Singlet oxygen mediated photofragmentation reactions of amino alcohols: a novel oxidative fragmentation involving both superoxide and excited oxygen intermediates
作者:Christian M. Haugen、David G. Whitten
DOI:10.1021/ja00200a069
日期:1989.8
Etude de la fragmentation sous rayonnement visible de β-dialkylamino α-phenyle benzeneethanols. Obtention d'amines secondaires et d'aldehydes
Etude de la 碎裂sous rayonnement 可见de β-二烷基氨基α-苯基苯乙醇。获得二胺和二醛
Singlet oxygen mediated fragmentation of amino alcohols, 1,2-diamines, and amino ketones
作者:Christian M. Haugen、William R. Bergmark、David G. Whitten
DOI:10.1021/ja00052a027
日期:1992.12
proposed for the reaction with singlet oxygen sensitizers in which singlet oxygen initiates reaction by SET oxidation of the amine donors and subsequent reaction from the resulting superoxide-amine cation ion radical pair. For reaction with amino ketones under the same conditions, irradiation results in formation of novel fragmentation products incorporating oxygen. Labeling studies with O-18 enriched
在有取代胺(氨基醇、1,2-二胺和氨基酮)存在的情况下,辐照单线态氧敏化剂(如玫瑰红、玫瑰红衍生物或四苯基卟啉钯)的充气溶液会导致良好化学物质中胺的氧化碎裂产量和低到中等的量子效率。对于氨基醇和 1,2-二胺,反应过程类似于由电子转移敏化剂(如硫靛或氰基芳烃)照射引发的反应过程。在这些情况下,已显示反应通过胺的单电子转移氧化和随后胺阳离子自由基的裂解进行。对于与单线态氧敏化剂的反应提出了类似的机制,其中单线态氧通过胺供体的 SET 氧化引发反应,随后产生的超氧化物-胺阳离子自由基对反应。对于在相同条件下与氨基酮反应,辐照导致形成新的掺入氧的碎裂产物。使用富含 O-18 的氧气进行的标记研究表明,空气是产品中某些掺入氧气的来源,并提出了与其他碎裂过程密切相关的机制。42 个参考文献,1 个标签。使用富含 O-18 的氧气进行的标记研究表明,空气是产品中某些掺入氧气的来源,并提出了与其他碎裂过程密切相关的机制。42
Photoinduced electron-transfer fragmentation of amino alcohols: stereochemical effects and connectivity between one- and two-electron events
作者:Xiaohong Ci、Lester Y. C. Lee、David G. Whitten
DOI:10.1021/ja00242a061
日期:1987.4
formed by photoinducedelectrontransfer are of considerable current interest. Among the possible fates of ions formed by heteroatom oxidations is C-C bondfragmentation. Recently they reported that certain tertiary amines suffer C-C bond cleavage when oxidized by acceptors excited by visible light. For amino ketones this reaction was indicated to proceed via homolytic cleavage of the bond between the
通过光致电子转移形成的自由基离子或自由基离子对的反应是当前相当受关注的。由杂原子氧化形成的离子的可能命运之一是 CC 键断裂。最近他们报告说,某些叔胺在被可见光激发的受体氧化时会发生 CC 键断裂。对于氨基酮,表明该反应通过羰基和胺的 C/sub..cap alpha../ 之间的键的均裂进行,以有效地产生自由基。在此,他们报告了对几种 ..beta..-氨基醇的研究,这些研究证明光氧化还原诱导的 C/sub ..cap alpha../-C/sub ..beta../ 键的裂解可以是一种干净有效的反应与两电子溶剂分解碎裂非常相似。
Photochemical dehydrofragmentation reactions: importance of donor and acceptor structure in determination of reactivity in radical ion pairs formed in electron transfer photoreactions
作者:Xiaohong Ci、David G. Whitten
DOI:10.1021/ja00257a066
日期:1987.11
efficient C-C bond photofragmentation reactions of ..beta..-amino-alcohols initiated by electron transfer to excited acceptors. They report here a mechanistic study where this reaction is restricted to the geminate pair and which emphasizes the complimentary roles of reduced acceptor and oxidized donor in facilitating chemical reaction in competition with fast back electron transfer. Amore » key result is
Rose bengal-induced photofragmentation: Singlet oxygen revisited
作者:Gary A. Epling、Martha L. Jackson
DOI:10.1016/0040-4039(91)80519-c
日期:1991.12
The Rose Bengal-induced photofragmentation of β-amino alcohols has been previously reported to proceed through a mechanism involving singletoxygensensitization, followed by attack of singletoxygen and superoxide on the β-amino alcohol. An alternative mechanism involving electron transfer from the amine to the excited state RoseBengal is supported by new evidence.