Acetic Acid → 5-Methanesulfonyloxy-1,2,3,4-tetrahydroquinoline

Participants

Reaction Steps

4.5 g of 5-methanesulfonyloxy-3,4-dihydrocarbostyril was suspended in 90 ml of dioxane and 35 g of NaBH4 was added to the suspension then 5.3 ml of acetic acid was added dropwise to the mixture. After heat-refluxing the resulting mixture for 1 hour the solvent was removed under reduced pressure. A saturated aqueous solution of sodium bicarbonate was added to the residue to form precipitates which were filtered and washed with chloroform. The filtrate was extracted with chloroform and the chloroform layer was dried over Na2SO4 followed by removing the solvent. The residue was purified through a silica gel column chromatography (silica gel: Wako C-200, a trade name for a product of Wako Junyaku Co., Ltd.; eluent: chloroform) and the eluate thus-obtained was crystallized from petroleum ether. Recrystallization of the crystals thus-obtained from methanol gave 1.9 g of 5-methanesulfonyloxy-1,2,3,4-tetrahydroquinoline, colorless prisms having a melting point of 74° to 76° C.

Provenance & Evidence