Photochemical rearrangements of 2-carboxy-3-keto-9-methyl-Δ1,4-hexahydronapthalene

✍ Scribed by Drury Caine; John F. DeBardeleben Jr; J. Byron Dawson

• Book ID: 104235170
• Publisher: Elsevier Science
• Year: 1966
• Tongue: French
• Weight: 291 KB
• Volume: 7
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(01)82840-9

✦ Synopsis

Recently, we reported the conversion of 2-fonqyl-3-keto-9-methyl-Al,4 -hexahydronaphthalene into a perhydroazulene derivative by irradiation in aqueous acetic acid followed by base treatment of the photo-product (1).

We now have found that L4 2-carboxy-3-keto-g-methyl-A -hexahydronaphthalene (I) is converted in high yield into 5/V-fused products on irradiation in aqueous and non-aqueous media. The dienone acid I was prepared either by the procedure of Dreiding and Tomasewski (2) or by oxidation of the corresponding formyl compound with Jones' reagent (3). Irradiation of I at room temperature using a Hanovia 450 watt immersion light source and a Pyrex filter in aqueous acetic acid, aqueous dioxane, anhydrous dioxane, and methanol gave various mixtures of products II-V. The yields of these products and the reaction conditions are shown in Table I. The photo-products were separated by chromatography on alumina or silica gel. The dienones IV and V were difficult to separate using column chromatography and mixtures of these were analyzed by v.p.c.