A mixture of 4.70 g (0.029 mole) of 1,1'-carbonyldiimidazole- and 3.07 g (0.0265 mole) of N,N-diethylethylenediamine in 400 ml of tetrahydrofuran was stirred at room temperature for 1 hr. A solution of 8.00 g (0.0245 mole) of N-[2-(phenylsulfinyl)ethyl]-2-propanamine in 50 ml of tetrahydrofuran was added, and the mixture was refluxed for 16 hr. The solvent was removed in vacuo, and the residue was dissolved in ether. The ether solution was extracted with several portions of water. The aqueous extract was extracted with ether and then with methylene chloride; these organic extracts were combined with the original ether solution. The organic solution was dried over magnesium sulfate, and the solvent was removed in vacuo to give an oil. Flash chromatography on silica gel (methanol) gave 4.84 g (55.9%) of oil:
