Ethanol → Ethyl 2-aminopyridine-3-carboxylate
Reaction equation
[NH2:1][C:2]1[N:10]=[CH:9][CH:8]=[CH:7][C:3]=1[C:4]([OH:6])=[O:5].OS(O)(=O)=O.C([O-])([O-])=O.[Na+].[Na+].[CH2:22](O)[CH3:23]>>[NH2:1][C:2]1[N:10]=[CH:9][CH:8]=[CH:7][C:3]=1[C:4]([O:6][CH2:22][CH3:23])=[O:5]Participants
Conditions
- Temperature
- 120 °C
Procedure
Absolute ethanol (10 mL) was added to 2-aminonicotinic acid (120, commercially available) (3.9 g, 28 mmol). To the resulting stirred mixture was added H2SO4 (96%, 5 mL). The mixture was heated and refluxed at 120° C. for ~4 h. The suspension was cooled to room temperature, poured over ice (30 g), and neutralized to pH 5 using solid Na2CO3. The aqueous suspension was extracted with EtOAc (3×25 mL). These combined organic extracts were washed with water (3×30 mL), dried (Na2SO4), and rota-evaporated to dryness, leaving the title compound as off-white crystals (2.8 g, 60%); mp 90.5°-92.5° C. (Lit., 94°-95° C., Hirai, E., Chem. Pharm. Bull. 14:861 (1966)). 1H NMR (CDCl3): δ1.38 (t, J=7.2, 3, CH3CH2), 4.34 (q, J=7.2, 2, CH3CH2O), 6.40 (bm, 2, NH2), 6.62 (dd, J1 =4.9, J2 =7.8, 1, H-4), 8.14 (dd, J1 =1.0, J2 =8.4, 1, H-5), 8.21 (dd, J1 =1.2, J2 =3.8, 1, H-6).
Workup
- temperatureThe mixture was heated
- temperatureThe suspension was cooled to room temperature
- extractionThe aqueous suspension was extracted with EtOAc (3×25 mL)
- washThese combined organic extracts were washed with water (3×30 mL)
- dry with materialdried (Na2SO4)
- customrota-evaporated to dryness
Sources & evidence
- ORD record
- ord-18d95160b7284c0c9c9d70109fadf9f0
- Source dataset
- uspto-grants-1998_09
- Patent number
- US05801183
Reaction notes
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