Monodisperse Giant Porphyrin Arrays

Our synthetic attempts for the preparation oligo‐ and polyporphyrin arrays were reviewed in comparison with recent accomplishment in the related field. Especially, the synthesis and structural characteristics of huge monodisperse meso‐meso linked porphyrin arrays with multidimensional architectures were focused. The Ag^I‐promoted meso‐meso coupling reaction of 5,15‐diaryl and 5,10,15‐triaryl Zn^II‐porphyrins is advantageous in light of its high regioselectivity, as well as its easy extension to large porphyrin arrays. When applied to 1,4‐phenylene‐bridged linear porphyrin substrates, the coupling reaction gave three‐dimensionally arranged windmill‐shaped and grid‐shaped porphyrin arrays. The meso‐meso coupling doubling reaction was repeated up to the synthesis of a discrete 128‐mer. During these attempts, many porphyrin arrays were isolated in a discrete form by repetitive gel‐permeation chromatography and, interestingly, all the arrays exhibited high solubility in common organic solvents in spite of their giant molecular size. Furthermore, the Ag^I‐promoted coupling reaction was extended to the preparation of long polyporphyrinylenes under slightly modified conditions by either adding N,N‐dimethylacetamide (DMA) or heating slightly.