Benzocyclobutene

Benzocyclobutene
Skeletal formula
Ball-and-stick model
Names
Preferred IUPAC name
Bicyclo[4.2.0]octa-1,3,5-triene
Other names
Benzocyclobutane
BCB
Benzocyclobutene (not in accordance with IUPAC nomenclature)
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.161.355 Edit this at Wikidata
UNII
  • InChI=1S/C8H8/c1-2-4-8-6-5-7(8)3-1/h1-4H,5-6H2 ☒N
    Key: UMIVXZPTRXBADB-UHFFFAOYSA-N ☒N
  • InChI=1/C8H8/c1-2-4-8-6-5-7(8)3-1/h1-4H,5-6H2
    Key: UMIVXZPTRXBADB-UHFFFAOYAR
  • C12=CC=CC=C1CC2
Properties
C8H8
Molar mass 104.152 g·mol−1
Density 0.957 g/cm3
Boiling point 150 °C (302 °F; 423 K)
1.541
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Benzocyclobutene (BCB) is a benzene ring fused to a cyclobutane ring. It has chemical formula C8H8.[1]

BCB is frequently used to create photosensitive polymers. BCB-based polymer dielectrics may be spun on or applied to various substrates for use in Micro Electro-Mechanical Systems (MEMS) and microelectronics processing. Applications include wafer bonding, optical interconnects, low-κ dielectrics, or even intracortical neural implants.

Reactions

Benzocyclobutene is a strained system which, upon heating to approximately 180 °C, causes the cyclobutene to undergo a conrotatory ring-opening reaction, forming o-xylylene. Since this process destroys the aromaticity of the benzene ring, the reverse reaction is highly favored.

Thermal generation of o-xylylene from benzocyclobutene
Thermal generation of o-xylylene from benzocyclobutene

o-Xylylenes generated in this way have been used prolifically in cycloaddition reactions, which restore the aromaticity to the benzene ring, while forming a new annulated species.[2]

Uses

The benzocyclobutene moiety has also appeared in a number of chemical compounds with pharmacological properties such as ivabradine and S33005. Additionally, the benzocyclobutene analog of 2C-B has been prepared[3] and a benzocyclobutene-derived amphetamine has been patented.[4]

See also

References

  1. ^ 164410 Benzocyclobutene 98%
  2. ^ Mehta, G.; Kotha, S. (2001). "Recent chemistry of benzocyclobutenes" (PDF). Tetrahedron Lett. 57 (4): 625–659. doi:10.1016/s0040-4020(00)00958-3.
  3. ^ "The Binding Database".
  4. ^ US 3149159, "Substituted 7-aminoalkylbicyclo-[4. 2. 0]octa-1,3,5-trienes"