Diisopropylethylamine → HCID 66788954, compound

Participants

Reaction Steps

3,4-Dihydro-2H-quinoxaline-1,6-dicarboxylic acid 1-tert-butyl ester 6-ethyl ester (300 mg, 0.98 mmol) was dissolved in dichloromethane (20 mL) and pyridine (2 mL). N,N-Diisopropylethylamine (127 mg, 0.98 mmol) and 5-chloro-2-methoxy-benzensulfonyl chloride (300 mg, 1.24 mmol) were added, and the mixture was stirred at room temperature overnight. The solvent was evaporated, and the crude compound was purified by flash chromatography, yielding 4-(5-chloro-2-methoxy-benzenesulfonyl)-3,4-dihydro-2H-quinoxaline-1,6-dicarboxylic acid 1-tert-butyl ester 6-ethyl ester as a light yellow gum, 435 mg (87%), δH (300 MHz; CDCl3) 8.17 (1H, s), 8.05 (1H, s), 7.82 (1H, d), 7.74 (1H, d), 7.46 (1H, dd), 6.82 (1H, d), 4.35 (2H, q), 3.93 (2H, m), 3.71 (2H, m), 3.56 (3H, s), 1.48 (9H, s), 1.39 (3H, t).

Provenance & Evidence