p-Toluenesulfonic acid → HCID 14685742, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 4-oxo-1-ethyl-8-hydroxymethyl-1,2,3,4-tetrahydroquinoline (3.80 g) in methanol (40 ml), molecular sieve 3A (4 g), cyclopropylamine (11.42 g) and p-toluenesulfonic acid (catalytic amount) were added and the mixture was stirred for 8 hours at 65° C. After ice-cooling the reaction mixture, molecular sieve 3A was filtered off, then sodium borohydride (1.05 g) was added thereto, and the mixture was stirred for 1 hour at room temperature. A small amount of water was added to the reaction mixture, and methanol was distilled off. The residue was extracted with dichloromethane and dried over anhydrous magnesium sulfate. The solvent was distilled off and the resulting residue was purified by silica gel column chromatography [eluent: n-hexane-ethyl acetate (3:1)]to give 4-cyclopropylamino-8-hydroxymethyl-1-ethyl-1,2,3,4-tetrahydroquinoline (3.69 g).

Provenance & Evidence