Lesson 968 of 1524
Carbonyl Alpha-Substitution Reactions
An example is the α halogenation of ketones on treatment with Cl 2 , Br 2 , or I 2 in acid solution.
Practice this chapterAn example is the α halogenation of ketones on treatment with Cl 2 , Br 2 , or I 2 in acid solution. The α -substitution reaction of a carbonyl compound through either an enol or enolate ion intermediate is one of the four fundamental reaction types in carbonyl-group chemistry
Alpha bromination of carboxylic acids can be similarly accomplished by the Hell-Volhard-Zelinskii (HVZ) reaction, in which an acid is treated with Br 2 and PBr 3 . Alpha hydrogen atoms of carbonyl compounds are weakly acidic and can be removed by strong bases, such as lithium diisopropylamide (LDA), to yield nucleophilic enolate ions.
example — the α halogenation of ketones on treatment with Cl 2 , Br 2 , or I 2 in acid solution. enol or enolate ion intermediate — one of the four fundamental reaction types in carbonyl-group chemistry. acid — treated with Br 2 and PBr 3.
Worked example
What does “example” mean in Carbonyl Alpha-Substitution Reactions?
- 1Use the wording this chapter gives for example.
- 2The book says: the α halogenation of ketones on treatment with Cl 2 , Br 2 , or I 2 in acid solution.
- 3Do not use the meaning of enol or enolate ion intermediate. That term means one of the four fundamental reaction types in carbonyl-group chemistry.
Result: the α halogenation of ketones on treatment with Cl 2 , Br 2 , or I 2 in acid solution
Why. That is the meaning this chapter gives for example.
Do not swap example and enol or enolate ion intermediate. example means the α halogenation of ketones on treatment with Cl 2 , Br 2 , or I 2 in acid solution. enol or enolate ion intermediate means one of the four fundamental reaction types in carbonyl-group chemistry.
Practice margin
This chapter
A fresh set from this chapter only. Choose 10 or 20. Multiple choice and fill-in, with no repeat inside the set.