Isolation of Phlorin-Dipyrrin Conjugates from the Acid-Catalyzed Condensation of Dipyrromethanes and Aldehydes
The product distribution of the acid-mediated condensation of dipyrromethanes and aldehydes was studied and a novel type of macrocycle phlorin-dipyrrin conjugate was isolated and identified by X-ray analysis. The generality of its formation from sterically hindered dipyrromethanes and pentafluorophenyldipyrromethane was demonstrated. The influence of the meso-aryl groups on the stability of the phlorin was studied. The reported two-step synthesis of a phlorin derivative is one of the simplest routes leading to this type of molecules. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)