Hydrazine → (3-Bromo-5,7-difluoro-quinolin-6-yl)-acetic acid hydrazide

SOCl2 (394 mg, 3.31 mmol) was added dropwise to a stirred solution of (3-bromo-5,7-difluoro-quinolin-6-yl)-acetic acid (500 mg, 1.65 mmol) in 12 ml of methanol at 0° C. under N2. After stirring for 2 hours at room temperature the solvent was evaporated and the crude (3-bromo-5,7-difluoro-quinolin-6-yl)-acetic acid methyl ester was used directly in the next step. To a mixture of (3-bromo-5,7-difluoro-quinolin-6-yl)-acetic acid methyl ester (2.29 g, 7.22 mmol) in methanol (100 mL) was added anhydrous hydrazine (2.31 g, 72.2 mmol). The mixture was heated at 55° C. for 4 hours. Additional anhydrous hydrazine (1.16 g, 36.1) was added and the mixture was heated at 55° C. for 2 hours. The reaction mixture was cooled to room temperature to give a white solid. The white solid was filtered and washed with cold methanol to obtain 2.1 g of the title compound (92% yield). MS: m/z 318 [M+H+]. 1H NMR (500 MHz. DMSO-d6): δ 1.99 (2H, s), 4.25 (2H, bs), 7.72 (1H, d), 8.74 (1H, s), 9.03 (1H, s), 9.35 (1H, s).

1. customwas evaporated
2. temperatureThe mixture was heated at 55° C. for 4 hours
3. temperaturethe mixture was heated at 55° C. for 2 hours
4. temperatureThe reaction mixture was cooled to room temperature
5. customto give a white solid
6. filtrationThe white solid was filtered
7. washwashed with cold methanol

ORD record

ord-81d7f29af2364e4f91899f89741279bb

Source dataset

uspto-grants-2011_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08071581B2