Intramolecular Diels–Alder Reaction of a Biphenyl Group in a Strained meta -Quaterphenylene Acetylene
Intramolecular Diels–Alder Reaction of a Biphenyl Group in a Strained meta -Quaterphenylene Acetylene
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应变间位四联苯乙炔中联苯基的分子内狄尔斯·阿尔德反应
DOI：
10.1021/acs.joc.2c02280
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Frantz, Derik K.
中科院分区：
文献类型：
--
作者：
Mittal, Komal;Pham, Ashley V.;Davis, Amanda G.;Richardson, Abigail D.;De Hoe, Clement;Dean, Ryan T.;Baird, Vi;McDonald, Ashley Ringer;Frantz, Derik K.
在高温下，应变的环状间四亚苯基乙炔发生分子内环化反应，形成苯并[e]茚并[1，2，3-hi]乙酰菲。该反应代表了在联苯衍生物的2-、1-、1′-和2′-位上的狄尔斯-阿尔德反应的一个实例，该区域类似于二萘嵌苯和其他过并苯的海湾区域。该反应以高转化率清洁地进行。对甲基化衍生物的动力学研究表明，反应的ΔG ε = 1.40 -41 kcal/mol，计算模型预测[4 + 2]-环加成过渡态的Δ G ε = 1.40 -41 kcal/mol。
At elevated temperatures, a strained, cyclicmeta-quaterphenylene acetylene undergoes an intramolecular cyclization reaction to form benz[e]indeno[1,2,3-hi]acephenanthrylene. This reaction represents an example of a Diels–Alder reaction at the 2-, 1-, 1′-, and 2′-positions of a biphenyl derivative, a region analogous to the bay regions of perylene and other periacenes. The reaction proceeds cleanly with high conversion. Kinetics studies of a methylated derivative reveal that the ΔG‡for the reaction is ∼40–41 kcal/mol, and computational models predict a similar value ofGrelfor the transition state of a concerted [4 + 2]-cycloaddition.