Hydrochloric Acid → 6-Iodoisoquinoline-1,3(2h,4h)-dione

Participants

Reaction Steps

An amount of 6-bromo-1,3-bis{[tert-butyl(dimethyl)silyl]oxy}isoquinoline (15.0 g, 32.0 mmol) in 100 mL of anhydrous tetrahydrofuran is cooled to −78° C. and then 47 mL (80.0 mmol) of tert-butyllithium (1.7 M in pentane) is added slowly with stirring. After stirring at this temperature for 2 hr, 12.0 g (48 mmol) of fresh iodine crystal is quickly add into the mixture, and stirred at this temperature for additional 5 h. The dry-ice bath is removed, and the reaction mixture is allowed to warm up to room temperature and stirred over weekend. Evaporating the brown solution yielded brown oil. The reaction mixture is acidified with 48 mL of 2 M HCl solution and stirred at room temperature for 1 h. The mixture is filtered to give light tan solid. The solid is dissolved in hot DMSO, then 20% MeOH/H2O solution is added to give a precipitate. The precipitate is collected and washed successively with water, methanol, ether and hexane to afford 5.1 g (55.6% yield) of off-white solid: MS (ESI) m/z 286.08 (M−H)−1

Provenance & Evidence