N-Desalkyl-3-hydroxyflurazepam → HCID 13125988, compound

Participants

Reaction Steps

A well stirred suspension of 3.0 g (0.01 mole) of 3-hydroxy-1,3-dihydro-7-chloro-5-(2-fluorophenyl)-2H-1,4-benzodiazepin-2-one in 150 ml of methylene chloride was cooled to -70°, and 7.5 ml (0.06 mol) of diethylaminosulfur trifluoride was added dropwise over a period of 10 min. The reaction mixture was then allowed to warm slowly over a period of 26 min. to -10° and then poured into 200 ml of ice water. The organic layer was separated, dried over MgSO4, and evaporated to dryness under reduced pressure to give 2.95 g (98%) of crude product. Recrystallization from benzene-heptane gave 2.00 g (67%) of 3-fluoro-1,3-dihydro-7-chloro-5-(2-fluorophenyl)-2H-1,4-benzodiazepin-2-one as off-white crystals: mp 206°-207° (dec); 1H nmr (DMSO-d6) δ 5.95 ppm (d, J = 56 Hz, 1H), 7.47 ppm (m, 7H), 11.25 ppm (s, 1H); 19F nmr (DMSO-d6) δ -162.0 ppm (d, J = 56 Hz, 1F) and δ -113.0 ppm (m, 1F).

Provenance & Evidence