-phenylpyridine (Hppy), (4,6-difluorophenyl)pyridine (Hdfppy), and 2-phenylquinoline (Hpq) and pro is proline) with dual stereogenic centers at the metal and auxiliary ligand has been developed. The diastereomers Λ-l and Λ-d, and Δ-l and Δ-d exhibit distinguishable photophysical properties in both solution and the solid state. The thermodynamically stable diastereomers Λ-[Ir(ppy)2(l-pro)], Λ-[Ir(dfppy)2(l-pro)], and Λ-[Ir(pq)2(l-pro)] emit a green emission at 524 nm (Φ = 3.5% and τ = 35 ns), a blue-green emission at 480 nm (Φ = 4.5% and τ = 59 ns), and a red emission at 588 nm (Φ = 6.5% and τ = 200 ns) in DCM solution, respectively, which are blue-shifted accompanied by a large quantum yield and long lifetime relative to the corresponding unstable diastereomers Δ-[Ir(ppy)2(l-pro)] at 537 nm (Φ = 2.3% and τ = 29 ns), Δ-[Ir(dfppy)2(l-pro)] at 489 nm (Φ = 2.8% and τ = 43 ns)...

The Cu3(BTC)2 metal–organic framework (MOF) (BTC = 1,3,5-benzenetricarboxylate), also known as HKUST-1, is one of the earliest reported stable MOFs with a very high surface area. In this study, HKUST-1 was used for the first time to absorb the pharmaceutical products of ibuprofen, anethole and guaiacol with loading amount of 0.34 g·g− 1, 0.38 g·g− 1 and 0.40 g·g− 1, respectively, which also showing good controlled drug release property. The result from this work provides a new attempt for HKUST-1 to be used as potential platform for drug delivery and release.

A novel calcium based metal-organic framework (compound 1) was assembled from the connection of nano-sized {Ca11}SBU (2.36nm) and the triple-connective triangle aromatic acid, to give the formation of 3D MOF of 1 companied with a 2D porous structure with two 1D channel (size: 10.7A×10.8A and 9.4A×8.1A, respectively). The framework of 1 can afford a drug loading content of 0.19g/g of guaiacol and exhibited slow release effect toward guaiacol in 15h in PBS solution.Image 4

Two hexanuclear CoII clusters, NHEt3[Co6(phendc)6 ⊃ X]·MeOH·3H2O (X = Cl− (1) or F− (2)), were obtained accidently by the in situ formation of the coordinating ligand H2phendc (1,10-phenanthroline-...

[Pb2(boa)(Hbbp)2] has been synthesized by treating 4-carboxylphenoxyacetic (H2boa) and 2,6-bis(benzimidazolyl)pyridine (H2bbp) with metal salts under hydrothermal conditions. Adjacent metal centers forms dinuclear metal complex through carboxylato groups as building blocks. The arrangement of the half deprotonated H2bbp ligand and carboxylate groups exhibits a coordination gap around the Pb(II) ion, occupied possibly by a stereoactive lone pair of electrons on Pb(II), with the coordination environment around the lead atoms is hemidirected. This system is a particularly clear example that coordination sphere of a unique dinuclear Pb(II) compound was controlled by lone pair activity, weak Pb···O interactions, π–π stacking and the hydrogen bonds. The above weak interactions influence differently strong red-shifted effect about the solution and solid-state photoluminescence of the compound, compared to the free ligand.

A comparative evaluation of the solvothermal method of synthesis of magnetic Ni(7) discs with four different ligands using the same concentrations of reagents and temperature found microwave heating is more effective than the traditional oven one. Where the former only needs minutes, the latter needs days with an equivalence of 10 min microwave to 1 day of traditional. The size of crystals has a narrow distribution and increases with time for the microwave but is a rather wide distribution for the traditional one. Furthermore the shape of the crystals is more regular for the microwave. The four Ni(7)(II) discs of formulas [Ni(7)L(6)(μ(3)-OMe)(6)](ClO(4))(2) (1-3) and {[Ni(7)(L(4))(6)(μ(3)-OMe)(6)][Ni(L(4))(2)]}(ClO(4))(2) (4) were synthesized as green hexagonal rods from Ni(ClO(4))(2)·6H(2)O in mixed MeOH/MeCN solution and salicylalde Schiff base ligands (L(1) = 2-methoxy-6-(iminomethyl)phenol, L(2) = 2-ethoxy-6-(iminomethyl)phenol, L(3) = 2-methoxy-6-((methylimino)methyl)phenol, L(4) = 2-ethoxy-6-((methylimino)methyl)phenol). X-ray structural analyses show six symmetrically positioned Ni(2) around a central Ni(1) bridged by the μ(3)-methoxide and surrounded by the ligand L which also isolates the discs from one another. The perchlorate sits in the interstices, and the planar [Ni(L(4))(2)] of 4 also inserts itself between the discs. The structures of 1-3 can be regarded as ordered discotic liquid crystals. Electrospray ionization mass spectrometry of solutions showed an exchange of methoxide for hydroxide and a different distribution of [Ni(7)] phase with mixed (MeO/OH) core bridges, confirming a probable "step by step" substitution of MeO(-) by OH(-). Magnetic studies indicate ferromagnetic interaction between Ni(1) and Ni(2) and possible antiferromagnetic between Ni(2) and Ni(2), resulting in a noncollinear system which only reaches half of the moment in 50 kOe at 2 K.