Macroporous polymer supported nanoparticles of copper(I) iodide catalyst and macroporous polymer supported azide reagent were used to simplify the synthesis of 1,4-disubstituted-1H-1,2,3-triazoles from various benzyl halides following the green chemistry principles. This new one-pot protocol facilitates the workup of the reaction and provides the products in short times and at high yields. Heterogeneous catalyst and reagent can be reloaded and reused at least for 5 runs without significant decrease in the yields.Electronic supplementary materialThe online version of this article (doi:10.1186/2193-1801-2-64) contains supplementary material, which is available to authorized users.

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L-prolinate anion immobilized onto amberlite IRA900OH ([Amb]L-Prolinate) is reported as a new, reusable and cheap organocatalyst for the condensation of indoles with isatins to afford the corresponding 3,3¢-diaryloxindol derivatives in ethanol under reflux condition.[Amb]L-Prolinate was achieved by the treatment of a MeOH/H 2 O solution of L-proline with amberlite IRA900OH at 60°C. The procedure for heterogenization of L-proline organocatalyst is based on non-covalent ion-pair immobilization of L-proline on the surface of anion-exchange resin amberlite IRA900OH (AmbIRA900OH) as a commercially accessible cationic polymer support. The prepared heterogeneous organocatalyst was well characterized by using of FTIR, TGA, DTG, XRD and elemental analysis techniques. The catalytic activity of the catalyst was also examined in the reaction of indole and isatin. The catalyst has been recovered and its reusability confirmed in 8 runs.

This research aimed at evaluating the stability of the 2-halo-1,3,2dioxaphosphinanes conformers at the LC-BLYP/aug-cc-pVTZ level of theory. The estimation of the total energy and the dipole moments of the axial and equatorial conformations were first done for the aforementioned molecules. Intermediate states of the transformations of the axial to equatorial conformer were determined. In the basis of the calculations, the axial conformer was found to be more stable than the equatorial conformer in these molecules. Transition states of these transformations were studied, as well. IN addition, the energetic and thermodynamics parameters of these transformations were investigated. Change of the P=O bond distances were illustrated with endo and exo-anomeric effects. The comparison of the P-O bond distances indicated the shorter bonds in the axial conformer compared to the equatorial conformer. These changes attributed to a dominant LP (2)O  σ* (P-X) negative hyperconjugation interaction between a pair of non-bonded electrons on oxygen and the adjacent P-X bond in axial conformer. The partitioning of the total electronic energy E(tot) into Lewis E(L) and non-Lewis E(NL) parts was performed using the concept of the natural bond orbital (NBO) analysis. Then, the natural coulomb electrostatic (NCE) potential energies, total energies into Lewis components, and total steric exchange energies were estimated. Calculations revealed that axial conformer was more stable than the equatorial conformer in the studied molecules. In addition, the barrier energy values of the transformations of axialboatequatorial conformers enhanced with decreasing the electronegativity of halogen. KEYWORDS 2-Halo-1,3,2-dioxaphosphinanes Anomeric effect Conformers Natural bond orbital analysis

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