Self-Sorting Molecular Clips
2008-08-01T00:00:00Z (GMT) by
We report the synthesis and characterization of 12 C-shaped methylene-bridged glycoluril dimers (<b>1</b>−<b>12</b>) bearing H-bonding groups on their aromatic rings. Compounds <b>1</b>, <b>2</b>, (±)-<b>4a</b>, (±)-<b>5</b>, (±)-<b>7</b>, and <b>8</b> form tightly associated homodimers in CDCl<sub>3</sub>, due to the combined driving force of π−π and H-bonding interactions. Compounds <b>2</b>, (±)-<b>5</b>, and <b>8</b>, having disparate spatial distribution of their H-bonding groups, display the ability to efficiently distinguish between self and nonself even within three-component mixtures in CDCl<sub>3</sub>. When the spatial distributions of the H-bonding groups of the molecular clips are similar (e.g., <b>1</b> and <b>2</b>), a mixture of homodimers and heterodimers is formed. The effect of various structural modifications (e.g., chirality, side chain steric bulk, number and pattern of H-bonds) on the strength of self-assembly and the fidelity of self-sorting are presented. On the basis of these results we prepared self-sorting systems comprising three (e.g., <b>1</b>, (±)-<b>5</b>, and (±)-<b>7</b>) and even four (<b>2</b>, (±)-<b>5</b>, <b>9</b>, and <b>10</b>) components. The potential of molecular clips <b>1</b>−<b>12</b> as robust, functionalizable, self-sorting modules to control the noncovalent interaction network in systems chemistry studies is described.