2,6-Lutidine → (2R)-N-cyclopropyl-N-{(1R)-1-[4-(3-methoxypropoxy)-1-benzofuran-6-yl]ethyl}morpholine-2-carboxamide

Participants

Reaction Steps

To a solution of tert-butyl (2R)-2-[(cyclopropyl{1-[4-(3-methoxypropoxy)-1-benzofuran-6-yl]ethyl}amino)carbonyl]morpholine-4-carboxylate (200 mg) and 2,6-lutidine (0.142 mL) in chloroform (4 mL) was added trimethylsilyltriflate (0.180 mL) under ice-cooling, and the mixture was stirred at the same temperature for 30 minutes. Then, thereto was added aqueous saturated sodium hydrogen carbonate solution under ice-cooling, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated saline, dried over magnesium sulfate, and then concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: chloroform/methanol/ammonia water=200/2/1) to give (2R)-N-cyclopropyl-N-{(1R)-1-[4-(3-methoxypropoxy)-1-benzofuran-6-yl]ethyl}morpholine-2-carboxamide [Ex(1-1)] (12.5 mg) and (2R)-N-cyclopropyl-N-{(1S)-1-[4-(3-methoxypropoxy)-1-benzofuran-6-yl]ethyl}morpholine-2-carboxamide [Ex(1-2)] (20.2 mg) as a colorless oil.

Provenance & Evidence