Favorskii reaction
<templatestyles src="Module:Hatnote/styles.css"></templatestyles>
The Favorskii reaction is the nucleophilic attack of a terminal alkyne with acidic protons on a carbonyl group.[1] The reaction was discovered in the early 1900s by the Russian chemist Alexei Yevgrafovich Favorskii.[2][3]
When catalyzed by acid, this reaction is called the Meyer–Schuster rearrangement.
Reaction mechanism
A metal acetylide is formed in situ when an alkyne is treated with a strong bases such as a hydroxide or an alkoxide.[4] The metal acetylide then reacts with an aldehyde or ketone to form a propargyl alcohol. When an α-hydrogen is present (as is the case when the carbonyl is an aldehyde), it will tautomerize to the corresponding enone.[5]
Protecting group
This reaction is used to protect alkynes: the alkyne is either converted with acetone to a 2-hydroxyprop-2-yl-alkyne or a protected alkyne can be directly synthesized using the commercially available 2-methyl-3-butyn-2-ol as an the alkyne source.[6] The protective group can be removed by heating the compound in a solution of potassium hydroxide in propan-2-ol (a retro-Favorskii reaction).[7]
See also
References
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
