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A new series of luminescent phosphine copper(I) complexes with cyano- and hydroxyl-substituted 2,2′-bipyridine ligands [CuI(bpy(CN)2)(P(PhX)3)2](ClO4) [X = H (1); Me (2); Cl (3)], [CuI(bpy(CN)2)(POP)](ClO4) (4), [CuI(bpy(OH)2)(PPh3)2](ClO4) (5) and [CuI(bpy(OH)2)(POP)](ClO4) (6) have been synthesized and characterized. Three of these complexes have been structurally characterized by using X-ray crystallography. The effect of the attaching –CN and –OH groups at the ortho-positions of bpy ligand was investigated. In CH2Cl2 solution, these complexes show yellow to orange phosphorescence, with the emission maxima not only sensitive to the electronic nature of the bipyridine ligands, but also considerably varied with the modification of phosphine ligands. In addition, these complexes show intense tunable green to yellow emissions in their solid state. To elucidate the electronic structures and transitions of these complexes, density functional theory (DFT) calculations on representative examples revealed that the lowest energy electronic transition associated with these complexes predominantly originates from metal-to-ligand charge transfer transitions (MLCT).

The phase separation behavior of polyoxyethylene sorbitan monolaurate (1.000 mmol/L) was investigated in aqueous micellar solution containing inorganic salt, especially the high concentration of different cationic chlorides including NaCl, KCl, MgCl2, CaCl2, BaCl2 and AlCl3. The continuous decrease in the cloud point (CP) was observed on adding the univalent cationic chlorides (NaCl and KCl). While the addition of multivalent cationic chlorides initially depress the phase separation and then promote the solvation of surfactant in water phase. The relationship between the reciprocal of CP and the concentration of inorganic salt is found to well linearize in the range of a certain concentration of inorganic salt. The dependence of related constant terms in the obtained equations on the nature of inorganic ions was theoretically discussed. The ionic charge vs. atom radium ratio was also used to probe the difference in the effect of different cations on the phase separation. In the framework of phase separation model, the obtained thermodynamic parameters indicate that the process of phase separation is non-spontaneous and the entropy makes an overwhelming contribution.

In aqueous solution at 40 °C, the micellization behavior of the binary mixtures constituted by an amphoteric sodium n-dodecyl diamine sulfonate and a cationic octadecyltrimethyl ammonium bromide has been investigated by the tensiometric technology. The values of critical micelle concentration (cmc) were determined by surface tension measurement of aqueous solution. The experimental data were analyzed according to various mixing thermodynamic models within the framework of the pseudophase separation model. The values of mixed cmc have been predicted successfully by both the Rubingh’s and Rodenas’s treatments. Various parameters like the mixed cmc, interaction parameters between surfactants (β12), the compositions and activity coefficients in mixed micelles as well as thermodynamic properties have been determined using Lang, Rubingh, Rodenas, and Rosen approach. Over the entire composition range investigated, the mixed micelle formation, non-ideal or ideal mixing, and synergistic effect or antagonism are explained by the electrostatic interaction between ionic headgroups of surfactants and the steric effect of surfactant. Thermodynamic parameters favor the process of micellization which is found to be entropy-driven.

The micellization of binary mixtures of sodium dodecyl diamino sulfonate (C12AS) and nonionic octylphenol polyoxyethylene ether (10) (OP-10) was investigated in aqueous solution at a pH of about 6.0. Two techniques, UV–Vis spectroscopy using pyrene as a probe and surface tensiometry, were employed in this work to obtain information on the micellization behavior of the mixed C12AS/OP-10 system. The interaction parameters between the two components, activity coefficients in mixed micelles, compositions of mixed micelles, and thermodynamic parameters of micellization (calculated using Clint’s equation, Rubingh’s treatment based on regular solution theory, and Rodenas’s treatment considering the Gibbs–Duhem equation) were evaluated for this mixed surfactant system. The results show that the synergistic effect between C12AS and OP-10 in all mixed systems plays a vital role in the reduction of the overall critical micelle concentration (cmc) value in aqueous solution. In the process of micellization, both the steric effect of the head group and the charge density for C12AS affect the formation and stability of the mixed micelles, and the entry of a small amount of C12AS into the unconsolidated micelle of OP-10 is more favorable to the formation of the mixed micelle by promoting the reduction of the mixed micelle cmc value. Thermodynamic data show that micellization for the mixed C12AS/OP-10 system is both an enthalpy and entropy driven process.

A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with β-cyclodextrin (β-CD) were oxidized selectively with excellent yields.

A facile, efficient and substrate-selective oxidation of the primary amines with NaClO as oxidant catalyzed by β-cyclodextrin (β-CD) has been developed in water for the first time, and the behavior of β-cyclodextrin that catalyzed the primary amines to nitriles in water was investigated. It was found that the primary amines which could form host-guest complexes with β-cyclodextrin were oxidized to nitriles with excellent yields at ambient temperature. The results show that β-cyclodextrin worked not only as a solubilizing agent but also as a catalyst in these reactions.

A novel ultraviolet absorption spectrometry method was developed for the quantitative determination of HABS by adding β-cyclodextrin with the molar ratio of 1:1 in strong interference aqueous solution. The results indicated that the effect of several common interfering flooding agents (SAS, OP-10, HPAM) on the determination of HABS could be greatly reduced in β- cyclodextrin aqueous solution. Thus, the determination errors of the determined HABS were less than 2.0% under strong inter- ference, and the detection limit (S/N==3) of the method could be also as high was 8.3-9.1 x 10(-4) mg · L(-1). Various characterization results including 1H-NMR, TG-DSC and FTIR showed the interaction between β-cyclodextrin and HABS. The results of H-NMR analysis showed that HABS molecule could enter into the interior of the cavity of β-cyclodextrin molecule. TG-DSC analysis exhibited that the stable inclusion of β-cyclodextrin and HABS could be automatically formed. The interactions between the functional groups of β-cyclodextrin and HABS were showed by FTIR analysis, which also exhibited that the stable inclusion could be formed by HABS entering from the narrow or the broad mouth of the β-cyclodextrin. The interference of the UV spectrum of HABS could be reduced by β-cyclodextrin since the interaction between β-cyclodextrin due to the interaction between β-cyclodextrin and HABS in the inclusion complex.

A facile, substrate-selective and transition metal-free oxidation of benzylic and allylic alcohols catalyzed by β-cyclodextrin with NaOCl oxidant using water as an only solvent was developed.

A novel enhanced ultraviolet absorption spectrometry method was developed for the quantitative analysis of SDBS induced by beta-cyclodextrin(beta-CD) with strong interferences. The ultraviolet absorption spectra of SDBS indicated that the presence of beta-CD could result in the enhancement of absorption intensities of SDBS. A good linearity was obtained between the UV-absorption intensity of the system and the concentration of SDBS. The results indicated that the determination precision and the determination ranges of SDBS could be greatly improved by beta-CD. The effect of several common interfering substances (SDS, OP-10, HPAM) on the determination of SDBS could be significantly reduced in beta-CD aqueous solution. Therefore, the maximum errors of the determined SDBS were less than 2.0% under multifactor interferences, and the precision of the method was also as high as 10(-2) - 10(-3) mg x L(-1). The stable inclusion of beta-CD and SDBS could be automatically formed in water with molar ratio of 1 : 1. The stability constant of the inclusion, K(a), was 87 and the standard Gibbs function of molar reaction, delta(gamma)G(m)(see symbol) (298 K), was -11.064 kJ x mol(-1). FTIR analysis exhibited that SDBS could be induced by beta-CD since the phenyl group in SDBS molecule could exist stably in the cavity of beta-CD and form the inclusion.

A facile, efficient and substrate-selective oxidation of aldehydes to carboxylic acids with NaClO catalyzed by β-cyclodextrin in water has been developed. A series of aldehydes which could form inclusion complex with β-cyclodextrin (β-CD) were oxidized selectively with excellent yields.

A facile, substrate-selective and transition metal-free oxidation of benzylic and allylic alcohols catalyzed by β-cyclodextrin with NaOCl oxidant using water as an only solvent was developed.