Tag: Alkenes

Spectroscopy: Seeing (and Using) the Big Picture

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

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When to Introduce Conjugate Addition: Sometimes More is More

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

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How the Ten Elementary Steps Unified My Course

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

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No More Fearing Alkenes and Alkynes

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

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The Right Time for Synthesis?

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

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Memorization Not a Choice: Mechanisms Matter

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

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Proton Transfer: Well Begun is Half Done

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

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Surprising Scores in Unit 4

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

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Chapter 7: Elementary Steps but Giant Conceptual Leaps

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

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Solving the IR Puzzle

My three year old son recently has shown interest in solving puzzles. He dumps the pieces on the floor and randomly clicks them together until he finds a match. This is often the same approach that students take to problem solving in organic chemistry. To help my students work more systematically, I introduce IR early

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