The Synthesis of Functionalised Diaryltetraynes and Their Transport Properties in Single-Molecule Junctions

Gulcur, M.; Moreno-García, P.; Zhao, X.; Baghernejad, M.; Batsanov, A.S.; Hong, W.; Bryce, M.R.; Wandlowski, T.

Abstract

The synthesis and characterisation is described of six diaryltetrayne derivatives [Ar-(C[TRIPLE BOND]C)4-Ar] with Ar=4-NO2-C6H4- (NO24), 4-NH(Me)C6H4- (NHMe4), 4-NMe2C6H4- (NMe24), 4-NH2-(2,6-dimethyl)C6H4- (DMeNH24), 5-indolyl (IN4) and 5-benzothienyl (BTh4). X-ray molecular structures are reported for NO24, NHMe4, DMeNH24, IN4 and BTh4. The stability of the tetraynes has been assessed under ambient laboratory conditions (20 °C, daylight and in air): NO24 and BTh4 are stable for at least six months without observable decomposition, whereas NHMe4, NMe24, DMeNH24 and IN4 decompose within a few hours or days. The derivative DMeNH24, with ortho-methyl groups partially shielding the tetrayne backbone, is considerably more stable than the parent compound with Ar=4-NH2C6H4 (NH24). The ability of the stable tetraynes to anchor in Au|molecule|Au junctions is reported. Scanning-tunnelling-microscopy break junction (STM-BJ) and mechanically controllable break junction (MCBJ) techniques are employed to investigate single-molecule conductance characteristics.

Citation

Gulcur, M., Moreno-García, P., Zhao, X., Baghernejad, M., Batsanov, A., Hong, W., …Wandlowski, T. (2014). The Synthesis of Functionalised Diaryltetraynes and Their Transport Properties in Single-Molecule Junctions. Chemistry - A European Journal, 20(16), 4653-4660. https://doi.org/10.1002/chem.201304671

• Journal Article Type: Article
• Publication Date: Apr 1, 2014
• Deposit Date: Nov 24, 2014
• Publicly Available Date: Nov 26, 2014
• Journal: Chemistry - A European Journal
• Print ISSN: 0947-6539
• Electronic ISSN: 1521-3765
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 20
• Issue: 16
• Pages: 4653-4660
• DOI: https://doi.org/10.1002/chem.201304671
• Keywords: Cross-coupling, Oligoynes, Polyynes, Single-molecule conductance, X-ray diffraction.
• Public URL: https://durham-repository.worktribe.com/output/1419470