反应详情

Into the cathode chamber of an electrolytic cell divided with an ion-exchange resin diaphragm was placed a solution of 10 mmols of methyl phenylacetate, 12 mmols of ethyl methanesulfonate and 1.0 g of tetraethylammonium tosylate in 30 ml of anhydrous dimethylformamide. And the anode chamber was provided with a solution of 1.0 g of tetraethylammonium tosylate in 10 ml of anhydrous dimethylformamide. Constant current electrolysis was performed at 0.2 A/cm2 with use of platinum for the cathode and carbon for the anode. After passing 1.5 F of electricity per mol of the methyl phenylacetate through the solution at 5 to 10 C, the cathode solution was added to a saturated aqueous solution of ammonium chloride and the mixture was extracted twice with ether. The ether was distilled off and the residue was purified by silica gel column chromatography using hexane-ethyl acetate (10:1), giving methyl α-ethylphenylacetate in a yield of 77% and α-ethylphenylacetic acid in a yield of 13%. The spectral data of the ester were as follows.

1. extractionthe mixture was extracted twice with ether
2. distillationThe ether was distilled off
3. customthe residue was purified by silica gel column chromatography