Crystal engineering of porphyrin framework solids

Abstract

This article describes recent achievements made by us and other groups in targeted synthesis of porphyrin-based framework solids by various non-covalent mechanisms of molecular recognition. The self-assembly processes are effected in a tunable manner either by direct association of suitably designed porphyrin building blocks, or by their supramolecular aggregation through external linkers as metal ions and organic bi-dentate ligands. Many of these crystalline porphyrin materials exhibit open architectures and remarkable structural integrity, and their potential application for selective guest storage and molecular sieving is highlighted.

Porphyrin substituent regiochemistry, conformation and packing – the case of 5,10-diphenylporphyrin

“…This provides further information on the structural variability of the various members of the A x -and ABCD-porphyrin family [17]. It also indicates the possibility that the 5,10-disubstituted porphyrins, with appropriate functional groups, might give rise to unique packing arrangements in the context of crystal engineering [18].…”

Crystal structure of catena-(5-(4-carboxyphenyl)-10,15,20-tris(4- carboxylatophenyl)porphyrin-aqua-dimethylformamidedysprosium( III)-nickel(II)– dimethylformamide – water (1:1:1), [(C48H25N4O8Ni)Dy(H2O)(C3H7NO)] · C3H7NO · H2O

“…In this context, the H 4TCPP ligand bears multiple diverging molecular recognition sites for metal coordination in different directions, and is perfectly suitable when reacted with complimentary metal ion connectors for the formulation of singleframework architectures [2][3][4]. We found recently that lanthanoid ions provide avery attractive interface for coordination polymerization with the H 4TCPP building blocks (whether in afree-base or core-metalated form) in three dimensions [5,6].…”

“…This study is part of an extended research project directed at the design and evaluation of porphyrin-based framework solids [2,3]. In this context, the H 4TCPP ligand bears multiple diverging molecular recognition sites for metal coordination in different directions, and is perfectly suitable when reacted with complimentary metal ion connectors for the formulation of singleframework architectures [2-4].…”

Crystal structure of catena-tris(5,10,15,20-(4-carboxylatophenyl)- porphyrin)-aqua-tetradysprosium-trizinc solvate, (C48H24N4O8Zn)3Dy4(H2O) · (solvent)x

“…In this context, the H 4 TCPP ligand bears multiple diverging molecular recognition sites for metal coordination in different directions,a nd is perfectly suitable when reacted with complimentary metal ion connectors for the formulation of singleframework architectures [2][3][4].Wefound recently that lanthanoid ions provide av ery attractive interface for coordination polymerization with the H 4 TCPP building blocks (whether in afreebase or core-metalated form) in three dimensions [5,6]. This is due to their large size, spatial divergence of the valent orbitals, high coordination numbers, and oxophilic nature.…”

“…This study is part of an extended research project directed at the design and evaluation of porphyrin-based framework solids [2,3]. In this context, the H 4 TCPP ligand bears multiple diverging molecular recognition sites for metal coordination in different directions,a nd is perfectly suitable when reacted with complimentary metal ion connectors for the formulation of singleframework architectures [2][3][4].Wefound recently that lanthanoid ions provide av ery attractive interface for coordination polymerization with the H 4 TCPP building blocks (whether in afreebase or core-metalated form) in three dimensions [5,6].…”