ASYMMETRIC 1.3-DIPOLAR CYCLOADDITIONS OF NITRILE OXIDES AND NITRONES WITH FLUOROSUBSTITUTED CHIRAL VINYL SULFOXIDES

The reaction of nitrile oxides 2 or nitrones 5 with chiral and optical ly pure methyl enol ethers of (R(s))-1-fluoroalkyl-2-(p-tolylsulfinyl) ethanones 1 leads with high regio-and diastereo-selectivity to the (4S ,5R,R(S))-4,5-dihydroisoxazoles 3 or (3S,4S,5R,R(S))-isoxazolidines 6; the absolute stereochemistry of the compounds has been determined usi ng X-ray diffraction and NMR analyses.