Dr. William Kelly

EDUCATION

Computational Evaluation of Transition State Barrier Heights for Hydrogen Atom Abstraction by a Chlorine Atom 

Dr. William J. Kelly (Mentor)

Background: Free Radical chlorination is of considerable importance in organic synthesis, industrial reactions and stratospheric chemistry.  It forms the basis for the production of dichloromethane, chloroform and other chlorinated hydrocarbons.  It is the primary channel for loss of atmospheric methane and as a result has a significant impact on atmospheric greenhouse gas models.  Hydrogen abstraction by chlorine is the first step (eq 1) in the propagation of free radical chlorination.  Thus accurate determination of thermodynamic/kinetic parameters for this process is important across several areas of chemistry. Unfortunately the level of experimentally determined data is sparse. 

R-H +  Cl  →  R  +  Cl-H     (1) 

Computation quantum chemistry is a powerful tool for obtaining such data.  High-level computational methods allows determination of thermodynamic parameters with a high degree of accuracy but at present are applicable to very small systems.  Finding a compromise between accuracy and computational cost is important in further advancing the theoretical investigation of these reactions.

Methods: Several new Density Functional Theory (DFT) methods have been developed in the group of D. G. Truhlar that appear to offer the best compromise between accuracy and computational expenses for the evaluation of transition state barrier heights.  We will first employ these methods (M06-2x, M11 and M15) to the evaluation of hydrogen abstraction Energies in several systems in which the barrier heights have been determined experimentally.  After evaluating the accuracy of each method we will then examine a number of important reactions for which the parameters are not known. 

Student Skills: Completion of Physical Chemistry is not necessary for any student engaged in this project. The mentor will provide a mostly non-mathematical introduction to the theory behind computational quantum chemistry. The mentor will train the student in the use and application of the Gaussian 16 suite of computational methods and how to interpret and analyze the results of computations. The student will be introduced to the Linux OS and how to carry out specific command line operations within Linux. At the end of this project, the student will be able to carry out structure determinations and energy calculations on organic molecules and be able to determine transition state structures and energies of reactions.

CONTACT INFORMATION

Email: william.kelly@swosu.edu Office Number: CPP 205-C
Phone Number: 580-774-3202

TEACHING: BASIC COURSES

CHEM 1004L Gen Chem Lab
CHEM 1252 Gen Chem I Lab
CHEM 1352 Gen Chem II Lab

TEACHING: ORGANIC CHEMISTRY

CHEM 3013/3015 Org Chem I
CHEM 3111/3015L Org Chem I Lab
CHEM 4113/4115 Org Chem II
CHEM 4021/4115L Org Chem II Lab
CHEM 4554/L Advanced Organic Spectroscopy/Lab
CHEM 4900 Seminar Attendance CHEM 4901 Senior Seminar

RECENT PUBLICATIONS

Kelly W. “Computational Evaluation of Benzene-Chlorine Atom Complexation”, J.Comp. Chem., 2002, 23(11), 1129-1132.

W.J. Kelly*, E.B. Smith and J.A. Amanfu, “Novel Homoaromatic Metallocenes: The Synthesis, Structure and Properties of (Bicyclo[2.2.1]octa-2,5-dienyl)(pentamethylcyclopentadienyl) ruthenium (II)}. J. Organomet Chem., 238, 113 (1994)

W.J. Kelly* and S.I. Chen, “Carbanions Which Function Both as Electron-Transfer Agents and Hydrogen Atom Donors: A New Electron -Transfer Chain REaction,” J. Org. Chem., 53, 1830 (1988).

W.J. Kelly, G.W. Gribble, and D.J. Keavy, “Unexpected Regio-selective Diels-Alder Cycloaddiction Reactions Between 3-Fluoro-benzyne and 2-Alkylfurans,” Tetrahedron Letters, 29, 6227 (1988).

W.J. Kelly, N. Kornblum, and M.M. Kestner, “Electron Transfer Substitution Reactions of Anions Derived From Malonic Esters, B-keto Esters and B-diketones,” J. Org. Chem., 50, 4720 (1985).

W.J. Kelly and G.W. Gribble, “Through Space Hydrogen-Fluorine and Carbon-Fluorine Spin-spin Coupling in 5-Fluoro-3,3-dimethyl-1,2,3,4-tetrahydrophenanthrene,” Tetrahedron Letters, 3779 (1985).