Porous networks based on iron(ii) clathrochelate complexes

Abstract

Microporous networks based on boronate ester-capped iron(II) clathrochelate complexes are described. The networks were obtained by covalent cross-linking of tetrabrominated clathrochelate complexes via Suzuki–Miyaura polycross-coupling reactions with diboronic acids, or by Sonogashira–Hagihara polycross-coupling of clathrochelate complexes with terminal alkyne functions and 1,3,5-tribromobenzene. The networks display permanent porosity with apparent Brunauer–Emmett–Teller surface areas of up to SA_BET = 593 m² g⁻¹. A clathrochelate complex based on an enantiopure dioximato ligand was used to prepare chiral networks. One of these networks was shown to preferentially absorb D-tryptophan over L-tryptophan.