Molecular Crystals and Liquid Crystals, Vol.428, 87-99, 2005
Crystal and molecular structure of 2 : 1 complex of tetradecyltrimethylammonium bromide with Rac-1,1'-bi-2-naphthol
The crystal and molecular structure of 2:1 complex of the tetradecyltrimethyl-ammonium bromide with rac-1,1'-bi-2-naphthol (14TAB/BNP) is reported. The 14TAB/BNP complex crystallizes in monoclinic space group C2/c. The asymmectric unit of the complex consists of two crystallographically independent molecules of 14TAB and one ctystallographically independent molecule of BNP. Die crystal structure of the complex is stabilized by mainly the intermolecular hydrogen bonding between the bromide anions and OH groups of BNP. The molecules are held in their aggregates by Ol...Br2, 3.220(4) angstrom and O2...Br1, 3.161 (4) angstrom hydrogen. bonding. The crystal-structure studies revealed that one of the alkyl chains has an all trans conformation, whereas the second alkyl chain does not have all trans conformation but has at least a gauche conformation. The packing structure is unique and different from those observed in complexes of monoalkyltrimethyl-ammonium halides with planar aromatic molecules as well as those of 1:1 complexes of monoalkyltrimethylammonium with nonplanar aromatic molecules. The manner in. which the 14TAB molecules lay parallel to the naphthol moieties are similar to that observed in 2:1 complex of 10TAB/BNP.