10.1021/ja067571x.s010 Kenneth E. Maly Kenneth E. Maly Eric Gagnon Eric Gagnon Thierry Maris Thierry Maris James D. Wuest James D. Wuest Engineering Hydrogen-Bonded Molecular Crystals Built from Derivatives of Hexaphenylbenzene and Related Compounds American Chemical Society 2007 core compound 4 crystallizes molecule hexaphenylbenzene diaminotriazine groups unsubstituted phenyl groups Analogue 2007-04-11 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Engineering_Hydrogen_Bonded_Molecular_Crystals_Built_from_Derivatives_of_Hexaphenylbenzene_and_Related_Compounds/3013600 Hexakis[4-(2,4-diamino-1,3,5-triazin-6-yl)phenyl]benzene (<b>4</b>) incorporates a disc-shaped hexaphenylbenzene core and six peripheral diaminotriazine groups that can engage in hydrogen bonding according to established motifs. Under all conditions examined, compound <b>4</b> crystallizes as planned to give closely related noninterpenetrated three-dimensional networks built from sheets in which each molecule has six hydrogen-bonded neighbors. In the structure of compound <b>4</b>, the number of hydrogen bonds per molecule and the percentage of volume accessible to guests approach the highest values so far observed in molecular networks. Analogue <b>5</b> (which has the same hexaphenylbenzene core but only four diaminotriazine groups at the 1,2,4,5-positions) and analogue <b>7</b> (in which the two unsubstituted phenyl groups of compound <b>5</b> are replaced by methyl groups) crystallize according to a closely similar pattern. Analogues with flatter pentaphenylbenzene or tetraphenylbenzene cores crystallize differently, underscoring the importance of maintaining a consistent molecular shape in attempts to engineer crystals with predetermined properties.