1,3-Cyclobutanedione

1,3-Cyclobutanedione
Names
Preferred IUPAC name
Cyclobutane-1,3-dione
Identifiers
3D model (JSmol)
ChemSpider
  • 1,3-cyclobutanedione tautomer: 25456
  • 3-hydroxycyclobut-2-enone: 10004000
  • 1,3-cyclobutanedione tautomer: 27357
  • 3-hydroxycyclobut-2-enone: 11829353
  • InChI=1S/C4H4O2/c5-3-1-4(6)2-3/h1-2H2
    Key: PZQGSZRQKQZCOJ-UHFFFAOYSA-N
  • 3-hydroxycyclobut-2-enone: InChI=1S/C4H4O2/c5-3-1-4(6)2-3/h1,5H,2H2
    Key: IHXWECHPYNPJRR-UHFFFAOYSA-N
  • 1,3-cyclobutanedione tautomer: C1C(=O)CC1=O
  • 3-hydroxycyclobut-2-enone: C1C(=CC1=O)O
Properties
C4H4O2
Molar mass 84.074 g·mol−1
Appearance colorless or white solid
Density 1.12 g/cm3
Melting point 119–120 °C (246–248 °F; 392–393 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

1,3-Cyclobutanedione is an organic compound with the formula (CH2)2(CO)2. It is an isomer of 1,2-cyclobutanedione. The compound would be of little interest except that its tautomer is a subunit in some commercial dyes.

In solution, 1,3-cyclobutanedione exists in equilibrium with a less stable tautomer, called squaraine, 3-hydroxycyclobut-2-enone. Squaraine dyes are, formally at least, derivatives of squaraine. In such dyes, the ene-one tautomer predominates.

The mixture of tautomers can be prepared by hydrolysis of 1-ethoxycyclobutene-3-one, which is prepared from the cycloaddition of ethoxyacetylene to ketene.

This article is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.