2-Aminophenol → 4-[[4-[3-(2-benzoxazolyl)propoxy]phenyl]sulfonyl]tetrahydro-N-hydroxy-2H-pyran-4-carboxamide

Participants

Reaction Conditions

Reaction Steps

Part A. To a solution of 4-[[4-(3-carboxypropoxy)phenyl]sulfonyl]tetrahydro-2H-pyran-4-carboxylic acid, 1,1-dimethylethyl ester (3.0 g, 7.0 mmol) in N,N-dimethylformamide (14 mL) was added 1-(3-dimethylamino-propyl)-3-ethylcarbodiimide hydrochloride (1.88 g, 9.8 mmol) and 1-hydroxybenzotriazole (1.32 g, 9.8 mmol). The resulting suspension became a clear amber solution after stirring at 50° C. for 1.5 hr. The reaction was then treated with 2-aminophenol (0.76 g, 7.0 mmol), followed by N-methylmorpholine (2.3 mL, 21.0 mmol). The reaction was stirred at 50° C. overnight. After 21 hr, the reaction was partitioned between ethyl acetate (50 mL) and water (50 mL). The aqueous layer was extracted with ethyl acetate. The organic layers were combined and washed with saturated sodium bicarbonate solution, water, 1:1 solution of water:brine, and brine; dried over sodium sulfate; filtered; and concentrated in vacuo. The resulting oil was purified on silica gel using ethyl acetate/hexanes to afford 2.98 g (82%) of the amide as an amber oil. ESMS m/z=542 [M+Na]+.

Provenance & Evidence