Proof for the Concerted Inversion Mechanism in the trans→cis Isomerization of Azobenzene Using Hydrogen Bonding To Induce Isomer Locking
Proof for the Concerted Inversion Mechanism in the trans→cis Isomerization of Azobenzene Using Hydrogen Bonding To Induce Isomer Locking
复制标题
DOI：
10.1021/jo100866m
复制
发表时间：
2010-07-16
影响因子：
3.6
通讯作者：
Burdette, Shawn C.
中科院分区：
文献类型：
--
作者：
Bandara, H. M. Dhammika;Friss, Tracey R.;Burdette, Shawn C.
偶氮苯在辐照下发生可逆的顺反光异构化。取代基经常改变偶氮苯的异构化行为，但并不总是以预测的方式。报道了三种偶氮苯衍生物AzoAMP-1、-2和-3的合成和性质。AzoAMP-1（2，2 '-双[N-（2-吡啶基）甲基]二氨基偶氮苯）在偶氮基团邻位具有两个氨甲基吡啶基团，表现出最小的反-顺光异构化和极其快速的顺-反热恢复。AzoAMP-1在固态下采用平面构象，并且当在77 K下冷冻在1：1的二乙醚/乙醇基质中时比偶氮苯更具有发射性（Phi（fl）= 0.003）。苯胺基质子与吡啶基和偶氮基氮原子之间的两个强分子内氢键是这些不寻常性质的原因。计算数据预测AzoAMP-1在S-2之后不应异构化
Azobenzene undergoes reversible cis()trans photoisomerization upon irradiation. Substituents often change the isomerization behavior of azobenzene, but not always in a predictive manner. The synthesis and properties of three azobenzene derivatives, AzoAMP-1, -2, and -3, are reported. AzoAMP-1 (2,2'-bis[N-(2-pyridyl)methyl]diaminoazobenzene), which possesses two aminomethylpyridine groups ortho to the azo group, exhibits minimal trans cis photoisomerization and extremely rapid cis trans thermal recovery. AzoAMP-1 adopts a planar conformation in the solid state and is much more emissive (Phi(fl) = 0.003) than azobenzene when frozen in a matrix of 1:1 diethylether/ethanol at 77 K. Two strong intramolecular hydrogen bonds between anilino protons and pyridyl and azo nitrogen atoms are responsible for these unusual properties. Computational data predict AzoAMP-1 should not isomerize following S-2