Hydrochloric Acid → 5-Amino-4,5,6,7-tetrahydrobenzimidazole dihydrochloride

温度

80 °C

Add 5% Rh/C (5.215 g) to a 500 ml glass Parr bottle. Purge the bottle with nitrogen and wet the 5% Rh/C with 3 N HCl (50 ml). Then add 6-nitro-1H-benzoimidazole (10.354 g, 0.0635 mol) and 3N HCl (100 ml) to the purged bottle. Seal the Parr bottle and purge the reaction vessel with nitrogen (3×) and with hydrogen (3×). Then pressurize the reaction mixture with hydrogen (60 psig), seal the vessel but add hydrogen as needed to maintain 60 psig, agitate the reaction and heat to 80° C. Continue the reaction for 24 hours then turn off the heat and allow the reaction mixture to cool to ambient temperature. Vent the excess hydrogen from the vessel, purge the vessel with nitrogen (3×) and filter the reaction mixture to remove the 5% Rh/C catalyst. The filtrate is concentrated to dryness on a rotary evaporator and then under high vacuum. Dissolve the solid residue in 20 mL of methanol, heat to approximately 60° C. and add additional methanol (approximately up to 10 mL or as needed) to dissolve the residue completely. Cool the solution to room temperature and add ether (40 mL). A white solid separates, filter and dry under high vacuum to give the product (8.gm).

1. customPurge the bottle with nitrogen
2. customSeal the Parr bottle
3. custompurge the reaction vessel with nitrogen (3×)
4. customseal the vessel
5. additionadd hydrogen
6. temperatureto maintain 60 psig
7. customthe reaction
8. customthe reaction for 24 hours
9. temperatureheat
10. temperatureto cool to ambient temperature
11. customVent the excess hydrogen from the vessel, purge the vessel with nitrogen (3×)
12. filtrationfilter the reaction mixture
13. customto remove the 5% Rh/C catalyst
14. concentrationThe filtrate is concentrated to dryness on a rotary evaporator
15. dissolutionDissolve the solid residue in 20 mL of methanol
16. temperatureheat to approximately 60° C.
17. additionadd additional methanol (approximately up to 10 mL
18. dissolutionto dissolve the residue completely
19. temperatureCool the solution to room temperature
20. additionadd ether (40 mL)
21. filtrationA white solid separates, filter
22. customdry under high vacuum
23. customto give the product (8.gm)

ORDレコード

ord-be7ef69e8ba34bff9b39e8055ecd4d63

出典データセット

uspto-grants-2010_10

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US07820659B2