Comparison of the singlet oxygen ene reactions of cyclic versus acyclic β,γ-unsaturated ketones: an experimental and computational study
Comparison of the singlet oxygen ene reactions of cyclic versus acyclic β,γ-unsaturated ketones: an experimental and computational study
复制标题
DOI：
10.1016/j.tetlet.2013.03.099
复制
发表时间：
2013-06-05
影响因子：
1.8
通讯作者：
de Kiff, Alan
中科院分区：
文献类型：
--
作者：
Griesbeck, Axel G.;Goldfuss, Bernd;de Kiff, Alan
以5-甲基己烯-4-烯-2-酮(1)和环己烯-3-烯-1-酮(6)为模型化合物，通过实验和计算方法研究了两种β， γ -不饱和酮的光氧化作用。开链底物根据建立的顺式选择性模型产生1:1的区域异构体2a，b的混合物，而环状底物与O-1(2)反应优先产生共轭产物7。这种效应与机械的两阶段无中间模型一致，在计算水平上对应于一个区域选择性控制，从谷脊势能表面区域的相应过渡阶段开始，沿着最陡的路径。(C) 2013 Elsevier Ltd.版权所有。
The photooxygenation of two beta,gamma-unsaturated ketones was studied by experimental and computational methods: 5-methyl-hex-4-en-2-one (1) and cyclohex-3-en-1-one (6) as model compounds for acyclic versus cyclic deconjugated enones. The open-chain substrate delivered a 1:1 mixture of regioisomers 2a,b following the established cis-selectivity model whereas the cyclic substrate reacts with O-1(2) to give preferentially the conjugated product 7. This effect is in agreement with the mechanistic two-stage no-intermediate model and on a computational level corresponds to a regioselectivity control following the steepest decent pathway from the corresponding transition stages in a valley ridge potential energy surface region. (C) 2013 Elsevier Ltd. All rights reserved.