Benzyl 4-(chlorocarbonyl)piperidine-1-carboxylate → Benzyl-4-(3-hydroxy-6-methoxy-2-methyl-1-oxo-4-phenyl-1,2,3,4-tetra-hydroisoquinolin-3-yl)piperidine-1-carboxylate

Participants

Reaction Steps

To an isopropanol/dry ice cooled solution of 4-Methoxy-N-methyl-2-(phenylmethyl)benzamide (250 mg, 0.980 mmol) in THF (50 mL) under argon was added sec-butyllithium solution (1.3M, 1.55 mL, 2.00 mmol) dropwise. After 10 min. a THF (10 mL) solution of benzyl-4-(chlorocarbonyl)piperidine-1-carboxylate (275 mg, 980 mmol) was quickly added to the reaction solution. After 10 min. the reaction was quenched with water then warmed to room temperature. Saturated sodium bicarbonate was added and the resulting mixture extracted with ethyl acetate (3×) and dried with anhydrous magnesium sulfate. Filtration followed by evaporation of solvent in vacuo gave the crude product which was subjected to flash column chromatography (hexane:ethyl acetate 50:50) to afford benzyl-4-(3-hydroxy-6-methoxy-2-methyl-1-oxo-4-phenyl-1,2,3,4-tetra-hydroisoquinolin-3-yl)piperidine-1-carboxylate as a white foam (242 mg, 0.484 mmol, 49%). MS [M+H]+ 501.2

Provenance & Evidence