Discovery and Evaluation of Catalytic Allylation and Amination Reactions

Abstract

Presented herein is the development and evaluation of several palladium-catalyzed allylic alkylation reactions and a method for visible light-mediated radical decarboxylative amination. These atom economical, environmentally friendly reactions generate molecular complexity via reactive intermediates formed in situ via the loss of carbon dioxide. In Chapter One, an overview of the state-of-the-art regarding the combination of transition metal and photocatalysis, is presented. In Chapter Two, efforts to combine palladium and photoredox catalysis to effect the radical decarboxylative allylation (DcA) of amino acids and esters, are detailed. This reaction extends the scope of the traditional DcA reaction to carboxylic acids that do not typically undergo two electron decarboxylation and produces CO2 as the only stoichiometric byproduct. The substrate scope was evaluated and several salient mechanistic observations were made based on a variety of experiments. Alkyl and phenylacetic carboxylic acids were also used as traceless activating groups for site-selective radical aminodecarboxylation reactions in Chapter Three. This direct functional group interconversion of non-activated carboxylic acids was achieved using mild reaction conditions and tolerated a variety of desirable functionalities. In Chapter Four, typically unreactive allylic alcohols were activated towards palladium-catalyzed Tsuji–Trost reactions by the addition of carbon dioxide. Oxidative addition toward palladium occurred after reversible carbonate formation to provide an electrophilic palladium-π-allyl species and a potent base for the activation of a variety of pronucleophiles in situ. Ultimately, this method allowed for the topologically obvious C–C bond formation while forming water and carbon dioxide as waste.