Hydrochloric Acid → 2-(4-Hydroxyphenyl)indole

Participants

Reaction Steps

4-Hydroxyacetophenone phenylhydrazine (47 g.) was fused with 250 g. zinc chloride (10 min. at 180° C.), poured into 3 l. 0.3 HCl, heated and stirred for 1 hour on the steam bath, cooled to 0° and filtered. The precipitate was extracted with pet. ether and allowed to stand. 2-(p-hydroxyphenyl)indole (17 g., m. 224°-229°) was isolated. A well stirred mixture of 2-(p-hydroxyphenyl)indole (0.1 mole), iodoethane (0.1 mole) and sodium bicarbonate (0.12 mole) in 200 ml. of acetone was refluxed overnight, filtered and the acetone removed on the steambath. The isolated 2-(p-hydroxyphenyl)-1-ethylindole was reacted with 4-(2-bromoethoxy)-2,2,6,6-tetramethylpiperidine as in Example 1 to produce 4-{2-[4-(1-ethyl-2-indolyl)phenoxy]ethoxy}-2,2,6,6-tetramethylpiperidine.

Provenance & Evidence