反应详情

温度

8 °C

Into a 1 liter three-neck flask was introduced 40 g (0.19 mole) of 3-amino-2,4-dichlorobenzoic acid and 150 ml of tetrahydrofuran. The solution was cooled to 8°-10° C. in an ice bath. A borontrifluoride-tetrahydrofuran (1M) solution (280 ml) was added dropwise over a period of 1 hr. After being stirred at 8° C. for an additional 1 hr. the solution was allowed to warm up slowly to room temperature. The reaction flask was then cooled again in an ice bath and 50 ml of water was added through a dropping funnel. The mixture was taken into 1 liter of methylene chloride and washed once with NaHCO3 and twice with water, then dried over calcium sulfate. The methylene chloride solution afforded 19.2 g of crude solid product, mp 111-121. Five grams of the crude solid was recrystallized from acetonitrile to yield 4.2 g of 3-amino-2,5-dichlorobenzyl alcohol; mp 121-127; nmr (DMSO-d6) δ4.50 (D, 2H), 5.34 (t, 1H), 5.52 (S, 2H), 6.73 (S, 2H); ir (CHCl3) 3490, 3380, 3240, 1630 and 1598 Cm-1.

1. temperatureThe solution was cooled to 8°-10° C. in an ice bath
2. temperatureto warm up slowly to room temperature
3. temperatureThe reaction flask was then cooled again in an ice bath
4. washwashed once with NaHCO3 and twice with water
5. dry with materialdried over calcium sulfate
6. customThe methylene chloride solution afforded 19.2 g of crude solid product, mp 111-121
7. customFive grams of the crude solid was recrystallized from acetonitrile