Hydrochloric Acid → 5-Bromo-1-methyl-1,3-dihydro-2H-benzo[d]imidazol-2-one

Temperature

0 °C

A solution of 4-bromo-N1-methylbenzene-1,2-diamine (581 mg, 2.89 mmol) in methylene chloride (50 mL) was cooled to 0° C. in an ice/water bath and treated dropwise with a solution of 20% phosgene in toluene (1.52 mL). When the addition was complete, triethylamine (585 mg, 5.78 mmol) was added and the reaction stirred at 0° C. for 30 min. After this time, the reaction was poured into 1 M hydrochloric acid (80 mL) and extracted with methylene chloride. The combined organic layers were washed with water and dried over sodium sulfate. The drying agent was removed by filtration and the filtrate concentrated under reduced pressure. The resulting residue was purified by trituration with ethyl acetate to afford 5-bromo-1-methyl-1H-benzo[d]imidazol-2(3H)-one. 1H NMR (400 MHz, DMSO-d6) δ 10.98 (bs, 1H), 7.17 (dd, J=8.4, 1.6 Hz, 1H), 7.10 (d, J=1.6 Hz, 1H), 7.05 (d, J=8.4 Hz, 1H), 3.26 (s, 3H).

1. additionWhen the addition
2. extractionextracted with methylene chloride
3. washThe combined organic layers were washed with water
4. dry with materialdried over sodium sulfate
5. customThe drying agent was removed by filtration
6. concentrationthe filtrate concentrated under reduced pressure
7. customThe resulting residue was purified by trituration with ethyl acetate

ORD record

ord-772655827cbd4a8f8549acdbfb6a988f

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09376441B2