反应详情

A solution of bromine (18 ml) in chloroform (80 ml) was added dropwise at 10°-15° C. over 1.5 hours to a stirred solution of the above 1-[1-(3,4-dichlorophenyl)-cyclobutyl]ethanone (89.6 g) in a mixture of methanol (120 ml) and chloroform (20 ml). When the addition was complete, the mixture was stirred at ambient temperature for 1 hour, then poured onto an excess of ice-water. The aqueous layer was separated and the product extracted into dichloromethane (2×150 ml). The combined organic solutions were washed with saturated aqueous sodium hydrogen carbonate solution (2×200 ml) then with water, dried over calcium chloride and the solvent removed in vacuo to yield an oil. The oil was distilled to give 2-bromo-l-[1-(3,4-dichlorophenyl)-cyclobutyl]ethanone (88.31 g), b.p. 148°-154° C./0.66 mbar.

1. additionWhen the addition
2. customThe aqueous layer was separated
3. extractionthe product extracted into dichloromethane (2×150 ml)
4. washThe combined organic solutions were washed with saturated aqueous sodium hydrogen carbonate solution (2×200 ml)
5. dry with materialwith water, dried over calcium chloride
6. customthe solvent removed in vacuo
7. customto yield an oil
8. distillationThe oil was distilled