Exploring Supramolecular Self-Assembly of Tetraarylporphyrins by Halogen Interactions. 3. Tin(L)2(A2B2-Porphyrin) Arrays Supported by Concerted Halogen and Hydrogen Bonding

This work reports on a designed construction of new porphyrin-based supramolecular architectures assembled with the aid of halogen bonds and a combination of halogen and hydrogen bonding interactions. The tinIV(L)2-tetraarylporphyrin building unit (L = axial ligand) was used to this end, wherein suitable donor and acceptor functions for such bonds have been introduced in a complementary manner on the axial ligands and the porphyrin periphery. We reveal in this context eight structures involving differently substituted metalloporphyrin entities: 5,10,15,20-tetra(4′-iodophenyl)porphyrin (A4-P), 5,10,15,20-tetra(4′-pyridyl)porphyrin (B4-P), 5-(4′-pyridyl)-10,15,20-tris(4′-iodophenyl)porphyrin (A3B-P), and 5,15-bis(4′-pyridyl)-10,20-bis(4′-iodophenyl)porphyrin (A2B2-P), and various axial ligands attached to the tin center and bearing molecular recognition capacity. The latter include 3-hydroxypyridine (L1), hydroxyl (L2), 1-hydroxybenzotriazole (L3), 5-bromopyridine-3-carboxylic acid (L4), 5-bromoisophthalic ...