2-Amino-5-cyanopyridine → Ethyl 2-(6-cyanoimidazo[1,2-a]pyridin-3-yl)acetate
Reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]#[N:9])=[CH:4][N:3]=1.[CH2:10]([O:12][C:13](=[O:18])/[CH:14]=[CH:15]/[CH:16]=O)[CH3:11]>C(#N)C>[CH2:10]([O:12][C:13](=[O:18])[CH2:14][C:15]1[N:3]2[CH:4]=[C:5]([C:8]#[N:9])[CH:6]=[CH:7][C:2]2=[N:1][CH:16]=1)[CH3:11]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 90 °C
Procedure
2-Amino-5-cyanopyridine (5.0 g, 39.9 mmol) and ethyl-(E)-4-oxobutenoate (5.92 g, 43.9 mmol, 1.1 equiv) are dissolved in acetonitrile (25 ml). The solution is heated for 14 hours at 90° C. After cooling, volatiles are removed in vacuo, and the residue is purified by flash chromatography (gradient hexane/EtOAc 100:0 to 50:50) to afford the title compound (2.77 g, 29%). 1H NMR (400 MHz, d6-DMSO): δ=9.17-9.15 (m, 1H), 7.60 (dd, J=9.3/1.0 Hz, 1H), 7.54 (s, 1H), 7.37 (dd, J=9.3/1.7 Hz, 1H), 4.07 (s, 2H), 3.99 (q, J=7.4 Hz, 2H), 1.07 (t, J=7.1 Hz, 3H). MS (ES+): 230 (M+H)+.