Iodine → HCID 178489659, compound

Participants

Reaction Steps

Crushed potassium hydroxide (1.35 g, 24.1 mmol) was added in one portion to a solution of 5-(3-methoxyphenyl)-1H-thieno[3,2-c]pyrazole [1.85 g, 8.03 mmol, Intermediate (53)] and dimethylformamide at 0° C. with stirring. After 10 minutes, iodine (3.05 g, 12.0 mmol) was added in one portion and the dark reaction was stirred at 0° C. for 30 minutes and then at room temperature for 5 hours. The reaction was quenched with 10% aqueous NaHSO3 (100 mL), the resulting white mixture diluted with water (100 ml) and the mixture aged at 5° C. overnight. The solid was collected by filtration, washed with water (3×30 mL) and dried under vacuum at 40° C. to give 3-iodo-5-(3-methoxyphenyl)-1H-thieno[3,2-c]pyrazole [2.61 g, 91%, Intermediate (54)] as a tan powder. mp 159-163° C.; TLC Rf 0.54 (silica, 80% ethyl acetate/heptane); LC/MS: 357.0 (M+H), RT=3.60 minutes; 1H NMR (300 Mhz, CDCl3) δ 11.3 (br s, 1H), 7.33 (m, 1H), 7.28-7.20 (m, 2H), 7.14 (m, 1H), 6.91 (m, 1H), 3.87 (s, 3H).

Provenance & Evidence