反应详情

A solution of the product of step (b) (16.04 g) in a mixture of ethanol (100 ml) and water (25 ml) was treated with precipitated calcium carbonate (13.37 g) and the mixture refluxed for 20 hours. After cooling, the mixture was filtered, the filtrate stripped, and the residue taken up in 2 M aqu. HCl (100 ml) and extracted with ether (200 ml). The extract was washed with water (100 ml), dried over Na2SO4 and stripped to give a pale yellow oil which was distilled under reduced pressure to give the desired product (8.90 g), bp 100°-130° C./0.2 mm Hg.

1. temperaturethe mixture refluxed for 20 hours
2. temperatureAfter cooling
3. filtrationthe mixture was filtered
4. extractionHCl (100 ml) and extracted with ether (200 ml)
5. washThe extract was washed with water (100 ml)
6. dry with materialdried over Na2SO4
7. customto give a pale yellow oil which
8. distillationwas distilled under reduced pressure