Tetrahydrofuran → HCID 23598831, compound

Participants

Reaction Steps

To a suspension of 7,8-difluoro-1-(4-iodo-2-methyl-phenyl)-4-oxo-1,4-dihydro-2H-benzo[d][1,3]oxazine-6-carboxylic acid (0.3 g, 0.67 mmol) in N,N-dimethylformamide (3 mL) is added trifluoroacetic acid pentafluorophenyl ester (0.127 mL, 0.74 mmol) and pyridine (0.60 mL, 0.74 mmol). After stirring for 4 hours the reaction mixture is diluted with ethyl acetate and washed 3 times with 1.0 M HCl solution, 3 times with 5% aqueous NaHCO3 solution, 2 times with water and once with saturated brine solution. The organic layers were collected and dried over Na2SO4, filtered and concentrated in vacuo affording 7,8-difluoro-1-(4-iodo-2-methyl-phenyl)-4-oxo-1,4-dihydro-2H-benzo[d][1,3]oxazine-6-carboxylic acid pentafluorophenylester as a dark orange oil (0.34 g, 83.1%). To a suspension of 7,8-difluoro-1-(4-iodo-2-methyl-phenyl)-4-oxo-1,4-dihydro-2H-benzo[d][1,3]oxazine-6-carboxylic acid pentafluorophenylester (0.33 g, 0.54 mmol) in freshly distilled THF (10 mL) is added methylamine hydrochloride (0.037 g, 0.54 mmol) and N,N-diisopropylethylamine (0.019 mL, 1.08 mmol). After stirring for 17 hours, the reaction mixture was diluted with ethyl acetate and washed 2 times with water and 2 times with saturated brine solution. The organic layers were collected and dried over Na2SO4, filtered and concentrated in vacuo affording 7,8-difluoro-1-(4-iodo-2-methyl-phenyl)-4-oxo-1,4-dihydro-2H-benzo[d][1,3]oxazine-6-carboxylic acid methylamide as a yellow solid (0.19 g, 76.9%); mp 219–223° C.; 1NMR (400 MHz; DMSO-d6) 8.40 (s, 1H), 8.06 (d, 1H, J=6.8), 7.74 (s, 1H), 7.50 (d, 1H, J=8.4), 6.87 (d, 1H, J=8.0), 5.61 (s, 2H), 2.76 (d, 3H, J=4.4), 2.25 (s, 3H); MS(APCI)m+1=459; Anal.calcd/found for C17H13F2IN2O3 C 45.00/45.39, H 3.01/3.16, N 6.05/5.88.

Provenance & Evidence