Generation of Stable Biradical Intermediates in Intramolecular Photo-Cycloaddition of Aromatic Compounds

为了建立芳香光环加成反应的高度立体性和半选择性，并阐明双自由基中间体的参与，研究了n -萘胺和n -氨基胺的光化学反应。(1)光环加成的分子间和分子内选择；在N-cimmanoylnaphthamides的光环加成反应中，根据取代基的不同，在溶液中发生分子内的环加成反应，在固相反应中发生分子间的环加成反应。(2)周边选择性控制；这是在N-1-（1-萘基）乙基胺和N-1-（1-萘基）乙基丙烯酰胺的光环加成反应中实现的。前者实现了分子内[4+2]环加成，后者实现了[2+2]环加成。(3)具有烯酮双键的苯环的新型[2+2]光环加成；这种罕见的[2+2]光环加成反应在n -苯甲酰胺中被观察到。(4)双自由基中间体的生成及其与分子氧的捕获；n -萘酰萘酰胺分子内光环加成反应生成1,8双基中间体。生成的双自由基中间体被分子氧有效捕获。用激光闪光光解法测定中间体的寿命。(5)不对称光[4+4]环加成；在n -蒽基萘胺的固态光化学反应中，首次实现了芳香光环加成的绝对不对称合成。

In order to establish the highly stereo and peri-selective in an aromatic photo-cycloaddition and to elucidate the involvementof biradical intermediates, photochemical reactin of N-naphthamides and N-cimmamides were examined.,(1) Inter- and Intra- molecular selection of photo-cycloaddition ; In the photo-cycloadditin of N-cimmanoylnaphthamides, the intramolecular cycloaddion occurred in solution and the intermolecular cycloadition was achieved in the solid state reaction depending on the substituents.(2) The control of the peri-selectivity ; This was achieved in the photo-cycloaddition of N-1- (1-naphthyl) ethyl-cimmamides and N-1- (1-naphthyl) ethylacryl amides. In the former, the intramoleclar [4+2] cycloaddition was achieved and the [2+2] cycloaddition was achieved in the latter.(3) Novel [2+2] photo-cycloaddition of a benzene ring with an enone double bond ; This rare example of the [2+2] photo-cycloaddition was observed in N-benzoylcimmamides.(4) Generation of a biradical intermediate and its trapping with molecular oxygen ; The 1,8 biradical intermediate was generated in the intramolecular photo-cycloaddition of N-naphthoylnaphtamides. The generated biradical intermediate was efficiently trapped with molecular oxygen. The life time of the intermedaite was determined by laser flash photolysis.(5) Asymmetric photo [4+4] cycloaddition ; The first example of an absolute asymmetric synthesis in aromatic photo-cycloaddion was achieved in the solid-state photochemistry of N-anthronylnaphthamieds.