Topic 14: Nucleophilic addition to carbonyl compounds

14.1What is a carbonyl group?
 
14.2What is a carbonyl compound?
 
14.3What two categories does your author propose to use to distinguish between types of carbonyl compounds based on their reactivity?
 
14.4What is the outcome when a nucleophile and an aldehyde or ketone react? What is the technical name of this reaction?
 
14.5What is the outcome when a nucleophile and a “carboxylic acid derivative” react? What is the technical name of this reaction?
 
14.6What is the outcome when a nucleophile such as hydroxide and a carboxylic acid react? What is the technical name of this reaction?
 
14.7So, aren‘t there three fundamental types of carbonyl compound in terms of how they react with a nucleophile?
 

Topic 15: Reduction of carbonyl compounds

15.1Both NaBH4 and LiAlH4 reduce aldehydes and ketones to hydroxy compounds. Why would a chemist in the lab prefer one over the other? What is the underlying principle here?
 
15.2If NaBH4 and LiAlH4 were assigned personalities, which would be the “gentle, but effective, one,” and which would be the “Get out of my way, I‘m coming through NOW!” one? See, for example, https://tinyurl.com/y77ntyjy. Any idea why this might be?
 
15.3The exact mechanism of reduction with NaBH4 and LiAlH4 is not known (despite what your book might say). The real mechanistic question is this: Is this reaction reversible or not? What do you think? Is it OK to just think of this as “H−”, the same way as we speak of “Br+” or “H+”? Why or why not? What reagent does in fact act exactly and only like H− in terms of only being a very strong base?
 
15.4What is the design idea behind the invention of diisobutylaluminum hydride (DIBAL-H) or lithium tri-tert-butoxyaluminum hydride? Where have you seen this before? (Give at least three examples, probably out of Chapters 11 or 12.)
 
15.5What is the difference in result when one uses one of these reagents instead of LiAlH4 on a carboxylic acid derivative such as an acid chloride or ester?
 

Topic 16: Oxidation of carbonyl compounds

16.1Why is only the oxidation of aldehydes discussed in this chapter in relation to the oxidation of carbonyl compounds?
 
16.2Can you think of any reaction you have learned that can oxidize a ketone to a carboxylic acid?
 
16.3What‘s special about Ag2O/NH4OH?
 
16.4What is “NH4OH”, by the way?
 
16 questions
472 questions for Organic II

472 Questions for Organic II

Dearest Student. This web page is a set of questions I call Detailed Intended Learning Outcomes For Organic Chemistry (Part II). Some time ago I asked myself, "Bob, what do you think are the key questions that you hope students will be able to answer after taking Chemistry 248 at St. Olaf College?" So here you have them. Some are very simple; some require more thought. All are good questions to be thinking about as you read, discuss, and master the practical aspects of organic chemistry. They are discussion starters and review tips. There are no answers here (though there are some clues). The questions are here to help you focus on what's important (to me, at least!) and organize your learning process. The questions are grouped into topics. Bite-size chunks. Take them a few at a time. Don't feast on them all at one sitting!

(preliminary version 2021.01.15 feeback: Bob Hanson)