NEW SYNTHESES OF CYCLOPENTA[CD]PYRENE 3,4-OXIDE AND 4-PYRENYLACETIC ACID

New syntheses of cyclopenta[cci]pyrene 3,4-oxide (CPPE) and 4-pyrenylacetic acid, a key intermediate in the synthesis of cyclopenta[cd]pyrene and CPPE, are described starting from 1,2,3,6,7,8-hexahydropyrene. 4-Pyrenylacetic acid is prepared from the corresponding alcohol, 2-(4-pyrenyl)ethanol, by applying two mild oxidation reactions. 4-Pyrenylacetaldehyde was obtained by N-chlorosuccinimide dimethyl sulfide oxidation, and this was converted smoothly to the desired 4-pyrenylacetic acid by silver oxide oxidation, an approach that has potential for a new route to arylacetic acids from arylethanols. The epoxide CPPE is prepared by cyclization of the 3,4-frans-dihydroxycyclopenta[cd]pyrene via its monotosylate, prepared in situ, with powdered sodium hydroxide. © 1990, American Chemical Society. All rights reserved.