There are two terms that describe the stereochemical outcome of reactions. These terms are stereospecific and stereoselective. And due to the similarity in the terms, many students have a hard time remembering which one is which or even know the difference. So, let’s look at these two terms in a little more detail. Stereoselective Reactions …
By resonance in organic chemistry we mean an interaction of multiple p-orbitals making a long π-bond spanning multiple atoms. A case of a simple π-bond results from the interaction of the two p-orbitals connecting two atoms. However, there are situations when three or more orbitals can interact making a much longer and much more complex …
Organic chemistry, as a science, has its own “written language” that we use to communicate the ideas in OChem. You have already seen molecules before in general chemistry and are familiar with some types of molecular representations. Let’s go over the typical ways we draw molecules in organic chemistry and discuss their pros and cons. …
You’ve probably heard about the hybridization in your general chemistry course and in the organic chemistry multiple times. So, what’s the fuss all about? We all know from general chemistry that the s-orbital is spherical, and p-orbitals are dumbbell-looking orbitals oriented along the x, y, and z axes of the Cartesian system. We also know …
Constitutional isomers are molecules that have the same molecular formula but they have a different connectivity of atoms in the molecules. It’s best if I illustrate the idea of constitutional isomers with an example. Suppose, we have a molecule with a molecular formula C2H6O. Building the Lewis structures for this molecule reveals the two possibilities …
VSEPR stands for Valence Shell Electron Pair Repulsion Theory. VSEPR is an important part of the valence bond theory and is a logical next step in the use of the Lewis structures in organic chemistry. In this post, I’m only going to focus on the uncharged molecules. However, the formal charge doesn’t really change anything …
Lewis structures are a simple and the most common way we represent molecules. We show electrons around the atoms with dots: The number of dots equal to the number of valence electrons an element has. The number of valence electrons correspond to the group in which you find the element. Thus, B has 3 valence …
Naming alkanes is one of the first topics you’re going to cover in your organic chemistry course. Nomenclature of alkanes is not particularly difficult but it can be tricky and tedious. Here are some basic rules we use for the alkane nomenclature. All names of alkanes are built from the list of parent names. You …
In this post I want to go over the three most typical forms of the carbohydrates: Fischer projection for the open-chain molecules, Haworth projections focusing on cyclic pyranoses, and your regular chair conformations. While other structures are possible (and you’re definitely going to encounter them in your course), I’m specifically going to be focusing on …
Converting Between Fischer, Haworth, and Chair Forms of Carbohydrates Read More »
