[CH2:1]([O:3][C:4](=[O:12])[C:5]1[CH:10]=[CH:9][CH:8]=[N:7][C:6]=1Cl)[CH3:2].[OH:13][C:14]1[CH:15]=[CH:16][C:17]2[C:18]([CH:22]=1)=[N:19][O:20][N:21]=2.C(=O)([O-])[O-].[Cs+].[Cs+].O>CN(C)C=O>[CH2:1]([O:3][C:4](=[O:12])[C:5]1[CH:10]=[CH:9][CH:8]=[N:7][C:6]=1[O:13][C:14]1[CH:15]=[CH:16][C:17]2=[N:21][O:20][N:19]=[C:18]2[CH:22]=1)[CH3:2]A mixture of 5.5 g (29.4 mmol) 2-chloro nicotinic acid ethyl ester, 4.0 g (29.4 mmol) 5-hydroxybenzofurazan and 20.1 g (61.7 mmol) cesium carbonate in 125 ml dry dimethylformamide was heated at 90° C. for five days. The mixture was poured into water and extracted with ethyl acetate. The ethyl acetate extracts were combined; washed successively with sodium bicarbonate solution, water, and brine; then dried (Na2SO4); and concentrated in vacuo to give a solid. Recrystallization from diethyl ether/pentane gave 2.2 g (26%) solid.
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