This dissertation discusses the development of aminocarbonylation reactions with ammonia and either an aryl or alkyl halide, coupling reactions between hydrazine and aryl halides, and studies of the mechanisms of these two classes of reactions. The synthesis and reactivity of arylnickel(II) amido complexes is also described.

Chapter 1 presents an overview of Pd and Ni-catalyzed C-N coupling reactions. This chapter includes a description of the development of these reactions and a synopsis of the mechanistic studies that have been conducted for each C-N coupling reaction. This chapter also describes the challenges faced when developing systems to catalyze C-N coupling reactions with hydrazine and the mechanistic questions related to that transformation, which have gone unexplored. Pd-catalyzed carbonylative cross-coupling reactions are also discussed, and the mechanism of key elementary steps in these reactions are outlined, which were recently elucidated by work in our group.

Chapter 2 presents a study of the mechanism of a Pd-catalyzed aminocarbonylation reaction between chloroarenes and ammonia. The mechanism of this reaction was proposed based on kinetic, spectroscopic, and computational data. Additionally, 13C KIE measurements and a Hammett analysis were performed to obtain further data on the mechanism of oxidative addition of a chloroarene to a three-coordinate Pd(0) carbonyl complex. A catalyst deactivation pathway, which involved the formation a Pd(I) dimer with bridging carbonyl and hydride ligands, was also elucidated, and the rate-limiting step of the catalytic reaction was shown to be the oxidative addition of chloroarene to Pd(0).

Chapter 3 details efforts to develop and study a Pd-catalyzed aminocarbonylation reaction between aniline and alkyl bromides. Preliminary data obtained for this aminocarbonylation reaction are consistent with oxidative addition of the alkyl halide to a Pd(0) species by a mechanism involving an alkyl radical.

Chapter 4 describes the synthesis and reactivity of a small library of arylnickel(II) amido complexes, which have been crystallographically characterized and are stable at room temperature.

Chapter 5 presents the development and mechanistic study of a Pd-catalyzed C-N coupling reaction between aryl chlorides and hydrazine. Aryl hydrazines can be synthesized in high yield and with catalyst loadings as low as 300 ppm by this protocol. Several examples of aryl hydrazines are provided that are relevant to the synthesis of agrochemicals. The synthesis of an arylpalladium(II) hydrazido species was undertaken and demonstrated to undergo reductive elimination to give aryl hydrazine. Additional mechanistic studies were performed that identified two resting states of the catalyst, an arylpalladium(II) chloride species and an arylpalladium(II) hydroxo complex. The hydroxo compound reacts with hydrazine to give aryl hydrazine, but this palladium complex was demonstrated to be unselective towards mono- versus diarylation of hydrazine.

Learning Objectives: To investigate whether augmenting joint reduction education with 3D printed task trainers will offer a learning benefit when paired with traditional teaching methods using lectures and videos. The application is focused on EM residents with potential expansion to surgical subspecialties.

Introduction: Prior studies and EM training programs have called for the need for innovation in the realm of orthopedic education. When compared to other core skills developed during EM residency, joint reductions are relatively infrequent. The development of 3D printing technology offers an opportunity for the development of task trainers to supplement resident experience. There are no current 3D printed task trainers available for joint reductions. We developed a series of 3D printed joint models with orthopedic curriculum to supplement exposure to dislocation reductions to improve emergency medicine residents’ preparedness, confidence, and competency in joint dislocation reductions. Models were designed to create tension and tactile feedback upon reduction. The supplemental curriculum summarized patient evaluation, anatomy, and techniques.

Curricular Design: We utilized the trainers in simulation sessions with reductions taught using Peyton’s 4 step approach, and competency assessed through Miller’s pyramid educational theory. A likert type survey was administered to assess resident learning, preference in teaching style, and confidence in reduction techniques. Baseline experience data was collected to assess prior clinical experience. Learning retention will be assessed during the follow up skill session. Given the variety of joints designed, we divided sessions to include 1-2 joints at a time. This allowed for more focus on specific joints as well as space repetition across multiple sessions throughout the academic year.

Impact/Effectiveness: The current set of data strongly supports the utilization and integration of 3D models into the education of emergency medicine residents in joint dislocation reductions. The vast majority of resident learners found benefit in the inclusion of 3D printed joint models. Although most learners preferred the 3D printed models compared to traditional teaching methods, we advocate for an integrated teaching model rather than choosing only one teaching technique.