Managing student needs for effective learning in a large-enrollment, introductory organic chemistry course can be a challenging task. Because instructor time is at a premium, it is imperative to find resources that engage the students in active learning and provide them with feedback about their understanding of course content. Appropriately designed online homework systems can provide this level of engagement. Here we describe our experience with using the Sapling Learning online homework system in an organic chemistry course for prepharmacy majors. Based on the literature describing the effectiveness of online homework in general chemistry and other courses, we hypothesized that student engagement in the online homework would be associated with students’ performance in the course, but that studying with the textbook problems would provide a greater benefit because the material was more sophisticated. We found that engagement in using the system was positively correlated with course grade, and that student perceptions of the system were overwhelmingly positive. Surprisingly, we also found that spending more time studying with the problems in the textbook was not associated with significantly better performance than using the online homework system alone. We speculate that this is because the immediate feedback given by the online system more effectively reinforces the topics. Furthermore, we found that despite the perceived utility of the system and its relationship to final course grades, students still seemed to require an extra-credit incentive to incorporate the use of the system into their study habits. This case study suggests that learning reinforcement through real-time feedback and extra credit (or other points-based) incentives to motivate participation are important components of achieving student benefits from an online homework system.

The reagent [7,7-bis(trifluoroacetoxy)iodo]benzene, PIFA, brings about the facile oxidative rearrangement of aliphatic amides to amines in mildly acidic (pH 1-3) mixed aqueous-organic solvents. Aromatic amines are further oxidized by the reagent and therefore cannot be prepared by this method. The rearrangement, which is in effect an "acidic Hofmann rearrangement", occurs with complete retention of configuration in the migrating group,

This paper addresses the complexity of pH dependent reaction rates in a systemic fashion. By doing so, the author demonstrates that this complexity can be boiled down to simple principles.

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