67111-68-6Relevant academic research and scientific papers
A General, Multitechnique Approach to the Stereochemical Characterization of 1,2-Diarylethane-1,2-diols
Rosini, Carlo,Scamuzzi, Simone,Focati, Marco Pisani,Salvadori, Piero
, p. 8289 - 8293 (1995)
A general method which allows the nonempirical stereochemical characterization of 1,2-diarylethane-1,2-diols, obtained by the Sharpless catalytic dihydroxylation of (E)-ArCR=CHAr' olefins, has been devised.The basis of the method is the transformation into the corresponding ketals with acetone.These derivatives can be resolved on the Daicel Chiralcel OD column, allowing the determination of the ee, while the absolute configuration is assigned by the analysis of their circular dichroism (CD) spectra and by the helicity of the cholesteric phase induced in nematic liquid crystals.
Novel biphenyl organocatalysts for iminium ion-catalyzed asymmetric epoxidation
Farah, Mohamed M.,Page, Philip C. Bulman,Buckley, Benjamin R.,Blacker, A. John,Elsegood, Mark R.J.
, p. 758 - 769 (2013/07/27)
Two novel chiral biphenyl iminium salts derived from L-acetonamine, containing electron-withdrawing 3,30-substituents on the biphenyl unit, have been prepared and tested as asymmetric catalysts for epoxidation of prochiral alkenes. The results are compared with those achieved using the corresponding unsubstituted system.
Hot water as a mild Bronsted acid catalyst in ring opening reactions of epoxides
Xu, Zhaobing,Qu, Jin
experimental part, p. 1718 - 1725 (2012/04/18)
Ring opening of extremely hydrophobic epoxides with water, amines, sodium azide and thiophenol was realized in the mixture solvent of water and 1, 4-dioxane under reflux condition. Hot water was believed to act as a mild Bronsted acid catalyst in the epoxide-opening reactions.
Oxiranyl anion-mediated synthesis of highly enantiomerically enriched styrene oxide derivatives
Capriati, Vito,Florio, Saverio,Luisi, Renzo,Salomone, Antonio
, p. 2445 - 2448 (2007/10/03)
(Matrix presented) The stereospecific α-lithiation of optically active styrene oxides and the trapping reaction of the corresponding highly reactive intermediates with electrophiles to produce optically active styrene oxide derivatives are described. This methodology has been applied to the synthesis of an optically active oral antifungal agent of industrial interest.
Diastereomerically Pure 3-(Silyloxy)oxetanes by a Selective Paterno-Buechi Reaction
Bach, Thorsten,Joedicke, Kai
, p. 2457 - 2466 (2007/10/02)
Diastereomerically pure 3-oxetanes 3 were prepared in moderate to good yields (45-72percent) by the Paterno-Buechi reaction of silyl enol ethers 2 with benzaldehyde.The phorocycloaddition exhibits a high degree of regio- and diastereoselectivity.The substituents R in the silyl enol ether have been varied , and it was found that steric bulk is mainly responsible for enhanced selectivity (diastereoselectivity from 70:30 up to 95:5).The regiochemical control is perfect (regioselectivity > 95:5) except for silyl enol ether 2a (R = Me) in the case of which a 90:10 ratio of regioisomers was observed.Irradiation of the reaction mixture at lower temperature (-25 deg C) led to a further improvement of diastereoselectivity.The relative configuration of the products obtained was elucidated both by 1H-NMR spectroscopy and by chemical degradation.As a mechanistic hypothesis to explain the high observed diastereoselectivity we propose that the steric environment in the intermediate diradical 11 determines the stereoselectivity according to two possible reaction pathways, i.e. bond formation and retrocleavage. - Key Words: Paterno-Buechi reaction / Oxetanes / Diastereoselectivity / Enol silyl ethers / Photocycloaddition
Anionic Zirconaoxiranes as Nucleophilic Aldehyde Equivalents. Application to Intermolecular Pinacol Cross Coupling
Askham, Fredric R.,Carroll, Kevin M.
, p. 7328 - 7329 (2007/10/02)
Selective intermolecular pinacol cross coupling is achieved by reaction of anionic zirconaoxiranes with aromatic aldehydes and ketones, thereby providing an efficient route to unsymmetrical vicinal diols.
