DIENONES DERIVED FROM 5-METHOXY[2.2]METACYCLOPHANES

Treatment of 5,13-dimethoxy[2.2]metacyclophane (4) under the conditions of the Rieche reaction gives predominantly the corresponding 8-formyl derivative (5). Attempts to convert 5 into a methylene-bridged cis-[2.2]metacyclophane were unsuccessful. However, 5 could be converted into the corresponding 8-methyl derivative (7) and this in turn was oxidized to the corresponding dienone (8). Also, it has been shown through the preparation of 5-methoxy-8-methyl[2.2]metacyclophane (11) that the Wurtz reaction can be used effectively to prepare “mixed dimeric” products. Oxidation of 11 gave the corresponding dienone 12 and treatment of 12 with acetic anhydride and perchloric acid readily effected a dienone-phenol type of rearrangement to give 2-acetoxy-3-methyl-4,5,9,10-tetrahy dropyrene (13). © 1969, American Chemical Society. All rights reserved.