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Circular dichroism spectra of the self-assembled porphyrins which showed intense Cotton effects are mirror-images for the two 31-enantiomers and proved that the supramolecular chirality is dependent on the configuration at the 31-stereocenter. Friedel-Crafts conditions at short reaction times with high concentrations of catalyst and at 0-4 degree [Celsius] was used to perform diacylation of copper 10, 20-bis(3,5-di-tert-butylphenylporphyrin) to obtain 3,17-diacyl-substituted porphyrins, out of the 12 possible regioisomers.

The hydrothermal conditions from aqueous solutions of lanthanide(III) bromides, CB[6], and 4-cyanopyridine were employed to synthesize the sandwich-type tetranuclear lanthanide complexes with cucurbit[6]uril. The chainlike crystal structure of polymers (Ln = La, Pr, and Dy) are constituted by the sandwich complexes linked via the coordination of IN nitrogen atoms to the silver atoms and could be used as precursors for the synthesis of lanthanide-silver heterometallic coordination polymers.

The syntheses, molecular and crystal structures, and electrochemical properties of three new inclusion compounds derived from cobalt(III) and nickel(II) complexes with 1,3-diaminopropane (tn) or 1,3-diamino-2-propanol (tmOH) and the macrocyclic host cucurbit[8]uril is reported. The results showed that the encapsulation of trans-[[Co[(tn).sub.2][Cl.sub.2]].sup.+] within the cavity of CB[8] stabilizes the complex toward ligand substitution reaction in aqueous solution.

The synthesis and characterization of the gold cluster compound [[Au.sub.18][(P).sub.2][(PPh).sub.4](PHPh)[(dppm).sub.6]][Cl.sub.3] (where dppm = [Ph.sub.2]PC[H.sub.2]PP[h.sub.2]) which shows a central [Au.sub.7[P.sub.2] unit formed by two P centered gold tetrahedra sharing the central gold corner is presented.

The synthesis and characterization of five new selenometallic clusters, (argentoselenometalatic compounds) containing univalent silver (I) ion and phosphine ligands are presented. The fact that the properties of the presented metal clusters can be finetuned by altering the constituent elements and skeleton structures make them promising candidates of optical limiting materials among all the selenometallic clusters studied to date.

The binary materials ZnS, ZnSe, and ZnTe are prepared within the mesoporous framework of MCM-41 at room temperature through the use of silylated chalogen reagents. The ZnE-MCM-41 materials are characterized and the observed blue shift in the absorption maximum has agreed well with the expected quantum confinement of these materials given the nanometer dimensions of the mesoporous architecture of the silicate host.

Isocyanides are important ligands in coordination chemistry as they bind on gold and other metals. An investigation of the coordination behavior of 1,1'-diisocyanoferrocene toward gold (I) leads to an unprecedented diauraferrocenophane.

[Pb{Mn(CO)5}3][AlCl4] containing a trigonal planar PbMn3 cluster was obtained by the reaction of PbCl2 and Mn2(CO)10 in the ionic liquid [BMIm][AlCl4]. The title compound is composed of [Pb{Mn(CO)5}3]+ carbonyl cations and [AlCl4]− anions that are connected to infinite zig-zag chains. The [Pb{Mn(CO)5}3]+ cation exhibits a central PbMn3 cluster with three equal Pb–Mn single bonds, resulting in an almost equilateral triangle of three manganese atoms with a formal Pb+I in its center. Such a cluster and compound were identified for the first time. In addition to single-crystal structure analysis, the composition, structure and properties were further characterized by density functional theory (DFT) calculations, energy dispersive X-ray spectroscopy (EDXS), and Fourier-transform infrared spectroscopy (FT-IR), as well as optical spectroscopy (UV-Vis). [ABSTRACT FROM AUTHOR]

A study that focuses on the design of metal sulfide catalysts is presented. In this study, nitrogenase is taken as a model and the problems encountered are recounted.

The reaction of the bis(dichlorogold) complex of 2,3-bis(diphenylphosphino)maleic anhydride (L1) with S(SiMe3)2 in the presence of NaBPh4 yields the ionic dodecanuclear cluster compound [Au12(PPh2)2S4(L2)4](BPh4)2 (1). During the formation of 1, the initial ligand L1 is transformed into the doubly sylilated derivative, 3,4-bis(diphenylphosphino)-2,5-bis(trimethylsilyloxy)-furan (L2). The presence of bridging PPh2 groups is a result of the transformation of L1 in the coordination sphere of Au(i). Compound 1 was characterized by single crystal X-ray diffraction and electrospray-ionization (ESI) mass spectrometry. [ABSTRACT FROM AUTHOR]

A 3D porous perchlorinated metal-organic framework (MOF), LIFM-26, featuring dual functionality, that is, functional polar groups and open metal sites, has been synthesized using perchlorinated linear dicarboxylate to link trigonal prismatic Fe3(μ3-O) units. LIFM-26 exhibits good thermal and chemical stability, and possesses high porosity with a BET surface area of 1513 m2 g−1, compared with isoreticular MOF-235 and Fe3O(F4BDC)3(H2O)3 (F4BDC=2,3,5,6-tetrafluorobenzene-1,4-dicarboxylate). Most strikingly, LIFM-26 features good gas sorption/separation performance at 298 K and 1 atm with IAST selectivity values reaching up to 36, 93, 23, 11, 46, and 202 for CO2/CH4, CO2/N2, C2H4/CH4, C2H6/CH4, C3H8/CH4, and R22/N2 (R22=CHClF2), respectively, showing potential for use in biogas/natural gas purification and CO2/R22 capture. [ABSTRACT FROM AUTHOR]

Two analogous M4L4-type tetrahedral cages (smaller: MOC-19; larger: MOC-22) were synthesized and investigated for their interactions with the anticancer drug 5-fluoracil (5-FU) by NMR spectroscopy, high-resolution electrospray-ionization mass spectrometry (HR-ESI-MS), and molecular simulation. The cage's size and window are of importance for the host-guest binding, and consequently the smaller MOC-19 with a more suitable size of cavity window was found to have much stronger hydrogen-bond interactions with 5-FU. The porous nanoparticles of MOC-19 exhibited outstanding behavior for the controlled release of 5-FU in a simulated human body with liquid phosphate-buffered saline solution. [ABSTRACT FROM AUTHOR]

Fluoroarylimine-stabilized iron(II) hydrides were used for the activation of CO2. The resulting iron(II) formate complex 6, which was obtained by formal CO2 insertion into the Fe-H bond, turned out to be unstable in solution. CO was suitable for the formation of stable analogues of complex 6. From the three-component reaction of CO, CO2, and iron hydride, a series of stable carbonyl formate iron(II) complexes 7- 9 were generated. Iron(II) formate complex 6 could also be obtained from the reaction of the iron(II) hydride complex with formic acid. On the basis of this result, the dehydrogenation of formic acid catalyzed by iron(II) hydrides was explored. The reaction was monitored by in situ 1H NMR spectroscopy, and a possible mechanism was proposed. In addition, iron(II) hydrides also reacted with CS2 to generate thiocarboxy iron(II) complexes 12, 13, 14, and 16. Unexpected complex 17 was produced from the three-component reaction of CS2, complex 4, and compound 15. The possible mechanism of the three-component reaction was also studied by operando IR spectroscopy. [ABSTRACT FROM AUTHOR]