[OH-].[K+].[C:3]1([C:9]2[S:16][C:15]3[CH:14]=[N:13][NH:12][C:11]=3[CH:10]=2)[CH:8]=[CH:7][CH:6]=[CH:5][CH:4]=1.[I:17]I.OS([O-])=O.[Na+]>O.CN(C)C=O>[I:17][C:14]1[C:15]2[S:16][C:9]([C:3]3[CH:4]=[CH:5][CH:6]=[CH:7][CH:8]=3)=[CH:10][C:11]=2[NH:12][N:13]=1
Crushed KOH (1.09 g, 6.49 mmol) was added in one portion to a stirred mixture of 5-phenyl-1H-thieno[3,2-c]pyrazole [1.30 g, 6.49 mmol, Intermediate (45)], iodine (2.47 g, 9.73 mmol), and dimethylformamide (15 mL) under nitrogen at room temperature and the dark reaction was stirred at room temperature. After 3 hours, 10% aqueous NaHSO3 (40 mL) was added with stirring. The resulting slurry was diluted with water (40 mL) and the mixture stirred at room temperature for 5 minutes. The solid was collected by filtration, washed three times with water (20 mL) and then dried under high vacuum at 40° C. to give 3-iodo-5-phenyl-1H-thieno[3,2-c]pyrazole [1.94 g 91%, Intermediate (46)] as a tan powder. TLC Rf 0.52 (silica, 70% ethyl acetate/heptane); LC/MS: 326.94 (M+H), RT=3.38 minutes; 1H NMR [600 Mhz, (CD3)2SO]: δ 13.51 (br s 1H), 7.73 (m, 2H), 7.69 (br s, 1H), 7.46 (m, 2H), 7.38 (m, 1 Hz).
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