For many college students, the phrase “organic chemistry” evokes angst and worry, as the subject can seem daunting to learn, let alone to master. For any chemistry major or pre-med student, this course is a requirement, either for a degree or for admittance into medical school or other graduate study; however, it need not be the torturous experience it is rumored to be. It can be survived, if not enjoyed, with the right approach.

Typically, organic chemistry is taught over the course of two semesters or quarters. The first part introduces key concepts and a few reactions, while the second part elaborates on these concepts and introduces more many reactions. It is the second half, with all of the reactions, that often seems unmanageable. Indeed, the number of reactions discussed would be overwhelming to any student who tried simply to memorize them; however, to the student who understands the underlying mechanisms and principles, the number of reactions covered by the class will seem a lot more manageable.

During the first part of the course, concepts such as sterics, resonance, nucleophilicity, electrophilicity, thermodynamic stability, kinetic stability, and electronic inductive effects are introduced. A great deal of organic chemistry can be explained by understanding these seven concepts and how they are related, and thereby a lot of reactions introduced in the second part of the course will make more sense.

Consider, as an example, the addition of a Grignard reagent to a ketone. Here, a nucleophile (the Grignard reagent) attacks an electrophile (a positively charged nucleus, i.e. the carbon of the ketone group) to form a carbon-carbon bond. Essentially, this reaction involves an electrostatic attraction between a partially positively-charged carbon (the carbonyl) and a partially negatively-charged carbon (the Grignard). Now, consider the reaction of a Grignard reagent with a nitrile, aldehyde, and ester. These three reactions can be explained by the exact same concepts as the Grignard / ketone reaction! Thus, instead of trying to memorize four reactions, a student, with the proper understanding, can apply one mechanism to predict (without much memorization) the outcome of all of these reactions. Even more good news: other classes of organic chemistry reactions lend themselves to the same process!

Consider another example: the dreaded Sn2/Sn1/E1/E2 debate. These are typically the first reactions discussed in any organic chemistry course; however, the principles behind these reactions (nucleophile, good leaving group, steric hindrance) can be applied to the whole course, explaining many reactions later on: for instance, the Sn1 and E1 reactions proceed through a carbocation intermediate. The stability of carbocation intermediates drives many of the organic reactions that are covered in both semesters. Understanding this principle can be as helpful in learning about E1 reactions (first semester) as it can be in learning about allylic cation reactions (second semester).

So, to conclude with some practical advice: AVOID MEMORIZATION! Use your time instead to learn and understand the underlying concepts and reaction mechanisms demonstrated by each type of reaction. You can start doing this by taking Varsity Tutors’ free Organic Chemistry Practice Tests. Our free Organic Chemistry Practice Tests are each a selection of 10 to 12 questions, which will give you a cross-section of topics from Organic Chemistry. You might think of them as little quizzes, which you can use to hone your skills. Once you realize which topics you need to work on learning, you can focus on understanding the underlying concepts that explain them, and not just memorizing chemical reactions. This will give you a deeper understanding of the material and help you survive, if not thrive, in O-chem!