反应详情

5-(Hydroxymethyl)-1 (3H)-isobenzofuranone (2.94 g, 17.9 mmol) obtained from Example 4-(2) was dissolved in tetrahydrofuran (100 ml), and activated manganese dioxide (31 g) was added thereto. The mixture was stirred at room temperature for 30 minutes, and an additional amount of activated manganese dioxide (3 g) was added thereto. The resulting mixture was stirred for a further 30 minutes and then filtered. The solid filtered off was washed with tetrahydrofuran, and the washings were combined with the previous filtrate, then the combined solution was concentrated under reduced pressure to give a solid residue. The residue was subjected to chromatography on a silica gel (150 g) column (eluent; ethyl acetate:dichloromethane=0:1˜1:10). The eluate was concentrated under reduced pressure to afford a solid compound, which was washed with a mixed solvent of ethyl acetate-hexane (1:2) to afford the title compound (2.01 g, 69% yield) as a solid (mp. 160° C.)

1. stirringThe resulting mixture was stirred for a further 30 minutes
2. filtrationfiltered
3. filtrationThe solid filtered off
4. washwas washed with tetrahydrofuran
5. concentrationthe combined solution was concentrated under reduced pressure
6. customto give a solid residue
7. concentrationThe eluate was concentrated under reduced pressure
8. customto afford a solid compound, which
9. washwas washed with a mixed solvent of ethyl acetate-hexane (1:2)