A Scalable Synthesis of Meso-Substituted Dipyrromethanes

Abstract

A one-flask synthesis of meso-substituted dipyrromethanes has been refined. The procedure entails reaction of an aldehyde in 100 equiv of pyrrole as the solvent containing a mild Lewis acid (e.g., InCl 3 ) at room temperature. Following removal and recovery of excess pyrrole, the dipyrromethane is obtained by crystallization. The procedure generates minimal waste and does not require aqueous/organic extraction, chromatography, or distillation. The procedure has been scaled linearly to obtain >100 g of 5-phenyldipyrromethane. The utility of various analytical methods for characterizing dipyrromethanes has been investigated.

Bioconjugatable Porphyrins Bearing a Compact Swallowtail Motif for Water Solubility

“…Following a standard procedure (40), aldehyde 6a (2.07 g, 8.78 mmol) was dissolved in dry pyrrole (56.0 mL, 880 mmol), and the solution was flushed with argon for 10 min. InCl 3 (666 mg, 0.800 mmol) was added, and the reaction was allowed to proceed for 3 h. The reaction was quenched by addition of powdered NaOH (977 mg, 24.4 mmol).…”

Study of Structure−Properties Relationship for Lanthanide Tetrapyrrolic Macrocycles Modified with Aminopolycarboxylate Substituents

“…[12,13] 5-(Pentafluorophenyl)-dipyrromethane (DPM) was synthesized accordingly to the reaction. [14] Synthesis of H 3 tpfc (12) was carried out according to the most convenient method for the preparation. [15] Purity of the obtained compounds was checked by TLC Sorbfil plates (grain 5-17 μm, UV-254, thickness 0.1 mm) by Imid Ltd. ).…”

Crystal structure of (5,15-cis-bis(2-hydroxy-1-naphthyl)-10-phenyl-20-(4-hydroxyphenyl)-porphyrinato)-(pyridine)-zinc(ii) pyridine solvate, C67H47N7O3Zn

“…Dipyrromethane [1], 2-methoxy-1-naphthylboronic acid [2] and n-hexadecyloxyl benzaldehyde [3] were prepared according to the published procedures. All other reagents and solvents were used as received.…”