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Chiral Nitrones (chiral + nitrone)
Selected AbstractsChemInform Abstract: A New Approach to 3-Hydroxyprolinol Derivatives by Samarium Diiodide-Mediated Reductive Coupling of Chiral Nitrone with Carbonyl Compounds.CHEMINFORM, Issue 49 2009Shao-Feng Wu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Regio- and stereoselective synthesis of isoxazolidine derivatives by asymmetric 1,3-dipolar cycloaddition reaction of chiral nitrones with 1-propene-1,3-sultoneJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2008Hong-Kui Zhang Asymmetric 1,3-dipolar cycloadditions of chiral nitrones to 1-propene-1,3-sultone (1) were investigated. Chiral nitrones 6a-e reacted with sultone 1 in toluene at 90 °C for 24-36 h to give the corresponding isoxazolidines in moderate yields with high regioselectivities and stereoselectivities. The diastereoselectivity of this reaction varied with the choice of dipolarophile and the steric demands of nitrones. When sultone 1 was allowed to react chiral nitrone 6e, a much better diastereoselectivity of up to 5.1:1 was observed. [source] Synthesis and Structural Characterization of Planar Chiral Cr(CO)3 -Complexed Aromatic Nitrones , Valuable Substrates for Asymmetric SmI2 -Induced Coupling ReactionsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 5 2010Murielle Chavarot-Kerlidou Abstract The synthesis of Cr(CO)3 -complexed aromatic nitrones 2 is reported. These new planar-chiral complexes were fully characterized in solution by 1H and 13C NMR, IR and cyclic voltammetry. Moreover, structural data were obtained from X-ray structures of nitrones 2b, 2d, 2e and 2f. These analyses converge to give evidence of a favoured anti conformation of ortho -substituted nitrones, with an unusual N,O···Haryl intramolecular interaction forming a six-membered ring. The reactivity of these chiral nitrones in SmI2 -induced pinacol-type reactions was investigated. The reductive cross-coupling of nitrones 2a,d with carbonyl compounds proved to be highly chemo- and diastereoselective and afforded precursors of enantioenriched ,-amino alcohols in excellent yields. [source] Regio- and stereoselective synthesis of isoxazolidine derivatives by asymmetric 1,3-dipolar cycloaddition reaction of chiral nitrones with 1-propene-1,3-sultoneJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 4 2008Hong-Kui Zhang Asymmetric 1,3-dipolar cycloadditions of chiral nitrones to 1-propene-1,3-sultone (1) were investigated. Chiral nitrones 6a-e reacted with sultone 1 in toluene at 90 °C for 24-36 h to give the corresponding isoxazolidines in moderate yields with high regioselectivities and stereoselectivities. The diastereoselectivity of this reaction varied with the choice of dipolarophile and the steric demands of nitrones. When sultone 1 was allowed to react chiral nitrone 6e, a much better diastereoselectivity of up to 5.1:1 was observed. [source] | ||||||||||