A gold-nanoparticle stoppered [2]rotaxane
Journal article, 2018

The construction of molecular machines has captured the imagination of scientists for decades. Despite significant progress in the synthesis and studies of the properties of small-molecule components (smaller than 2-5 kilo Dalton), challenges regarding the incorporation of molecular components into real devices are still eminent. Nano-sized molecular machines operate the complex biological machinery of life, and the idea of mimicking the amazing functions using artificial nano-structures is intriguing. Both in small-molecule molecular machine components and in many naturally occurring molecular machines, mechanically interlocked molecules and structures are key functional components. In this work, we describe our initial efforts to interface mechanically-interlocked molecules and gold-nanoparticles (AuNPs); the molecular wire connecting the AuNPs is covered in an insulating rotaxane-layer, thus mimicking the macroscopic design of a copper wire. Taking advantage of recent progress in the preparation of supramolecular complexes of the cucurbit[7]uril (CB[7] ) macrocycle, we have prepared a bis-thiol functionalised pseudo-rotaxane that enables us to prepare a AuNP-stoppered [2]rotaxane in water. The pseudo-rotaxane is held together extremely tightly (K a > 10 13 M -1 ), K a being the association constant. We have studied the solution and gas phase guest-host chemistry using NMR spectroscopy, mass spectroscopy, and electrochemistry. The bis-thiol functionalised pseudo-rotaxane holds further a ferrocene unit in the centre of the rotaxane; this ferrocene unit enables us to address the system in detail with and without CB[7] and AuNPs using electrochemical methods.

Author

Anne Ulfkjær

University of Copenhagen

Frederik W. Nielsen

University of Copenhagen

Hana Al-Kerdi

University of Copenhagen

Tamara Ru

University of Copenhagen

Zaki K. Nielsen

University of Copenhagen

J. Ulstrup

Technical University of Denmark (DTU)

LU SUN

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry, Physical Chemistry

Kasper Moth-Poulsen

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Kasper Moth-Poulsen Group

Jingdong Zhang

Technical University of Denmark (DTU)

M. Pittelkow

University of Copenhagen

Nanoscale

2040-3364 (ISSN)

Vol. 10 19 9133-9140

Subject Categories

Physical Chemistry

Other Chemistry Topics

Organic Chemistry

DOI

10.1039/c8nr01622d

More information

Latest update

5/29/2018