Strained Porphyrin Tape-Cycloparaphenylene Hybrid Nanorings

Org Lett. 2023 Jan 20;25(2):378-383. doi: 10.1021/acs.orglett.2c04089. Epub 2023 Jan 10.

Abstract

V-Shaped porphyrin dimers, with masked p-phenylene bridges, undergo efficient oxidative coupling to form meso-meso linked cyclic porphyrin oligomers. Reductive aromatization unmasks the p-phenylenes, increasing the strain. Oxidation then fuses the porphyrin dimers, providing a nanoring with curved walls. The strain in this macrocycle bends the p-phenylene and fused porphyrin dimer units (radii of curvature of 11.4 and 19.0 Å, respectively), but it does not significantly alter the electronic structure of the fused porphyrins.