反应详情

温度

-78 °C

A stirred mixture of 6-bromo-2,3-dihydro-benzo[1,4]dioxine (1.66 g, 7.7 mmol) and dry THF (20 mL) was cooled to −78° C., evacuated and refilled with nitrogen for 10 cycles. To this clear solution was slowly added n-butyllithium (2.9 mL, 7.4 mmol) and stirred for 20 min. Then a mixture of 4-methoxy-benzaldehyde (0.90 g, 6.6 mmol) in dry THF (10 mL) was added and stirred for 1 hour at −78° C. The mixture was quenched with isopropanol (3.4 mL, 44 mmol) and added water (10 mL). The mixture was extracted with EtOAc (3×30 mL). The combined organic phases were washed with water (2×30 mL), dried over MgSO4 and concentrated to give (2,3-dihydro-benzo[1,4]dioxin-6-yl)-(4-methoxy-phenyl)-methanol as an oil (2.04 g, 102% crude yield). The product was used in the next step without further purification.

1. customevacuated
2. additionrefilled with nitrogen for 10 cycles
3. additionwas added
4. stirringstirred for 1 hour at −78° C
5. extractionThe mixture was extracted with EtOAc (3×30 mL)
6. washThe combined organic phases were washed with water (2×30 mL)
7. dry with materialdried over MgSO4
8. concentrationconcentrated