反应详情

温度

0 °C

Alternatively, reaction of 11 with 2-aminoethanol and potassium tert-butoxide displaces fluorine to give 2-(2-aminoethoxy)-4-bromobenzonitrile hydrochloride 37. Ring closure of 37 with trimethylaluminum gave 33 (Scheme 14). A solution of 11 (10 g, 50 mmol) and 2-aminoethanol (3.1 mL, 50.8 mmol) in 2-methyltetrahydrofuran (80 mL) was cooled to 0° C. and a solution of 1M potassium tert-butoxide in tetrahydrofuran (55 mL, 55 mmol) was slowly added while maintaining the solution temperature below 5° C. The reaction was stirred at 0° C. for 30 min until judged complete by HPLC at which point it was warmed to 25° C. A solution of 0.5M HCl in isopropanol (100 mL, 50 mmol) was added and the desired HCl salt 3 crystallized directly from the solution. The solid was collected by filtration and dried under vacuum with a nitrogen bleed to give 2-(2-aminoethoxy)-4-bromobenzonitrile hydrochloride 37 as a white solid. (12.1 g, 87% yield).

1. temperaturewhile maintaining the solution temperature below 5° C
2. temperaturewas warmed to 25° C
3. customthe desired HCl salt 3 crystallized directly from the solution
4. filtrationThe solid was collected by filtration
5. customdried under vacuum with a nitrogen