ChemSemBlog

The Chemistry Seminar that was held on October 1, 2009 involved “Synthesis of N-Alkyl Pyridones: Methodology and Mechanism.” Before talking about the seminar I want to introduce the speaker. The speaker, Carolyn E. Anderson is currently an assistant professor of chemistry at Calvin College in Grand Rapids, Michigan. She received her bachelor’s degree in chemistry from the University of Michigan following the completion of her Ph.D. in organic chemistry at the University of California at Irvine.

Moreover, Anderson has been awarded grants for her research from lots of foundations such as Camille and Henry Dreyfus Foundation, the National Science Foundation Research Corporation for Science Advancement, the American Chemical Society–Petroleum Research Fund and the Arnold and Mabel Beckman Foundation Scholars Program.  Her research provided methods for the synthesis of molecules for pharmacological use.

For our Chemistry Seminar, she introduced her current research developing new synthetic methodologies for preparing N-alkyl pyridones, including amino acid homologues. First of all, N-Alkyl pyridones are interesting motifs due to their prevalence in natural products and their potential to mimic amino acids. Therefore, pharmacological companies are interested in these molecules.

However, they had problems in synthesis, with mixtures of N-and O-Alkylated products generally formed. So, Anderson developed an approach to synthesize pyridones from pyridines.  Specifically, 2-chloropyridines were reacted with benzyl alcohols using heat and base. Through initial microwave screening, her research group formed benzylacetamide. During this process, they also found  better reactions by lowering concentration and temperatures and utilizing conventional heating. Also, their optimization studies proved that both temperature and LiI are needed to produce this synthesis. As always, there are some limitations on this experiment. For example, substitution on the alpha position significantly slowed the rate of migration and reaction.  In conclusion, a new O- and N-Alkyl migration strategy for the preparation of N-benzyl and propargylic pyridones has been developed and an unusual N—Alkenyl pyridone has been observed.

This presentation was fast and there was a lot of information on mechanism which I had a hard time  comprehending. For this presentation, I had some questions on my mind, such as how long they have been working on this research, and what is the microwave screening which I have learned through questioning and answer time. Also, I was impressed with the optimization studies and their approaches regardless of limitations on the experiment.

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The seminar this past Thursday was on the synthesis of N-alkyl pyridones. The speaker was Professor Carolyn Anderson of Calvin College. Her presentation on the organic synthesis of these compounds was understandable and easy to follow especially when compared to the previous week’s presentation by Professor Silas Cook. I think it is safe to say that perhaps after viewing both presentations by Silas Cook and Carolyn Anderson, I can now see the contrasting differences between methodology and total synthesis (at least I hope I am on the right track). It was interesting to learn about both the methodology and mechanism of N-alkyl pyridone synthesis. I was able to see the steps taken in order to answer several questions about the mechanism such as the role of LiI and the other questions on intermediates.

I learned quite a bit from this lecture as she talked about the Hammett correlation equation and other interesting information regarding the practical applications such as its use in pharmacology. I also learned about the steps she took to optimize the reaction for example when she tested different solvents and heat. This reminded me a lot about the independent research projects I did for organic chemistry.

Overall, I would say this presentation was informative and entertaining. Anderson was able to deliver the presentation in a straight forward and easy to understand manner. Her topic was rather interesting and it never really got dull.  For my non-science friends, I would say that this seminar was about learning more about a particular organic chemistry reaction that may prove beneficial in the pharmaceutical industry.

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The speaker was Carolyn Anderson, from Calvin College in Grand Rapids Michigan. She received her bachelor’s degree in Chemistry from the University of Michigan in 1988. She also received a Ph.D. in organic chemistry at the University of California at Irvine in 2003.

Anderson’s research program develops methods for the synthesis of molecules of pharmacological or inherent interest. Currently her research is specifically focused on developing new synthetic methodologies for preparing N-alkyl pyridones, including amino acid homologues.

Anderson was the first woman speaker of this year. She made eye contact with the audience, and in a fast fashion she showed many mechanisms. The topic of this presentation was basically applied research in finding out how alkyl pyridones are prevalent in natural products and they have a potential use as an amino acid mimic.

Some things I learned during this presentation were the importance of N-Alkylated pyridones which is selective ligand for the CB2 receptor. These pyridones are also seen as a potential tissue factor. For microwave studies, these reactions to form N-alkylated pyridines also form a benzylacetamide by-product. In optimization studies, it was found that the reaction worked better at room temperature. The limitations of this experiment were that the substitution on the alpha position significantly slows the rate of migration. A good thing that was learned throughout this experiment was that electron withdrawing groups also increase the reaction rate. In propargylic migration, the migration rate is slower than in the benzyl case.

The overall conclusion for this presentation was that Anderson has developed new oxygen to nitrogen alkyl migration strategy for the preparation of the N-benzyl and N-propargylic pyridones.

Many students asked questions and the speaker answered to the best of her ability, helping the students to better understands the material.

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This week’s seminar was Synthesis of N-Alkyl Pyridones: Methodology and Mechanism.  The speaker was Carolyn E. Anderson who is currently an assistant professor of chemistry at Calvin College in Grand Rapids.  She got her bachelor’s degree in chemistry from the University of Michigan and she completed her Ph.D. in organic chemistry at the University of California at Irvine in 2003 in the laboratories of Larry Overman.  She did her post-doctoral Fellow at Pomona College in Claremont, California.  She was a good speaker and was enthusiastic about the material.

One of the new things I learned in this seminar was that a pyridone ring is similar to the rings in a steroid, making it interesting for pharmaceutical applications.  Another thing I learned was that a Hammett plot correlates the electronic effects of a series of substituents to reaction rate.

The other students seemed to be attentive during the seminar.  There were also a good number of questions at the end, and the speaker answered all of them well.

This seminar did encourage me to look into learning a little more about the topic.  However I don’t think I would be very interested in doing any research on it.

I think the reason that this seminar was interesting was because the speaker was excited about the subject she was presenting.

If I had to describe the seminar in one sentence I would say “the how and why of pyridones.”

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This thursday’s presentation was brought to us by our first female presenter of the year, Dr. Carolyn E. Anderson. Dr. Carolyn is currently an assistant professor of chemistry at Calvin College in Grand Rapids, Michigan. She received her bachelor’s degree in chemistry from the University of Michigan in 1998, and then completed her Ph.D. in organic chemistry at the University of California at Irvine in 2003.

Dr. Anderson leads her team of undergraduate researchers in developing the methodology and mechanism of the synthesis of n-alkyl pyridones.  n-alkyl pyridones are biologically important because they are similar in structure to steroids and also resemble amino acids; thus, they have the potential to be very useful in the pharmaceutical industry. Although the introduction and goals of her research were not very comprehensive, I came to understand that Dr. Anderson is not only interested in utilizing her methodology in a specific molecule, but rather her attention is focused also on determining the mechanism of her method.

Thursday’s seminar was unlike all the others I had seen before. Although I have listened to researchers involved in tedious research such as, total organic synthesis, I had not yet attended a seminar whose main focus was purely methodology.  The length, patients, and tediousness of methodology was far more intense than I had previously thought. Dr. Anderson showed us the results of several experiments they ran, such as, optimization studies and microwave and convectional heating studies; also, for every product obtained, they compiled physical data such as: density, weight, optimum pH levels, etc. In fact, Dr. Anderson had so much information that her quick paced presentation spanned the entire class period.

The result of Dr. Anderson’s research is the development of a new oxygen to N-Alkyl migration strategy for the preparation of N-benzyl and N-propargylic pyridones. She discovered, via cross over experiment, that benzyl migration is an intermolecular phenomenon that involves the splitting and recombination of the O-benzyl molecules. Her team of researchers also proved that the benzylic carbon is positive or partially positively charged by conducting Hammett correlation experiments.

Dr. Anderson’s presentation showed me how  electronic effects can be determined using Hammett’s correlation,  how to interpret positive and negative rho values for a particular reaction and the time and detail that goes into methodology.  If I could go back to lecture I would ask her what she plans to do next, what specific molecules pharmaceutical companies are planning to put this method into use in,  and how/if  they plan to use the new oxygen-iodide bond mechanism  in future experiments.

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Today’s guest speaker for chemistry seminar was Carolyn E. Anderson. She is an assistant professor of chemistry at Calvin College in Grand Rapids, Michigan. She graduated from the University of Michigan with a bachelor’s degree in Chemistry. Also, she earned her doctorate degree in Organic Chemistry at the University of California at Irvine. Currently, Dr. Anderson is doing research on developing new synthetic methods to produce N-alkyl pyridones, as well as amino acid homologues.

Dr. Anderson’s presentation title was “Synthesis of N-Alkyl pyridones: Methodology and Mechanism.” She started the presentation by introducing the class with a new O- to N-alkyl migration strategy for the preparation of N-benzyl and propargylic pyridines. Secondly, she explained about the mechanism of benzyl migration. Lastly, she talked about an unusual product, which she did not expect to produce. Overall, her speaking speed was too fast for me to understand all the things that she explained.

From the presentation, I learned about Hammett Correlation, which correlates electronic effects of a series of substituent to reaction rate. If the p values are negative, the substituent is electron donating group, which increases the reaction rate. However, if the p values are positive, it has an electron withdrawing group.

Throughout the presentation, I was wondering about the theme and objective of  Dr. Anderson’s experiment. Why is she finding a new strategy to synthesize N-Alkyl pyridone? Also, I did not understand the concept of sigma hole. Which factors affect  creating sigma holes?

I found it interesting that N-alkyl pyridones are from nature. Throughout the history, scientists have tried to produce different products to have positive effect on our body system. Those products could heal a disease, or relieve the pain. However, I think that if the products are not nature products, they could cause unwanted side effects on our body. Therefore, the idea of making N-alkyl pyridones from natural products was very intriguing and interesting for me.

Soldiers make various strategies to gain victory. Similarly, scientists make various strategies to get a new product which will lead us to gain victory over various diseases.

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Our first female speaker this semester, Carolyn E. Anderson is an assistant professor of chemistry at Calvin College, in the not too far away Grand Rapids, Michigan. Apparently, ever since she was 10 years old, she knew she wanted to be in the field of science and has stuck to that dream. Her faculty profile describes a well-rounded and accomplished individual.

At Calvin College, her research centers around pyridones (http://en.wikipedia.org/wiki/Pyridone) and attaching other structures to it. They aim to synthesize non natural amino acids and to produce molecules that imitate those made by the body for pharmacological uses. Anderson explained that the key factor taken into account is what the body can make the body can destroy. That is, the imitation molecule is similar enough to be recognized by the body’s receptors, but dissimilar enough so that the body’s natural reaction won’t destroy it too quickly.

Most of the presentation focused on an unusual N-alkenyl pyridone and four mechanistic questions the researchers asked: 1)Is the benzyl migration intermolecular or intramolecular?, 2) When in the reaction is the migration happening, 3) What is the role of the lithium or the iodide in the reaction?, and 4) Is there an intermediate? To find out where the benzyl migration took place, a crossover experiment was done and they found that it was intermolecular migrations. The plotting of a Hammett Correlation showed if there was an intermediate state (was there? I didn’t catch the answer to that). The NMR of the product was misleading, so a crystal form of the substituted benzyloxypyridine, painstakingly obtained, was sent to the crystallographer in another university to be examined. Interestingly the crystallography seemed to indicate that the benzyl migration occurred intramolecularly. They determined that in the crystal form the intermolecular hydrogen bonded ring converted into a intramolecular halogen bond as the intermolecular form is not close enough to form the crystal.

If you read the title of Anderson’s seminar, that is exactly what you get: methodology and mechanism. Unlike most of our previous speakers who skimmed over the actual processes and reaction mechanisms involved in their research, Anderson’s seminar was heavy-handed on them. If the chemistry from Silas Cook’s presentation were over my head, Anderson’s…well, maybe they weren’t so over my head, but the terrible amount of them we had to swim through over the seminar was tiring. It didn’t help that Anderson spoke at a mile-a-minute, sometimes superhumanly fast, although most of the sound barrier breaking speeds were on the molecular names that she’s had to say a million times. To her credit, she didn’t stutter or stumble over those quickly spoken words, an authority on the subject she spoke of, and her demeanor was poised.

To be honest, I was actually a bit late to this seminar, so perhaps I missed out on a crucial piece of the introduction. However, a few questions revealed that I had hardly missed the introduction and that others were lost at sea in what context the material was presented in. Soon afterwards, I believe we let go of our assumptions that we would get as much context as we had in the previous seminars and accepted it as pure chemistry research in all its Wonder. I wonder what microwave heating is (she answered this question, it is a novel heating method, that one day will be more commonly used by students as well as researchers). I wonder what a sacrificial piece is (I presume a molecular structure that was only used for its good leaving group properties). I wonder what a Hammett Correlation is. I wonder if they use a lot of obscure math equations to analyze data. It makes you wonder how anyone could be an expert in science when there is so much to know and new information is always being discovered.

Layman’s Summary of the Seminar: Anderson’s research team developed a new strategy for O- to N-alkyl migrations and during the study of the mechanism of the benzyl migration (WIP) discovered such an unusual molecule that it got put into this presentation.

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This week we enjoyed a presentation from Dr. Carolynn E. Anderson from Calvin College in Grand Rapids, MI. Once again, we listened to the results of research in the field of synthetic organic chemistry. The specific topic was on the synthesis of N-Alkyl Pyridones. Her research was mainly focused on finding a way to specifically bind alkyl groups to the nitrogen of a pyridone as opposed to the oxygen, since both nucleophilic sites were adding in relatively equal proportions. She shared data from NMR spectroscopy and from a crystal structure. The long-term plans for this research was for these N-Alkyl Pyridones to be used as substrates to bind in the place of sterols and some amino acids. Just like in much of organic chemistry, this is a pharmaceutical project.

Dr. Anderson did a fine job up front, and despite appearing to be slightly nervous in the beginning, she began to speak more comfortably as she delved into her material. Being very knowledgeable about the subject matter of her presentation, Dr. Anderson very hastily answered each question she was bombarded with. Since I am not a avid pursuer of organic chemistry, much of this presentation was a learning experience for me. I found it especially interesting when she spoke of the mechanisms proposed and the process by which she and her team eliminated the proposals one by one. My knowledge of NMR data is truly sub-par, but I also learned of how upfield protons can be moved downfield by certain steric interactions. I found the material of this presentation to be slightly less intense than that of Dr. Cook the week before when he talked about a “3D” Diels-Alder reaction, but I was very impressed that all this research had been done by undergraduate students. I give this presentation 9.5/10 for professionalism, 9.5/10 for chemistry content and 8/10 for student engagement.

For the layperson, this seminar talk focused on ways to make chemicals that are of interest in the pharmaceutical world, including some of the techniques to combat troubleshooting in the field of chemistry.

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This week’s speaker was Carolyn Anderson from Calvin College.  Her topic was the methodology and mechanism for synthesizing N-alkyl pyridones.  A pyridone is an aromatic ring with a nitrogen in it, and the nitrogen is bound to a carbonyl carbon.   In O-alkyl pyridones, a benzyl group is attached to the carbonyl oxygen.  In N-alkyl pyridones, the benzyl group is instead attached to the nitrogen.  Pyridones may have additional functional groups attached, such as halides and methyl groups.  Anderson’s goal was to take an O-alkyl pyridone and convert it to an N-alkyl pyridone using a process known as benzyl migration.  Why was she investigating pyridones?  Pyridones closely resemble steroids, so they could have potential use in the pharmaceutical industry.  Pyridones are also similar to amino acids, but the body doesn’t readily recognize and destroy pyridones.  In order for a compound to be of use in medicine, it must be able to survive in the body long enough to function.  When pyridones are made, a mixture of N and O-alkylated products is obtained.  Pharmaceutical companies do not want to take the time to separate the products.

To get the O-alkylated pyridone, Anderson reacted 2-chloropyridine with benzyl alcohol under basic and heat conditions.  Then, she worked on converting the product to an N-alkylated pyridone using lithium and acetonitrile.  Anderson discovered that the mechanism for benzyl migration was intermolecular, meaning that the benzyl group moves from one molecule to another, rather than to a different place on the same molecule.  She also did a Hammett plot, which correlates electronic effects of substituents to reaction rate.  From this plot, it was discovered that electron donating groups such as methyl would increase the reaction rate.  It was best to put a methyl group para to the carbonyl group to minimize any steric hindrance.  Anderson has made great process in figuring out the mechanism of benzyl migration, but the whole mechanism is still unknown.

The presentation was quite interesting for me.  I think Anderson presented the chemistry in a way that can be easily understood.  I also got some insight into what synthetic chemists must do for pharmaceutical companies.  I am interested as to the medicinal applications of N-alkyl pyridones.  If pyridones are similar to steroids, would they have similar functions, such as promoting muscle growth?  I am unsure why Anderson specifically wants to obtain the N-alkyl form and not the O-alkyl form.  I would also like to know if there are any other molecules that have a similar chemistry to pyridones.  For example, could they undergo similar benzyl migrations?  If there were molecules that reacted similarly to pyridones, it might help Anderson figure out the mechanism for benzyl migration.  If I had to sum up this presentation for a layperson, I would say that one form of a potential new medicine was being converted to another form.

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Dr. Carolyn Anderson spoke to us today about the “Synthesis of N-Alkyl Pyridones: Methodology and Mechanism.” She came from Calvin College where she is an assistant professor in the department of chemistry and biochemistry. She works a lot with the undergraduates and they did the research she shared with us. A couple new things that I learned include what pyridones are and that they are of interest to pharmaceutical companies, because they basically look a lot like steroids.

Dr. Anderson went through the synthesis of making the N-alkyl pyridones and the different challenges they faced and still face. The first challenge was making them without having the products being a mixture of N- and O-alkylated. This has resulted in new migration strength for the preparation of N-benzyl. She showed us a lot of the results they have obtained with trying to synthesize them using different methods, such as the use of solvents, variation in temperature and reaction time. Something that was nice was most of the products would not degrade when they were taken off the heat. They would remain stable for weeks.

To be honest I had a hard time with being interested in this talk. Dr. Anderson was very good, but she jumped right into the chemistry of synthesizing her product, and I missed why it was being synthesized. She did say that it interested pharmaceutical companies because it looked like a steroid, but I am not sure what they could do with it. If I would describe this talk to a friend, I am not sure what I would say more than it was about the synthesis of N-Alkyl Pyridones.

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Carolyn E. Anderson is currently an assistant professor of chemistry at Calvin College in Grand Rapids, Michigan.  Aside from teaching and conducting undergraduate research, Anderson also enjoys putt putt golf, cross country skiing, painting, being outdoors, and hanging out with her husband.  If you ever get a chance to speak with Anderson, you will notice that she really loves working with undergraduates.  Most of her research is actually done with undergraduates.  Anderson expresses that she genuinely enjoys working with undergrads because they are very teachable.  She looks at her interaction with undergraduates as a way to help them find their calling.  Anderson herself, started to realize her calling at the primary age of 10 and during high school when she realized that biology was not as interesting as hoped.  Now, Anderson considers herself not only a teacher and a researcher in chemistry, but also as a mentor because of the relationships she has with her students and undergraduate researchers.  According to all that I’ve learned about Anderson, she seems to be very successful and leaving very good impressions on her students as well as the students at Andrews University.  On October 1, 2009, Anderson came to Andrews University to make a presentation on her research in N-Alkyl Pyridones.

First of all, I did not even know what a pyridone was in before Anderson’s presentation, now I do.  A pyridone is an organic compound that is used in peptide synthesis.  It’s a crystalline structure that forms hydrogen bonds related to those found in the base pairing mechanism of amino acids of DNA and RNA.  I thought that this aspect was very interesting and cool, because we recently discussed amino acids and their mechanisms in biochemistry.  Anderson is studying these compounds because they are commonly found in natural products, for example, anagyrine and cystine.  She is researching the methodology of synthesizing N-alkyl pyridones, focusing on developing a new synthetic method for preparing them.  Anderson is also interested in the methodology of amino acid homologues.  Her research can also be used for pharmacology purposes because N-alkyl pyridones have a probability of being used as amino acid imitators.  Thus far, her research has yielded the publication of an article in the Journal of Organic Chemistry (2008), Synthesis of Substituted N-Benzyl Pyridones via an O- to N-Alkyl Migration, which describes her research on the pyridone synthesis.

I also learned about one problem with the synthetic methodology of N-alkyl pyridones:  when the pyridones are treated with a base, they yield same resonance stable anions.  These anions then compete with the desired product.  Basically, the addition of base results in two products, N- and O-alkyl pyridones.  The approach that Anderson is taking to correct this issue is using a commercial pyridine (2-chloro pyridine) and proceeding with an addition, then elimination reaction.  This will result in an O-alkylated pyridine in which its substituent can be migrated from the O- position to an N- position.

The methodology for substrate synthesis worked numerous times however, Anderson is most interested in how the reaction would work under different conditions.  Several experiments showed that lithium iodide (LiH) would be the best solvent to use because it produced the largest yields of desired product.  Optimized conditions resulted in the use of LiH, heat, and approximately eight hours of reaction time to produce the best results.  Anderson also discussed some problems that arose during the experiment, such as the observation that certain substituents did not work because of their positions, such as a methyl group in the alpha position.  Instead it yielded a different heterocyclic compound.  This lead to an investigation into whether the reaction was an intermolecular or intramolecular reaction.  Anderson and her fellow researchers performed various crossover experiments and their investigation resulted in the conclusion that there was an intermolecular reaction happening that was producing this undesired product.  Anderson also touched on electronic effects and how stereoselectivity can be used to reduce benzyl groups.  Further research also yielded in an investigation into a crystal structure that was produced from the reactions.  Anderson and her team performed NMRs on the compound and realized that it was the result of intramolecular halogen bonds due to the iodine and oxygen in the reaction.  A third concept that I learned from Anderson’s lecture is that the mechanism of benzyl migration seems to be intermolecular due to an electrophilic carbon center.

From my perspective, the research was well accepted and Anderson talked with a precise clarity as she lectured on the importance of N-Alkyl pyridines and research in the area.  We as students were able to relate and comprehend the material that Anderson presented and she really did her best to make it interesting and not just another boring synthesis-research seminar.  I greatly appreciate her efforts however, I do not believe that she was the most interesting professor that we have had to present at our chemistry seminars for the semester.  She was rather on the boring end, not because of her research, which I found to be really interesting, but because of her presentation style.  I think that if she spent a little more time explaining the importance of her research then it would have been received a lot better.  The research itself was exceptionally interesting though and I appreciate the knowledge that I have gained on pyridones.  Anderson’s presentation provided a thorough look into the methodology of synthesizing N-alkyl pyridones and how these compounds can be used to better pharmacology.

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Dr. Carolyn Anderson spoke to us today about the “Synthesis of N-Alkyl Pyridones: Methodology and Mechanism.” She traveled to us from Calvin College where she is an assistant professor in the department of chemistry and biochemistry. She works side by side with the undergraduate Chemistry and Biochemistry students that performed the chemical research she shared with us. A couple new things that she brought to our attention was that N-Alkylated pyridones are found in natural products such as, anagyrine, cytisine, and mappicine.    One of the equations she showed us is the following:

This equation is showing us that  a new LiI-promoted O- to N-alkyl migration has been developed for the conversion of O-alkylated 2-hydroxy pyridines, quinolines, and pyrimidines to the corresponding N-alkylated heterocycles in good to excellent yields (57−99%). This method serves as an efficient means for the preparation of N-benzyl pyridones.  Dr. Anderson also told us that when she pulled the reaction off of heat, it thermally quenched.  This allowed her to leave the reaction in a suspended state and return to it at a much later time if needed.  We also learned that when substitution occurs on the alpha position of the benzyl ring, the rate of the reaction is significantly slowed as compared with substitution on the beta position.  Overall, I believe that topic of Dr.Anderson’s research was very interesting, and thoroughly encompassed the area of applied research due to the immense trial and error involved.  However, I feel her presentation style was a little to fast, thus some of the information she shared went over my head.  I believe this could be true for some of my other colleagues that also attended this seminar.

-Danuel Bown

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On Thursday, October 1, 2009, Doctor Carolyn E. Anderson came and spoke to us from Calvin College, which is located in Grand Rapids, Michigan. Her topic of choice for the day was about the synthesis of nitrogen containing carbon rings.  Dr. Anderson graduated from the University of Michigan in 1998 with a BA in science and Chemistry.  After graduating from U of M she quickly left and went to the University of California-Irvine, where she graduated with a Ph.D in Chemistry in 2003 following her graduation she worked two years at Pomona College in Claremont, California before taking her job at Calvin College.

Dr. Anderson specifically works very closely with undergraduate students. This is not practiced very often as it is sometimes harder to work with the students. However, Dr. Anderson feels that these undergraduate students are easier to mold into what is needed rather then a graduate student who thinks that they know everything already.  With her undergraduate students she is currently working on developing methods for the synthesis of molecules of pharmacological interest. She was able to show us a lot of different syntheses that were taking place in her lab and that she had performed and worked on to optimize what she was working toward which is the N-Alkyl Pyridones.  However, I would love to give more information about her discussion but she spoke so fast and moved so quickly through slides that I was unable to collect much information to even jog my memory. I did learn that they discovered new ways to start with an O- alkyl and turn it into an N-alkyl group for the preparation of an N-benzyl ring.  And the other information that I was able to learn was that the benzyl migration from O- to N- is an intermolecular migration.  However, this was the complete extent of my learning from this seminar.  I do not even know where to start asking questions to get more information and better understanding.

Now aside from this problem of not getting much information out of the talk I do have a few positives for the speaker.  Dr. Anderson started a few minutes late due to a lengthy introduction, but she had complete respect for the time restraints of the class period and finished right on time, and was even able to give time for a short Q&A period. I give two thumbs up for this as the last two speakers have not been able to keep it within our time restraints.  She was very knowledgeable of her topic; the few questions that were asked she was able to answer with ease. She spoke fairly loud, but at times I had a very hard time hearing what she had to say.  I give the seminar talk a 5.5 out of 10 overall.  I just had way to hard of a time trying to follow what was going on.

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This week’s seminar lecture was given by Dr. Carolyn E. Anderson from the Calvin College Department of Chemistry in Grand Rapids, Michigan. She gave her talk on the research that her lab has been doing on the synthesis of N-alkyl pyridones and other products. The speaking style of the lecturer was rather fast, and I think she was rushing things a little bit. I do applaud her for staying within the time limit of the class, and she was the first of the guest lecturers to do so.

The talk this week wasn’t too interesting. The subject matter was alright, but I think what turned me off to the lecture was the way in which it was presented. The speaker did not seem to be as into the material as other speakers have been and also the speed in which she spoke was too quick, and those were the reasons this lecture wasn’t interesting to me.

One thing I learned was that unlike most reactions, one of the reactions that they ran didn’t produce any “junk product,” which is a result of there being no discernible intermediate product, yet another anomaly that is a characteristic of this reaction. One thing that I couldn’t understand was why the presence of a methyl group would slow down the reaction. Another thing that I didn’t understand was the fact that the reaction with the base went to both O- and N-alkylates. If I were to explain this lecture to one of my non-science friends, I would tell them that it was about how chemists look at a natural chemical and develop a way to make it inside a lab.

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In this installment of ChemSem, Carolyn Anderson of Calvin College discussed her research regarding the attempted synthesis of N-Alkyl Pyridones. Though the seminar was technical in nature, to simplify matters an N-Alkyl Pyridone essentially involves hydrocarbons attached to nitrogen in a ring containing a double bonded oxygen. Commonly oxygen is the most likely spot of attachment, and this was the difficulty such a synthesis faced.

Dr. Anderson spoke quickly on the topic ranging from the initial phases of research to the many dead ends that accompanied progress in discovering a good way of synthesizing the reagents with the alkyl group correctly attached to the nitrogen. They discovered a problem with most of the substances they tried forming a resonance structure which made the oxygen the most likely binding site. The research is on going.

There were several things I learned in this seminar. To begin with I learned that a Hammett plot is one method of correlating electronic effects of substituents to a reaction rate. Furthermore, they found that though the reaction took place fairly well, it was not an intramolecular mechanism which could be seen by simply substituent testing. Finally, by changing an organic molecule slightly, they discovered they were able to give it a longer life time in the body because it still could function as a common biochemical, but the body was less capable of breaking the material down into waste.

Overall, Dr. Anderson did a good job both with her presentation and in answering follow up questions. The future of this research is sure to hold valuable answers.

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Chemistry Seminar on October 1, 2009 was presented by Carolyn E. Anderson who is an assistant professor at Calvin College in Grand Rapids Michigan. The presentation was largely based on research that has to do with organic chemistry. The presentation was informative and relatively easy to follow although a little fast at times.

During this presentation I was learned that N-Alkylated pyridones are of interest to the pharmaceutical industry because their ring is similar to steroids and they had similar binding to amino acids.  A challenge in this type of research is that when you treat an N-alkyl pyridone with a base the products are a mixture of N-alkylated and O-alkylated products. I also learned some new terminology. I was unaware that “neat” means that a reaction is run without any solvent.  I also learned that a Hammet plot correlates the electronic effects of a series of substituents to the reaction rate.

I thought the microwave screening procedure Anderson described was really interesting. Obviously I have never heard of or used anything this advanced in my chemistry studies. After asking her to clarify, Anderson describes that the device used for microwave screening is a pressurized microwave that can be adjusted to attain an exact temperature for an exact period of time. The sample is moved in to the chamber by the machine itself and taken out again by the same process when the reaction is complete.

When describing this seminar to a family member or friend I would say that the lecture was on the challenges or making a compound with a ring structure similar to a steroid for pharmaceutical use.

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