» Research Group web page		John Baldwin  Distinguished Professor Organic chemistry and physical organic chemistry; stereochemistry and mechanisms of thermal reactions of simple hydrocarbons jbaldwin@syr.edu phone: 315-443-3743 / fax: 315-443-4070 Office: CST 4-014B Education: • A.B., 1959, Dartmouth College • Ph.D., 1963, California Institute of Technology Honors & Awards: • William R. Kenan Jr. Professor of Science, Daniel Webster National   Fellow, The Charles Lathrop Parsons Scholar, National Science   Foundation Predoctoral Fellow, Alfred P. Sloan Fellow, John Simon   Guggenheim Memorial Foundation Fellow, Senior U.S. Scientist Awardee   of the Alexander von Humboldt Foundation Courses: • CHE 275: Organic Chemistry • CHE 675*: Advanced Organic Chemistry • CHE 685: Organic Mechanisms   * denotes current Fall '08 course

Research Interests Detailed investigations of chemical transformations provide insights on just how molecules may be converted into other structures. Through determinations of reaction rates, activation parameters, product distributions, kinetic isotope effects, definitions of reaction stereochemistry, and explicit analyses of complex kinetic situations, new data and specific tests of alternative mechanistic interpretations of archetypal thermal reactions lead to better understandings of just how they take place and stimulate theory-based efforts toward similar goals. The degenerate interconversions of deuterium-labeled bicyclo[3.1.0]hex-2-enes provide an clear instance of stereochemical outcomes conditioned by the dynamic behavior of diradical reaction intermediates rather than by distinct energy barriers. Recent work on vinylcyclopropane to cyclopentene isomerizations and thermal rearrangements of 1-(E)-propenyl-2-methylcyclobutanes to 3,4-dimethylcyclohexenes has demonstrated that the reactions take place through conformationally flexible short-lived diradical intermediates. A deuterium-labeling kinetic experiment has shown that bicyclo[4.2.0]oct-7-ene is converted to cis,cis-cyclooctadiene through a direct disrotatory process. Another labeling study utilizing both carbon-13 and deuterium has uncovered an isomerization of cyclopropane to 1-propylidene. Such studies and findings, and related theory-based developments seeking to test and extend the mechanistic perceptions prompted by the experimental results, serve to deepen understandings of chemical reactivity. Whenever such experimental studies are forced to deal with some novel challenge presented by inherent kinetic complexities or extreme analytical requirements or demanding labeling schemes and synthetic requisites, the work also contributes to augmented appreciations of new tools mechanistic organic chemistry can apply to ferret out the not-so-obvious characteristics of chemical reactions. Partial representations of kinetic complexities associated with thermal isomerizations of bicyclo[3.1.0]hex-2-enes and substituted vinylcyclobutanes Selected Publications John E. Baldwin and Phyllis A. Leber, Molecular Rearrangements Through Thermal [1,3] Carbon Shifts. Org. Biomol. Chem. 2008, 6, 36-47. John E. Baldwin, Organic Chemical Reaction Mechanisms Clarified for Deuterium and Carbon-13 Labeled Hydrocarbons, J. Label. Compd. Radiopharm. 2007, 50, 947-960. John E. Baldwin, Anuradha S. Raghavan, B. Andes Hess, Jr., and Lidia Smentek, Thermal [1,5] Hydrogen Sigmatropic Shifts in cis,cis-Cyclonona-dienes Probed by Gas-Phase Kinetic Studies and Density Functional Theory Calculations, J. Am. Chem. Soc. 2006, 128, 14854-14862. John E. Baldwin, Phyllis A. Leber, and David C. Powers, Thermal Reactions of 7-d- and 8-d-Bicyclo[4.2.0]oct-2-enes, J. Am. Chem. Soc. 2006, 128, 10020-10021. John E. Baldwin and Jean-Marie Fedé, Thermal Isomerizations of 2-d-1-(E)-Propenylcyclobutanes to 4-d-3-Methylcyclohexenes, J. Am. Chem. Soc. 2006, 128, 5608-5609. » View all Publications