Diisopropylethylamine → tert-butyl 2-(2-(3-azidopropyl)-5-(2,5-difluorophenyl)-2-phenyl-1,3,4-thiadiazol-3(2H)-yl)-6,7-dihydrothiazolo[5,4-c]pyridine-5(4H)-carboxylate

Participants

Reaction Steps

To a solution of 2-(3-azidopropyl)-5-(2,5-difluorophenyl)-2-phenyl-1,3,4-thiadiazole-3(2H)-carbothioamide (0.300 g, 0.717 mmol) in 10 mL of ethanol was added tert-butyl 3-bromo-4-oxopiperidine-1-carboxylate (0.239 g, 0.860 mmol) followed by DIEA (0.25 mL, 1.43 mmol). The mixture was allowed to stir overnight at reflux, then treated with tert-butyl 3-bromo-4-oxopiperidine-1-carboxylate (100 mg) and stirred at reflux for a further 3 hours. The cooled mixture was partitioned between a saturated NaHCO3 solution (30 mL) and EtOAc (30 mL), and the aqueous layer was extracted with EtOAc (2×20 mL). The combined organic phases were washed with brine (20 mL), dried over Na2SO4, and concentrated in vacuo. The residue was purified by flash column chromatography (5-10% ethyl acetate/hexanes) to afford the desired product as a bright yellow foam, 0.313 g, 73%.

Provenance & Evidence