Methylhydrazine → HCID 58541909, compound

To a solution of N-[1-dimethylamino-meth-(E)-ylidene]-5-fluoro-phthalamic acid methyl ester plus regioiosmer (2.9 g, 11.50 mmol) in acetic acid (10 mL) is added methyl hydrazine (6.0 mL, 113.95 mmol). The reaction mixture is stirred at room temperature for 1 hour. The reaction mixture is diluted with EtOAc (250 mL) and the organic layer is washed with H2O (150 mL×2), dried with Na2SO4 and filtered. The filtrate is concentrated under reduced pressure. The residue is triturated with 1:1 EtOAc:hexanes (200 mL), and filtered to remove the white solid. The mother liquor is concentrated under reduced pressure and the residue is purified by silica gel flash column chromatography with 7.5% MeOH in CH2Cl2 as the eluent to afford 5-fluoro-2-(2-methyl-2H-1,2,4-triazol-3-yl)-benzoic acid methyl ester plus regioisomer (1.5 g, 55%).

1. washthe organic layer is washed with H2O (150 mL×2)
2. dry with materialdried with Na2SO4
3. filtrationfiltered
4. concentrationThe filtrate is concentrated under reduced pressure
5. customThe residue is triturated with 1:1 EtOAc
6. filtrationhexanes (200 mL), and filtered
7. customto remove the white solid
8. concentrationThe mother liquor is concentrated under reduced pressure
9. customthe residue is purified by silica gel flash column chromatography with 7.5% MeOH in CH2Cl2 as the eluent

ORD record

ord-3c8a73458d9d4e6d837301c2e965508f

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08420655B2