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The aluminum(III) triflate catalyzed three-component coupling reaction of alkynes, amines and phosphorylated aryl aldehydes to access phosphoryl quinoline derivatives has been developed. The reaction proceeds in a simple system without the use of transition metals, ligands or additives, thus making it attractive for the fast preparation of a variety of new potential N-P bidentate ligands.

Two reduced Schiff bases, namely 5-[(2-hydroxybenzyl)amino]isophthalic acid (1) and 5-[(pyridin-4-ylmethyl)amino]isophthalic acid (2), were synthesized in two-step method using 5-aminoisophthalic acid as the starting material, and were characterized by single-crystal X-ray diffraction, elemental analysis, infrared, 1H NMR, mass, absorption and fluorescence spectra. Both 1 and 2 crystallize in monoclinic system with space groups P21/c for 1 and P21/n for 2. Photophysical properties of both 1 and 2 are significantly different from those of raw material 5-aminoisophthalic acid due to stronger p → π conjugation when one amino hydrogen atom in 5-aminoisophthalic acid is substituted with electron-donor group. 1 displays a very strong narrow-band blue fluorescence with the maximum peak at 439 nm, a high quantum efficiency up to 64%, and a narrow full width at half maximum of 35 nm, while 2 has a broader and weaker fluorescence with the peak at 418 nm and FHWM of about 50 nm. Two reduced Schiff bases with blue fluorescence were synthesized from 5-aminoisophthalic acid in two-step method including formation of the corresponding Schiff bases and further reduction by NaBH4.

The solvothermal assembly of Co(OAc)2·4H2O with 5-fluoro-2-hydroxy-benzoic acid (H2fhba) and 1,10-Phenanthroline (phen) yielded a new linear trinuclear cobalt cluster, [Co3(Hfhba)2(phen)2 (μ 2-OAc)4] (1). The complex 1 was characterized by IR spectroscopy, elemental analysis and X-ray single-crystal diffraction. The study of magnetic properties indicates that antiferromagnetic coupling interactions exist between the adjacent Co(II) ions. So the 5-fluoro-2-hydroxy-benzoic acid participates in transferring magnetic interaction for the first time.

ZnSe:Mn and core–shell ZnSe:Mn/ZnS doped quantum dots (d-dots) have been synthesized by using the alkylamine–H2Se complex and thiourea as new phosphine-free Se and S precursors, respectively. Absorption spectroscopy, steady-state (solution and solid-state) and time-resolved photoluminescence spectroscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy were used to characterize the resulting d-dots. Results showed that Mn2+ was successfully doped and mainly distributed in the middle layer of the actual ZnSe/ZnSe:Mn/ZnSe d-dots and ZnSe/ZnSeS:Mn/ZnS d-dots which were simply referred to as ZnSe:Mn and core–shell ZnSe:Mn/ZnS d-dots with ZnSe and ZnS outmost shells, respectively. The increase in the intensity of phosphorescence from the dopant Mn2+ was obtained by the corresponding injection of Zn precursor or Zn/S precursors for ZnSe or ZnS shell growth. As compared to the ZnSe shell, the ZnS shell was grown more significantly on the surface of the ZnSe:Mn core, which led to larger d-dots due to a thicker ZnS shell and thus deeper doping of Mn2+ in the larger host. Outstanding improvement has been achieved in both phosphorescence intensity and stability after growth of the ZnS shell relative to the ZnSe shell. The corresponding phosphorescence efficiency of the resulting d-dot cyclohexane solution was enhanced from about 8% for the ZnSe:Mn d-dots to 35% for the ZnSe:Mn/ZnS d-dots.

Zinc selenide (ZnSe) nanocrystals were synthesized via a phosphine-free route using the highly reactive alkylamine-H2Se complex as selenium precursor and zinc precursors with different reactivity. The reactivity of zinc precursor was tuned by using three kinds of zinc carboxylates with different alkyl chain lengths, including zinc acetate, zinc nonanoate, and zinc stearate. The effect of the reactivity and the amount of zinc precursor on nucleation and growth of ZnSe nanocrystals were investigated by ultraviolet-visible absorption and photoluminescence spectra. Result indicates that the growth and optical property of the resulting ZnSe nanocrystals are strongly dependent on the alkyl chain length and the amount of the zinc carboxylates and both shorter alkyl chain length, and more amount of zinc carboxylate will lead to faster growth of ZnSe nanocrystals. This allows that the controlled growth and excellent optical property of high-quality ZnSe nanocrystals can be achieved by combining the different reactivity and the used amount of zinc precursor, such as by using stoichiometric and reactive Zn precursor and Se precursor or by using larger amount of more unreactive Zn precursor relative to the highly reactive alkylamine-H2Se complex precursor.

The reaction of Ni(ClO4)2·6H2O with a dilithium 2-[(2-hydroxy-3-ethoxy-enzylidene)-amino]-ethane sulfonic acid (Li2L) in a acetonitrile solution under solvothermal conditions leads to the formation of heterometallic tetranuclear cubane cluster [Ni3Li(L)3(OH)(CH3CN)3]·0.5CH3CN (1, where Li2L = dilithium 2-[(2-hydroxy-3-ethoxy-benzylidene)-amino]-ethanesulfonate). Complex 1 displays dominant ferromagnetic interactions through μ3-O (oxidophenyl and hydroxyl) binding modes.

The title quantum dots are prepared at 240 °C using Zn(OOC-(CH2)7-Me)2 and Mn(OOC-(CH2)7-Me)2 as Zn and Mn precursors, respectively.

The asymmetric unit of the title compound, [CdCl2(C7H10N2O2S)2], contains two complex molecules with similar configurations. The CdII atoms are each six-coordinated by two thiazole N and two carbonyl O atoms from the 2-(2-amino-1,3-thiazol-4-yl)acetate ligand, and by two Cl− anions in a distorted octahedral geometry. In the crystal, intra- and intermolecular N—H...Cl hydrogen bonds create parallel chains along [1-10]. C—H...Cl interactions also occur.

In the title compound, [Ni(C(7)H(3)Cl(2)O(2))(2)(C(3)H(7)NO)(H(2)O)], the Ni(II) ion is coordinated by four O atoms from two bidentate 2,4-dichloro-6-formyl-phenolate ligands, one O atom from a water ligand and one O atom from a dimethyl-formamide ligand in a slightly distorted octa-hedral environment. In the crystal structure, centrosymmetric dimers are formed though O-H⋯O and O-H⋯Cl hydrogen bonds; π-π stacking inter-actions, with a centroid-centroid distance of 3.796 (2) Å, are also found.