Thionyl Chloride → 3-(1-Chloroethyl)-5,6,7,8-tetrahydroisoquinoline

Participants

Reaction Conditions

Reaction Steps

3-(1-Hydroxyethyl)-5,6,7,8-tetrahydroisoquinoline (360 mg, 2.0 mmole) was dissolved in 4 ml dichloromethane in a 25 ml one neck round bottom flask under nitrogen. The solution is cooled to 0° C., is treated dropwise with thionyl chloride (218 μl, 3.0 mmole) in 3 ml dichloromethane, and is stirred 2 h at 0° C. followed by 1.5 h at room temperature. The mixture is recooled to 0° C., is quenched with 20 ml saturated sodium bicarbonate, and the layers are separated. The aqueous layer is extracted with 4×10 ml dichloromethane and the combined organics are dried over potassium carbonate. The dried organics are concentrated in vacuo to an amber oil. The crude material is chromatographed over 30 g silica gel (230-400 mesh), eluting with 20% acetone/hexane, while collecting 5 ml fractions. Fractions 11-16 are combined and concentrated to afford 339 mg (87%) of 3-(1-chloroethyl)-5,6,7,8-tetrahydroisoquinoline.

Provenance & Evidence