Enantiomers and diastereomers are the only two stereochemical relationships that you can have between any two molecules. The stereoisomers are any two molecules that fulfill the following two requirements: Both molecules must have the same molecular formula, and Both molecules must have the same atom connectivity. So, what’s the difference then? The molecules are stereoisomers …
Pinacol rearrangement is a specific elimination reaction that vicinal diols go through in acidic conditions. Unlike a typical E1 reaction that gives you an alkene, the pinacol rearrangement gives you an aldehyde or a ketone instead. Here’s the general scheme for the reaction: As you can see, the pinacol rearrangement also causes the carbon backbone …
The Staudinger reaction is a mild reduction of organic azides yielding corresponding primary amines. The reaction has been developed by Hermann Staudinger in 1919 when he was a professor at the Swiss Federal Institute of Technology in Zürich. In the Staudinger reaction the azide reacts with triphenylphosphine yielding the corresponding iminophosphorane intermediate similar to the …
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 …
