Potassium Carbonate → tert-Butyl 4-[(6-bromo-1-oxo-1,2-dihydroisoquinolin-4-yl)sulfanyl]piperidine-1-carboxylate

Participants

Reaction Steps

To 6-bromo-4-sulfanylisoquinolin-1(2H)-one (Example 58a, 0.62 g) was added tert-butyl 4-[(methylsulfonyl)oxy]piperidine-1-carboxylate (0.676 g) and potassium carbonate (0.769 g). After thoroughly flushing with nitrogen, DMF (6 mL) was added and the reaction stirred at room temperature for 30 min. Further DMF (9 mL) was added, and the reaction stirred at 40° C. for 1 h. Further DMF (10 mL) was added and the reaction stirred at 50° C. for 16 h. The reaction was partitioned between ethyl acetate and water. The aqueous was extracted with further ethyl acetate (3×) and the combined organics were washed with saturated brine (3×100 mL). The organics were dried (MgSO4), filtered and evaporated under reduced pressure. DCM was added, and the resulting suspension was filtered. The filtrate was concentrated under reduced pressure, dissolved in the minimum volume of DCM and purified (SiO2 chromatography, elution with 50%-100% diethyl ether/isohexane followed by ethyl acetate flush) to afford the subtitle compound (0.353 g).

Provenance & Evidence