Rotational Isomerization of (<i>E</i>)-(2-Anthryl)ethenes. A Consideration Why Are the<i>s-cis</i>Rotamers More Stable than the<i>s-trans</i>Rotamers in the Excited State and Less Stable in the Ground State?
作者:Takashi Karatsu、Hajime Itoh、Nobuko Yoshikawa、Akihide Kitamura、Katsumi Tokumaru
DOI:10.1246/bcsj.72.1837
日期:1999.8
absorption, emission and transient absorption spectra with those of the model compounds. The s-trans isomer is more stable than the s-cis rotamer in the ground state; however, the s-cis isomer is more stable than the s-trans rotamer in the excited state (the lowest singlet and triplet excited state). In the triplet excited state, s–trans → s–cis one-way rotational isomerization is observed with activation
(E)-1-(2-蒽基)-2-苯基乙烯 (E-2APE) 和 (E)-1-(2-蒽基)-3,3-二甲基的 s-cis 和 s-trans 旋转异构体之间的旋转异构现象-1-丁烯 (E-2ADB) 通过与模型化合物的吸收、发射和瞬态吸收光谱进行比较来研究。s-反式异构体在基态下比s-顺式旋转异构体更稳定;然而,在激发态(最低的单线态和三线态激发态),s-顺式异构体比s-反式旋转异构体更稳定。在三重激发态下,E-2APE 和 E-2ADB 的活化能分别为 30 和 18 kJ mol-1,观察到 s-trans → s-cis 单向旋转异构化。