反应详情

5% Palladium on carbon type 87L paste (22 g) was added to 7-[(1R)-2-azido-1-hydroxy-ethyl]-4-hydroxy-3H-benzothiazol-2-one (example 1, step c) (225 g) dissolved in ethanol (3 L). The reaction was stirred under hydrogen (3 bar) for 48 h. A further 10 g of the catalyst was added and hydrogenation continued for a further 5 days. The reaction mixture was filtered and the solid (product+catalyst) suspended in ethanol (2.5 L) then acetic acid (150 mL) was added and the whole stirred overnight. The mixture was filtered again to remove the palladium on carbon catalyst. The solution was evaporated to dryness and azeotroped with toluene (2×1 L). The solid was slurried in tetrahydrofuran (1 L) for 4 hours, filtered and dried at 40° C. in vacuo to give the subtitled compound. Yield 57 g.

1. waithydrogenation continued for a further 5 days
2. filtrationThe reaction mixture was filtered
3. additionacetic acid (150 mL) was added
4. stirringthe whole stirred overnight
5. filtrationThe mixture was filtered again
6. customto remove the palladium on carbon catalyst
7. customThe solution was evaporated to dryness
8. customazeotroped with toluene (2×1 L)
9. waitThe solid was slurried in tetrahydrofuran (1 L) for 4 hours
10. filtrationfiltered
11. customdried at 40° C. in vacuo