Iodoethane → N-Ethylphenothiazine

Participants

Reaction Steps

Into a 1-liter reaction flask were introduced 25 g (0.126 mol) of phenothiazine, 50.0 g (0.757 mol) of 85% KOH, 4.3 g (0.013 mol) of tetra-n-butylammonium hydrogensulfate, 28.0 g (0.203 mol) of potassium carbonate, and 500 ml of toluene. Thereto was gradually added 39.0 g (0.250 mol) of ethyl iodide. The mixture was reacted at 60° to 70° C. for 5 hours and then filtered. The filtrate was washed twice with water, dried with magnesium sulfate, and then concentrated. As a result, 28.7 g of a crude reaction product was obtained. This crude product was recrystallized from 100 ml of isopropanol to obtain 23.99 g of 10-ethylphenothiazine (4a). Yield, 84.1%; m.p., 104°-105° C.

Provenance & Evidence