Tetrathiafulvalene mono- and bis-1,2,3-triazole precursors by click chemistry: structural diversity and reactivity

Thomas Biet,Narcis Avarvari

doi:10.1039/c4ob00148f

Abstract

The donor ortho-dimethyl-TTF-(N-n-Bu-1,2,3-triazole) 1,5-isomer has been synthesized by click chemistry following a ruthenium-catalyzed azide-alkyne cycloaddition procedure. The single crystal X-ray analysis showed a planar conformation between the TTF and triazole units and a set of intermolecular interactions at the supramolecular level in the solid state. The same procedure allowed the preparation of the corresponding ortho-dimethyl-TTF-bis(triazole) which was also structurally characterized. Because of the steric hindrance, the triazole units are no longer planar with the TTF backbone. The reactivity of the triazole ring has been investigated in protonation and alkylation reactions, monitored by UV-visible spectroscopy, which clearly showed the red shift of the intramolecular charge transfer band. A TTF-methyl-triazolium salt has been isolated and analyzed by single crystal X-ray analysis. All of the TTF-triazoles and triazolium salts are valuable precursors for radical cation salts due to their oxidation potentials and variety of possible intermolecular interactions.

Highlights

Synthetic methods based on click chemistry strategies have developed increasingly over the last decade,[1] with one of the most useful reactions being the copper-catalyzed azide–alkyne cycloaddition (CuAAC) that allows the straightforward preparation of 1,2,3-triazoles (1,4-isomers).[2]
The 1,5-isomers of 1,2,3-triazoles have been efficiently prepared by the azide–alkyne cycloaddition mediated by a ruthenium(II)-based catalyst.[6]
We report the synthesis, reactivity and solid state structures of TTF-mono and -bis(1,2,3-triazoles), together with those of a TTF-triazolium salt

Summary

Introduction

Synthetic methods based on click chemistry strategies have developed increasingly over the last decade,[1] with one of the most useful reactions being the copper-catalyzed azide–alkyne cycloaddition (CuAAC) that allows the straightforward preparation of 1,2,3-triazoles (1,4-isomers).[2]. We report the synthesis, reactivity and solid state structures of TTF-mono and -bis(1,2,3-triazoles), together with those of a TTF-triazolium salt.

Results

Conclusion