Photochemie von 1‐Methoxybicyclo[2.2.2]octenonen; photolytische Cyclopropanspaltung der primär gebildeten Tricyclo[3.3.0.0^2,8]octan‐3‐one

Abstract

[91 Gleichsinnige, wenn auch weniger ausgepragte Anderungen der Bindungslilngen beobachtet man auch beim Ubergang vom mono-zum di- Belichtungen (A =300 nm) von Argon-gesattigten lproz. Losungen von l b und lc in einem Gemisch aus Aceton und Isopropylalkohol (2 : 1) bei Raumtemperatur ergaben 3b bzw

Stereoelectronic control of Cope rearrangement energetics through remote double bonds in novel, rigid polycyclic frames

“…In a recent communication, we reported ' that irradiation (sunlight) of the novel nonacyclic dione 1 gave a photoproduct 2a+, through an uncommon photochemical P-cleavage-cyclobutane fragmentation process. 2 The spectral properties of 2a-c in solution and the X-ray structure in the solid state were compatible with a Cope-equilibrium process.' This interesting finding and the potential synthetic utility of the Cope-isomers, prompted us to amplify this observation to closely related systems 3 and 5 and the corresponding saturated polycyclic derivatives 7, 9 and 11.…”