[F:1][C:2]1[CH:19]=[CH:18][C:5]([C:6]([C:11]2[CH:16]=[CH:15][C:14]([F:17])=[CH:13][CH:12]=2)([OH:10])[C:7]([OH:9])=[O:8])=[CH:4][CH:3]=1.[O-][CH2:21]C.[Na+].[Na].CI>C(O)C>[F:1][C:2]1[CH:19]=[CH:18][C:5]([C:6]([C:11]2[CH:16]=[CH:15][C:14]([F:17])=[CH:13][CH:12]=2)([OH:10])[C:7]([O:9][CH3:21])=[O:8])=[CH:4][CH:3]=125.0 g (0.095 mol) of 4,4′-difluorobenzilic acid are added to freshly prepared sodium ethoxide solution containing 2.17 g (0.095 mol) of sodium and 200 ml of ethanol at 20° C. and stirred for 3 h. The solution is evaporated to dryness, the residue is dissolved in DMF, 22.57 g (0.16 mol) of methyl iodide are added dropwise at 20° C. and the mixture is stirred for 24 h. It is worked up and purified analogously to compound 3b. Yield: 21.06 g of 11 (=80% of theory)
Wird geladen…
