Organization of the enantiomeric and racemic forms of an amphiphilic resorcinol derivative at the air-water and graphite-1-phenyloctane interfaces

TitleOrganization of the enantiomeric and racemic forms of an amphiphilic resorcinol derivative at the air-water and graphite-1-phenyloctane interfaces
Publication TypeJournal Article
Year of Publication2012
AuthorsIavicoli, P, Xu, H, Keszthelyi, T, Telegdi, J, Wurst, K, Van Averbeke, B, Saletra, WJ, Minoia, A, Beljonne, D, Lazzaroni, R, De Feyter, S, Amabilino, DB
JournalChirality
Volume24
Pagination155–166
ISSN1520-636X
Keywordsconglomerate, lactate, langmuir, molecular modeling, SAM, SFG, spontaneous resolution, STM
Abstract

This article describes a study of the outcome of racemate condensation in different types of monolayers. The study was performed on a resorcinol surfactant bearing an octadecyl chain and a lactate group which formed a monolayer at the interface of graphite and 1-phenyloctane as well as a Langmuir film at the air-water interface. Control experiments with the enantiopure materials provided the characteristics of the chiral organizations. The results obtained on the racemate show that on graphite the molecule forms chiral domains, indicating that spontaneous resolution takes place at the surface, a phenomenon that has been rationalized using molecular modeling. The X-ray crystal structure of the DMSO solvate of one of the enantiomers shows a similar type of packing to this monolayer. On the other hand, in the Langmuir layer it appears that the formation of a racemic compound is favoured, as it is in the solid state in three dimensions. The work shows how the symmetry restrictions in different environments can have a critical influence on the outcome of racemate organization, and underline the tendency of graphite to favour symmetry breaking in monolayers formed at its surface. Chirality, 2012. © 2011 Wiley Periodicals, Inc.

URLhttp://dx.doi.org/10.1002/chir.21976
DOI10.1002/chir.21976