Sodium Carbonate → Methyl 4-(4-{[(4-tert-Butylphenyl)sulfonyl]methyl}-5-methyl-1,3-oxazol-2-yl)benzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of Na2SO3 (126 mg, 1.0 mmol) and Na2CO3 (106 mg, 1.0 mmol) in water (2 mL) was added to a suspension of 4-tert-butylbenzenesulfonyl chloride (233 mg, 1.0 mmol) in water (5 mL) and the mixture was stirred at 100° C. for 2 h. A solution of chloride 2 (268 mg, 1.0 mmol) in EtOH (5 mL) was added and the mixture stirred at 100° C. for 16 h. The mixture was cooled and diluted with water (40 mL) and stirred for 15 min. The precipitate was filtered, washed with water (5 mL). The residue purified by column chromatography, eluting with a gradient (20-50%) of EtOAc/pet. ether, to give benzoate 22 (112 mg, 26%) as a white powder: mp (EtOAc) 190-192° C.; 1H NMR (CDCl3) δ 8.05 (ddd, J=8.6, 1.8, 1.5 Hz, 2H, H-2, H-6), 7.89 (ddd, J=8.6, 1.8, 1.5 Hz, 2H, H-3, H-5), 7.71 (ddd, J=8.6, 2.2, 1.8 Hz, 2H, H-2′, H-6′), 7.51 (ddd, J=8.6, 2.2, 1.8 Hz, 2H, H-3′, H-5′), 4.30 (s, 2H, CH2SO2), 3.94 (s, 3H, OCH3), 2.32 (s, 3H, CH3), 1.33 [s, 9H, C(CH3)3]; MS m/z 428.5 (MH+, 100%). Anal. calcd for C23H25NO5S: C, 64.62; H, 5.89; N, 3.28. Found: C, 64.70; H, 5.94; N, 3.25%.

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