反应详情

12.5 g (0.034 mol) of 2-(4-(2-parachlorobenzamidoethyl)phenoxy)-2-methylpropionic acid are dissolved in 100 ml of anhydrous dimethylformamide, and 4.8 g of 3,3,5-trimethylcyclohexanol (transform) (0.034 mol) and 0.5 g of dimethylaminopyridine are added. After solubilization, a solution of 7 g of dicyclohexylcarbodiimide (0.034 mol) in 20 ml of dimethylformamide is added slowly at a temperature of around 0° C. The reaction is allowed to continue for 24 hours at ordinary temperature and the precipitate of dicyclohexylurea is filtered off; after evaporation of the filtrate under reduced pressure, the residue is chromatographed on a silica column in a mixture of petroleum ether and ethyl acetate. After evaporation of the solvent, the title derivative is obtained in the form of white crystals melting at 100° C.; the yield is 45%. This product, chromatographed under the conditions of Example 1, shows a single spot of Rf 0.2. The IR spectrum run in KBr has the following characteristic bands: one broad band at 3250 cm-1, a group of fine bands at 3000-2840 cm-1 an strong bands at 1750 cm-1 and 1640 cm-1.

1. filtrationthe precipitate of dicyclohexylurea is filtered off
2. customafter evaporation of the filtrate under reduced pressure
3. customthe residue is chromatographed on a silica column in a mixture of petroleum ether and ethyl acetate
4. customAfter evaporation of the solvent