4-Methylmorpholine → 2-Chloro-4-{[3-(5-chloro-2-methoxy-benzenesulfonyl)-2,3-dihydro-benzooxazole-5-carbonyl]-amino}-benzoic acid ethyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 3-(5-chloro-2-methoxy-benzenesulfonyl)-2,3-dihydro-benzooxazole-5-carboxylic acid (1.00 g, 2.70 mmol), ethyl 4-amino-2-chlorobenzoate (1.08 g, 5.41 mmol), 4-methylmorpholine (1.37 g, 13.5 mmol), and O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyl-uronium hexafluoro-phosphate (1.54 g, 4.06 mmol) in N,N-dimethylformamide (10 mL) was stirred at room temperature for 15 min, then 4-(dimethylamino)pyridine (337 mg, 2.70 mmol) were added, and the solution was stirred at 60° C. for 18 h. After cooling, the reaction mixture was partitioned between water, heptane, and ethyl acetate. The organic layer was washed with brine, dried (MgSO4), and evaporated. Chromatography (SiO2, heptane-ethyl acetate gradient) produced 2-chloro-4-{[3-(5-chloro-2-methoxy-benzenesulfonyl)-2,3-dihydro-benzooxazole-5-carbonyl]-amino}-benzoic acid ethyl ester (849 mg, 57%). Off-white solid, MS (ISP)=551.2 (M+H)+.

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