Crystal structures of two isomers of 1-(naphthalen-1-yl)ethanol.

Crystal structures, Hirshfeld surfaces and energy lattices of (S)-1-(naphthalen-1-yl)ethanol (1) and (R)-1-(naphthalen-2-yl)ethanol (2), both C12H12O, were studied to understand much the lower crystallization propensity of the latter. In both structures, mol-ecules are linked by strong hydrogen bonds into helical chains where Coulombic inter-actions expectedly dominate, but dispersive inter-actions of 1 and 2 differ significantly, resulting in large gaps in the total energy lattice of 2. The poor crystallization and and higher Z' (4 vs 2 in structure 1) of 2 can be explained by frustration between supra-molecular synthons (⋯O-H⋯O-H⋯ hydrogen-bonding chain vs π-π- inter-actions between naphthalene moieties). The study provides new insights into the supra-molecular inter-actions and crystal packing of regioisomeric naphthalenyl-ethanol compounds, which may have implications for the design of new materials with tailored properties.