Constructing chiral polyoxometalate assemblies via supramolecular approaches

Polyoxometalates (POMs), as a typical class of discrete metal oxide clusters that are known in inorganic and structural chemistry since long, have displayed more and more interesting applications over recent years. However, in comparison to the chemical synthesis, the photochemical, electrochemical, and magnetic properties, the structural asymmetry, and relative characteristic investigations arising therefrom are far behind even if they are very important for functional materials, especially in solution systems. One of the main reasons is that it is hard to control and maintain a stable chiral state of POMs to carry out further corresponding performances. Aiming to overcome these disadvantages, the main concerns of this review are to discuss the generation of the chirality for discrete metal oxide clusters, chirality transfer via a supramolecular approach, chirality amplification in self-assemblies, and the related functional properties such as photochromism, catalysis, and bioactivities in solutions. Considering that some previous reviews dealt with chiral structures and packing architectures in the crystalline solids of POMs, this article only concentrates on the induced chirality and material properties in solution systems, which have been more active recently but no review article has been involved in this interesting area.

A HPLC-ICP-AES technique for the screening of [XW11NbO40]n− aqueous solutions

In this research combined HPLC-ICP-AES technique was used to study formation of mixed [XW₁₁O₄₀]ⁿ⁻ (X = P, Ge, B) complexes.

Chiral polyoxomolybdate-based hybrid compounds obtained by spontaneous resolution: syntheses, structures and non-linear optical properties

By spontaneous resolution, two chiral hybrid 2D architectures [MMo₆O₂₁(glycine)₃]²⁻ (M = Te 1, Se 2) were obtained, which show an SHG efficiency of about 3.5 and 3.7 × KDP.

Temperature-induced racemic compounds and chiral conglomerates based on polyoxometalates and lanthanides: syntheses, structures and catalytic properties

Four new species, originated from [Co₂Mo₁₀H₄O₃₈]⁶⁻ and lanthanides by adjusting the reaction temperature, are reported, which act as Lewis acid–base catalysts toward the cyanosilylation reaction.

Synthesis and characterization of organotriphosphonate-functionalized TM-containing polyoxotungstates

A new family of organotriphosphonate-functionalized TM-containing polyoxotungstates, K₄H₆[H₄{(AsW₉O₃₃)TM(H₂O)W₅O₁₁(N(CH₂PO₃)₃)}₂(μ₂-O)₂]·24H₂O [TM = Ni (1), Co (2), Mn (3)], have been synthesized from the preformed POM precursor [As₂W₁₉O₆₇(H₂O)]¹⁴⁻.

A series of polyoxometalate-based compounds including infinite Ag belts and circles constructed by two tolyl-1H-tetrazole isomers

Three novel Keggin-based complexes constructed by two new isomeric ligands 5-o-tolyl-1H-tetrazole and 5-m-tolyl-1H-tetrazole have been synthesized under hydrothermal conditions via changing the types of POM anions and organic ligands.

Strong intermolecular exciton couplings in solid-state circular dichroism of aryl benzyl sulfoxides

A series of 13 enantiopure aryl benzyl sulfoxides () with different substituents on the two aromatic rings has been previously analyzed by means of electronic circular dichroism (CD) spectroscopy. Most of these compounds are crystalline and their X-ray structure is established. For almost one-half of the series, CD spectra measured in the solid state were quite different from those in acetonitrile solution. We demonstrate that the difference is due to strong exciton couplings between molecules packed closely together in the crystal. The computational approach consists of time-dependent density functional theory (TDDFT) calculations run on "dimers" composed of nearest neighbors found in the lattice. Solid-state CD spectra are well reproduced by the average of all possible pairwise terms. The relation between the crystal space group and conformation, and the appearance of solid-state CD spectra, is also discussed.