2435-37-2Relevant academic research and scientific papers
Hydrogen-free homogeneous catalytic reduction of olefins in aqueous solutions
Gaviglio, Carina,Doctorovich, Fabio
, p. 5379 - 5384 (2008/12/20)
(Chemical Equation Presented) Herein we report a study involving the homogeneous catalytic reduction of unsaturated substrates in aqueous solutions or water-organic solvent mixtures. The reduction of olefins has been carried out in the presence of catalytic amounts of [Fe(CN)5NH3] 3- and excess of NH2OH, which under mild reaction conditions can be used to reduce carbon-carbon unsaturations without affecting carbonyl functionalities and aromatic rings. To explore the scope of the catalytic reduction, a wide variety of representative unsaturated substrates have been examined. The steric effects of the substituents on the carbon-carbon multiple bond as well as the regioselectivity and stereoselectivity of the catalyst have been studied. The deuterium kinetic isotope effect on the catalytic reduction of double bonds in olefins has been analyzed, and no significant kinetic isotope effect was found. Among the great advantages of this novel procedure for catalytic reduction are that hydrogen and high pressures are not needed, the catalyst is inexpensive and easily prepared, and water as well as water-organic solvent mixtures can be used as reaction media.
Optical Resolution of trans-Bicycloheptane-2,3-diamine: Chiral Recognition in the Crystal of its Complex with (2R,3R)-O,O'-Dibenzoyltartaric Acid
Hatano, Keiichiro,Takeda, Tadahiro,Saito, Reiko
, p. 579 - 584 (2007/10/02)
The synthesis of trans-bicycloheptane-2,3-diamine (6c), its optical resolution via formation of its complex with (2R,3R)-O,O'-dibenzoyltartaric acid (-BTA), and the crystal structure determination of this complex by X-ray diffraction techniques are reported.The absolute configuration of 6c in the complex has been determined to be (S,S)-6c from the endowed chirality of -BTA, thus optical resolution of 6c is achieved.Crystal data for the (S,S)-6c*(-BTA) complex is reported: C25H28N2O8*2H2O, M = 520.54, monoclinic P21, a = 9.150(1), b = 8.581(1), c = 17.036(1) Angstroem, β = 103,30(1) deg, V = 1301(2) Angstroem3, Z = 2, R = 0.037.The crystal of the molecular complex is found to have a multilamellar structure partitioned by thin hydrogen bonded sheets containing complex ammonium-carboxylate-water hydrogen bonds.Attached on both sides of the sheet, monolayer templates with benzoyl groups of -BTA and bicycloheptane fragments of 6c stack with the next templates to form hydrophobic bilayers.In the monolayer template, a cavity is formed surrounded by two pairs of two benzoyl groups distinguished from each other by their orientations toward the hydrogen bond sheet.The cavity provides a final site for the chiral recognition of 6c.The (S,S)-enantiomer of 6c is probably distinguished from the (R,R)-enantiomer by the favourable orientation of bicycloheptane skeleton in the cavity.
Electrochemical incorporation of carbon dioxide into alkenes by nickel complexes
Derien, Sylvie,Clinet, Jean-Claude,Dunach, Elisabet,Perichon, Jacques
, p. 5235 - 5248 (2007/10/02)
Electrogenerated Ni(0) complexes from stable Ni(II) compounds are the catalysts for the electrochemical incorporation of carbon dioxide into carbon-carbon double bonds. Different kind of olefin derivatives have been carboxylated to afford mono- or dicarboxylic acid derivatives depending on the alkene structure. The electrolyses are carried out in one compartment cells fitted with a magnesium anode under mild conditions.
Certain optically active mono esters of dicarboxylic acids
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, (2008/06/13)
Optically active mono-esters of dicarboxylic acid of the formula III: STR1 being useful as intermediates for preparing optically active natural products or medicines; asymmetric synthesis process for preparing thereof being characterized by the reaction of an acid anhydride with an (R)- or (S)-arylacetic acid derivative; and the key substances therefor are also claimed.
Chiral rhodium-diphosphine catalyst capable of catalytic reduction of a tetramisole precursor to give a significant excess of the desired S-(-)isomer, levamisole
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, (2008/06/13)
A soluble, chiral, rhodium-containing catalyst which permits the catalytic reduction of prochiral 3-acyl-1-(2-alkoxyethyl)-4-phenyl-2-imidazolinones to chiral 3-acylimidazolidinones with a substantial excess of the desired S optical isomer. The 3-acylimidazolidinones may in turn be substantially converted to levamisole, and S isomer of tetramisole. The resolution of tetramisole to remove the R isomer is thus avoided.
