Hexaphyrin(1.0.1.0.0.0): An Expanded Porphyrin Ligand for the Actinide Cations Uranyl (UO22+) and Neptunyl (NpO2+)

Abstract

Beseitigung von radioaktivem Abfall, egal welchen Ursprungs, ist ein wichtiges Problem, zu dessen Lösung der expandierte Porphyrinligand 1 beitragen könnte: Sowohl mit Uranyl‐ (UO22+) als auch mit Neptunyl‐Ionen (NpO2+) bildet er stabile Komplexe.

Cyclo[8]pyrrole: A Simple-to-Make Expanded Porphyrin with No Meso Bridges

“…Therefore, we decided to concentrate our efforts on a simple one‐pot strategy that would involve the direct coupling of bipyrrolic fragments (Scheme ). Accordingly, several readily available substituted and unsubstituted bipyrroles were subjected to a wide range of potential coupling conditions, such as ones involving condensation of the bipyrrole with SCl 2 and subsequent sulfur extrusion of the putative thia‐bridged macrocyclic intermediates19 as well as various oxidative coupling procedures 13–15, 17, 18, 20–29. Among the latter were the Cr VI ‐based oxidative coupling method described by Falk and Flödl,23 which we have recently found useful in the synthesis of other expanded porphyrins,17, 18 and strategies based on the use of 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) and chloranil—reagents that have been used to prepare a range of expanded13–15, 20–22 and contracted porphyrins 25–29.…”

Cyclo[8]pyrrole: A Simple-to-Make Expanded Porphyrin with No Meso Bridges This work was supported by the National Science Foundation (grant CHE 0107732 to J.L.S.). The authors would like to thank Dr. Paul Fleitz and Weijie Su (Wright Patterson Air Force Base) for recording the UV/Vis spectrum of 2 b.

“…Therefore, we decided to concentrate our efforts on a simple one‐pot strategy that would involve the direct coupling of bipyrrolic fragments (Scheme 1). Accordingly, several readily available substituted and unsubstituted bipyrroles were subjected to a wide range of potential coupling conditions, such as ones involving condensation of the bipyrrole with SCl 2 and subsequent sulfur extrusion of the putative thia‐bridged macrocyclic intermediates19 as well as various oxidative coupling procedures 13–15, 17, 18, 20–29. Among the latter were the Cr VI ‐based oxidative coupling method described by Falk and Flödl,23 which we have recently found useful in the synthesis of other expanded porphyrins,17, 18 and strategies based on the use of 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) and chloranil—reagents that have been used to prepare a range of expanded13–15, 20–22 and contracted porphyrins 25–29.…”

Synthesechemie expandierter Porphyrine

“…Durch ein oxidatives Verknüpfungsverfahren mit Cr VI gelang die Synthese des als Dihydrochlorid 90 isolierten [24]Hexaphyrins(1.0.1.0.0.0),101 eines Isomers von Amethyrin ( 88 ) 99. Die gewünschte Verbindung 90 wurde durch Behandeln der offenkettigen Hexapyrrolvorstufe 89 mit Na 2 Cr 2 O 7 in Trifluoressigsäure, chromatographische Aufarbeitung und nachfolgende Umsetzung mit HCl in 77 % Ausbeute erhalten (Schema ).…”