A Convenient One-Pot Synthesis of 4-Substituted 3,5-Bis(alkoxycarbonyl) -4,5-dihydroisoxazole 2-Oxides from Aldehydes and Nitroacetic Esters in a Solid-Liquid Reaction System and Subsequent Deoxygenation
A Convenient One-Pot Synthesis of 4-Substituted 3,5-Bis(alkoxycarbonyl) -4,5-dihydroisoxazole 2-Oxides from Aldehydes and Nitroacetic Esters in a Solid-Liquid Reaction System and Subsequent Deoxygenation
4-Substituted 3,5-bis(alkoxycarbonyl)-4,5-dihydroisoxazole 2-oxides are obtained from nitroacetic esters and imines which are prepared from aldehydes and isopropylamine in the presence of molecular sieves. Reduction of the N-oxides with trimethyl phosphite in dioxane gives the corresponding 4,5-dihydroisoxazoles in good yields.
Highly diastereoselective condensation of α-nitro-esters with aldehydes catalyzed by zinc complexes of amino acids
作者:A. Chatterjee、S.C. Jha、N.N. Joshi
DOI:10.1016/s0040-4039(02)01047-x
日期:2002.7
Zinc complexes of amino acids efficiently catalyze the condensation between α-nitro-esters and a variety of aldehydes. An unusual domino reaction sequence leads to the diastereoselective formation of substituted isoxazoline N-oxides in high yields.