Chlorosulfonic acid → 2-Acetyl-1,2,3,4-tetrahydroisoquinoline-7-sulfonyl chloride

Participants

Reaction Conditions

Reaction Steps

To a solution of 140 g. (0.8 mole) 2-acetyl-1,2,3,4-tetrahydroisoquinoline in 150 ml. dry methylene chloride at -15° C. with sufficient stirring was added dropwise 300 ml. (4.5 mole) chlorosulfonic acid. After the addition of the chlorosulfonic acid was complete, the reaction mixture was stirred for one hour at -15° C. and then heated to reflux for 2 hours. The reaction mixture was then cooled to 10° C. and then cautiously poured onto 3 l. of ice. The crude reaction product was then extracted in methylene chloride (2×150 ml.), dried over anhydrous magnesium sulfate and filtered. The filtrate was concentrated to dryness at reduced pressure to afford 2-acetyl-7-chlorosulfonyl-1,2,3,4,-tetrahydroisoquinoline as a viscous yellow oil.

Provenance & Evidence