Synthesis of dipyrrin-containing architectures

Abstract

Dipyrrins are valuable precursors to dyes [dipyrrinatoboron difluoride, bis(dipyrrinato)-zinc(II) complexes] and serve as ligands in a variety of self-assembled materials. Six new dipyrrin-containing architectures have been synthesized. The architectures include bis(dipyrrinato) complexes containing copper(II) or palladium(II), a dipyrrin bearing a protected phosphonic acid unit, a porphyrin bearing two dipyrrins in a trans configuration, a linear diphenylethyne-linked dipyrromethane-dipyrrin building block, and a triad composed of two zinc porphyrins joined via an intervening bis(dipyrrinato)copper(II) complex. Two porphodimethenatozinc complexes were prepared and found to have Φ f ≤ 0.002 (in toluene at room temperature), which is substantially less than the analogous bis(dipyrrinato)zinc complexes. Taken together, the syntheses described herein should broaden access to dipyrrins for use as complexation motifs in supramolecular chemistry and as pigments in light-harvesting applications.