Novel Cofacial Porphyrin‐Based Homo‐ and Heterotrimetallic Complexes of Transition Metals

Autor: Christoph Schissler, Gereon Niedner-Schatteburg, Manfred M. Kappes, Patrick Weis, Sergei Lebedkin, Erik K. Schneider, Stefan Bräse
Rok vydání: 2021
Předmět:
Zdroj: Chemistry-A European Journal, 27 (61), 15202-15208
Chemistry (Weinheim an Der Bergstrasse, Germany)
ISSN: 1521-3765
0947-6539
Popis: We present a straightforward and generally applicable synthesis route for cofacially linked homo‐ and heterotrimetallic trisporphyin complexes. The protocol encompasses synthesising the first aryl‐based, trans‐o‐phenylene trisporphyrin starting from pyrrole and benzaldehyde with an overall yield of 3.6 %. It also allows investigating the respective cis‐isomer as the first conformationally restricted planar‐chiral trisporphyrin. The free‐base ligand was used in subsequent metalation reactions to afford the corresponding homotrimetallic Mn(III)‐, Fe(III)‐, Ni(II)‐, Cu(II)‐, Zn(II)‐ and Pd(II) complexes – additionally, a small adaptation of the protocol resulted in the defined Ni(II)Fe(III)Ni(II) complex in a total yield of 2.3 %. By monitoring Ni(II) insertion into the empty trimeric ligands, we affirmed that the outer porphyrin rings are filled before the internal ring. The molecular species were characterised by 1H NMR, UV‐Vis, photoluminescence, IR, MS, CID, and high‐resolution IMS measurements.
A synthesis route for cofacially linked homo‐ and heterotrimetallic trisporphyin complexes starting from pyrrole and benzaldehyde is presented in this work. Besides the novel aryl‐based, trans‐o‐phenylene trisporphyrin, we investigated the respective cis‐isomer as the first conformationally restricted planar‐chiral trisporphyrin. The homotrimetallic Mn(III)‐, Fe(III)‐, Ni(II)‐, Cu(II)‐, Zn(II)‐ and Pd(II) complexes and the defined Ni(II)Fe(III)Ni(II) heterotrimetalic complex were synthesized, the metal ion insertion process studied and the resulting compounds investigated by e. g. UV‐Vis, photoluminescence or high‐resolution IMS measurements.
Databáze: OpenAIRE