35.2% |
With O-(1H-benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate; N-ethyl-N,N-diisopropylamine In N,N-dimethyl-formamide at 22℃; for 18h; |
50 Example 50: N-(benzo[c][l,2,5]thiadiazol-4-yl)-6-bromobenzo[d][l,3]dioxole-5- carboxamide:
6-bromo-l,3-benzodioxide-5-carboxylic acid (0.0352 g, 0.1436 mmol), 2,1,3- henzothi adi azol -4-amine (0.0265 g, 0.1753 mmol) and (2-(lH-benzotriazol-l-yl)-l, 1,3,3- tetramethyluronium hexafluorophosphate) (HBTU, 0.0622 g, 0.1640 mmol) were dissolved in N,N- dimethylformamide (DMF, 1 mL) and treated with /V,/V-di isopropyl ethyl amine (0.03 mL). The mixture was stirred at 22 °C for 18 hours. Ethyl acetate (20 mL) was added to dilute the mixture and washed with HC1 (5 mL, 1M, twice), saturated NaHCCE solution, and saturated brine, subsequently, and concentrated under vacuum, and purified using normal phase chromatography (4 g Isco silica column, Ethyl acetate-Hexane, 0-20%) gave a yellow solid (0.0191 g, 35.2%). ' H NMR (300 MHz, CDCT): S 9.17 (s, 1H), 8.63 (d, / = 6 Hz, 1H), 7.75-7.63 (m, 2H), 7.11 (s, 1H), 6.09 (s, 2H, OCH2O). Calculated MS for CwHsBrNsCbS, 376.95; observed, (M + H)+ 378.3. |