One thing I was really looking forward to when switching to Karty’s mechanistically organized text was how reactions involving alkenes would be addressed. I expected to see the reactions simply grouped by mechanism; for example, the electrophilic addition reaction mechanisms would be grouped together, as would the pericyclic reaction mechanisms and so on. Instead, I … Continue reading Life is Hard Enough. Why Teach Alkenes By Function?
Like many other instructors, I do the majority of spectroscopy instruction in my laboratory. It seems natural to integrate spectroscopy problems into lab exercises, and to use the molecules we make as the platform for understanding how to analyze them. Most organic texts I have seen introduce spectroscopy towards the end of the first semester … Continue reading Spectroscopy: Seeing (and Using) the Big Picture
There were two places in Joel’s text that surprised me: where 1,2 versus 1,4 addition to a conjugated diene appeared—Chapter 11—and where direct versus conjugate nucleophilic addition to polar pi bonds appeared—Chapter 17. Both of these chapters introduce basic concepts and then expand all the way to complex applications, much further than a functional-group organized … Continue reading When to Introduce Conjugate Addition: Sometimes More is More
For years I told my students they shouldn’t merely memorize a list of reactions. But what were my actions really telling them? In the last textbook I used, the alkene chapter began with nomenclature, then covered Markovnikov addition of H-X and water, halogenation and halohydrin formation, and ended with hydroboration/oxidation. The next chapter that covered … Continue reading How the Ten Elementary Steps Unified My Course
Since this is the second year I am using Joel’s text, I was sure that I would be comfortable with the syllabus and schedule I set. But I again became nervous as I approached Chapter 11, “Electrophilic Addition to Nonpolar Pi Bonds.” Years of slogging through additions to alkenes and alkynes, working example after example … Continue reading No More Fearing Alkenes and Alkynes
At Butler, we have four learning goals for our students in organic chemistry: to learn the language, drawing style, and three-dimensional structure of organic molecules; to know and apply organic reactions; to demonstrate understanding of reaction mechanisms; and to integrate this knowledge through synthesis. Of these learning objectives, the most difficult for students to embrace … Continue reading The Right Time for Synthesis?
I have always approached my organic sequence as a mechanism-driven course. Every reaction that we discussed in class started with a mechanism to show how it wasn’t really anything new, but an extension of the types of behaviors we had learned to describe and anticipate. I avoided texts that listed reaction after reaction as completely … Continue reading Memorization Not a Choice: Mechanisms Matter
Of all the chapters in Joel’s mechanistically organized textbook, my favorite is Chapter 6: The Proton Transfer Reaction. Acid-base chemistry might seem like an odd topic to pick in an organic chemistry textbook. It seems almost…inorganic, a throwback to general chemistry of sorts. So why do I like it so much? It accomplishes two vitally important … Continue reading Proton Transfer: Well Begun is Half Done
At the end of the semester the students are typically burned out, busy with all of their final assignments, and in general do not perform as well on the last unit exam compared to the other three units. At Old Dominion University we teach addition to alkenes and alkynes in the last unit, a very … Continue reading Surprising Scores in Unit 4
If writing mechanisms is like giving good directions, then each elementary step is similar to saying “turn left at the stop sign.” You might have to turn right many times during one trip just as you might need multiple acid-base steps during one mechanistic pathway. Joel’s “Most Common Elementary Steps” chapter lays out each possible … Continue reading Chapter 7: Elementary Steps but Giant Conceptual Leaps