title: Search of nature of planar chirality for pendent benzodiazacoronands in the solid state: NMR, X-ray, and DFT studies.
abstract: In this work, we report the structural studies on the solid state of two benzodiazacoronads that form chiral and achiral crystals. Crystals have to be considered as a two-component system consisting of an organic unit and a water molecule in 1:1 ratio. Both components play an important role in the crystal structure. The strong (O-H...O, N-H...O) and weak (C-H...O) intermolecular hydrogen bonds are responsible for phase organization and, in consequence, formation of chiral or achiral crystals. The alignment of the water molecule with respect to the macrocycle is different for samples 1 and 2. Removal of water from the crystal lattice of 1 is reversible. Formation of chiral cocrystals from two different achiral molecules by self-assembly is well-known. However, in this paper, we show that the water molecule can be an important achiral cofactor responsible for chiral crystallization.
authors.affiliation: Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland.
authors.forename: Justyna
authors.initials: J
authors.lastname: Pacholczyk
authors.forename: Jarosław
authors.initials: J
authors.lastname: Kalisiak
authors.forename: Janusz
authors.initials: J
authors.lastname: Jurczak
authors.forename: Marek J
authors.initials: MJ
authors.lastname: Potrzebowski