**1. Introduction**

Metal-coordination polymers are hybrid materials consisting of metal ions or clusters interconnected by rigid organic molecules (tectons) [1,2]. The ordering of the components in three dimensions, the possibility to use tectons of different natures and sizes, and the dynamic properties of the frameworks provide coordination polymers with unique luminescent, nonlinear optical, redox, magnetic, sorption, catalytic, ion exchange, sensory, and other properties [3–10] Due to their structure and unique physicochemical and photophysical characteristics, particularlytheir photoactivity, optoelectronic, and electrochemical properties, tetrapyrrole molecules are extremely promising objects for the construction of metal-coordination polymers for various purposes [11–19]. It is known that metal complexes of porphyrins and porphyrinoids are capable of selective reversible binding of substrate molecules and, thus, can be used to construct simple and complex supramolecular systems of various dimensions and architecture [20–27].

The aim of this work was to obtain new hybrid coordination oligomers and 1Dpolymers with chelating binding of Sn(IV)-porphyrindiaxial complexes (*bis*-thyrazine-Sn(IV)-5,10,15,20-(4-sulfonatophenyl)porphyrin (I) and *bis*-diaminohydroquinone-Sn(IV)- 5,10,15,20-(4-sulfonatophenyl)porphyrin (II)) with Cu2+ cations. Structures of the complexes I and II are depicted in Figure 1.

**Citation:** Mamardashvili, G.M.; Lazovskiy, D.A.; Khodov, I.A.; Efimov, A.E.; Mamardashvili, N.Z. New Polyporphyrin Arrays with Controlled Fluorescence Obtained by Diaxial Sn(IV)-Porphyrin Phenolates Chelation with Cu2+ Cation. *Polymers* **2021**, *13*, 829. https://doi.org/ 10.3390/polym13050829

Academic Editor: Jung-Chang Wang

Received: 19 February 2021 Accepted: 5 March 2021 Published: 8 March 2021

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**Figure 1.** Structures of the complexes I and II.

Complexes I and II were used as tectons coordinating through Cu2+ cations. Such ligands have the ability to form stable chelate cycles with *d*-metal cations due to the simultaneous interaction of the metal cation with the ligand reaction centers of different natures(the hydroxyl group oxygen and amino group nitrogen) [28]. Chain oligomerization of the Sn(IV)-porphyrindiaxial complexes (SnP(L)2) via Cu2+ cations is ensured by one copper cation forming two stable five-membered chelate rings, with the axial ligands belonging to the neighboring porphyrinates. The result of this oligomerization is the formation of stable nanoparticles (in comparison with less stable oligomers, which can be formed by four- or six-membered chelate rings based on copper cations), the sizes and properties of which depend on the nature of the axial ligands and the concentration ratio of the Sn(IV) porphyrin axial complexes and *d*-metal cations. Coordination oligomers or polymers of this type are of particular interest to those involved in creating new 'chemo-responsive' (i.e., selectively interacting with other chemical species as receptors, sensors, or photocatalysts) or 'size-responsive' (i.e., capable of separating, storing, and transporting aggressive, toxic or explosive chemical species of different nature) materials, with their functional properties controlled by the number of monomeric fragments in the polyporphyrin arrays.
