Hydrochloric Acid → HCID 86643928, compound

To a solution of N,O-dimethylhydroxylamine hydrochloride (4.74 g, 48.6 mmol) and iPr2NEt (8.47 mL, 48.6 mmol) in CH2Cl2 (50 mL) was added AlMe3 (1.8 M solution in toluene, 27 mL, 48.6 mmol) dropwise at 0° C. under Ar atmosphere. After stirring for 1 h, a solution of methyl 1-(2-fluorophenyl)-5-methoxy-4-oxo-1,4-dihydropyridazine-3-carboxylate (4.51 g, 16.2 mmol) in CH2Cl2 (50 mL) was added dropwise, and the mixture was stirred for 1 h at 0° C. The reaction mixture was poured into ice-water, acidified with 1 M HCl aqueous solution, saturated with NaCl, and extracted with AcOEt five times. The combined extracts were dried over MgSO4, and concentrated under reduced pressure. The residue was recrystallized from AcOEt to give the title compound (3.23 g, 65% yield) as colorless crystals: mp 152-154° C.; 1H NMR (300 MHz, CDCl3): δ ppm 3.39 (3H, s), 3.71 (3H, s), 3.91 (3H, s), 7.25-7.33 (2H, m), 7.41-7.48 (1H, m), 7.65 (1H, dt, J=1.9, 7.9 Hz), 7.81 (1H, d, J=2.3 Hz). Anal. Calcd for C14H14FN3O4: C, 54.72; H, 4.59; N, 13.67. Found: C, 54.85; H, 4.54; N, 13.86.

1. stirringthe mixture was stirred for 1 h at 0° C
2. extractionextracted with AcOEt five times
3. dry with materialThe combined extracts were dried over MgSO4
4. concentrationconcentrated under reduced pressure
5. customThe residue was recrystallized from AcOEt

ORD record

ord-698fc23a351045a49d25c86697ead8db

Source dataset

uspto-grants-2013_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08435995B2