All that Glitters is Gold: Modeling Catalysis of Hydride Shifts

Functionalizing C(sp3)-H bonds through gold-catalysis has been the focus of several recent studies, for the development of more efficient processes will have numerous applications in the fields of organic and biochemical... [ view full abstract ]

Functionalizing C(sp3)-H bonds through gold-catalysis has been the focus of several recent studies, for the development of more efficient processes will have numerous applications in the fields of organic and biochemical synthesis. Dr. Fabien Gagosz has contributed significantly to this field and proposes a number of mechanisms for his syntheses, many of which proceed through a proposed [1,5] or [1,6] hydride shift. This project aims to develop a quantum computational model for four of these hydride shift mechanisms, and compare their structural barriers to reactivity. Reaction pathways for each proposed mechanism are computed by the Gaussian software, using DFT methods with the B3LYP functional and 6-31G(D)/LANL2DZ(Au) split basis set. Energetics of the reaction are calculated from transition state structures and from endpoints of intrinsic reaction coordinate calculations using the conformational analysis software Spartan. Results have shown discrepancies with proposed pathways; in one reaction, an additional nitrogen loss step is observed, and in another, the addition of electron withdrawing substituents results in a concerted mechanism, contrary to Gagosz' hypothesized stepwise process. Further work will focus on new catalysts, varied substituent groups, and solvent effects.