反应详情

温度

-30 °C

Into a 20 L 4-necked round-bottom flask purged and maintained with an inert atmosphere of nitrogen was placed a solution of 9-Bromo-2-iodo-4,5-dihydro-6-oxa-1,3a-diaza-benzo[e]azulene (700 g, 1.79 mol, 1.00 equiv) in tetrahydrofuran (13 L), followed by the addition of EtMgBr (1400 mL) dropwise with stirring at −30° C. over 60 min. To the above an excess of CO2 (gas) was introduced in over 3 h at −78° C. The resulting solution was warmed to room temperature naturally. The pH value of the solution was adjusted to 3 with hydrogen chloride (2 mol/L). The precipitates were collected by filtration, washed with 2×100 mL of EA and dried in a vacuum oven to afford 410 g (74%) of 9-Bromo-4,5-dihydro-6-oxa-1,3a-diaza-benzo[e]azulene-2-carboxylic acid as a white solid.

1. customInto a 20 L 4-necked round-bottom flask purged
2. temperaturemaintained with an inert atmosphere of nitrogen
3. temperatureThe resulting solution was warmed to room temperature naturally
4. filtrationThe precipitates were collected by filtration
5. washwashed with 2×100 mL of EA
6. customdried in a vacuum oven