[NUS Module Review] CM2121: Organic Chemistry 2

CM2121: Organic Chemistry 2

(INTRODUCTION)

I think this module needs no introduction. The most tedious and crazy-filled chemistry module you will ever get. I say this because I'm sure many people actually turn crazy studying this module alone. Heh, just kidding. But on a serious note, if you ever think that Grignard, Stereochemistry, SN1/SN2 and E1cB are hard (if you can't recognise these terms you're so in deep sh*t for this module), you are in for a whole new roller-coaster ride in this module. If you think I'm joking, just know that there are quite a number of people who retains for this module. 

(LECTURERS)

This module is mainly taken by Prof Yao Shao Qin. Okay, I gotta get one thing clear, especially to those who have done this module and experienced his style of teaching. Prof Yao's examinations and tests are relatively quite easy. And I'm not saying this because I'm good at Organic Chem. But comparing to Dr Zhang Sheng's papers, the difference is seriously night and day. Even if Prof Yao's papers are hard, it is still doable compared to Dr Zhang Sheng's paper, which trust me, it's really a killer. 

Nonetheless, when it comes to teaching style, Prof Yao teaches really fast. At first, he will teach relatively slow. But he does warn you that the speed of teaching will increase gradually in the future chapters. And true enough, he will increase his speed and if you can't catch up, then too bad for you. The bad part - Most of the topics are interlinked with each other. So if you don't understand something, you best clarify immediately, because it will be hard to catch-up in the subsequent chapters.

No information can be given on Dr Zhang Sheng for his lecturing because this module is totally lectured by Prof Yao. However, there are some semesters where Dr Zhang will be lecturing so good luck with that. :) Instead, Dr Zhang teaches the tutorials and as usual, he is always testing students' knowledge beyond the scope of the module. He will always give alternatives to the answers provided by the textbook and he is a super caring tutor.

(EXPANSION OF TOPICS COVERED)

As far as topics are concerned, the lecturers do expect you to know your CM1121 topics. Yes, that means everything from Grignard to E1/E2/E1cB to reductive amination. These concepts will not be covered in CM2121 but will be mentioned throughout the tutorial exercises or showing certain examples during lectures.

New topics mentioned will include:

• Enolate formation and reactions (Around 3 - 4 chapters)
• Reduction, Oxidation reactions
• Protection Groups
• Julia Olefination
• Retrosynthesis (i.e Backwards of a Synthesis)
• Drawing Diastereomers (i.e Felkin-Ahn, Houk, Zimmerman)
• IR Spectrometry and NMR

For exams, there will definitely be a question on Retrosynthesis, one question on IR/NMR and one or more questions about diasteromer drawing. So beware for these topics okay. They are essential to study for your finals. They might be difficult at first, but do your best to understand them.

(SCHEDULE)

The lectures are usually held twice in a week, both 2 hours long. Prof Yao loves to drag and utilize close to 1 hour and 45 minutes because that's how much content is needed to be covered per lesson. I highly recommend that you attend the lectures because it really helps clear lots of doubts. Try to copy some notes if you find yourself falling asleep, which will happen really often in Organic Chem, TRUST ME!

Tutorials are held once per week for only 1 hour. It is not compulsory but it is highly recommended that you come. Because it is reallyyyyy useful.

Lectures are NOT webcasted.

 (PASSING THE ASSESSMENT)

You know I really think that everyone can pass organic chemistry if we put our minds into it. It's hard to get an A but it's also hard to fail. For those of you who have done CM2121 and think I'm joking, do hear me out. First of all, their marking leniency is really quite good. I could get a reterosynthesis question wrong and still get a 3/5 marks for it. What you must show is that you understand the concept. Secondly, all the tests and exams are open book. So if you're really lost, just open the book, copy and apply the concepts. It's that easy. You need to have 0 clue in organic chemistry to fail the module, but seriously, I think it takes some skill to fail also ah.

With that said, lets look at the breakdown of CAs and final percentages:

• 3 choose 2 CAs - 20% each ~ total 40%
• Finals - 60%

Looks pretty simple, but it's not. Lots and lots of hard work is needed to do decently well in this module. The first CA should cover the chair and boat structure and some recap of some knowledge from CM1121. The second CA should cover up to the end of the enol chapters. The last CA will cover until the end of reterosynthesis. Most questions in CAs are REPEATED FROM PREVIOUS CAs. Sooooo, my advice is study smart ya! ;P

Unlike the CAs, the finals consist of no repeated questions from previous CAs/finals as it is not allowed. Hence, you really need to rely on your skillful search of your textbook, your own knowledge or both to do well for this paper.

(EXPERIENCE AND FINAL GRADING)

Okay, so Prof Yao did mention on the first day of lecture that out of 3 CAs, 2 will be graded. However, unlike previous years, they will no longer take the best two CAs. Instead, Prof Yao said that he will decide which 2 out of 3 CAs he will consider into the marks and he won't tell us which one... Hmmmm... Sounds a lil fishy here. Carry on.

So I thought that maybe Prof Yao decided that maybe he should reduce the number of students retaining this semester by letting CA1 and CA2 be counted and then CA3 be like a practice paper for the final exam. After all, CA1 should be the easiest of the 3. What a good way to give out free marks right? But noooo. *This is NUS Chem major, I/We shouldn't be expecting such nice treatment*

And truth be told, I studied really hard for CA1, hoping to get that glorious 20% in that bag. I did past years papers and redid the ones that I got wrong in. Finally, when the day to CA1 came and I entered the lecture hall. I immediately felt a sucker punch from the lecturers. It's the exact same practice paper I did the night before. That means 20% in the bag right? If only Chem modules were this easy. The moment I saw Prof Yao's smirk while we were doing the CA1 I knew that we were just doing an ungraded CA. And true enough, it didn't count.

So that means that for the next 2 CAs, we have to work our brains off to do well. Prof Yao allowed cheat sheets to be brought for the CAs, as well as the textbook to guide us. He even hinted that questions will be repeated from past CAs. So off I go doing past CA2 practice papers, hoping that at least one question would be repeated from there. However, you guessed it... None came out from CA2. Instead, 3/4 of the questions came out from past years CA3 paper. 

And for me, whenever I find myself unable to do a few questions, I will start to panic and just have a mind blank. Across the entire lecture hall, students were either scratching their heads, asking for more hints (which they provided for every question btw) and demanding for more time. And of course, there were some who did past years CA3 paper and were probably laughing so hard inside. During that 1.5 hours of the CA, I did what I knew and guessed the structure based on the formula given. In the end, I got a 12/20, which was the median for the cohort. 

CA3 was a little easier, although this time I came even more prepared. Hehe >.+!! I scored a 16/20 for this CA. Next was finals and I was really scared for this module. This was because the past years papers were quite difficult and hard to score. Out of 5 practice papers I could only get 1 reterosynthesis question right, 0 diastereoisomers question correct and only 1 NMR question correct. 

However, I did manage to do okay for the finals. Though I must admit, I made some careless errors for the NMR and some normal synthesis questions, which costed me around 20 marks(?) but I did manage to get the reterosynthesis question correct and possibly the diastereoisomer question right as well. 

Overall, I did quite okay. Better than I expected, but certainly could have done better. Will I be taking more Organic Chemistry modules? Yes, I will. But I think that this module is really doable and super hard to fail. You just need to try and try and try and try (P!nk - Try).

(CONCLUSION AND TIPS)

This module really emphasizes lots of practice. Without practice, not even your golden memory could save you from this module. I enjoyed this module in general, but then again, I love organic chemistry to begin with. It's truly the reason why I decided to major in Chemistry. 

I do feel that with the right amount of practice of past years CAs and with a good formulation of your cheat sheet (😉), you should be all good for your CAs. For the finals, just stay calm. You have your textbook with you, so if you're stuck, use it. Make your money's worth for your textbook. 

p.s Contact me if you want some home-made summary notes specially made by none other than me :p. Able to summarize reterosynthesis in 15 minutes and reduction/oxidation in 5 minutes. Maybe they're free, maybe they're not... I don't know haha but holla at me if you want em. 

Ratings out of 5⭐:

• Rigor - ⭐⭐⭐⭐⭐
• Degree of doability - ⭐⭐
• Bell Curve (to favour you) - ⭐⭐⭐⭐