Photosantoninic Acidの構造研究 (第5報)

抄録

According to the model experiment reported in the previous paper, photosantoninic acid (I) was reacted with boiling aqueous alkali but only formed an unidentified resinous product. However, when this reaction was carried out in the presence of zinc dust, I afforded two crystalline products, C₃₀H₄₂O₇ and C₃₀H₄₆O₈, depending on reaction conditions. The former, for which the structure (II) was proposed, was formed under mild condition. The latter, to which the structure (VII) was suggested, was obtained by prolonged treatment of I or II with 1.5N sodium hydroxide solution and zinc dust. A probable mechanism of the formation of VII from II is shown in Chart 2. Selenium dehydrogenation of the catalytic hydrogenation product of VII afforded none of binaphthalene derivative but only 2-ethyl-5-methylnaphthalene, resulting from a pyrolytic scission of the carbon-carbon bond linking two decalin skeletons of VII.