Comparative study of the vicinal functionalization of olefins with 2:1 bromide/bromate and iodide/iodate reagents
作者:Manoj K. Agrawal、Subbarayappa Adimurthy、Bishwajit Ganguly、Pushpito K. Ghosh
DOI:10.1016/j.tet.2009.01.095
日期:2009.4
halohydrins, halo methyl ethers, and halo acetates from olefins using 2:1 Br−/BrO3− and I−/IO3− reagents. In many cases both reagents afforded products selectively in high yields. The highest halogen atom efficiencies attained were 97% and 93% for Br−/BrO3− and I−/IO3−, respectively. Of the two reagents, I−/IO3− was established to be the preferred reagent for vicinal functionalization of linear alkenes and
ABSTRACT A simple, efficient, and environmentally benign protocol for the synthesis of vicinal iodohydrins and iodoesters from olefins using NH4I and Oxone in CH3CN/H2O (1:1) and dimethylformamide (DMF) / dimethylacetamide (DMA), respectively, without employing a catalyst at room temperature is described. Regio- and stereoselective iodohydroxylation and iodoesterification of various olefins with anti fashion
Aerobic Oxidation of Alkenes to Esters of Vicinal Diols with a<i>syn</i>-Configuration Catalyzed by I<sub>2</sub>and the H<sub>5</sub>PV<sub>2</sub>Mo<sub>10</sub>O<sub>40</sub>Polyoxometalate
作者:Ronny Neumann、Olena Branytska
DOI:10.1055/s-2005-917069
日期:——
A new method for the synthesis of vicinal diols fromalkenes has been developed. Reaction of molecular iodine in the presence of a polyoxometalate as oxidation catalyst under aerobic conditions in acetic acid solvent leads to the oxidative iodoacetoxylation of an alkene, i.e. formation of a 1,2-iodoacetate. Further in situ substitution of the iodide by water yields the 1,2-diol monoacetate with a predominantly
Triiodoisocyanuric acid: a new and convenient reagent for regioselective coiodination of alkenes and enolethers with oxygenated nucleophiles
作者:Rodrigo da S. Ribeiro、Pierre M. Esteves、Marcio C.S. de Mattos
DOI:10.1016/j.tetlet.2007.10.011
日期:2007.12
The reaction of triiodoisocyanuric acid (prepared from I2 and trichloroisocyanuric acid in 90% yield) with alkenes in the presence of oxygenated nucleophilic solvents (alcohols, AcOH and H2O) led to the corresponding β-iodoethers, β-iodoacetates and iodohydrins, in 66–98% isolated yield. Enolethers reacted with triiodoisocyanuric acid in MeOH to produce dialkylacetals (70–83%).
I<sup>−</sup>/IO<sub>3</sub><sup>−</sup>Assemblies as Promoters of Iodohydrin Formation
作者:Subbarayappa Adimurthy、Gadde Ramachandraiah、Pushpito K. Ghosh
DOI:10.1080/00397910701239031
日期:2007.5
Abstract The direct conversion of olefins to their corresponding iodohydrins is efficient with I−/IO3 − assemblies in an aqueous acidic medium. Iodohydrins were obtained in moderately good yields at ambient reaction conditions without employing any metal catalysts. The addition of IOH across the olefin follows the Morkovnikov's rule.