Popis: |
Silylsubstituted tetrahydrofuro-[2,3- d ]-isoxazoles were prepared by the [2+3] cycloaddition of nitrile oxides to 5-(2,3-dihydrofuryl)silanes. Compounds with two condensed bicycles at the silicon atom: bis[6a-(3-methyl-3a,4,5,6a-tetrahydrofuro-[2,3- d ]-isoxazolyl)]dimethyl and bis[6a-(3-methyl-3a,4,5,6a-tetrahydrofuro-[2,3- d ]-isoxazolyl)]diphenylsilanes were prepared by the addition of acetonitrile oxide to the corresponding bis[5-(2,3-dihydrofuryl)]silanes. X-ray analysis demonstrated that 3-methyl-6a-trimethylsilyl-3a,4,5,6a-tetrahydrofuro-[2,3- d ]-isoxazole exists as RR/SS enantiomers, while bis[6a-(3-methyl-3a,4,5,6a-tetrahydrofuro-[2,3- d ]-isoxazolyl)]diphenylsilane-as SSRR/RRSS enantiomers. |