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Updated: Jun 17, 2026

Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Interfacial molecular assemblies of metalloporphyrins with two trans or one axial ligands
Pingping Yao1, Yunfeng Qiu, Penglei Chen
1Beijing National Laboratory for Molecular Science, CAS Key Laboratory of Colloid, Interface and Chemical Thermodynamics, Institute of Chemistry, Chinese Academy of Sciences, P. R. China.
Abstract:
Molecular assemblies of metalloporphyrins trans-dichloro(5,10,15,20-tetra-p-tolylporphyrinato)tin(IV) (SnCl2TPPMe) and trans-dihydroxo(5,10,15,20-tetra-p-tolylporphyrinato)tin(IV) (Sn(OH)2TPPMe), which have two trans axial ligands, as well 5,10,15,20-tetrakis(4-methoxyphenyl)-21H,23H-porphine iron(III) chloride (FeClTPPOMe) and 5,10,15,20-tetraphenyl-21H,23H-porphine manganese(III) chloride (MnClTPP), which have one axial ligand, are interfacially organized by Langmuir and Langmuir-Blodgett (LB) techniques. SnCl2TPPMe and Sn(OH)2TPPMe form nanofibrous structures which can display distinct supramolecular chirality, although the molecular units themselves are achiral, while FeClTPPOMe and MnClTPP form irregular nanoparticles that display negligible supramolecular chirality. An interpretation in terms of the effects of the axial ligands is proposed for this interesting phenomenon. Moreover, compared with assemblies of the diprotonated free-base porphyrins, which are fabricated by interfacial (air/2.4 M HCl) organization of free-base porphyrin, those of SnCl2TPPMe and Sn(OH)2TPPMe display higher stability in terms of supramolecular chirality. These results indicate that the assembly properties of metalloporphyrins can essentially be affected by the axial ligands that are attached to their chromophores, and that stable chiral porphyrin supramolecular associations can be easily produced by using achiral metalloporphyrins bearing two trans axial ligands.
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