Palladium-Catalyzed Cross-Coupling of N-Sulfonylaziridines with Boronic Acids and Synthetic Approaches to Organic Polymer-Supported One-Dimensional Metal Wires

Abstract

The development of new reaction methodologies has been the gateway through which chemists have come to understand the world. In pursuit of making something better, faster, or completely novel, the synthetic community has happened upon observations that have had indisputable and far-reaching impact on the way society functions. New drugs are made, materials obtained, and physical and biological interactions revealed through synthesis. Herein, two disparate projects falling under the synthetic umbrella, each with a different end goal, are described. In Chapter 1, a new method for forming Csp3-Csp2 bonds is reported. The products of this reaction are β-phenethylamines, a structural motif that is present in a number of biotransmitters and pharmaceuticals. The reaction uses N-sulfonylaziridines as electrophilic coupling partners in a Pd-catalyzed cross-coupling with arylboronic acids. Productive Csp3-C bond formation is often hampered by β-hydride elimination, an undesirable side reaction presently addressed by bimodal coordination of the aziridine to Pd and use of a bulky phosphine ligand. The reaction is high yielding, tolerant of a breadth of functionality, and completely regio- and diastereoselective. Chapter 2 of this work details efforts to develop a synthetic method for the realization of new organic photovoltaic materials. These materials are composed primarily of polymeric organic ligands capable of coordinating transition metal ions such that the ions are organized into one-dimensional metal wires. These 1-D metal wires could function to amplify the polarizability of the organic material and serve as charge-carrying conduits, thereby augmenting solar conversion efficiencies beyond current OPV thresholds. Characterization of these products was complicated by their limited solubilities in organic solvents. Preliminary UV/Vis data indicate red-shifted spectral absorbance profiles for some of the metalated materials; however, absorbance intensities in the visible region are poor, necessitating improvement if these materials are to be used for the originally intended purpose.