Photophysics and Photochemistry of Cyclic Enones

环烯酮的光物理学和光化学

• 批准号: 8900099
• 负责人: David Schuster
• 金额: $ 22.01万
• 依托单位: New York University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-03-01 至 1993-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8900099&HistoricalAwards=false
• 关键词: Photophysics; Photochemistry; Cyclic; Enones

This award is made in the Organic Dynamics Program to support the research of Dr. David Schuster of New York University on the photochemistry and photophysics of cyclic unsaturated ketones. Properties of triplet excited states and reaction intermediates formed in the photoexcitation of cyclic enones in the presence and absence of alkenes will be studied by nanosecond flash photolysis, photoacoustic calorimetry and time-resolved resonance Raman spectroscopy. The goal is to obtain data which will allow specification of the molecular structures and energies of singlet and triplet states, strained trans isomers of cyclic enones and of triplet 1,4-biradical intermediates. These studies will establish how energetic relaxation in cyclic enone triplets is affected by ring size and substitution and how molecular structure affects rates of spin inversions to ground states from triplet excited states, a matter of fundamental significance in organic photochemistry. Mechanistic studies of the synthetically important photocycloaddition of cyclic enones to olefins will be carried out. In particular, secondary deuterium isotope effects will be determined for quenching of enone triplets by alkenes and for formation of cycloadducts in order to determine if enone-alkene exciplexes of any kind are on the reaction pathway to triplet 1,4-biradicals.

该奖项是在有机动力学计划，以支持 纽约大学的大卫舒斯特博士关于 环状不饱和烃光化学和光物理 酮。 三重激发态和反应中间体的性质 在环烯酮存在下的光激发中形成 和不存在烯烃将通过纳秒闪光进行研究 光解、光声量热和时间分辨 共振拉曼光谱。 目标是获得数据， 将允许分子结构的规格， 单重态和三重态的能量，应变反式异构体 环状烯酮和三重态1，4-双自由基中间体。 这些研究将确定如何在循环的能量放松 烯酮三联体受环大小和取代的影响， 分子结构如何影响自旋反转速率， 基态从三重激发态， 在有机光化学中具有重要意义。 综合重要性的机制研究 将进行环烯酮与烯烃的光环化加成 出去 特别是，次级氘同位素效应将 被确定为通过烯烃猝灭烯酮三重态， 用于形成环加合物，以确定 任何种类的烯酮-烯烃激基复合物都在反应途径上 三重1，4-双自由基