2,2,4,4-Tetramethylcyclobutanedione is the

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...

with the formula (CH₃)₄C₄O₂. The compound is a

diketone In organic chemistry, a dicarbonyl is a molecule containing two carbonyl () groups. Although this term could refer to any organic compound containing two carbonyl groups, it is used more specifically to describe molecules in which both carbonyls ...

of cyclobutane, bearing four

methyl group In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula . In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many ...

s. It is a white solid that is used as a precursor to diverse industrial products.

Synthesis and reactions

2,2,4,4-Tetramethylcyclobutanedione is the head-to-tail dimer of dimethyl

ketene In organic chemistry, a ketene is an organic compound of the form , where R and R' are two arbitrary monovalent chemical groups (or two separate substitution sites in the same molecule). The name may also refer to the specific compound etheno ...

. It arises spontaneously when dimethylketene is produced by dehydrohalogenation of

isobutyryl chloride Isobutyryl chloride (2-methylpropanoyl chloride) is the simplest branched-chain acyl chloride. It is found at room temperature as a corrosive, colorless liquid. References Acyl chlorides Reagents for organic chemistry {{Organic-compoun ...

with triethylamine. The 2,2,4,4-tetramethylcyclobutanedione isomerizes to the lactone called dimethylketene dimer (4-isopropylidene-3,3-dimethyl-2-oxetanone). Dimethylketene dimer is a precursor to various

alkyl ketene dimer Alkyl ketene dimers (AKDs) are a family of organic compounds based on the 4-membered ring system of oxetan-2-one, which is also the central structural element of propiolactone and diketene. Attached to the oxetane ring of technically relevant alk ...

s, which are used in papermaking.

Hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a Catalysis, catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or S ...

of 2,2,4,4-tetramethylcyclobutanedione gives 2,2,4,4-tetramethylcyclobutanediol, which is of interest in polymer chemistry.

References

{{DEFAULTSORT:Tetramethylcyclobutanedione, 2,2,4,4- Diketones Cyclic ketones