Hydrochloric Acid → (4S)-1-benzyloxycarbonyl-4-hydroxy-1,2,3,4-tetrahydroquinoline

Participants

Reaction Conditions

Reaction Steps

A mixture of 30.6 mg of [RuI2(p-cymene)]2, 73.3 mg of (S,S)-TsDPEN and 25 mL of isopropyl alcohol was heated in a nitrogen stream at 80° C. for 1 hour. The reaction solution was cooled to 25° C., and then to the reaction solution were added 281 mg of 1-benzyloxycarbonyl-4-oxo-1,2,3,4-tetrahydroquinoline, 28.1 mg of potassium hydroxide and 10 mL of isopropyl alcohol in series. The mixture was stirred at 25° C. for 23 hours. To the reaction solution was added 10 mL of 0.1N hydrochloric acid and the mixture was stirred, and then concentrated under reduced pressure, and to the residue was added 10 mL of ethyl acetate. The organic layer was separated, dried over magnesium sulfate, and then filtered. The filtrate was concentrated, and the resulting residue was purified by column chromatography on silica gel (solvent; hexan/ethyl acetate=4/1) to give 270 mg of (4S)-1-benzyloxycarbonyl-4-hydroxy-1,2,3,4-tetrahydroquinoline (optical purity: 99% ee, yield: 95%).

Provenance & Evidence