Synthesis and Characterization of Mono-Isomeric Alkylbenzene Sulfonates

The synthesis of a series of isomer pure mid-position alkylbenzene sulfonates is described. Three isomers—4-(1-ethyldodecyl)benzene sodium sulfonate, 4-(1-butyldecyl)benzene sodium sulfonate, and 4-(1-hexyloctyl)benzene sodium sulfonate—were synthesized. High performance liquid chromatography (HPLC) indicated that the isomers were of 99.9%, 96.2%, and 97.5% purity, respectively. Their structures were characterized to be correct by electrospray ionization-mass spectrometry (ESI-MS), ¹H NMR, and ¹³C NMR investigations. Furthermore, the purity and structure of the three kinds of intermediates were also determined by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS).