反应详情

温度

0 °C

An oven-dried, 500-milliliter, 3-necked, round-bottomed flask was charged with 5 grams (27.4 millimole) of 4-acetyl-3-fluorophenyl boronic acid and 25 milliliters of methanol under a nitrogen atmosphere. The solution was cooled to 0° C. using an ice bath. To this solution was added 0.2 milliliters (0.55 equivalents) of glacial acetic acid. In a 100 milliliters Erlenmeyer flask was taken 1.27 milliliters (3.95 grams, 24 millimole, 0.9 equivalents) of elemental bromine dissolved in 4 milliliters of cold methanol. The bromine solution was added dropwise to the above solution at 0° C. using an addition funnel. With the addition of Br2, the solution slowly turned light orange and finally to dark orange when addition was complete. After about 5-6 hours, the progress of the reaction was monitored by NMR. Depending on the progress of reaction, another 10-20 mole % of bromine was added after cooling the solution to 0° C. Total reaction time was approximately 24 hours.

1. additionthe solution slowly turned light orange and finally to dark orange when addition
2. customDepending on the progress of reaction
3. temperatureafter cooling the solution to 0° C
4. waitTotal reaction time was approximately 24 hours