This thesis is about how Fe catalysts can be degraded using photocatalysis and how Fe catalysts can degrade small molecules in conjunction with light. The goal of this paper is to look further into more sustainable methods of organic chemistry. Many current organic chemistry practices involve the use of precious metals. Iron is a more sustainable catalyst because it is abundant and inexpensive which is important for preserving the earth and making the organic chemistry more accessible. Along the same lines, light is a renewable energy source and has demonstrated its ability to aid in reactions. Overall, the goal of this paper is to explore the more sustainable alternatives to harsh and toxic organic chemistry practices through the use of Iron and light.

The development of novel aqueous cross-coupling strategies has emerged as a rapidly expanding area of research within organic synthesis. However, many of these cross-coupling reactions require the pre-formation of an organohalide substrate, which often involves toxic halogenating reagents and harsh reaction conditions. This work details the development of a tandem halogenation/cross-coupling procedure in which an electron-rich arene or heteroarene is brominated through an enzymatic halogenation reaction catalyzed by a vanadium dependent haloperoxidase (VHPO) and then used without workup in a subsequent aqueous Suzuki cross-coupling reaction. This sequential process allows the arylated product to be accessed in a single pot from the unfunctionalized substrate via the brominated intermediate. Optimization of the enzymatic halogenation step was performed for three different substrates, resulting in the discovery of conditions for the bromination of 2,3-dihydrobenzofuran, chromane, and anisole in high yield (>95%). The scope of the reaction was then investigated for a range of electron-rich arene and heteroarene substrates. Next, Suzuki cross-coupling conditions were developed in a reaction mixture of pH 5 citrate buffer and acetonitrile and applied to the arylation of 2,3-dihydrobenzofuran utilizing an array of arylboronic acid coupling partners. Finally, the two procedures were combined to perform a tandem enzymatic halogenation/aqueous Suzuki cross-coupling of 2,3-dihydrobenzofuran to give the arylated product in 74% yield.

The trifluoromethyl group is an essential chemical motif in pharmaceutical and agrochemical industries. The trifluoromethyl group has similar steric bulk to a methyl group, but exhibits strongly electron withdrawing properties. As a result, a trifluoromethyl group can provide a molecule with enhanced lipophilicity, bioavailability, and metabolic stability, which makes it a commonly used tool to tune activity of agrochemicals and pharmaceutical candidates. There are many methods to generate a new trifluoromethyl moiety, but many of these methods rely on stoichiometric metal reagents or harsh reaction conditions. One strategy to install the trifluoromethyl group under benign conditions is with photoredox catalysis. In the field of photocatalysis, iron has emerged as an alternative for precious metals due to its low cost, earth-abundance, and environmentally benign nature. Methods of trifluoromethylation utilizing iron catalysis do exist, but they often rely on expensive CF3 precursors such as Togni’s Reagent and trifluoromethyl iodide. This thesis demonstrates a method using iron photocatalysis for decarboxylative trifluoromethylation of alkenes using trifluoroacetic acid. We have successfully enabled trifluoromethylation of select methoxy-substituted benzene derivatives as well as a number of alkenes, including those bearing sulfone and ketone groups.