反应详情

To a solution of potassium hydroxide (3.5 g) in ethanol (50 mL) at 0° C. was added dropwise the ethyl ester of 3-(difluoromethyl)-1H-pyrazole-4-carboxylic acid (10.1 g) in ethanol (50 mL), followed by dropwise addition of allyl bromide (4.6 mL). The mixture was stirred overnight, partitioned between ether and 2N HCl. The ether layer was dried (MgSO4) and concentrated in vacuo leaving an oil (11.4 g). The oil was distilled (Kugelrohr 80-85 ° C., 0.3 mm) to give the isomer of the desired product as an oil (2.6 g). Distillation was continued (100-105 ° C., 0.3 mm) to give the desired compound as a clear colorless oil (8.0 g).

1. custompartitioned between ether and 2N HCl
2. dry with materialThe ether layer was dried (MgSO4)
3. concentrationconcentrated in vacuo