Hydrogen-bonded molecular aggregates

Seto, C. T., and Whitesides, G. M., Molecular self-assembly through hydrogen bonding supramolecular aggregates based on the cyanuric acid melamine lattice, J. Am. Chem. Soc., 115, 905-916 (1993). 

The rates of intermolecular Diels-Alder reactions of hydrophobic dienes and dienophiles are significantly increased when the cycloadditions are performed in pure ethylene glycol (EG) [49a]. Some examples are illustrated in Scheme 6.30. This performance is due to the fact that the EG (i) forms extensive hydrogen bonding, (ii) is able to solubilize hydrophobic dienes and dienophiles, and (hi) forms molecular aggregations with the reactants. 

In the transmission electron microscopy (TEM) images, the starch nanoplatelets (SNPs) are believed to aggregate as a result of hydrogen bond interactions due to the surface hydroxyl groups [13] (Fig. lA). Blocking these interactions by relatively large molecular weight molecules obviously improves the individualization of the nanoparticles. The acetylated starch and cellulose nanoparticles (SAcNPs and CelAcNPs) appeared more individualized and monodispersed than their unmodified counterparts with a size of about 50 nm (Fig. IB C). 

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