Intramolecular Hydrogen Bonding Effects on the Reversed-Phase Retention of Substituted Acetophenones

Abstract

Reversed-phase 1 iquid chromatography (RPLC) is widely recognized as a valuable technique for the separation of compounds of varying 1 ipophil ic/hydrophobic nature. RPLC on hydrocarbon stationary phases has been used for the separation of homologues of various compound classes with outstanding success (1–3). Excellent correlations have been obtained between RPLC capacity factors and various parameters of the solvophobic theory (4–6). This theory suggests that solute-solvent interactions assume the primary role in the RPLC retention process (7–9). The creation of a suitable cavity in the mobile phase is a key factor affecting the retention of the solute. The size and shape of the cavity formed in the solvent depends on solute molecular volume and hydrophobic surface area as well as the dielective constant and surface tension of the solvent. Relationships between RPLC capacity factors, partition coefficients (10,ll) and biological activities (12) have been reported. These high correlations suggest RPLC can be a very useful tool for the study of molecular phenomena in solution.