The first synthesis to construct coumarin-fused pyrido[2,3-b]porphyrins has been accomplished via a cascade reaction of 2-amino-meso-tetraphenylporphyrins, aromatic aldehydes and 4-hydroxycoumarin in o-dichlorobenzene containing a stoichiometric amount of trichloroacetic acid under reflux conditions. The methodology presented herein provides a direct access to a new series of π-extended nickel(II) and copper(II) porphyrin analogues in 58–69% isolated yields under one-pot operation. Furthermore, coumarin-fused copper(II) pyrido[2,3-b]porphyrin underwent demetalation under the influence of concentrated sulfuric acid to produce free-base porphyrin which on zinc metal insertion using zinc acetate in a chloroform–methanol mixture afforded coumarin-fused zinc(II) pyrido[2,3-b]porphyrin in good yield. The structures of the newly prepared coumarin-fused pyrido[2,3-b]porphyrins were established on the basis of spectral data analysis. In comparison with meso-tetraphenylporphyrin precursors, these porphyrinoids demonstrated a significant red-shift in their electronic absorption and emission spectra.

中文翻译：

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三氯乙酸促进多米诺骨牌方法构建香豆素融合的吡啶并[2,3-b]卟啉

通过2-氨基-内消旋-四苯基卟啉，芳族醛和4-羟基香豆素在含有化学计量的三氯乙酸的邻二氯苯中的级联反应，已经完成了构建香豆素稠合的吡啶并[2,3- b ]卟啉的第一个合成反应。在回流条件下。本文介绍的方法可在一锅操作下以58-69％的分离产率直接获得一系列新的π扩展镍（II）和铜（II）铜卟啉类似物系列。此外，香豆素熔合的铜（II）吡啶基[2,3- b]卟啉在浓硫酸的作用下进行脱金属，生成游离碱卟啉，该游离碱卟啉通过在氯仿-甲醇混合物中使用乙酸锌对锌金属的插入作用，提供了香豆素熔合的吡啶并锌[ II，3 - b ]卟啉。让。在光谱数据分析的基础上，建立了新制备的香豆素融合吡啶并[2,3- b ]卟啉的结构。与内消旋四苯基卟啉前体相比，这些卟啉类化合物在电子吸收光谱和发射光谱中显示出明显的红移。