Pyridine → 5-(N-phenyloxycarbonyl-1,4-dihydro-4-pyridyl)-6-(4-fluorophenyl)-2,3-dihydroimidazo[2,1-b]thiazole

Participants

Reaction Steps

6-(4-Fluorophenyl)-2,3-dihydroimidazo[2,1-b]thiazole(10.0 g, 0.0456 mol) and 11 ml (0.136 mol) of pyridine were dissolved in 150 ml of methylene chloride. To this cooled solution (10°) was added 20.35 g (0.13 mol) of phenyl chloroformate in 20 ml of methylene chloride under a nitrogen atmosphere. During the addition, the reaction pot temperature was not allowed to rise past 15°. After the addition, the reddish-colored solution was stirred at ambient temperature for 1.5 hours, then heated under reflux for an additional 15 minutes. Thin-layer chromatography (ethyl acetate/hexane/methanol, 15:1:0.1) showed the reaction to be complete. The reaction mixture was diluted with 200 ml of water and extracted with methylene chloride (3×100 ml). The organic layer was dried, then concentrated to yield 17.0 g (89%) of 5-(N-phenyloxycarbonyl-1,4-dihydro-4-pyridyl)-6-(4-fluorophenyl)-2,3-dihydroimidazo[2,1-b]thiazole; m.p. 164°-166° (from acetone/hexane).

Provenance & Evidence