反应详情

A solution of benzoquinone (23.5 grams, 217 mmol) in ethanol (500 mL) was added at room temperature over 30 minutes to a solution of 4-fluoro-benzenesulfinic acid (34.8 grams, 217 mmol) in a mixture of ethanol (300 mL) and water (500 mL). The resulting solution was stirred for 2 hours at room temperature then diluted to 4L with warm water. The solution was kept at 4° C. for 62 hours and crystals formed. The crystalline solid was collected by filtration and washed with water (3 times 500 ml) and hexanes (2 times 500 ml) and dried to give the title compound of Step B (40.8 grams). 1H NMR (400 MHz, CDCl3) δ8.64 (bs, 1H), 7.96-7.92 (m, 2H), 7.22-7.16 (m, 2H), 7.08 (d, 1H), 6.97 (dd, 1H), 6.89 (d, 1H). MS (APCI−) Calc.: 268.0, Found: 267.1 (M−1).

1. waitThe solution was kept at 4° C. for 62 hours
2. customcrystals formed
3. filtrationThe crystalline solid was collected by filtration
4. washwashed with water (3 times 500 ml) and hexanes (2 times 500 ml)
5. customdried