Abstract

From 2003 to 2015, Schӧnecker and Baran proposed a dinuclear Cu/O2 species in their mechanistic proposal for the hydroxylation of sp3 C-H bonds within their systems (proposed based on yields). Inspired from the site selectivity of this methodology and poor analysis of the mechanism, the first project was inspired to re-examine the sp3 C-H bond hydroxylation by Schrӧnecker and Baran and perform an intensive investigation into understanding how Cu/O2 interact which led us to propose a new mechanism based on the evidence collected (i.e., LCuII-hydroperoxide species that undergoes homolytic O-O bond cleavage). From there the scope of the substrates was expanded to studying the reaction by which Cu and O2 oxidize sp2 C-H bonds followed by an extensive mechanistic investigation into the intermediate (LCuII-hydroperoxide species that undergoes heterolytic O-O bond cleavage) as well as expansion of the sp3 substrates. While investigating the sp2 mechanism we discovered a side product formation while optimizing the conditions (conditions: CuII, H2O2, and base). This side product formation was characterized as a 2H-1,3-benzoxazine-derivative. Benzoxazines are used in pharmaceutical and in bioactive molecules and there are a few metal catalyzed reactions. However, the starting materials must be pre-functionalized, and the conditions are quite harsh. After close examination of our conditions, we decided to optimize the reaction conditions and study the mechanism for the intermediate species responsible for this transformation (2-azallyl radical intermediate). From there, projects have been developed on understanding the effects of changing the directing group and studying the reactivity of the new systems.

Degree Date

Spring 5-15-2021

Document Type

Thesis

Degree Name

Ph.D.

Department

Chemistry

Advisor

Isaac Garcia-Bosch

Subject Area

Chemistry

Format

.pdf

Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License

Download

Share

COinS