Department of Chemistry, University of Sussex, Brighton, BN1 9QJ, UK.
J Org Chem. 2011 Mar 4;76(5):1295-304. doi: 10.1021/jo101927a. Epub 2011 Feb 4.
The double [3 + 2] photocycloaddition reaction involving arenyl-dienes has been used to assemble seven separate [5.5.5.5] fenestrane structures that include ether and aza variants. The primary photolysis step was a meta photocycloaddition reaction, while a secondary photocycloaddition step formed the fenestrane structure. Investigations involving the insertion of an additional methylene group into the basic arenyl-diene skeleton failed to afford the desired [5.5.5.6] fenestrane structure. The presence of an oxime moiety in the aromatic photosubstrate allowed the primary photolysis step to take place; however, an attempted secondary photocycloaddition reaction involving the oxime did not provide the intended polyheterocyclic fenestrane. An alternative strategy to form various "criss-cross" double meta photocycloadducts was investigated and led to the discovery of a Paterno-Büchi cycloaddition reaction between acetone and an angular meta photocycloadduct. Other novel thermally and photochemically mediated skeletal rearrangement reactions were also recorded.
双[3+2]光环加成反应涉及芳基-二烯，已被用于组装七个独立的[5.5.5.5] fenestrane 结构，包括醚和氮杂变体。主要的光解步骤是间位光环加成反应，而次级光环加成步骤形成 fenestrane 结构。涉及在基本芳基-二烯骨架中插入额外的亚甲基的研究未能获得所需的[5.5.5.6] fenestrane 结构。芳香族光底物中肟部分的存在允许主要光解步骤发生；然而，肟的次级光环加成反应并没有提供预期的多杂环 fenestrane。形成各种“交叉”双间位光加合物的替代策略也进行了研究，并发现了丙酮与角间位光加合物之间的 Paterno-Büchi 环加成反应。还记录了其他新的热和光化学介导的骨架重排反应。
