The only way of mastering any topic in Organic Chemistry is doing lots of practice problems. And I know, seeing my students, that starting to work on a practice problem may be the hardest part as you don’t know where to start. It is difficult to visualize what where the double bond would be moved if you follow the five curved arrows crammed in one step. Here is the trick:
We are always told to think before doing something. Fair enough. But let me tell you, it is also strangely enough, that in Organic Chemistry, it is often better to draw and then think about what you did (not in the lab though). It is much easier to have a structure in front of you and check for errors and improvements.
Do the first step, take the pencil and you will see that the ball gets rolling.
You have all these Organic Chemistry Practice Problems waiting to be solved!
Why are they Called Addition Reactions? Let’s first understand why the reactions of alkenes are called addition reactions. The general formula of alkenes is CnH2n which is two hydrogens less than alkanes (CnH2n+2). This means alkanes are saturated as there … Read more
Halohydrins are compounds containing a vicinal (adjacent) halogen and a hydroxyl groups. Halohydrins are prepared by the traction of alkenes with halogens in the presence of water: Recall that in neutral solvents such as CCl4 and DCM, the … Read more
Addition of HBr, HCl, and HI to Alkenes The regiochemistry of regioselectivity of a reaction is the preferential formation of one out of two or more possible regioisomers. For example, when an unsymmetrical akene is reacted with a hydrohalic acid … Read more
Acid-Catalyzed Addition of Alcohols and Alkoxymercuration Alkenes can be converted to ethers by reacting them with alcohols in the presence of acid or using Hg(OAc)2 catalyst. You may wonder why use a toxic mercury catalyst if it … Read more
There are two main ways of converting alkenes to alcohols, and both are hydration reactions of alkenes. One is the acid-catalyzed hydration of alkenes, and the other is the hydroboration-oxidation of alkenes. An important difference between these methods is the … Read more
Markovnikov’s Rule In the previous post, we talked about the addition reaction of hydrogen halides (HCl, HBr, and HI) to alkenes, and learned about Markovnikov’s rule, which states that in these reactions, the halogen adds to the more substituted carbon … Read more
Double bonds are electron-rich and therefore they react with many electron-deficient species, including acids such as HCl, HBr, and HI. The products of these addition reactions of HX acids to alkenes are alkyl halides: These are hydrohalogenation reactions, … Read more
We have learned that a Newman projection represents a molecule viewed from a specified direction and a given bond. Therefore, a molecule can have multiple Newman projections depending on this bond and the direction we are looking from. For example, … Read more
Although quite similar and often used interchangeably, steric and torsional interactions have different definitions. 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/groups getting in each … Read more
Conformational analysis is the study of the relative stabilities of different conformations of a molecule. Recall that conformations or conformers are different spatial arrangements of atoms in the molecule, which are achieved as a result of rotations about single (σ) bonds. … Read more
