28981-66-0Relevant articles and documents
A facile synthesis of vicinal cis-diols from olefins catalyzed by in situ generated MnxOy nanoaggregates
Dalmizrak, Di?dem,G?ksu, Haydar,Gültekin, Mehmet Serdar
, p. 20751 - 20755 (2015/03/18)
A novel protocol for the practical and green synthesis of vicinal cis-diols from 10.0 mmol olefins by using 5.0 mmol KMnO4 as oxidant and 30.0 mmol H2O2 as co-oxidant is reported. The presented procedure is easy to carry out and enables the direct transformation of linear and cyclic alkenes to the corresponding vicinal cis-diols. The synthesis of vicinal cis-diols by dihydroxylation of olefins with a KMnO4/H2O2 system was catalyzed by in situ generated MnxOy nanoaggregates. The use of H2O2 as a co-oxidant is the key for the protocol to synthesize vicinal cis-diols in high yields, because it assists the oxidation of MnxOy nanoaggregates, which have an active role in the oxidation reaction medium.
Desymmetrization of Cyclohexadienylsilanes. Regio-, Diastereo-, and Enantioselective Access to Sugar Mimics
Angelaud, Remy,Babot, Odile,Charvat, Trevor,Landais, Yannick
, p. 9613 - 9624 (2007/10/03)
Desymmetrization of cyclohexadienylsilanes available from Birch reduction of the corresponding arylsilanes is efficiently carried out using Sharpless asymmetric dihydroxylation and aminohydroxylation. Complete diastereocontrol and reasonable enantiocontrol have been attained during the preparation of the desired diols. An excellent regiocontrol has also been observed during aminohydroxylation of dienylsilanol 6b. The resulting diol 8 and hydroxycarbamate 27 have then been elaborated further, offering a straightforward access to various types of cyclitols, aminocyclitols, carbasugars, as well as the antibiotic palitantine 4. The complete functionalization of the original arylsilanes 5 is thus typically achieved in fewer than eight steps with high stereoselectivities and excellent overall yield.
Catalytic One-Pot Osmylation of Cyclohexadienes: Stereochemical and Conformational Studies of the Resulting Polyols
Tschamber, Theophile,Backenstrass, Frederique,Fritz, Hans,Streith, Jacques
, p. 1052 - 1060 (2007/10/02)
Catalytic double osmylation is described for a series of cyclohexadienes in acetone/H2O in the presence of the co-oxidant N-methylmorpholine N-oxide (NMO).The formation of polyols occurred stereospecifically with cyclohexadienes 3, 7, and 11a, leading thereby to tetrols 5a, and 9a and to allo-inositol (14a), respectively.To the contrary, trans-cyclohexadiene-diol 15a gave a mixture of the stereoisomeric inositols 18a (epi), 19a (neo), and 20a (chiro).High-field NMR let to clearcut conformational analyses of the polyhydroxylated derivatives.