Preparation of tricationic tris(pyridylpalladium(ii)) metallacyclophane as an anion receptor†
Hiroshi Danjo,Kohei Asai,Tomoya Tanaka,Daiki Ono,Masatoshi Kawahata,Satoshi Iwatsuki
Chemical Communications Pub Date : 01/24/2022 00:00:00 , DOI:10.1039/D1CC05563A
Abstract

A tricationic tris(pyridylpalladium(II)) metallacyclophane was prepared from 3,5-dibromopyridine by a successive treatment with tetrakis(triphenylphosphine)palladium(0), diphosphine, and silver salt. Single-crystal X-ray diffraction analysis revealed that the metallacyclophane incorporated one of three counter anions into its hole-shaped cavity to form multidentate C–H⋯anion interactions. Solution-phase 1H NMR experiments in DMSO-d6 indicated that the metallacyclophane exhibited selective binding behavior toward nitrate, tetrafluoroborate, p-toluenesulfonate, perchlorate, and hydrogen sulfate ions, whereas the hexafluoroantimonate ion exhibited only weak interaction toward the metallacyclophane. This anion recognition behavior was further demonstrated by an extraction experiment of water-soluble sulfonate dyes.

Graphical abstract: Preparation of tricationic tris(pyridylpalladium(ii)) metallacyclophane as an anion receptor