Hydrochloric Acid → tert-butyl (2S)-2-[(1-cyclohexyl-3,4-dihydroisoquinolin-2(1H)-yl)carbonyl]pyrrolidine-1-carboxylate

Participants

Reaction Steps

N-methylmorpholine (0.873 mL) was added to a solution of 1-(tert-butoxycarbonyl)-L-proline (1.28 g) in 1,2-dichloroethane (10 mL) under ice-cooling, followed by further addition of pivaloyl chloride (0.734 mL). The reaction liquid was stirred for 1 hour, and N-methylmorpholine (1.09 mL) and 1-cyclohexyl-1,2,3,4-tetrahydroisoquinoline hydrochloride (1.00 g) were then added thereto. The mixture was stirred at room temperature for 15 hours. To the reaction solution were added EtOAc and an aqueous 1 M HCl solution. The organic layer was washed with water, a saturated aqueous sodium hydrogen carbonate solution, and saturated brine, dried over magnesium sulfate, and filtered. The filtrate was concentrated under reduced pressure to obtain tert-butyl (2S)-2-[(1-cyclohexyl-3,4-dihydroisoquinolin-2(1H)-yl)carbonyl]pyrrolidine-1-carboxylate (1.79 g).

Provenance & Evidence