Spectroscopic investigation of hydrogen atom transfer in the McLafferty rearrangement

Loading...
Thumbnail Image
Authors
Kerstetter, Dale R.
Leavitt, Christopher M.
Groenewold, Gary S.
Steill, Jeffrey D.
Oomens, Jos
Van Stipdonk, Michael J.
Advisors
Issue Date
2008-04-25
Type
Conference paper
Keywords
Research Projects
Organizational Units
Journal Issue
Citation
Kerstetter, Dale R., Leavitt, Christopher M., Groenewold, Gary S. (2008). Spectroscopic investigation of hydrogen atom transfer in the McLafferty rearrangement. In Proceedings: 4th Annual Symposium: Graduate Research and Scholarly Projects. Wichita, KS: Wichita State University, p.11-12
Abstract

In this study, wavelength-selective infrared multiple-photon photodissociation (WS-IRMPD) was used to study the transfer of an H atom in a gas-phase unimolecular rearrangement reaction. The reaction studied was the McLafferty rearrangement, which involves transfer of a γ-position hydrogen atom to a carbonyl oxygen atom through a cyclic intermediate, followed by the elimination of an alkene. The IRMPD experiment allows for the collection of vibrational spectra of discrete gasphase ions, which can then be compared to those predicted using density functional theory calculations to assign accurate composition and structure. For the experiment, the tert-butyl ester of a model peptide, nicotinic acid-glycine, was incubated in a mixture of deuterium oxide and deuterated methanol. This solution was the used to make ions by electrospray ionization. The McLafferty rearrangement was then induced by collision-induced dissociation. Following rearrangement, the product ion, consisting of the model peptide with 2 deuterium atoms and 1 H atom in exchangeable sites, was investigated by IRMPD. The infrared spectrum produced clearly shows that the H atom is transferred to the C-terminal acid group and no migration to amide positions occurs on the time scale of the experiment.

Table of Contents
Description
Paper presented to the 4th Annual Symposium on Graduate Research and Scholarly Projects (GRASP) held at the Hughes Metropolitan Complex, Wichita State University, April 25, 2008.
Research completed at the Wichita State University, Department of Chemistry, Fairmount College of Liberal Arts and Sciences bIdaho National Laboratory, Idaho Falls, ID, USA cFOM Instituut voor Plasmafysica, Nieuwigein, The Netherlands
Publisher
Wichita State University. Graduate School.
Journal
Book Title
Series
GRASP
v.4
PubMed ID
DOI
ISSN
EISSN