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.

Carrots get their orange-y color from, you guessed it, an organic chemical. This chemical, called beta carotene, gets its pigment from its conjugated electron system. We’ve talked some already about conjugation, but in this episode of Crash Course Organic Chemistry we’ll go even deeper and look at how conjugation stabilizes molecules and how p orbitals can overlap to form pi molecular orbitals of different energy levels. Plus we’ll learn what UV spectroscopy can show us about conjugated molecules.

We’re going back to the lab! So far we’ve learned some important lab techniques that organic chemists might use day to day, like chromatography and proton NMR, but there are even more to learn. In this episode of Crash Course Organic Chemistry, we’ll introduce some new lab techniques such as distillation and recrystallization and apply them to everything we’ve been learning about EAS reactions. And we’ll do some synthesis problems!

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.

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!

If you’ve been paying attention so far in this series, you’ve probably heard of benzene. This molecule is flat, cyclic, and belongs to a special class of compounds known as aromatics. In this episode of Crash Course Organic Chemistry, we’ll learn all about aromatic compounds, their properties, reactivities, and some of the most important examples, like benzene. We’ll also revisit our friend NMR, and hear about some dubious science history!

So far in this series we’ve focused on molecules with tens of atoms in them, but in organic chemistry molecules can get way bigger! Polymers are molecules that contain hundreds, thousands, or even millions of identical subunits. In this episode of Crash Course Organic Chemistry, we’ll look at different examples of addition and condensation polymers, learn about different types of polymerization, and see how a polymer’s morphology affects its properties. Plus we’ll see how some of the polymers we encounter every day were discovered by accident!

As we construct more complex organic molecules, it can start to feel like decrypting a complex code. Organic synthesis takes simple starting materials, and turns them into complex structures, and reverse engineering can help us figure out the steps in between. In this episode of Crash Course Organic Chemistry, we’ll practice multistep synthesis problems, learn about how we can use retro synthesis to make more complex molecules, and use liquid-liquid extraction to separate solvents. As always, we’ll work through examples and connect everything back to our Mold Medicine Map!

Things have been getting more and more complicated here in Crash Course Organic Chemistry, and as we deal with more complex molecules, parts of molecules we don’t want to react will start reacting along with the parts that we do. Luckily, we have protecting groups, which act like a chemical disguise and help us control how molecules react. In this episode, we’ll look at what makes a good protecting group, as well as identify some good protecting groups for different functional groups. We’ll also see what role protecting groups play in the synthesis of penicillin!

We get it, learning so many different organic reactions is probably giving you a headache, but hopefully this episode can help! We’re getting even deeper into carboxylic acid derivatives, some of which are used in common headache relieving painkillers. In this episode of Crash Course Organic Chemistry, we’ll learn how to convert more reactive carboxylic acid derivatives into less reactive ones, turn carboxylic acids into acid chlorides, reduce carboxylic acid derivatives using metal hydrides, and more! Plus, we’ll get to add the first stage of synthesizing Penicillin V to our Mold Medicine Map!

Esters have a wide range of uses, from giving perfumes and colognes their fragrances, to preventing diseases like scurvy. Vitamin C, that scurvy preventing antioxidant, is derived from carboxylic acids, a class of organic compounds we’ve already learned a lot about! In this episode of Crash Course Organic Chemistry, we’ll look at four different carboxylic acid derivatives and their reactivities, react them with nucleophiles, and learn some hydrolysis reaction mechanisms that we can use in our synthesis of penicillin!

What do the smells of feet, armpits, vomit, and goats all have in common? (Besides being super gross…) Carboxylic acids! Despite being responsible for some of our least favorite odors, carboxylic acids are also super useful in organic chemistry. In this episode of Crash Course Organic Chemistry, we’ll review carboxylic acid synthesis and nomenclature, react carboxylic acids to form salts, esters, and acid chlorides, and start our journey towards synthesizing one of the most important organic chemicals in medicine, penicillin!

We’ve already learned the basics of carbonyl chemistry and talked about how we can synthesize aldehydes and ketones, but there’s still so much more to learn, like the role carbonyl groups play in reactions involving sedatives! In this episode of Crash Course Organic Chemistry we’re diving deeper into aldehydes and ketones by focusing on addition reactions of oxygen and nitrogen based nucleophiles. We’ll cover hydrates, acetals and hemiacetals, imines and enamines, and more!

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.

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.

Even though all living things have a lot in common, different organisms can have very different reactions to the same organic chemicals. That means it’s really important for organic chemists to be able to purify chemicals and separate the products we want from reactions, from the side products we don’t. In this episode of Crash Course Organic Chemistry, we’re heading into the lab to learn about one of the ways we can separate chemicals in a mixture: chromatography!

What comes to mind when you think of alcohol? Probably alcoholic drinks like beer or wine. But in organic chemistry alcohols are an important and versatile family of compounds. In this episode of Crash Course Organic Chemistry, we’ll use alcohols as a starting point to get other types of compounds like ethers, epoxides, and more!

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!

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.

We’ve already learned a bit about substitution reactions in organic chemistry and the two different paths they can follow: SN1 and SN2. In order to better predict the products of a substitution reaction and understand how they work, we need to be able to figure out which mechanism a reaction is likely to follow. In this episode of Crash Course Organic Chemistry, we’ll deepen our knowledge of substitution reactions by looking at factors like substrate structure and reaction conditions to determine whether SN1 or SN2 is the more likely mechanism.

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.

Throughout this series we’ve mostly talked about pairs of electrons, but electrons don’t always have a buddy. An atom or group of atoms with a single unpaired electron is called a radical. In this episode of Crash Course Organic Chemistry, we’ll learn all about radicals including the three key steps in a radical reaction and Hammond’s Postulate, an important tool to help us understand these reactions. We’ll also see ways radicals can react with alkanes, alkenes, and alkynes.

Carbon-carbon double bonds are pretty common in nature, but triple bonds between carbons, called alkynes, are not. When alkynes do pop up in nature, it’s usually in a compound that’s toxic to humans, however, we can synthesize alkynes that are life saving medicines and materials. In this episode of Crash Course Organic Chemistry, we’ll learn about alkynes and some of the reactions we can use them in (hint: it’s a lot of the same reactions we used for alkenes!)

Oxidation-reduction reactions are going on around us, and inside us, all the time, and we can make redox reactions in organic chemistry easier to understand by tracking carbon-oxygen bonds. In this episode of Crash Course Organic Chemistry, we’ll focus on alkene redox reactions and revisit our 3-part secret handshake to help us better understand patterns and predict the products of these reactions.

Like a trendy dance, a fighting combo, or a secret handshake, organic reactions can be broken down into simpler steps. In this episode of Crash Course Organic Chemistry, we’ll specifically be looking at alkene addition reactions and with each new reaction ask ourselves three questions to help us puzzle through the mechanism and understand what’s going on.

In organic chemistry, different reactions can take place at vastly different speeds. To better understand whether a reaction actually will happen, and how useful that reaction is, we need to understand thermodynamics and kinetics. In this episode of Crash Course Organic Chemistry, we’ll review some important concepts from general chemistry, learn how to draw energy diagrams, go over the difference between an intermediate and a transition state, and get an introduction to catalysts.

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.

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.

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!

Acidity is a tricky concept, and it’s not always like how we see it in the movies. As organic chemists, we need to know how to predict the strength of weak acids and bases. In this episode of Crash Course Organic Chemistry, we’ll learn four key factors that we can use to predict relative acidity. This important tool will help us us to predict the products of chemical reactions.

We’ve all heard the phrase “opposites attract.” It may or may not be true for people, but it’s definitely true in organic chemistry. In this episode of Crash Course Organic Chemistry, we’re learning about electronegativity, polarity, resonance structures, and resonance hybrids. We’ll practice a very important skill for this course that will help us avoid a lot of memorization in the future: electron pushing. It’ll be a lot of trial and error at first, but we all start somewhere!

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.

The shape of molecules is super important to life as we know it. In this episode of Crash Course Organic Chemistry we’re learning about stereochemistry and how to identify molecules as chiral or achiral. And as always, we’ll be doing a lot of practice!

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.

Alkanes are kind of the wallflowers of organic chemistry, but they still have important functions in the world around us. In this episode of Crash Course Organic Chemistry we’re building our knowledge of organic molecules by learning all about these so called couch potatoes from how they are separated from crude oil to how to use Newman projections to predict torsional strain and steric hinderance. We’ll also learn the names of some common conformers and get an introduction to cycloalkanes.

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!

The organic molecules that make up life on Earth are more than just the 2-D structures we’ve been drawing so far. Molecules have 3-D shapes that help us understand what they can do. In this episode of Crash Course Organic Chemistry, we’ll learn how orbital hybridization and valence bond theory can help us explain 3D molecular structures and about constitutional and geometric isomers.

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.

Language is complicated, especially in organic chemistry. This episode of Crash Course Organic Chemistry is all about nomenclature. We'll dive into IUPAC systematic naming of organic molecules, and get to practice with the help of three trusty steps!

Organic chemistry is pretty much everywhere! In this episode of Crash Course Organic Chemistry, we’re talking about the amazing diversity among organic molecules. We’ll learn about the origins of organic chemistry, how to write Lewis structures, condensed structures, and skeletal formulas, and what gross organic compound the Romans used to dye their fabrics pretty colors.