2,2,4,4-Tetramethylcyclobutanedione

2,2,4,4-Tetramethylcyclobutanedione is the organic compound with the formula (CH3)4C4O2. The compound is a diketone of cyclobutane, bearing four methyl groups. It is a white solid that is used as a precursor to diverse industrial products.

2,2,4,4-Tetramethylcyclobutanedione
Names
Preferred IUPAC name
2,2,4,4-Tetramethylcyclobutane-1,3-dione
Other names
Tetramethyl-1,3-cyclobutanedione, Tetramethylcyclobuta-1,3-dione
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.012.063
EC Number
  • 213-269-6
UNII
Properties
C8H12O2
Molar mass 140.182 g·mol−1
Appearance Colorless or white solid
Melting point 112–115 °C (234–239 °F; 385–388 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Synthesis and reactions

2,2,4,4-Tetramethylcyclobutanedione is the head-to-tail dimer of dimethylketene. It arises spontaneously when dimethylketene is produced by dehydrohalogenation of isobutyryl chloride with triethylamine.[1]

The 2,2,4,4-tetramethylcyclobutanedione isomerizes to the lactone called dimethylketene dimer (4-isopropylidene-3,3-dimethyl-2-oxetanone).[2] Dimethylketene dimer is a precursor to various alkyl ketene dimers, which are used in papermaking.

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

References
  1. R. Huisgen, P. Otto (1968), "The mechanism of dimerization of dimethylketene", J. Am. Chem. Soc., 90 (19), pp. 5342–5343, doi:10.1021/ja01021a090
  2. R.H. Hasek; R.D. Clark; G.L. Mayberry (1968). "Dimethylketene β-Lactone Dimer". Organic Syntheses. 48: 72. doi:10.15227/orgsyn.048.0072.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.