反应详情

A solution of 3-(4-chloro-benzyloxy)-4-(4-methoxy-benzyloxy)-benzaldehyde (41)(108 g) in acetic acid (500 mL) was heated at reflux overnight. Excess acetic acid was removed by rotary evaporation under reduced pressure (hard vacuum) and the resulting residue taken up in ethyl acetate. The organic layer was extracted with aqueous sodium hydroxide solution (1 N; 3×150 mL). The combined inorganic phases were neutralised with conc. hydrochloric acid and back extracted with ethyl acetate. The organic layer was washed with brine and dried over magnesium sulphate. The resulting oil was triturated with 50/50 diethyl ether/hexane, the solid product 42 collected by vacuum filtration and the precipitate washed with hexane (32.6 g, 44%, retention time 3.08 mins, ES− 261.33).

1. temperatureat reflux overnight
2. customExcess acetic acid was removed by rotary evaporation under reduced pressure (hard vacuum)
3. extractionThe organic layer was extracted with aqueous sodium hydroxide solution (1 N; 3×150 mL)
4. extractionback extracted with ethyl acetate
5. washThe organic layer was washed with brine
6. dry with materialdried over magnesium sulphate
7. customThe resulting oil was triturated with 50/50 diethyl ether/hexane
8. filtrationthe solid product 42 collected by vacuum filtration
9. washthe precipitate washed with hexane (32.6 g, 44%, retention time 3.08 mins, ES− 261.33)