Structure and Reactivity of Organic Cations in the Gas Phase and Condensed Media

University Of California-Riverside, Riverside CA

Investigators

Abstract

This project probes the relationship between the 3-dimensional structure of organic molecules that carry an electric charge and their chemical reactivity. A key objective of this program is to compare the behavior of ions in the gas phase with those in condensed phases. The picture of how ions behave in the gas phase in relation to their behavior in condensed phases remains incomplete, although there are many parallels. Some ions cannot be made in solution and can be explored only in the gas phase, but others can be made under a variety of conditions. Comparison reveals the effects of solvent and of pairing with opposite charges. Broader impacts resulting from the proposed activity Undergraduate instruction plays an important role in disseminating new results. The PI has invested much effort in teaching small sections (beyond his assigned teaching load) to communicate insights from research. Offered through the UC Riverside's Honors' Program, these sections introduce students to hypothesis testing based on conformational analysis and ion chemistry of small molecules. The PI has developed a course in which, from fall 2006 through the end of 2008, approximately 120 sophomores and juniors (of whom >25% are under-represented minorities, including 8 Chicana/o, 9 other Latina/o, 11 Pacific Islander, 3 African American) have been instructed how to perform molecular modeling on a computer independently, with a view towards comparing computed predictions with experimental data. In regard to research publication, development of mass spectrometric methodology for analyzing how bacteria oxidize alkanes is germane to environmental issues regarding worldwide extraction and transportation of petroleum. With respect to peptide mass spectrometry, development of MS/MS methodology for detecting and quantitating amino acid and peptide stereoisomers will make it possible to assess more routinely how widespread post-translational modification via amino acid epimerization may turn out to be in biological systems. In the research laboratories, a major objective is the education of Ph.D. students to combine organic chemistry with instrumental methods.