Hexyltrimethylammonium Bromide Inclusion Complex With Rac-1,1′-Bi-2-Naphthol

Abstract

The crystal structure of 1:1 inclusion complex of hexyltrimethylammonium bromide (6TAB) and rac-1, 1′-bi-2-naphthol (BNP) was analysed by the X-ray diffraction method. It was shown that the bromide anion participates in a hydrogen bond with one of the OH groups of BNP (Ol···Br, 3.22(1)Å). The bromide anion also plays a role as the hydrogen acceptor of the OH group of the water molecule (OW···Br, 3.21(3)Å). A strong hydrogen bond was found between the other OH group of BNP and oxygen of the water molecule (O2···OW, 2.63(3)Å). The short C-H···C distances between hydrogen atoms of the alkyl chain together with the methyl groups and carbon atoms of the aromatic rings suggested C-H···π interactions. The atomic distances shorter than the sum of the van der Waals radius (2.97Å) were C10···H6 2.85Å, C14···H9 2.83Å, and C16···H11 2.88Å. The X-ray powder diffraction studies on the complex suggested that the complex crystals can be obtained by crystallization from the solution and also by mixing powdered samples in a mortar.

Key Words:

• Hexyltrimethylammonium bromide
• Inclusion complex
• Racemic compound
• Crystal structure
• Non-planar aromatic
• Molecular interactions