A solution of 4.54 g (0.28 mole) of 1,1'-carbonyldiimidazole and 2.90 g (0.025 mole) of N,N-diethylethylenediamine in 400 ml of tetrahydrofuran was stirred at room temperature for 1 hr. A solution of 5.89 g (0.0229 mole) of N-[2-[(4-methoxyphenyl)sulfonyl]ethyl]-2-propanamine in 50 ml of tetrahydrofuran was added, and the mixture was refluxed overnight. The solvent was removed in vacuo, and the residue was dissolved in 800 ml of a 50/50 mixture of methylene chloride-ether. The organic solution was extracted with water and was dried over magnesium sulfate. The solvent was removed in vacuo to give an oil. This was crystallized from ether-hexane to give 6.16 g (67.3%) of white crystalline solid; m.p. 39.5°-42° C.
