Hydrogen Bromide → (S)-2-methyl-1,2,3,4-tetrahydroquinolin-5-ol hydrobromide

Participants

Reaction Conditions

Reaction Steps

A 500-mL round bottomed flask equipped with a heating mantle and an overhead stirrer was charged with (S)-5-methoxy-2-methyl-1,2,3,4-tetrahydroquinoline hydrochloride (20 g, 94 mmol) followed by hydrobromic acid (48%, 154 mL, 1361 mmol). The mixture was heated to 100° C., and the reaction readily proceeded with loss of bromomethane through an uncooled reflux condenser. After 1 h, solids precipitated from the solution. The reaction was complete after 10 h at 100° C. and allowed to cool to ambient temperature while stirring overnight. The reaction mixture was placed in an ice bath and stirred for 2 h at 0-5° C. The resulting white slurry was filtered and the pot and solids were washed with 20 mL of ice cold water. The filter cake was dried on a Buchner funnel under nitrogen blanket to afford (S)-2-methyl-1,2,3,4-tetrahydroquinolin-5-ol hydrobromide (21.71 g, 95%) as a white powder. MS (ES, m/z): 164 [M+H]+

Provenance & Evidence