Acta Crystallographica Section B

Structural Science

Volume 56, Part 1 (February 2000)

research papers

Acta Cryst. (2000). B56, 124-131 [ doi:10.1107/S0108768199007740 ]

N-n-Alkyl N,N-dimethylammonioacetic acid bromides: the first complete series of crystal and molecular structure determinations of an amphiphilic compound with alkyl chain lengths n = 1,..., 16

R. Rudert, B. Schulz, G. Reck, D. Vollhardt and J. Kriwanek

Abstract: The molecular and crystal structures of 16 N-n-alkyl N,N-dimethylammonioacetic acid bromides with chain lengths between n = 1 and n = 16 have been determined. All compounds from n = 5 to n = 16 form bilayers with interdigitated chains. The even-numbered chains display the chain packing type M₂^II. The chain packing of the odd-numbered chain compounds is less regular. The head groups of all compounds are connected via electrostatic N⁺Br^- interactions, and by OHBr^- hydrogen bonds. The compounds with short chains are packed in different ways. Their molecular conformation depends on the crystal packing.

Keywords: Amphiphilic; Chain packing.