Hexagons appear all over the natural world from honeycomb to bubbles, and they even appear in organic chemistry! In this episode of Crash Course Organic Chemistry, we're learning all about cyclohexanes, including how rings pucker to relieve strain, the boat and chair conformations, and how ring flips can switch substituents from axial to equatorial. We'll practice a lot of chair flips, but don't flip an actual chair just yet! Lots of practice is key to understanding organic chemistry's favorite manifestation of the hexagon.

Organic chemistry isn’t that different from an adventure game, with substrates as characters, nucleophiles as magic potions, and reaction conditions as different magical kingdoms. In this episode of Crash Course Organic Chemistry, we’ll learn the tricks to this game so that we can figure out which transformation, or mechanism, will occur when we combine any substrate with any nucleophile. Let’s go on an adventure!

Have you ever wondered where cured meats like salami or pepperoni get their bright red color? Of course its from organic chemistry! A chemical called nitric acid gives them that bright color, while also increasing their shelf. It's also involved in some other interesting reactions. In this episode of Crash Course Organic Chemistry we'll see how nitrous acid reacts with primary amines to form diazonium salts, we'll learn about alkyldiazonium salts and aryldiazonium salts, and see what conditions are necessary for nucleophilic aromatic substitutions.

Going out in the sun can work wonders for your mood, but unfortunately too much UV exposure can do serious damage to your DNA. This damage occurs through a type of organic reaction called a pericyclic reaction. In this episode of Crash Course Organic Chemistry, we’ll explore pericyclic reactions to see how the sun can both give us life, and hurt us, and also look at other important pericyclic reactions, such as the Diels-Alder reaction.

We’ve spent the last few episodes talking about substitution reactions, but now it’s time to talk about a related type of reaction: elimination reactions! Elimination reactions are super important because they are the main way we can make compounds with double and triple bonds in organic chemistry. In this episode of Crash Course Organic Chemistry we’re going to cover… a lot, including a review of substitution reactions, E1 and E2 mechanisms, Zaitsev’s rule, and more. And of course, we’ll finish with some practice problems.

Alkenes are an important type of molecule in organic chemistry that we’re going to see a lot more of in this series. But before we can really get into the many cool reactions alkenes do, we need to go over some of the basics. In this episode of Crash Course Organic Chemistry, we’ll review and build on our knowledge of alkene nomenclature, revisit our friend the carbocation, and learn Markovnikov’s Rule: an important tool that will help us predict the products of addition reactions involving alkenes.

You may know that cows produce methane, which is a big concern when it comes to global heating, but did you know that organic chemistry provides a potential solution to this problem? Feeding cows small amounts of red seaweed can greatly reduce methane emissions, in part due to organic chemicals called enols! In this episode of Crash Course Organic Chemistry, we’ll learn all about enols and enolates, their reactivity, and reactions we can do with them including halogenation and alkylation.

If you were given a chemical and told to identify it, how would you go about doing that? You could look at different factors like color, boiling point, melting point, or smell, but the answer still might not be clear. Thankfully, today we have a more precise, higher-tech way of identifying chemicals called Nuclear Magnetic Resonance, or NMR. In this episode of Crash Course Organic Chemistry, we’ll look at how NMR allows us to visualize a molecule as a spectrum, and what the peaks on the spectrum tell us about the structure of the molecule.

It’s time for molecular analysis! On this episode of Crash Course Organic Chemistry, we’re learning about mass spectrometry and infrared spectroscopy through the lens of a forensic investigation. Put on your lab coats, and let’s solve this mystery!

We’ve talked about benzene a bit already in this series, but did you know that benzene rings are present in all kinds of familiar substances? The styrofoam packaging that comes with new appliances, some pharmaceuticals, pesticides, and even some explosives contain benzene. In this episode of Crash Course Organic Chemistry, we’ll see how we can use electrophilic aromatic substitution to attach stuff to benzene rings like halogens, carbons, and more!

When we venture to new places, we need navigational tools to guide us. In organic chemistry, those are reaction mechanisms! In this episode of Crash Course Organic Chemistry, we’ll learn all about how to write reaction mechanisms. Having this super useful skill means we don’t have to worry about memorizing every reaction that has ever existed.

Substitution reactions can have really powerful effects, both good and bad, in our bodies. You might remember substitution reactions as displacement reactions from general chemistry, but (you guessed it!) in organic chemistry they’re a bit more complicated. In this episode of Crash Course Organic Chemistry, we’ll learn about the two pathways substitution reactions can take: SN1 and SN2 mechanisms, which substrates prefer which mechanism, and we’ll apply this knowledge by looking at how substitution reactions make chemotherapy treatments work.

These days, we don't have to worry too much about meeting an early demise from ulcers, breaks in the stomach lining that could be fatal back in the early 1900s. This is because we have medicines to treat them, like proton pump inhibitors! In this final episode of Crash Course Organic Chemistry, we'll look at medicinal chemistry by breaking down how penicillin fights bacteria, how proteins are made both in the body and in the lab, and we'll finally finish our synthesis of penicillin V and complete our Mold Medicine Map! Hopefully this series has shown you the many ways organic chemistry is all around us and how it can help us to better understand ourselves, and improve our world!

We’ve already learned a lot about electrophilic aromatic substitution (EAS) and benzene, but guess what? There’s even more to learn! In this episode of Crash Course Organic Chemistry we’ll revisit our old friends the Friedel-Crafts reactions and learn some of their limitations and look at where substitution happens when there are multiple directing groups on a benzene ring. Plus we’ll introduce some benzylic reactions!

In the previous episode we discussed what happens when we use electrophilic aromatic substitution to add a group to a benzene ring, but what happens when you try to add even more groups? Well, things get a little more complicated. In this episode of Crash Course Organic Chemistry, we’ll continue our exploration of EAS reactions by looking at electron donating groups and electron withdrawing groups on benzene, and how they affect what happens when we try to add new groups to the ring.

Oxygen is pretty dang amazing! Some of the most intensely studied functional groups in organic chemistry have oxygen atoms. In this episode of Crash Course Organic Chemistry, we're building on the last episode's discussion of nomenclature by learning about IUPAC's naming rules for even more functional groups.

Enantiomers have almost all the same chemical and physical properties, so it can be tough to separate them. But it’s still super important that we know how to tell them apart! In this episode of Crash Course Organic Chemistry, we’ll recap all the types of isomers we’ve learned about so far, and also learn about polarimetry as a way to separate enantiomers and how to predict the number of stereoisomers a molecule will have.

Organic reactions are kind of like carefully choreographed fight scenes, and nucleophilic attack is a key move. This episode of Crash Course Organic Chemistry is all about nucleophiles and electrophiles, or what happens at those molecular hot spots we’ve been talking about. We’ll also learn about what IR spectra can tell us about reactions, and how cyanide is more than just a poison from mystery stories. Let’s get to it organophiles!

Have you ever wondered why the gas station has “unleaded fuel” but there isn’t a “leaded” option? The answer has to do with a chemical called tetraethyl lead, which is an organometallic compound, or an organic compound with a carbon-metal bond. In this episode of Crash Course Organic Chemistry, we’ll learn all about organometallic compounds, including what they are and what kind of reactions we see them in. But beware! This class of compounds may be super useful, but also has a dark side.

Ketones and aldehydes are all around and inside us, from the strong smelling component of nail polish remover, acetone, to hormones in our bodies, to drug treatments for allergies, COVID-19, and even cancer! We’ve already learned a bit about aldehydes and ketones in this series, so in this episode of Crash Course Organic Chemistry, we’ll review some of that knowledge and start to go even deeper.