Supramolecular chiral host-guest nanoarchitecture induced by the selective assembly of barbituric acid derivative enantiomers

Nanotechnology. 2016 Oct 21;27(42):42LT01. doi: 10.1088/0957-4484/27/42/42LT01. Epub 2016 Sep 13.

Abstract

Barbituric acid derivatives are prochiral molecules, i.e. they are chiral upon adsorption on surfaces. Scanning tunneling microscopy reveals that barbituric acid derivatives self-assemble into a chiral guest-host supramolecular architecture at the solid-liquid interface on graphite. The host nanoarchitecture has a sophisticated wavy shape pattern and paired guest molecules are nested insides the cavities of the host structure. Each unit cell of the host structure is composed of both enantiomers with a ratio of 1:1. Furthermore, the wavy patterns of the nanoarchitecture are formed from alternative appearance of left- and right-handed chiral building blocks, which makes the network heterochiral. The functional guest-host nanoarchitecture is the result of two-dimensional chiral amplification from single enantiomers to organizational heterochiral supramolecular self-assembly.