Methylamine → Methyl 4-(methylamino)-3-nitrobenzoate

After dissolving 4-fluoro-3-nitrobenzoic acid methyl ester (507.3 mg, 2.55 mmol) in tetrahydrofuran (1 ml), methylamine (2.0 M tetrahydrofuran solution, 2.55 ml, 5.09 mmol) was added in an ice bath, and the mixture was stirred at room temperature overnight; The reaction mixture was concentrated under reduced pressure and dissolved in ethyl acetate (20 ml), and after washing in saturated aqueous sodium bicarbonate and brine, it was dried over anhydrous magnesium sulfate. It was then concentrated under reduced pressure, the obtained residue was dissolved in a methylamine-tetrahydrofuran solution (2.0 M, 3 ml), and upon sealing, the solution was stirred at 50° C. for 5 hours. The reaction mixture was concentrated under reduced pressure and dissolved in ethyl acetate (30 ml), and the solution was washed with saturated aqueous sodium bicarbonate and brine and then dried over anhydrous magnesium sulfate. The dried product was concentrated under reduced pressure to obtain 4-methylamino-3-nitro-benzoic acid methyl ester. The compound was identified by LC-MS.

1. additionwas added in an ice bath
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. dissolutiondissolved in ethyl acetate (20 ml)
4. washafter washing in saturated aqueous sodium bicarbonate
5. dry with materialbrine, it was dried over anhydrous magnesium sulfate
6. concentrationIt was then concentrated under reduced pressure
7. dissolutionthe obtained residue was dissolved in a methylamine-tetrahydrofuran solution (2.0 M, 3 ml)
8. stirringthe solution was stirred at 50° C. for 5 hours
9. concentrationThe reaction mixture was concentrated under reduced pressure
10. dissolutiondissolved in ethyl acetate (30 ml)
11. washthe solution was washed with saturated aqueous sodium bicarbonate and brine
12. dry with materialdried over anhydrous magnesium sulfate
13. concentrationThe dried product was concentrated under reduced pressure

ORD record

ord-1af70feea21f4c1b8b2c2c71b721431c

Source dataset

uspto-grants-2009_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07517875B2