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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.

A convenient and practical procedure to prepare Pd(II) metallogel as a highly efficient and recyclable catalyst for Suzuki-Miyaura coupling has been developed. Such metallogel shows highly processable and reversible responses to thermal and mechanical stimuli. The xerogel is a highly efficient (0.005 mol% Pd) heterogeneous catalyst for Suzuki-Miyaura couplings with arylhalides and phenylboronic acids in excellent yield in water or ethanol under ambient atmosphere. The reaction could be scaled up to 10 gram scale with 0.001 mol% Pd catalyst loading with 99% yield. The catalyst can be recycled and reused at least seven times without loss of activity.

Nonlocal density functional theory [DFT] has been used to compute vibrational frequencies and intensities of nickel porphine and of several isotopomers via a scaled quantum mechanical [SQM] force field [FF]. The results support and extend those obtained from a revised empirical FF. The force constants are similar for the two FF's, although the SQM FF has a complete set of off-diagonal elements. The SQM FF produces somewhat more accurate frequencies and isotope shifts than the empirical FF for the in-plane NiP modes. In addition, the SQM FF calculates out-of-plane modes that are in good agreement with available infrared [IR] data. Also, the SQM FF satisfactorily reproduces the relative intensities of both IR and [off-resonance] Raman bands. A striking result is the calculation of large Raman intensities for nontotally symmetric B1g modes, in conformity with experimental FT-Raman spectra. This effect is attributed to the phasing of local polarizability components of the pyrrole rings and methine bonds. The ...

The gauge including atomic orbital (GIAO) method at the self-consistent field (SCF) level of theory was used to calculate magnetic shielding tensors in free base porphyrin (H2P) and in magnesium (MgP) and zinc (ZnP) metalloporphyrins, as well as in the MgP(H2O) and MgP(H2O)2 complexes. All principal components of the calculated shielding tensors are reported. We have recorded new solution NMR spectra for all three molecules under identical conditions, to ensure the reliability of small differences in their NMR shifts. The calculated isotropic values are compared with these values and with low-temperature solid-state shifts, which resolve the tautomerism in H2P. Agreement with experiment is good. It is encouraging that the calculations correctly reproduce most of the the small differences in the chemical shifts. A comparison of the observed and calculated NMR shifts of MgP leads to the conclusion that the species observed in tetrahydrofuran solution is either MgP(H2O)2 or MgP(THF)2. We have calculated the ...

The title compound, [Zn(C15H13N2O)Cl(C15H14N2O)], has a mononuclear structure, in which the central zinc ion is coordinated by two benz­imidazole N atoms, one phenolate O atom and a chloride ion in a distorted tetrahedral arrangement. In the crystal structure, there are intramolecular π–π stacking interactions between the phenol and benz­imidazole ring systems; intermolecular π–π stacking interactions between the benz­imidazole ring systems of adjacent mol­ecules are also present. A strong intermolecular O—H⋯O hydrogen bond is also observed.

The title compound, [Mn(C6H2O4S)(C10H8N2)(H2O)3]·0.5C10H8N2·3H2O or [Mn(tdc)(bpy)(H2O)3]·3H2O·0.5(bpyn) (tdc is thio­phene-2,5-di­carboxyl­ate, bpy is 2,2′-bi­pyridine and bpyn is 4,4′-bi­pyridine), crystallizes in space group P\overline 1. Complex molecules are linked into one-dimensional chains, running along the b axis, by hydrogen bonds between the coordinated aqua ligands and uncoordinated carboxyl­ate groups of tdc. Double-stranded chains consist of two of the one-dimensional chains and uncoordinated centrosymmetric bpyn mol­ecules, connected by hydrogen bonds between N atoms of the bpyn mol­ecules and coordinated aqua ligands. These double chains are further assembled into layers parallel to the ab plane, which extend into three-dimensional networks via hydrogen bonds between the coordinated and uncoordinated water molecules, and O atoms of tdc.

In the crystal structure of the title complex, C10H8N2·C6H4O4S or bpy·tdc (bpy is 4,4′-bi­pyridine and tdc is thio­phene-2,5-di­carboxyl­ic acid), bpy and tdc form one-dimensional zigzag chains as a result of O—H⋯N hydrogen bonds. These chains are further assembled into layers by van der Waals attractions, which are extended into a three-dimensional network by van der Waals and aromatic π–π stacking interactions.

In the crystal structure of the title compound, [Ag2(N3)2(C2H8N2)], the Ag atoms of adjacent polymeric AgN3 chains are bridged by the 1,2-di­amino­ethane ligand to furnish a ribbon structure. The Ag atom shows trigonal planar coordination. The 1,2-di­amino­ethane ligand lies on an inversion center.

A stable nanocomposite metallogel was obtained by the addition of [Na(L)(H2O)]·2H2O (HL = 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol) to an aqueous solution of Cu2(OAc)4·2H2O in a molar ratio of Cu/L = 4 (5.6 wt% gelator concentration), from which 1D coordination polymers [Cu2L(μ-OAc)2(μ-OH)] (1) and coordination nanoclusters {[Cu9L4(OAc)7(OH)5]2+}2 (3) were afforded. The nanoclusters 3 stabilize the 1D coordination polymers 1 and inhibit crystallization of 1 from the system, generating a coordination-based heat-set nanocomposite hydrogel at room and higher temperatures that flows upon cooling to 4 °C, in sharp contrast to most supramolecular gels. Reversible thermo and pH responsive solution–gel phase transitions were observed. The results described herein may open a novel avenue for functional coordination nanocomposite materials.