反应详情

温度

20 °C

α-Methyl-2,3-dichlorobenzyl alcohol (5.0 g, 0.026 mol was dissolved in acetic acid (24 ml) and 12% w/v sodium hypochlorite solution (23.26 ml, 0.0314 mol) was added slowly dropwise, with stirring, at a temperature of 15-25° C. When the addition was complete the reaction mixture was stirred at ambient temperature for approximately 11/2 hours until a starch/iodide test gave a positive result. Saturated sodium bisulphite solution was added to the reaction mixture until the starch/iodide test was negative. The mixture was poured onto ice/brine (100 ml) and extracted with diethyl ether (3×75 ml). The ether phases were combined and washed with 2N sodium hydroxide solution (3×75 ml) until the aqueous washes were alkaline. The ether phase was dried over anhydrous magnesium sulphate, filtered and evaporated down. 2,3-Dichloroacetophenone (3.2 g, 65% yield) was afforded as a pale-yellow oil. T.l.c. (SiO2 ;CHCl3) and nmr showed this material to contain no impurities.

1. additionwas added slowly dropwise
2. additionWhen the addition
3. customgave a positive result
4. additionThe mixture was poured onto ice/brine (100 ml)
5. extractionextracted with diethyl ether (3×75 ml)
6. washwashed with 2N sodium hydroxide solution (3×75 ml) until the aqueous washes
7. dry with materialThe ether phase was dried over anhydrous magnesium sulphate
8. filtrationfiltered
9. customevaporated down