Chemical Properties
clear colorless to slightly yellow viscous liquid
Uses
1-Acetoxy-1,3-butadiene was used as diene in the following reactions:
- Diels-Alder reaction with ortho-carbazolequinones to yield benzocarbazolequinone.
- Diels-Alder reaction with diethyl ketovinylphosphonate, with and without Lewis acid assistance.
- Diels-Alder reaction with methyl acrylate to yield racemic forms of 2-hydroxy-3-cyclohexenecarboxylic acid.
It was used for the reaction with dienophiles such as maleimides, a juglone, a butyne-1,4-dione and methyl 2-(4-methylphenyl)-2
H-azirine-3-carboxylate and during visible light photocatalysis. It was also used as reactant during intermolecular oxa-Pictet-Spengler cyclization.
General Description
1-Acetoxy-1,3-butadiene (1-ABD) can be generated by potassium or sodium acetate catalyzed reaction between crotonaldehyde and acetic anhydride. The product is a mixture of
cis and
trans forms, that has been confirmed by its physical properties and IR spectra. It is reported to be formed as a major product during the acetoxylation of 1,3-butadiene (BD) in gas-phase in the presence of Pd-KOAc (palladium-potassium acetate) catalyst. 1-ABD participates as 2Π or 4Π diene in cycloaddition reactions. Enantioselective Diels Alder reaction of 2-methoxy-5-methyl-1,4-benzoquinone with 1-ABD in the presence of molecular sieves (mesh size:4?) has been reported.
Safety Profile
Poison by inhalation. Moderatelytoxic by other routes. A skin irritant. Mutation datareported. When heated to decomposition it emits acridsmoke.
Purification Methods
The commercial sample is stabilised with 0.1% of p-tert-butylcatechol. If the material contains crotonaldehyde (by IR, used in its synthesis), it should be dissolved in Et2O, shaken with 40% aqueous sodium bisulfite, then 5% aqueous Na2CO3, water, dried (Na2SO4) and distilled several times in a vacuum through a Widmer [Helv Chim Acta 7 59 1924] (p 11) or Vigreux column (p 11) [Wicterle & Hudlicky Collect Czech Chem Commun 12 564 1947, Hagemeyer & Hull Ind Eng Chem 41 2920 1949]. [Beilstein 2 III 295.]
