[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 dimethylforamide 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, 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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