How to Learn Organic Chemistry

I've put together a string of questions and answers in several email exchanges. You might want to skim over ...
The following is a series of emails exchanged with a student about learning organic chemistry.

From:
AA
Date: October 21, 2007 1:27:09 PM EDT
Subject: AGOCM - Purchase Inquiry (10/21/07)

21 October 2007

Could you sell a hard-copy of A Guide to Organic Chemistry Mechanisms, if purchased with a personal check or money order?

From: pw@curvedarrowpress.com
Date: October 21, 2007 2:37:05 PM EDT

Certainly, just send a $35 money order to …
and I'll answer any questions you might have. What text are you using?


From: AA
Date: October 21, 2007 3:28:23 PM EDT

Ege, 6th ed.  (http://college.hmco.com/chemistry/organic/ege/organic_chem/5e/instructors/)

Actually, the class had the option of using the book we used for orgChem I or getting the newly adopted bruice, 5th ed.

I am having some difficulty with reaction mechanisms or, more specifically, combining multiple mechanisms to reach final products.  I'd like to think that the professor is simply using more examples and/or test bank material from the bruice book, as I am not faring as well as I would like on his quizzes.  I would just like more exposure to the basic concepts involved in the mechanisms we are studying this semester.

From: pw@curvedarrowpress.com
Date: October 21, 2007 3:51:09 PM EDT

I had used an early version of Ege, but we too switched to Bruice. A Guide to Organic Chemistry Mechanisms was roughly formed around Bruice. 

My students did very well with the mechanisms from my book. When I look at the struggles students have, it is the struggle to get students to attempt to learn mechanisms (and this was also the struggle in my teaching). While this would probably be far from your instructors teaching philosophy, I wrote supplemental problems that I also used in my quizzes. I slowly realized that if I wanted students to know mechanisms, I should give problems that only asked for mechanisms. As a result, I wrote problems that gave the starting material and product and asked students to supply the mechanisms. I used the same mechanisms that were in my book and in Bruice. Slowly, I began to see mechanistic thinking on quizzes and exams. As a result, my class average more than doubled in the time that I changed to Bruice and I had introduced my book into the class. 

If you are using Bruice in your class, I can tell you which problems from A Guide to Organic Chemistry Mechanisms will match the chapters. I don't know that I can do that with Ege.

PW
 
From: AA
Date: October 21, 2007 4:36:20 PM EDT

hello, again.  (and thank, btw, for giving such attention to my inquiries on a Sunday).

while I plan to master all mechanisms necessary to understand the orgChem reactions we are studying, what I currently need help with are chapters 16-18 in bruice, 5th ed. 

I have a quiz in orgChem II on wednesday.


From: pw@curvedarrowpress.com
Date: October 23, 2007 5:29:44 PM EDT
Subject: Progress?

Are you able to learn the reactions or do you have questions? As you work on it. Make absolutely certain that your curved arrows are 100% correct. There cannot be any errors at that stage as it contains the logic of a reaction. The problems are written correctly. You just need to follow it.

I don't know how much you know, but past experience tells me you are or may be learning the reactions for the first time. You probably pattern matched to products before, and now the problems are getting a lot more difficult and that doesn't work. This seems simple to me, but if a chapter is on additions to a carbonyl group, that is the very first step in all of the reactions. I am always surprised when I see some other reaction being written. That is one of the things I liked about Bruice. For each chapter, you should have some idea about the reactions.

The more you do, the easier it gets!


From: AA
Date: October 23, 2007 9:33:58 PM EDT

I am learning these reactions for the first time.  you're correct, in that I have previously worked on (looked for) patterns. 

I am using your work (A Guide to Organic Chemistry Mechanisms), when I can switch gears back to orgII.  so far, I have copied the reactions a couple times a piece, hoping this "exposure" will at least provide for a "2nd nature" approach very soon.  in fact, my next orgII test is monday.  so I will be working these reactions over and over starting tomorrow afternoon.  I trust it will become easier.

thank you, again, very much.  I may email you with a few questions, if that's alright.

From: AA
Date: October 23, 2007 9:38:20 PM EDT

**quick question:  would a list of reagents going and list corresponding "attacks"/"mini-reactions" be a futile exercise?  or would this lend itself to your methods?

From:
pw@curvedarrowpress.com
Date: October 24, 2007 9:29:45 AM EDT

I really don't know the answer to that question. Early in my teaching career, I had planned to prepare lists like that. Paula Bruice has such a list in her book, but I can't say whether it is a valued exercise. 

If you were to ask which effort would bring a greater likelihood of success, knowing whether a given reagent will attack or to memorize reactants and products versus knowing how a reaction takes place, I'd argue knowing how a reaction takes place is more valuable. If you were to substitute another reagent in place of the one you memorized, I don't know if you would know what the product would be because the problem has changed. If you know how the reaction takes place, then you will have some mechanistic expectation of the new reagent. If it must add to a carbonyl group, does it have electrons that can be donated? If the electrons are between a carbon and a metal, you can use a generalization that the metal never holds the electrons. If you noted my Chapter 1 discussion about atoms, you would know that carbon does not hold its electrons very closely. Therefore they are available for reaction. 

In class, I began to expect that students who used flash cards would score lower than those that just learned mechanisms. Flash cards may be fast and easy, but they didn't follow my thinking of how our brains learn the language of organic chemistry. Mechanisms contain a chemical logic. The Gettysburg Address contains a linguistic logic. Without that logic, it is very difficult to memorize the Gettysburg Address. You might be able to memorize the first line and the last line in Swahili, but if someone asked you to explain what either line meant in Swahili, I'd say you would be out of luck. Learning a language is learning a linguistic logic. A connection between words and ideas. It is that connection that lets us communicate. So it is with chemistry. It is just like learning a language. 

What I don't know about your class is whether your instructor waters down mechanisms and reactions. Does he avoid either? Does he focus on nomenclature or ??? (fill in topic)? Some instructors choose a book to avoid mechanisms. In that case my book would not be as useful. However, since your instructor is using Bruice, I doubt that is the case. (By the way, since your instructor changed, I'd try to pick up Bruice, borrowed, used, or even last edition. It doesn't change that much.) 


From: AA
Date: October 24, 2007 3:54:27 PM EDT
Subject: RE: Progress?

gotcha. 

my prof has been laying out all the mechanisms, but very quickly.  he doesn't really go into the steps involved.  he just shows the mechanism, says "this is such and such mechanism", then moves to the next.  there are plenty in the carbonyl-specific section.

... now focusing on how a reaction takes place .... :)


From: pw@curvedarrowpress.com
Date: October 25, 2007 5:55:02 PM EDT

Sometimes I used slides from Part A, and added the curved arrows. I did that just so I could discuss the reactions. Since students had the reactions also, they could fill them in. That probably wasn't as good as just walking around the class and asking the students to fill them in. If students made common errors, then I would make announcements or think about how I needed to change my book. 

This summer, I had some really good students. I don't think Part A would cut it. These guys could do Part B or some could do Part C in class. Why should I lecture to them?


From: AA
Date: October 25, 2007 9:30:52 PM EDT

I am amazed at how much I can do already with the help of your work.  just yesterday morning, I couldn't predict products or suggest reactants for reactions involving acyl halides, anhydrides and esters.  now, it seems sort of silly that I had such a hard time with these at all.  during breaks at work and over lunch, I have just been writing them out .... doing practice problems ... reviewing mistakes, which are not as frequent now ... writing them out again ... practice problems, etc. 

I am moving into amides and nitriles tonight.  tomorrow, on to acid/base catalyzed hydrolysis ... this is becoming fun ... almost like a puzzle.  I can tell where things must "fit" once I know what they are reacting with or what they will become.  I can see where trying to memorize reactants wouldn't really serve my understanding too well.  I may forget a step/reactant working this way.

I really can't thank you enough for helping me. 


From: pw@curvedarrowpress.com
Date: October 25, 2007 10:20:57 PM EDT
Subject: Re: Progress?

Thank you for the endorsement. Although I didn't always hear such comments, but I heard them pretty frequently. I would not have ventured into trying to market this book unless I had students telling me this. When I left the university, many student in my class had sent me their endorsements. What I did not think of was that when I deleted all of my email messages upon leaving the university was that I thought I had them safely stored on my home computer. Well, when I opened my mail program, it saw the messages were deleted and it wiped them off my home computer as well. Ouch. That killed a bunch of nice endorsements. 

If you like the book, tell your friends and tell your professor.


From: AA
Date: November 1, 2007 4:11:28 PM EDT
Subject: A Guide to Organic Chemistry Mechanisms - Progress (11/1/07)

I just wanted to let you know ... I had an exam in OrgChemII on Monday of this week.  I got an 89% (class avg was about 49%).  I am sure the improved performance I enjoyed was due primarily to your text AND heeding your encouragement to actually write the mechanisms out instead of trying to memorize the reactants, products, etc.  I had heard that this was necessary before.  This argument, coming from you, was apparently what I needed to get in gear.

So again, I must say thank you.


From: pw@curvedarrowpress.com
Date: November 2, 2007 5:37:29 PM EDT

I am pleased to learn of your good results. Students able to get 89% are the kind of students I want to attract. So you went into the exam with knowing how reactions take place and voila, you could predict the product with that knowledge. This seems too simple, doesn't it? 

Tell your friends. 

From: AA
Date: December 19, 2007 2:04:07 PM EST

Subject: A Guide to Organic Chemistry Mechanisms - Victory (12/19/07)

I hope this message finds you well.  I wanted to thank you again for TLOC.  I believe the practice I had in using your book really helped with my overall understanding of organic chemistry mechanisms.

My organic chemistry II final was last week.  I got an A in the class.


From: pw@curvedarrowpress.com
Date: December 20, 2007 11:27:45 AM EST
Subject: Re: A Guide to Organic Chemistry Mechanisms - Victory (12/19/07)

I am pleased to learn of your results, and I am happy that you persevered. It seems obvious to me that you should be able to solve at least one example of a problem to solve another similar problem, but it is difficult to get students to follow that advice, especially in my absence. What you did is what I did in college and your results are my results. For this reason, I love getting good students to use my book, they usually do really well. You simply validate what I saw in my classes. I have less knowledge of how students do in other classes, so I am pleased to learn of your results. 

Best,
PW

PS, thanks for giving me all of the great quotes, see
www.curvedarrowpress.com for your others. This too will make it there (eventually).