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-7f93e0f925804b54b5092c8ac4156c7a

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08513251B2