Hydrochloric Acid → 1-methyl-2,3-dihydro-1H-1,3-benzodiazol-2-one

Temperature

45 °C

A solution of 1-isopropenyl-1,3-dihydro-2H-benzimidazol-2-one (30 g, 0.172 moles) in DMF (180 ml) was added dropwise over 30 minutes to a suspension of 80% sodium hydride (5.42 g, 0.181 moles) in DMF (60 ml). The reaction mixture was heated at 45° C. for 45 minutes then a solution of methyl iodide (16.1 ml, 0.258 moles) in DMF (50 ml) was added dropwise. The reaction mixture was heated at 80° C. to 90° C. for 45 minutes, cooled at room temperature and adjusted to pH 3 to 4 with 37% HCl and heated at 80° C. for 30 minutes. The reaction mixture was cooled at room temperature and poured into ice/water. The solid residue separated was filtered and dried to give 19 g of the title compound, m.p. 188° C.-190° C.

1. temperatureThe reaction mixture was heated at 80° C. to 90° C. for 45 minutes
2. temperaturecooled at room temperature
3. temperatureheated at 80° C. for 30 minutes
4. temperatureThe reaction mixture was cooled at room temperature
5. customThe solid residue separated
6. filtrationwas filtered
7. customdried

ORD record

ord-15114dcb6f7d41f1afc50ee99f522902

Source dataset

uspto-grants-2003_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06586435B2