Iodoethane → Ethyl 2-aminopyridine-3-carboxylate

A 60% sodium hydride suspension in mineral oil (1.28 g, 32 mMol) was added to a stirring suspension of 2-aminonicotinic acid (4.21 g, 30 mMol) in DMF (50 mL), and the mixture was gently heated until gas evolution was observed. The suspension was stirred at room temperature for 4 hours, after which a homogeneous amber solution was observed. Iodoethane (4.75 g, 30 mMol) was added, and the mixture was allowed to stir overnight at room temperature. The solution was concentrated in-vacuo, the residue was taken up in 9:1 ethyl acetate/hexane (200 mL), washed with water (5×50 mL), and brine (50 mL), dried over sodium sulfate, then concentrated in-vacuo. The residue was purified over silica gel, eluting with 25%–50% ethyl acetate/hexane, to yield 3.6 g of colorless solids as product. NMR (500 MHz, DMSO) δ 8.20 (dd, 1H, J=5 Hz, 2 Hz), 8.06 (dd, 1H, J=8 Hz, 2 Hz), 7.16 (s, 2H), 6.63 (dd, 1H, J=8 Hz, 5 Hz), 4.28 (q, 2 H, J=7 Hz), 1.30 (t, 3H, J=7 Hz). Yield=72%.

1. temperaturethe mixture was gently heated until gas evolution
2. stirringto stir overnight at room temperature
3. concentrationThe solution was concentrated in-vacuo
4. washwashed with water (5×50 mL), and brine (50 mL)
5. dry with materialdried over sodium sulfate
6. concentrationconcentrated in-vacuo
7. customThe residue was purified over silica gel
8. washeluting with 25%–50% ethyl acetate/hexane

ORD record

ord-8a3a829775304609b8096ce17faa44ea

Source dataset

uspto-grants-2007_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07183270B2