Methyl 3-azido-6'-methoxy-6-(4-methoxyphenyl)-2,3'-bipyridine-4-carboxylate → methyl 7-methoxy-2-(4-methoxyphenyl)-5H-pyrido[2',3':4,5]pyrrolo[2,3-b]pyridine-4-carboxylate
Reaction equation
[N:1]([C:4]1[C:5]([C:22]2[CH:23]=[N:24][C:25]([O:28][CH3:29])=[CH:26][CH:27]=2)=[N:6][C:7]([C:14]2[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=2)=[CH:8][C:9]=1[C:10]([O:12][CH3:13])=[O:11])=[N+]=[N-]>ClC1C=CC=CC=1Cl>[CH3:29][O:28][C:25]1[N:24]=[C:23]2[NH:1][C:4]3[C:9]([C:10]([O:12][CH3:13])=[O:11])=[CH:8][C:7]([C:14]4[CH:19]=[CH:18][C:17]([O:20][CH3:21])=[CH:16][CH:15]=4)=[N:6][C:5]=3[C:22]2=[CH:27][CH:26]=1Participants
3
Procedure
A solution of methyl 3-azido-6′-methoxy-6-(4-methoxyphenyl)-2,3′-bipyridine-4-carboxylate (120 mg, 0.31 mmol) in 1,2-dichlorobenzene (4 mL) was heated at 180° C. for 10 min with gas evolution. The solvent was removed under vacuum and the product was purified by silica gel radial chromatography (step gradient elution with hexane containing 50 to 100% methylene chloride). This gave methyl 7-methoxy-2-(4-methoxyphenyl)-5H-pyrido[2′,3′:4,5]pyrrolo[2,3-b]pyridine-4-carboxylate (80 mg, 72% yield) as a yellow solid. MS (ESI) m/z 364.1 (M+H). 1H NMR (CDCl3) δ ppm 9.61 (1H, s), 8.49 (1H, d, J=8.55 Hz), 8.14 (1H, s), 8.07 (2H, d, J=8.85 Hz), 7.02 (2H, d, J=8.85 Hz), 6.73 (1H, d, J=8.55 Hz), 4.06 (3H, s), 4.04 (3H, s), 3.87 (3H, s).