[O:1]1[CH:5]=[CH:4][C:3]([C:6]2(O)[C:14]3[O:13][N:12]=[C:11]([CH3:15])[C:10]=3[CH2:9][CH2:8][CH2:7]2)=[CH:2]1.C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[O:1]1[CH:5]=[CH:4][C:3]([C:6]2[C:14]3[O:13][N:12]=[C:11]([CH3:15])[C:10]=3[CH2:9][CH2:8][CH:7]=2)=[CH:2]1To a mixture of 7.6 g (0.034 mol) of 7-(3-furyl)-3-methyl-4,5,6,7-tetrahydro-benzisoxazol-7-ol in 300 ml of toluene was added 100 mg of p-toluenesulfonic acid and the mixture was placed on a Rotovap, and the solvent was distilled in vacuo (80° C.) until an oil residue was obtained. Toluene (200 ml) was added to the above residue, the mixture was placed on Rotovap, and the solvent was distilled in vacuo to complete the reaction. The oil was chromatographed (silica, 1:1 hexane/methylene chloride) to afford 3.36 g (95%) of 7-(3-furyl)-3-methyl-4,5-dihydrobenzisoxazole, (Formula III: R2 =H; ##STR8## R4 =3-furanyl) as a clear oil.
Wird geladen…