Self-Sorting Molecular Clips
journal contributionposted on 01.08.2008 by Soumyadip Ghosh, Anxin Wu, James C. Fettinger, Peter Y. Zavalij, Lyle Isaacs
Any type of content formally published in an academic journal, usually following a peer-review process.
We report the synthesis and characterization of 12 C-shaped methylene-bridged glycoluril dimers (1−12) bearing H-bonding groups on their aromatic rings. Compounds 1, 2, (±)-4a, (±)-5, (±)-7, and 8 form tightly associated homodimers in CDCl3, due to the combined driving force of π−π and H-bonding interactions. Compounds 2, (±)-5, and 8, 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 CDCl3. When the spatial distributions of the H-bonding groups of the molecular clips are similar (e.g., 1 and 2), 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., 1, (±)-5, and (±)-7) and even four (2, (±)-5, 9, and 10) components. The potential of molecular clips 1−12 as robust, functionalizable, self-sorting modules to control the noncovalent interaction network in systems chemistry studies is described.