Studying the 1,5-hydrogen shift in 1,3-pentadiene and 1,7-hydrogen shift in 1,3,5-heptatriene via valency interaction formulas

CHED 1034

Bess Vlaisavljevich, vlai0001@morris.umn.edu, Ching-Wen Hsu, hsuxx080@morris.umn.edu, and Joseph D. Alia, aliaj@mrs.umn.edu. Department of Chemistry, University of Minnesota Morris, 600 East 4th Street, Morris, MN 56267
Hydrogen shift reactions for the 1,5 hydrogen shift and the 1,7 hydrogen shift in 1,3-pentadiene and 1,3,5-heptatriene respectively were examined using the valency interaction formula (VIF) method in conjunction with DFT B3LYP 6-311G++d,p and HF 6-311G++d,p. Results consistent with the frontier orbital method of Kenichi Fukui and the Woodward-Hoffman rules were found. VIF is a pictorial form of MO theory derived from quantum mechanics and is easily verifiable with known molecular properties. VIF pictures represent effective one-electron density or Hamiltonian operators and for this reason can be used to derive qualitative properties of molecules. The VIF approach gives results consistent with all of the other methods used. The 1,5 H-shift transition structure is suprafacial, while the 1,7 H-shift transition structure was determined to be antarafacial. The energy differences between the reactants, transition structure, and products were determined computationally and agreed with VIF and the other qualitative methods.