In the following posts, we will learn about and do many practice problems on Nucleophilic Substitution Reactions. Nucleophilic Substitution Reactions are one of the most important major classes of organic chemistry and essential that you build a solid foundation and understanding of their principles and mechanisms such as the SN1 and SN2 reactions.
We will start from the introduction and general features of Nucleophilic Substitution Reactions and go in detail individually for the SN1 and SN2 mechanism. Each practice problem is designed to address the specifics of these mechanisms; the reactivity, stereochemistry and possibility of rearrangements. For example, you will have many practice problem examples that demonstrate in detail the inversion of R and S configuration during SN2 reactions. On the other hand, we will also see why a racemic mixture is obtained when the reaction goes by the SN1 mechanism via the formation of a carbocation intermediate.
One important and yet overwhelming questions in Nucleophilic Substitution Reactions is the prediction of the mechanism as to whether it is SN1 or SN2. And we will talk about how to choose between SN1 and SN2 considering the nucleophile, the substrate, the solvent, and the reaction conditions. Once you have sufficient knowledge, we will so do the retrosynthetic analysis of Nucleophilic Substitution Reactions to learn the best of choosing a reagent for functional group transformations.
Your professor has been talking about the SN2 reaction, and you have got the key principles such as the curved arrow mechanism, inversion of configuration, and second-order reaction, but there was one phrase that left you wondering: “concerted mechanism”. So, … Read more
The SN2 (Substitution Nucleophilic Bimolecular) reaction involves a single concerted step, where the nucleophile attacks the carbon bearing the leaving group from the backside, and the leaving group departs simultaneously. As an example, let’s show the reaction between 2-bromobutane and … Read more
Nucleophile and Electrophile – The Terminology From general chemistry, we know that covalent bonds between atoms are formed by sharing two electrons. So, let’s imagine separating these atoms by giving both electrons to only one of them. One becomes an … Read more
Let’s understand the most common words you have been hearing the past couple of days that will last towards the end of the semester: Substitution and Elimination ReactionsSo, what are we substituting and eliminating?These terms refer to the halogen and … Read more
Alcohols can serve both as a nucleophile and an electrophile (substrate) in SN1 and SN2 reactions. However, by themselves, alcohols are not great for any of these reactions because 1) they are weak nucleophiles and 2) the OH is not … Read more
Sterics or steric interactions are the obstructions caused by the size of neighboring groups and atoms. In other words, it is simply two or more atoms/molecules/groups getting in each other’s way because of the tight space. So, how does stereics … Read more
You are here because you have almost figured out what polar protic and aprotic solvents are, but want to clearly understand what they have to do with SN1 and SN2 reactions, isn’t that right?To answer and understand this, let’s first … Read more
Carbocations are electron-deficient species, as the carbon atom is surrounded by only three bonds with no lone pairs. Remember, the standard bonding pattern of carbon is 4 bonds with no lone pair: So, how can we stabilize the … Read more
We have seen many times in SN1, SN2, E1, and E2 reactions that halogens, more specifically, their ions called halides, are the leaving group.A common question many students wonder about, and make the mistake of, is whether an OH group … Read more
