meso-Pyrimidinyl-Substituted A₂B-Corroles

Abstract

meso-Pyrimidinyl-substituted A2B-corroles were synthesized in good yields by condensation of 5-mesityldipyrromethane and 2-substituted 4,6-dichloropyrimidine-5-carbaldehydes. A simple reduction of the amount of Lewis acid (BF3.OEt2) resulted in the formation of A2B-corroles, which was optimized to maximize the corrole yield. Nucleophilic aromatic substitution, Suzuki, and Stille cross-coupling reactions were performed on the Cu-metalated pyrimidinylcorroles to obtain sterically encumbered triarylcorroles, while the substitution pattern at the 2-position of the pyrimidinyl substituent was altered through Liebeskind-Srogl cross-couplings.

Synthetic, Structural, and Photophysical Exploration of meso‐Pyrimidinyl‐Substituted AB2‐Corroles

“…[8,9] Within one of our research groups, we have been studying the synthesis and reactivity of 4,6-dichloropyrimidines as versatile structural building blocks for meso-pyrimidinylsubstituted porphyrins, [10] heteracalix [m]arene [m]pyrimidines, [11] and pyrimidine-based (porphyrin) dendrimers. [12,13] During the course of our studies on pyrimidinylporphyrins, it was discovered that a slight modification of the reaction conditions, as optimized for porphyrins, results in the formation of either expanded (penta-and hexaphyrins) [14] or contracted [15] porphyrin analogues. The major advantage concerning the introduction of dichloropyrimidinyl moieties on the meso positions of a porphyrinoid macrocycle is the wide scope of functionalization reactions that can be performed on the dichloropyrimidine units.…”

“…[10,14] In previous communications, specific synthetic aspects of pyrimidinylcorroles have been described. [9,[15][16][17] In this paper, we report a detailed multidisciplinary study on the synthesis and functionalization, structural elucidation and photophysical properties of meso-pyrimidinyl-substituted AB 2 -corroles (A = 4,6-dichloropyrimidin-5-yl). [18] Results and Discussion Synthesis of the AB 2 -pyrimidinylcorrole scaffold: In 2001, one of our groups contributed to the early stages of synthetic corrole chemistry by exploring the synthesis of sterically encumbered triarylcorroles starting from aromatic aldehydes and 5-aryldipyrromethanes.…”

“…[15] As a first step towards variation of the pyrimidinylcorrole periphery, the possibility to synthesize AB 2 -corroles starting from 2 b and various 2-substituted 4,6-dichloropyrimidine-5-carbaldehydes 1 b-d was explored. Mesityldipyrromethane was chosen for reasons of availability and solubility of the final corrole, and it can easily be prepared through a recently optimized procedure that allows one to obtain aryldipyrromethanes in high yields by simple precipitation from an acidic aqueous solution.…”

“…The AB 2 -corroles had to be chromatographically separated from the concurrently formed A 2 B 2 -porphyrins. [15] The amount of Lewis acid catalyst appeared to be a crucial parameter to obtain either the meso-pyrimidinyl-substituted AB 2 -corrole or the A 2 B 2 -porphyrin as the major product. Hence, an optimization study of the BF 3 ·OEt 2 content was performed to maximize the corrole yield.…”

Determination of interaction strength between corrole and phenol derivatives in aqueous media using atomic force microscopy

“…Corrole was synthesized at the Department of Chemistry (University of Leuven) using method [37][38][39] as described below: and SH), ~ -1.9 (br. s, 3H, NH); δ C 158.…”