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!
Base-Catalyzed Hydrolysis of Amides Amides are the least reactive derivatives of carboxylic acids because the conjugate base of an amine, formed in a nucleophilic substitution reaction, is a poor leaving group. For example, in the reaction with a hydroxide, we … Read more
Preparation of Amides Amides can be prepared from acyl chlorides, esters, and carboxylic acids. The most straightforward should be the reaction with acid chlorides since they are the most reactive carboxylic acid derivatives, and amines are good nucleophiles too. This … Read more
Preparation of Anhydrides Anhydrides are prepared by dehydration of carboxylic acids either at extremely high temperatures (800 oC) or by using P2O5 as a dehydrating agent: For most carboxylic acids are not compatible with excessive heating, and even … Read more
This article summarizes the main reactions of esters with associated practice problems. We covered the mechanism and other details about each reaction, so if you need to go over them, click on the corresponding links. Let’s start with the hydrolysis … Read more
Esters can be converted into primary, secondary, and tertiary amides by an aminolysis reaction with ammonia, primary amine, and a secondary amine, respectively: The reaction goes by a nucleophilic addition-elimination mechanism, and alkoxy groups (RO–), being poor leaving … Read more
Reduction of Acyl Chlorides to Alcohols Acid chlorides can be reduced to alcohols by lithium aluminum hydride (LiAlH4) and sodium borohydride (NaBH4). In both reactions, there is an aldehyde intermediate formed, and therefore, the reducing agent is used … Read more
Alright, so we learned about the Fischer esterification from carboxylic acids and alcohols and their hydrolysis in acidic or basic conditions but what is transesterification? Transesterification is the conversion of one ester to another – simple: Just like … Read more
We have seen that all the steps in the Fischer esterification are reversible and the equilibrium is shifted toward the ester product by using an excess of alcohol. This nature of the reaction allows to hydrolyze esters back into a … Read more
Fischer esterification is the acid-catalyzed reaction of carboxylic acids and alcohols: Before we get into the details of this reaction, remember that there are other ways of preparing esters. For example, the carboxylic acid can be converted into … Read more
Acyl chlorides are very useful in reactions with organometallics because they can selectively be converted into alcohols or ketones. For example, Grignard reagents will react with acyl chlorides to produce alcohols, while organocuprates (Gilman’s), also known as lithium dialkyl cuprates, … Read more
