Carbon-carbon sigma bond activation: functionalizing C-C and C-CN Bonds via carboacylation and cyanoamidation

Abstract

Chapter One. The content of this chapter broadly describes the growing area of carbon¬-carbon (C-C) sigma bond activation. The barriers to bond activation and the strategies employed to overcome these barriers will be summarized. Examples of stoichiometric and catalytic reactions utilizing strained systems and other thermodynamic driving forces are presented in addition to kinetic strategies enforced through cyclometalation.Chapter Two. The focus of the second chapter is on my discoveries in quinoline-directed C-C bond activation. A series of catalytic intramolecular carboacylation reactions with both alkenes and alkynes will be discussed. The mechanism(s) of such transformations were elucidated by researchers at Hope College and will be presented. The intermolecular carboacylation with norbornenes discovered by other Douglas group members will be acknowledged, and preliminary investigations into the idea of migratory insertion (or sigma-bond metathesis) across cyclopropane will be provided.Chapter Three. The third chapter of this thesis describes my efforts to uncover a synthetically viable directing group for C-C bond activation. Directing groups that are anticipated to be removable and reusable, such as quinoline esters, pyridyl esters, and azaindoles, will be described. Efforts to promote C-C activation with versatile triazene directing groups will be discussed. The strategy of metal-organic cooperative catalysis (MOCC) was explored with guanidines and 2-amino pyrimidine diol derivatives, and the concept of Lewis acid or hydrogen-bond-mediated directing groups will be proposed. Chapter Four. Chapter four provides a selected review of carbon-nitrile (C-CN) bond activation. Cleavage of alkyl, allyl, alkenyl, aryl, acyl, and carbamoyl C-CN bonds that undergo subsequent functionalization will be reported. Intramolecular variations of such reactions are highlighted in complex molecule syntheses.Chapter Five. The final chapter will explain my efforts in developing enantio- and diastereoselective routes to 3,3-disubstituted lactams via C-CN bond activation (cyanoamidation). β-, λ-, and δ-lactams are shown to be effectively prepared through this methodology, and attempts to access ε-lactams will be discussed.