Diphenyl Ether → 4-Oxo-4,5-dihydrothieno[3,2-c]pyridine-7-carbonitrile

Reaction equation

C1([O:7][C:8]2C=CC=CC=2)C=CC=CC=1.C([N:18](CCCC)CCCC)CCC.[C:27]([C:29]([C:36]1[S:37][CH:38]=[CH:39][CH:40]=1)=[CH:30]C(N=[N+]=[N-])=O)#[N:28]>C(Cl)Cl>[O:7]=[C:8]1[C:40]2[CH:39]=[CH:38][S:37][C:36]=2[C:29]([C:27]#[N:28])=[CH:30][NH:18]1

Participants

Procedure

To a stirring solution of diphenyl ether (1.5 L) and trin-butylamine (0.3 L) heated to an equilibrated temperature of 215° C. was dropwise added a solution of 3-cyano-3-thiophen-2-yl-acryloyl azide 23 (85 g, 0.416 mol) in CH2Cl2 (340 mL). The temperature was maintained between 210–215° C. during this time. Following addition, the reaction was stirred a further 30 min, then allowed to cool to room temperature, during which the pure product precipitated from solution. The product was filtered and washed with copious hexane. Drying the precipitate under vacuum provided 58.4 g of 24. 1H NMR (400 MHz, d6-DMSO) δ 12.36 (s, 1H), 8.27 (s, 1H), 7.81 (d, J=5 Hz, 1H), 7.57 (d, J=5 Hz 1H).