Potassium Carbonate → tert-Butyl (2S,4S)-4-[(6-bromo-1-oxo-1,2-dihydroisoquinolin-4-yl)sulfanyl]-2-({[tert-butyl(diphenyl)silyl]oxy}methyl)piperidine-1-carboxylate

Participants

Reaction Steps

Sodium borohydride (97 mg) was added to a degassed solution of 6-bromo-4-sulfanylisoquinolin-1(2H)-one (Example 58a, 0.54 g) in ethanol (20 mL) at room temperature with effervescence. The resulting mixture was stirred at room temperature for 10 min before being heating to 85° C. A degassed solution of tert-Butyl (2S,4R)-2-({[tert-butyl(diphenyl)silyl]oxy}methyl)-4-[(methylsulfonyl)-oxy]piperidine-1-carboxylate (Example 67d, 1.17 g) in ethanol (3 mL) and potassium carbonate (0.353 g) were added to the orange solution and the reaction was heated for 1 h, cooled to room temperature and concentrated in vacuo. Purification (SiO2 chromatography, elution gradient 25% to 40% ethyl acetate in isohexane) afforded the subtitle product (0.68 g) as a white foam.

Provenance & Evidence