Cyclic azomethine imines possessing a β-aminocarbonyl motif are accessed from simple alkene and hydrazone starting materials. A thermal, concerted alkene aminocarbonylation pathway involving an imino-isocyanate intermediate is proposed and supported by DFT calculations. A notable feature of the process is the steric shielding present in the dipoles formed, which allows for facile purification of the products by chromatography or crystallization. In addition, a fluorenone-derived reagent is reported, which provides reactivity with several alkene classes and allows for mild derivatization of the dipoles into β-aminoamides, β-aminoesters, and β-amino acids.

Creating and using models are essential skills in chemistry. Novices and experts alike rely on conceptual models to build their own personal mental models for predicting and explaining molecular processes. There is evidence that chemistry students lack rich mental models of the molecular level; their mental models of reaction mechanisms have often been described as static and not process-oriented. Our goal in this study was to characterize the various mental models students may have when learning a new reaction mechanism and to explore how they use them in different situations. We explored the characteristics of first year organic chemistry students’ (N = 7) mental models of epoxide-opening reaction mechanisms by qualitative analysis of transcripts and written answers following an audio-recorded interview discussion. We discovered that individual learners relied on a combination of both static (with a focus on symbolism and patterns) and dynamic (reactivity as process or as particles in motion) working mental models, and that different working mental models were used depending on the task. Static working mental models were typically used to reason generally about the reaction mechanism and products that the participants provided. Dynamic working mental models were commonly used when participants were prompted to describe how they pictured the reaction happening, and in attempting to describe the structure of a transition state. Implications for research, teaching, and learning from these findings are described herein.

In chemistry, novices and experts use mental models to simulate and reason about sub-microscopic processes. Animations are thus important tools for learning in chemistry to convey reaction dynamics and molecular motion. While there are many animations available and studies showing the benefit of learning from animations, there are also limitations to their design and effectiveness. Moreover, there are few experimental studies into learning chemistry from animations, especially organic reaction mechanisms. We conducted a mixed-methods study into how students learn and develop mental models of a reaction mechanism from animations. The study (N = 45) used a pre-/post-test experimental design and counterbalanced static and animated computerized learning activities (15 min each), plus short think-aloud interviews for some participants (n = 20). We developed the tests and learning activities in a pilot study; these contained versions of an epoxide opening reaction mechanism either as static (using the electron-pushing formalism) or animated representations. Participants’ test accuracy, response times, and self-reported confidence were analyzed quantitatively (α = 0.05) and we found that, while participants showed a learning effect, there were no significant differences between the static and animated learning conditions. Participants’ spatial abilities were correlated to their test accuracy and influenced their learning gains for both conditions. Qualitative framework analysis of think-aloud interviews revealed changes in participants’ reasoning about the test questions, moving toward using rule- and case-based reasoning over model-based reasoning. This analysis also revealed that dynamic and transitional features were incorporated into participants’ working mental models of the reaction mechanism after learning from animations. The divergence of participants’ mental models for reasoning and visualization could suggest a gap in their mental model consolidation.

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Research poster sessions are an excellent example of how scientists rely not only on technical skills but also on interpersonal interactions, communication, and other behaviors learned from participating in social environments. This process of learning is described by social cognitive theory, and particularly its aspects of self-regulation, self-reflection, and self-efficacy. Social learning and cognitive apprenticeship models were used to design a virtual poster session for upper-year students doing research thesis projects. Interactions (reactions, comments, and calls) among students, faculty, and graduate students were examined through a social network analysis of the session, and the emerging communication patterns were related to students' abilities to observe, model, and articulate behaviors in the virtual setting. A survey of student experiences provided insight into the session's outcomes and students' self-efficacy beliefs after the session. The poster session succeeded at creating a virtual space for social learning, reflecting on social norms in science, and for asking questions about research through a cognitive apprenticeship model.