Benzocyclobutene

Benzocyclobutene
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
CAS Number	694-87-1 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:87328 ;
ChemSpider	62868 ;
ECHA InfoCard	100.161.355
PubChem CID	69667;
UNII	MF7U8F3YLB ;
CompTox Dashboard (EPA)	DTXSID3073927 ;
	InChI InChI=1S/C8H8/c1-2-4-8-6-5-7(8)3-1/h1-4H,5-6H2 Key: UMIVXZPTRXBADB-UHFFFAOYSA-N ; InChI=1/C8H8/c1-2-4-8-6-5-7(8)3-1/h1-4H,5-6H2 Key: UMIVXZPTRXBADB-UHFFFAOYAR;
	SMILES C12=CC=CC=C1CC2;
Properties
Chemical formula	C8H8
Molar mass	104.152 g·mol−1
Density	0.957 g/cm3
Boiling point	150 °C (302 °F; 423 K)
Refractive index (nD)	1.541
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

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

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]

References

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

[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"

[1]

[2]

[3]

[4]

Benzocyclobutene

Contents

Reactions

Uses

See also

References

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
CAS Number	694-87-1^Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:87328^N
ChemSpider	62868^N
ECHA InfoCard	100.161.355
PubChem CID	69667
UNII	MF7U8F3YLB^Y
CompTox Dashboard (EPA)	DTXSID3073927
InChI 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
SMILES C12=CC=CC=C1CC2
Properties
Chemical formula	C₈H₈
Molar mass	104.152 g·mol⁻¹
Density	0.957 g/cm³
Boiling point	150 °C (302 °F; 423 K)
Refractive index (n_D)	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 ^YN ?) Infobox references