The Power of Nonconventional Phenyl C--H...N Hydrogen Bonds: Supportive Crystal-Packing Force and Dominant Supramolecular Engineering Force
The role of phenyl C-H...N interactions in crystal engineering is explored with a variety of fluorinated phenyl-containing compounds. In particular, we show that this interaction can guide the formation of one-dimensional phenyl C-H...N hydrogen-bonded ribbons with, for example, 4-(2,3,5,6-tetrafluorophenylethynyl)pyridine. The interaction is shown to also control the formation of self-complementary homodimers with 3-(2,3,4,5-tetrafluorophenylethynyl)pyridine. We also demonstrate that the phenyl C-H...N hydrogen bond interaction is capable of enticing co-crystallization of molecules such as 2,3,5,6,2"²,3"²,5"²,6"²-octafluorobiphenyl and 4,4"²-dipyridyl. Finally, we describe the use of an intramolecular scaffold to evaluate the effect of electron-withdrawing substituents on the strength of a phenyl C-H...N hydrogen bond.
Bosch, Eric, Nathan P. Bowling, and Jeffery Darko. "The power of nonconventional phenyl C–H··· N hydrogen bonds: Supportive crystal-packing force and dominant supramolecular engineering force." Crystal Growth & Design 15, no. 4 (2015): 1634-1641.
Crystal growth & design