Photosensitized Oxidations of Substituted Pyrroles: Unanticipated Radical-Derived Oxygenated Products
作者:Mariza N. Alberti、Georgios C. Vougioukalakis、Michael Orfanopoulos
DOI:10.1021/jo9012942
日期:2009.10.2
22) were isolated and characterized. Photooxidation of 2,5-dimethyl-substituted pyrrole 10 in aprotic solvents unexpectedly afforded aldehyde 23 as the major product. Moreover, photooxidation of pyrrole adduct 10 in protic solvents exclusively gave the unprecedented solvent-trapped products 24−27. The formation of products 11−22 was rationalized by the intermediacy of a common endoperoxide intermediate
吡咯加成物的光氧化7 - 10已经以建立对所得氧化产物的形成一般的反应模式和机制进行了研究。反应使用I型和II型敏化剂在几种溶剂中进行。在大多数情况下,光氧化会产生复杂的产物混合物。在这些产品中,5,5-或6,5-双环内酰胺(11,15,和19),马来酰亚胺12种不饱和γ β-内酰胺类(16和20),5- hydroxylactams(13,17,和21)和5 -甲氧基内酰胺(14,18和22)进行了分离和表征。在非质子溶剂中2,5-二甲基取代的吡咯10的光氧化意外地得到醛23作为主要产物。此外,吡咯加成物的光氧化10在质子溶剂只得到前所未有的溶剂捕集产品24 - 27。的产物的形成11 - 22通过一个共同的内过氧化物中间体,其可通过I型来形成和II型机制的中间性合理化。化合物23 - 27分别经由电子转移机理最可能形成。