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A stable and isolable bis[(tetrabutylammonium) di-μ-iodo-diiododicuprate(i)] complex has been identified for the direct oxidative synthesis of α-ketoamides from substituted aryl methyl ketones and secondary amines in the presence of molecular oxygen. Gratifyingly, this Cu(i) complex acts as an effective catalytic system with enhanced solubility in both water and organic solvents. These reactions were effectively accelerated by microwave irradiation in water and were applied for the synthesis of a variety of substituted α-ketoamides with good yields. It was interesting to note that, in these optimized microwave reaction times, α-ketoamides were the exclusive products and amide byproducts observed in previous reports were not formed. [ABSTRACT FROM AUTHOR]

Traditional organic chemistry, and organic synthesis in particular, relies heavily on organic solvents, as most reactions involve organic substrates and catalysts that tend to be water-insoluble. Unfortunately, organic solvents make up most of the organic waste created by the chemical enterprise, whether from academic, industrial, or governmental labs. One alternative to organic solvents follows the lead of Nature: water. To circumvent the solubility issues, newly engineered "designer" surfactants offer an opportunity to efficiently enable many of the commonly used transition metal-catalyzed and related reactions in organic synthesis to be run in water, and usually at ambient temperatures. This review focuses on recent progress in this area, where such amphiphiles spontaneously self-aggregate in water. The resulting micellar arrays serve as nanoreactors, obviating organic solvents as the reaction medium, while maximizing environmental benefits. [ABSTRACT FROM AUTHOR]

The high crystallization degree of chitosan and therefore its poor solubility in water and in most of the conventional organic solvents limits its extensive applications in practical processes. In this study, ionic liquids [C4mim][HCOO], [C4mim][CH3COO], [C4mim][CH3CH2COO], [C4mim][CH3CH2CH2COO], [C4mim][HOCH2COO], [C4mim][C6H5COO], [C4mim][CH3CHOHCOO] and [C4mim][N(CN)2] have been used to study the effect of anionic structure on solubility of chitosan and the possible dissolution mechanism in ionic liquids. For this purpose, solubilities of chitosan in these ionic liquids have been determined as a function of temperature, and hydrogen bond accepting ability of the ionic liquids has been estimated by 1H NMR and solvatochromic UV/vis measurements. At the same time, the interaction between [C4mim][CH3COO] and chitosan in the chitosan + [C4mim][CH3COO] solution is investigated by 13C NMR, and the regenerated chitosan from ionic liquids by addition of ethanol is characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). It is shown that in the ionic liquids investigated, [C4mim][CH3COO] is the most efficient ionic liquid for the dissolution of chitosan. Solubilities of chitosan increase almost linearly with increasing hydrogen bond accepting ability of the ILs. Both the anions and the [C4mim]+cation play important roles in the dissolution of chitosan, possibly by the disruption of native hydrogen bonds in chitosan. In addition, good thermal stability has been observed for the regenerated chitosan. [ABSTRACT FROM AUTHOR]