Photochemical reactions with non-conjugated dienes

摘要: INTRODUCTION Electronic interactions between classically non-conjugated, by one or several sp3-hybridized carbon-atoms insulated centres, have been studied intensively. Today, homoallylic ions and homoaromatic compounds, to mention a few, are experimentally well documented theoretically understood'. Far less settled is the state of affairs when we talk about in excited states. Such nominally unconjugated, supposedly simple chromophores observed number chemically distinct systems, but physical interpretation these observations turned out be rather difficult, even for case two C=C double bonds2. In this I would like present some further examples where light-induced within homodieneand homovinyl-cyclopropane systems used synthesis valuable, other means hardly accessible, products. first part will start from known photoisomerization reaction. Following original report Cristol Snell3 intramolecular cycloaddition reaction norbornadiene—quadricyclane (I) — (II)