Ethyl 4-chloro-6-methoxyquinoline-3-carboxylate → 6-Methoxy-3-ethoxycarbonyl-1,2,3,4-tetrahydroquinoline

Participants

Reaction Steps

To a suspension of 6-methoxy-4-chloro-3-ethoxycarbonyl-quinoline (Step B, 20 g, 0.075 mol) in 1/1 EtOAc/AcOH (560 mL) in a Parr hydrogenation apparatus bottle kept under inert atmosphere was added Pt/C 10% (2 g). The mixture was hydrogenated under 60 psi hydrogen at RT for 2 h using a Parr hydrogenation apparatus. The resulting mixture was diluted with MeOH and filtered. The solid was washed several times with a 1/1 MeOH/CH2Cl2 mixture and the solvents were removed under vacuum. The resulting solid was suspended into CH2Cl2 and 2N NaOH was added. The mixture was stirred at RT for 30 min. The organic layer was recovered and washed once with 2 N NaOH and twice with water to give crude 6-methoxy-3-ethoxycarbonyl-1,2,3,4-tetrahydroquinoline, which was directly used in the next step.

Provenance & Evidence