[Na].C[Si](C)(C)N[Si](C)(C)C.[Cl:11][C:12]1[CH:17]=[CH:16][C:15]([CH2:18][C:19]([OH:21])=O)=[CH:14][CH:13]=1.[Cl:22][C:23]1[CH:32]=[C:31]([Cl:33])[CH:30]=[CH:29][C:24]=1C(OC)=O.Cl>C1COCC1>[Cl:11][C:12]1[CH:13]=[CH:14][C:15]([CH2:18][C:19]([C:30]2[CH:29]=[CH:24][C:23]([Cl:22])=[CH:32][C:31]=2[Cl:33])=[O:21])=[CH:16][CH:17]=1420 ml of a 2M solution of the sodium salt of hexamethyldisilazane in THF are cooled to −60° C. under a nitrogen atmosphere, 350 ml of THF are added, then, dropwise, a solution of 57.6 g of 4-chlorophenylacetic acid in 70 ml of THF is added and the mixture is left stirring at −60° C. for one hour. 66 g of methyl 2,4-dichlorobenzoate are subsequently added dropwise at −60° C., the mixture is left stirring at −60° C. for 40 minutes and then the temperature is allowed to rise to 0° C. The reaction mixture is poured onto an ice/1 liter of 2N HCl mixture and extracted with ether, the organic phase is dried over Na2SO4, the solvent is concentrated under vacuum to a volume of 150 ml, 200 ml of pentane are added and the crystalline product formed is filtered off. 60 g of the expected compound are obtained.
読み込み中…
