Stereocontrolled conversion of some optically active (4S,5R)-dihydroisoxazoles into acyclic 3-acetamido-1,2-diols
作者:Jamie F Bickley、Stanley M Roberts、Ye Runhui、John Skidmore、Corina B Smith
DOI:10.1016/s0040-4020(03)00868-8
日期:2003.7
Optically active (4S,5R)-dihydroisoxazoles 5a–c (90–91% ee) have been prepared by reaction of the epoxyketones 4a–c with hydroxylamine. Reduction of compounds 5a and 5b using lithium aluminium hydride took place exclusively from the Re face to give (1R,2S,3S)-1,3-disubstituted-3-aminopropane-1,2-diols 6a and 6b. These amino-diols were characterised by N-acetylation and the stereochemical sense of the
Manganese-Catalyzed 5-Endo-trig Oxygenative Cyclization of α,β-Unsaturated Oximes under Air and Ambient Conditions for the Synthesis of 4,5-Dihydroisoxazoles
The stereoselective 5-endo-trig oxygenativecyclization of α,β-unsaturatedoximes was achieved using molecular oxygen (O2) and a manganese catalyst. Several 4-hydroxy-4,5-dihydroisoxazoles were obtained in high yields by directly incorporating O2 from the atmosphere (eliminating the necessity for a pure oxygen environment) and using an unprecedentedly low loading of Mn(acac)3 (as little as 0.020 mol
A facile method for the preparation of 4-hydroxy-Δ2-isoxazolines via a cycloaddition/oxidation procedure employing nitrile oxides and vinylboronic esters
作者:Richard H. Wallace、Jinchu Liu
DOI:10.1016/s0040-4039(00)78326-2
日期:1994.10
The 1,3-dipolar cycloaddition of aromatic nitrile oxides with trans-1,2-disubstituted vinylboronic esters affords the 4-boronic ester substituted Delta(2)-isoxazoline as the major regioisomer. If the reaction mixture is treated with t-BuOOH the corresponding 4-hydroxy-Delta(2)-isoxazolines are obtained in good yield.
Hansen, John F.; Georgiou, Paul J., Journal of Heterocyclic Chemistry, 1994, vol. 31, # 6, p. 1487 - 1492
作者:Hansen, John F.、Georgiou, Paul J.
DOI:——
日期:——
Ooi, Ngan Sim; Wilson, David A., Journal of Chemical Research, Miniprint, 1980, # 12, p. 4726 - 4736