[5-(2-Benzyloxy-ethoxy)-2-nitro-phenyl]-methyl-carbamic acid methyl ester → 6-(2-Benzyloxy-ethoxy)-1-methyl-1,3-dihydro-benzoimidazol-2-one

To a solution of [5-(2-benzyloxy-ethoxy)-2-nitro-phenyl]-methyl-carbamic acid methyl ester (0.93 g, 2.58 mmol) in methanol (50 ml) and tetrahydofuran (50 ml) was added Raney Ni and the mixture was stirred under a hydrogen atmosphere (1 atm) until all starting material was consumed as indicated by TLC. The catalyst was filtered, washed generously with tetrahydofuran, and the filtrate evaporated. The residue was washed with anhydrous tetrahydofuran and evaporated (2×15 ml). The oil was dissolved in anhydrous tetrahydofuran (30 ml) and NaH was added (0.31 g, 60%, 7.75 mmol), and the reaction mixture was heated to reflux under nitrogen for 3.5 h. The reaction was quenched with NH4Cl (sat) (20 ml), water (20 ml) and ethyl acetate (20 ml). The layers were separated, and the aqueous layer was extracted with ethyl acetate (2×25 ml). The combined organics were washed with brine (25 ml), dried over MgSO4, filtered, and evaporated to give 6-(2-benzyloxy-ethoxy)-1-methyl-1,3-dihydro-benzoimidazol-2-one (0.75 g, 97%) as a solid. Analysis calculated for C17H18N2O3 : C, 68.44; H, 6.08; N, 9.39. Found: C, 68.64; H, 6.13; N, 8.96.

1. customwas consumed
2. filtrationThe catalyst was filtered
3. washwashed generously with tetrahydofuran
4. customthe filtrate evaporated
5. washThe residue was washed with anhydrous tetrahydofuran
6. customevaporated (2×15 ml)
7. dissolutionThe oil was dissolved in anhydrous tetrahydofuran (30 ml)
8. additionNaH was added (0.31 g, 60%, 7.75 mmol)
9. temperaturethe reaction mixture was heated
10. temperatureto reflux under nitrogen for 3.5 h
11. customThe reaction was quenched with NH4Cl (sat) (20 ml), water (20 ml) and ethyl acetate (20 ml)
12. customThe layers were separated
13. extractionthe aqueous layer was extracted with ethyl acetate (2×25 ml)
14. washThe combined organics were washed with brine (25 ml)
15. dry with materialdried over MgSO4
16. filtrationfiltered
17. customevaporated

ORD record

ord-4bfd9feaa2434199a26679b662dd9c1c

Source dataset

uspto-grants-2000_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06124323