反应详情

温度

-10 °C

To a solution of ethyl magnesium bromide prepared from 3.9 g. of magnesium turnings and 17.4 g. of ethyl bromide in 50 ml. of dry ether a solution of 9.3 g. of 4-chloro-4'-hydroxy-benzophenone in 40 ml. of dry ether is added dropwise, with stirring at -10° C., in nitrogen atmosphere. The reaction mixture is allowed to warm up to room temperature, stirred at this temperature for an additional half an hour, and is then poured onto a solution of ammonium chloride in ice water under cooling. The aqueous phase is extracted with ether, the ethereal phases are combined, washed to neutral with water, and dried over anhydrous magnesium sulfate. After filtering the solvent is distilled off in vacuo, the residue is decolored with charcoal in methanol, the solution is filtered, and the solvent is evaporated under reduced pressure. The crude mixture is crystallized from a mixture of benzene and ethyl acetate to yield 5.5 g. of the named compound, melting at 148° to 149° C.

1. temperatureto warm up to room temperature
2. stirringstirred at this temperature for an additional half an hour
3. temperatureunder cooling
4. extractionThe aqueous phase is extracted with ether
5. washwashed to neutral with water
6. dry with materialdried over anhydrous magnesium sulfate
7. filtrationAfter filtering the solvent
8. distillationis distilled off in vacuo
9. filtrationthe solution is filtered
10. customthe solvent is evaporated under reduced pressure
11. customThe crude mixture is crystallized from a mixture of benzene and ethyl acetate
12. customto yield 5.5 g