Unprecedented Azine Formation via Proton Tautomerism of Isoquinolyl-1-hydrazones
Open Access
Author:
Lauro, Samantha Lee
Area of Honors:
Letters, Arts, and Sciences (Abington)
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Kevin Charles Cannon, Thesis Supervisor Ann Marie Schmiedekamp, Thesis Honors Advisor
Keywords:
Hydrazone Azine Tautomerism Isomers Density Functional Gas Phase Calculations
Abstract:
Previously reported structures of isoquinolyl-1-hydrazones were subjected to electronic structure calculations using density functional theory (DFT). For six targeted compounds, calculations were applied to multiple conformations for both azine and hydrazone tautomers in order to determine the relative energies of the possible conformations. Then calculations were performed using the hybrid functional B3LYP and a 6-31G**++ basis set using the program Jaguar. The lowest gas phase Gibbs free energy conformation was a function of substitution. In some instances, an azine tautomer was the lowest energy conformation, and in others it was a hydrazone. Compounds which showed a significant calculated preference for either the azine or hydrazone tautomer were synthesized and characterized by x-ray crystallography. All compounds synthesized thus far demonstrate a preference for the azine tautomer, showing mixed agreement with the calculated preference.