2-Chloropyridine → Ethyl 4,8-diethoxy-2-methylquinoline-6-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a nitrogen flushed vial were added ethyl 4-(acetylamino)-3-ethoxybenzoate (100 mg, 0.40 mmol), 2-chloropyridine (90 mg, 0.80 mmol) and CH2Cl2 (2 mL). Triflic anhydride (0.40 mmol) was added via a syringe at −78° C. The reaction mixture was stirred at −78° C. for 5 minutes. Ethyl ethynyl ether (0.174 mL, 40% in hexanes, 0.80 mmol) was added. The resulting reaction mixture was allowed to warm to room temperature and was stirred at room temperature for 1 hour. The reaction was quenched by addition of Na2CO3 (5 mL, sat'd.), water (20 mL) and EtOAc (20 mL). The layers were separated and the organic layer was dried over Na2SO4, filtered and concentrated. The crude product was purified on a silica gel column eluting with a gradient of 10-20% EtOAc/hexanes to give the title intermediate (10 mg) as a light brown sticky material.

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