The electrochemical reduction of two chloro‐substituted 4‐(thiazol‐2‐ylazo)naphthalenes has been studied by means of spectroelectrochemistry and simulated with the DFT method. Whereas the 1‐chloro‐4‐(4‐chlorothiazol‐2‐ylazo)naphthalene forms both a stable radical anion and a dianion, the dianion of 1‐chloro‐4‐(thiazol‐2‐ylazo)naphthalene is instable. In the radical anion of both compounds, the spin densities are high not only at the azo moiety but also at C 3 in the naphthalene and at C 5 in the thiazole moiety. This is in agreement with former experimental results demonstrating the remarkable reactivity of these positions towards thiols which can act as nucleophiles as well as electron donors.

中文翻译：

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关于4-（噻唑-2-基偶氮唑基）取代的1-氯萘的电化学还原：稳定自由基阴离子的形成和表征

通过光谱电化学研究了两种氯取代的4-（噻唑-2-基偶氮）萘的电化学还原，并用DFT方法进行了模拟。1-氯-4-（4-氯噻唑-2-基偶氮）萘同时形成稳定的自由基阴离子和二价阴离子，而1-氯-4-（噻唑-2-基偶氮基）萘的二价阴离子不稳定。在两种化合物的自由基阴离子中，不仅在偶氮部分处而且在萘的C 3处和噻唑部分的C 5处的自旋密度都高。这与以前的实验结果一致，表明这些位置对可以充当亲核试剂和电子供体的硫醇具有显着的反应性。