HCID 18404138, compound → HCID 19075193, compound

Participants

Reaction Conditions

Reaction Steps

One equivalent of 2-chloromethyl-4-(3-chloropropylthio)-3-methylpyridine hydrochloride (dissolved in 10 ml of water) is added dropwise at 40° C. in the course of 20 min. to a solution of 2-mercapto-1H-benzimidazole (1.5 g/10 mmol) in 40 ml of ethanol and 21 ml of 1 N sodium hydroxide solution. The mixture is then stirred for 2-3 h at 50-60° C. and a further 3-4 h at room temperature, ethanol is distilled off on a rotary evaporator (1 kPa/40° C.), the residue is extracted 3 times with 20 ml of dichloromethane each time, and the extracts are washed with 0.1 N sodium hydroxide solution, dried over potassium carbonate and concentrated completely in vacuo. For purification, the crude product is chromatographed on silica gel (dichloromethane/methanol 20:1); the collected pure fractions are jointly concentrated in vacuo and the residue is crystallized from dichloromethane/diisopropyl ether. It is then recrystallized from methanol/toluene. Yield 2.67 g (74%) of the title compound as a colorless solid of m.p. 112-114° C.

Provenance & Evidence