[Br:1][CH:2]([CH2:14]Br)[CH2:3][CH:4]([C:6]1[CH:11]=[CH:10][C:9]([F:12])=[CH:8][C:7]=1[F:13])[OH:5].[OH-].[Ca+2].[OH-].[Br-].[Ca+2].[Br-].O>C(OCC)(=O)C.CO>[Br:1][CH:2]1[CH2:14][O:5][CH:4]([C:6]2[CH:11]=[CH:10][C:9]([F:12])=[CH:8][C:7]=2[F:13])[CH2:3]1
A mixture of 4.5 g of product from Example 164, 1.67 g of calcium hydroxide, 7.5 g of calcium bromide, 25 ml of water and 12 ml of methyl alcohol is stirred and heated at 85° C. overnight. The reaction mixture is cooled, diluted with ethyl acetate and filtered through diatomaceous earth. The layers are separated and the organic layer is washed with saturated sodium chloride, dried, filtered and concentrated in vacuo. The residue is purified by chromatography (silica gel: 3-5% ethyl acetate/hexane) to give 1.96 g of the desired product as a mixture of isomers.
Wird geladen…
