Benzyl Alcohol → Sulfamic acid 4-(2-methyl-1H-imidazol-1-yl)phenyl ester monohydrochloride

To a chilled solution of acetonitrile (50 ml) and chlorosulfonyl isocyanate (12.16 g, 0.086 mole) was added benzyl alcohol (9.29 g, 0.086 mole) while maintaining the temperature between 10°-15° C. The reaction stirred at room temperature 1.5 hr and 4-(2-methyl-1H-imidazol-1-yl)phenol (10.0 g, 0.057 mole) added in small portions) while maintaining the temperature below 20° C. The reaction was stirred overnight and its progress checked by thin layer chromatography (8:1:1 ethyl acetate/methanol/ammonium hydroxide). Once the reaction had gone to completion, isopropyl alcohol (3.42 g, 0.057 mole) was added and reaction stirred an additional hour. The solution was concentrated and the residue dissolved in methanol (150 ml) and the solution subjected to catalytic hydrogenation using 5% palladium on carbon catalyst. The solution was filtered and the filtrate concentrated, replacing the methanol with isopropyl alcohol. White crystals precipitated and were collected and dried (9.8 g, 59.5%, mp 197°-200° C.).

1. temperaturewhile maintaining the temperature between 10°-15° C
2. temperaturewhile maintaining the temperature below 20° C
3. stirringThe reaction was stirred overnight
4. additionwas added
5. customreaction
6. stirringstirred an additional hour
7. concentrationThe solution was concentrated
8. dissolutionthe residue dissolved in methanol (150 ml)
9. filtrationThe solution was filtered
10. concentrationthe filtrate concentrated
11. customWhite crystals precipitated
12. customwere collected
13. customdried (9.8 g, 59.5%, mp 197°-200° C.)

ORD record

ord-01505a06caa64df3be68a2d4e17540ac

Source dataset

uspto-grants-1993_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05273993