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!
We have seen that carboxylic acids can be reduced with LiAlH4 and boranes to primary alcohols. We also know that esters, nitriles, and acid chlorides can be reduced to aldehydes using DIBAL or at lowered temperatures (typically -78 oC): … Read more
There are direct ways of converting alkenes to amines covered in undergraduate organic chemistry textbooks, so a question like this is most likely meant to test your knowledge on multiple functional group transformations. The strategy here is to … Read more
In the previous post, we discussed ring expansion rearrangements where 4 and 5-membered rings were transformed into more stable, larger rings. Sometimes, the process goes in reverse direction, and larger rings are transformed into smaller rings. These are … Read more
Amides are the least reactive derivatives of carboxylic acids, so reducing them requires using the strong reducing agent LiAlH4. The reduction converts primary, secondary, tertiary cyclic, and acrylic amides to corresponding amines: The Mechanism of Amide Reduction by … Read more
Carboxylic acids can be reduced to primary alcohols using an excess of strong reducing agents such as lithium aluminum hydride (LiAlH4 or LAH). As sodium borohydride (NaBH4) is the most common reducing agent we learn about together with … Read more
Let’s address two common exam questions: comparing the SN2 and E2 rates of two isomeric cyclohexanes and determining the major product in those reactions. The first thing you need to remember here is that both SN2 and E2 … Read more
Acetylide ions are the conjugate bases of terminal alkynes: What makes them different from the conjugate bases of alkanes and alkenes is that they are easier to prepare and use in other reactions. The reason for this is … Read more
Alkenes are converted to alkyl halides by the addition reactions of hydrohalic acids (HCl, HBr, HI). These are generally Markovnikov additions unless we direct the Br to the less substituted carbon atom radical addition using a peroxide catalyst: From reaction … Read more
The dehydrohalogenation of alkyl halides gives alkenes. For example, we can react alkyl halides with strong bulky and non-bulky bases to prepare the Zaitsev or Hofmann alkene: Preparation of Alkynes As the name suggests, in these dehydration reactions, … Read more
Alkyl halides can be converted to alkenes via elimination reactions using strong and weak bases. These conversions are also known as dehydrohalogenation reactions: The elimination reactions are most often achieved by using strong bases, and there are several … Read more
