ON THE CONFORMATION OF TRIETHANOLAMINE AND THE TRIETHANOLAMMONIUM ION- THE CRYSTAL-STRUCTURE OF TRIETHANOLAMMONIUM BROMIDE

The crystal structure of triethanolammonium bromide is reported. The c ompound is completely isostructural with the Cl- and the SH- salts. Th e triethanolamine moieties in all known crystal structures invariably have endo conformation. Quantum chemical calculations were carried out to investigate possible crystal packing effects. Optimized geometries were computed for various structural models to establish conformation s for the free molecules. The results confirmed that the endo conforma tion is the most stable regardless of protonation and crystal packing. This conformation makes triethanolamine an ideal agent to form cage c ompounds (atranes) in trans-esterification reactions.