Control of the cavity size of flexible covalent cages by silver coordination to the peripheral binding sites.

Lucas Kocher,Valérie Heitz,Stéphanie Durot

doi:10.1039/c5cc04972e

Abstract

The synthesis of covalent cages consisting of two porphyrins connected by four flexible spacers each incorporating two 1,2,3-triazolyl ligands is reported. Binding of four silver(I) to the peripheral ligands induces conformational changes in solution and locks the porphyrins in a face-to-face disposition.

Highlights

The synthesis of covalent cages consisting of two porphyrins connected by four flexible spacers each incorporating two 1,2,3triazolyl ligands is reported
With the aim of building multicomponent flexible porphyrin containers with orthogonal binding sites, we have reported the synthesis of porphyrinic covalent cages with eight 3-pyridyl ligands thanks to a DABCO-templated ring-closing metathesis reaction (DABCO: 1,4-diazabicyclo[2.2.2]octane).[8]
It was envisioned to use the distal coordination sites incorporated in flexible porphyrin containers to adjust their cavity size

Summary

Introduction

The synthesis of covalent cages consisting of two porphyrins connected by four flexible spacers each incorporating two 1,2,3triazolyl ligands is reported. Binding of four silver(I) to the peripheral ligands induces conformational changes in solution and locks the porphyrins in a face-to-face disposition. We describe the synthesis of a covalent and flexible zinc(II) porphyrinic cage 1 and its metal-free analogue 2 that incorporate eight 1,2,3-triazolyl ligands as peripheral coordination sites, based on a DABCO-templated CuAAC reaction.

Results

Conclusion