Using Systematic Comparisons of 2D and 3D Structures To Reveal Principles of Molecular Organization. Tetraesters of Linear Bisisophthalic Acids

Abstract

Linear bisisophthalic acids <b>1</b> and <b>2</b> and analogous structures are known to be adsorbed on graphite to give nanopatterns that are programmed by the concerted effects of topology and hydrogen bonding. For comparison, we have now studied the corresponding tetraesters <b>3</b>–<b>7</b>, which have similar topologies and affinities for graphite but cannot form strong intermolecular interactions. As a result, they fail to crystallize in 2D and 3D according to consistent patterns. The sharply contrasting behavior of the tetraacids and tetraesters provides compelling evidence for the hypothesis that molecular organization is best controlled in both 2D and 3D by using topology and strong directional interactions in tandem to control the relative orientation of neighbors. When topology and dominant intermolecular interactions are in harmony, then organization can be expected to follow reliable patterns within a related series of compounds, and structures in 2D and 3D can be designed to show high levels of homology