Potassium thiocyanate → 4-(2-Chloropyridin-4-yl)-5-(4-fluorophenyl)-1,3-dihydroimidazole-2-thione

Participants

Reaction Steps

With gentle heating, 23a (2.9 g; about 9.6 mmol) was dissolved in absolute DMF (75 ml). Potassium thiocyanate (1.9 g; 19.6 mmol) was introduced into the clear orange-red solution: immediate opalescence and a lighter color. The reaction mixture was stirred under reflux for 1.5 h. The suspension was cooled to room temperature and, with H2O cooling, diluted dropwise with H2O (about 140 ml). The yellow precipitate was filtered off, washed with H2O and dried under reduced pressure over CaCl2.

Provenance & Evidence