Terthiophene

Terthiophene

Names
IUPAC name 2,2':5',2"-terthiophene
Other names α-Terthienyl 2,5-Di(2-thienyl)thiophene
Identifiers
CAS Number	1081-34-1
ChEBI	CHEBI:10335
ChEMBL	ChEMBL90017
ChemSpider	58578
Jmol interactive 3D	Image
PubChem	65067
RTECS number	WZ9717750
InChI InChI=1S/C12H8S3/c1-3-9(13-7-1)11-5-6-12(15-11)10-4-2-8-14-10/h1-8H Key: KXSFECAJUBPPFE-UHFFFAOYSA-N InChI=1/C12H8S3/c1-3-9(13-7-1)11-5-6-12(15-11)10-4-2-8-14-10/h1-8H Key: KXSFECAJUBPPFE-UHFFFAOYAI
SMILES s1cccc1c2sc(cc2)c3sccc3
Properties
Chemical formula	C12H8S3
Molar mass	248.39 g/mol
Appearance	pale yellow solid
Melting point	93-95 °C
Solubility in water	insoluble
Hazards
Main hazards	flammable
S-phrases	S22 S24/25
Related compounds
Related compounds	Thiophene polythiophene
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Terthiophene is the organic compound with the formula [C₄H₃S]₂C₄H₂S. It is an oligomer of the heterocycle thiophene, a shorter oligomer is dithienyl, and the parent polymer is polythiophene. In the most common isomer of terthiophene, two thienyl groups are connected via their 2 positions to a central thiophene, also at the carbon atoms flanking the sulfur.

Preparation of terthiophene

Terthiophene is prepared by the nickel- or palladium-catalysed coupling reaction of 2,5-dibromothiophene with the Grignard reagent derived from 2-bromothiophene.^[1]

Properties and applications

This isomer is a pigment in African marigolds (Tagetes spp.) and exhibits some biological activity because it sensitizes the formation of singlet oxygen.^[2] It is responsible for the insecticidal activity of Tagetes minuta.^[3]

Various substituted terthiophenes occur naturally, including 5,5''-dichloro-α-terthiophene, 5-chloro-α-terthiophene, 5-acetyl α-terthiophene, and 5-carboxyl bithiophene.^[4]

Terthiophene has been employed as building block for the organic semi-conductor polythiophene.

See also

• Biphenyl
• Terphenyl
• Terpyridine
• Naphthalene, having fused rings.

References

1. Smeets, B. J. J.; Meijer, R. H.; Meuldijk, J.; Vekemans, J. A. J. M.; Hulshof, L. A. (2003). "Process Design and Scale-Up of the Synthesis of 2,2':5',2"-Terthienyl". Organic Process Research & Development 7 (1): 10–16. doi:10.1021/op020044n.
2. Ciofalo, M.; Ponterini, G. (1994). "Generation of singlet oxygen by 2,2':5',2"-terthiophene and some of its derivatives". Journal of Photochemistry and Photobiology A 83 (1): 1–6. doi:10.1016/1010-6030(94)03802-3. ISSN 1010-6030. CODEN: JPPCEJ.
3. Perich, M. J.; Wells, C.; Bertsch, W.; Tredway, K. E. (1995). "Isolation of the insecticidal components of Tagetes minuta (Compositae) against mosquito larvae and adults". Journal of the American Mosquito Control Association 11 (3): 307–310. PMID 8551298.
4. Liu, Y.; Ye, M.; Guo, H. Z.; Zhao, Y. Y.; Guo, D. A. (2002). "New thiophenes from Echinops grijisii". Journal of Asian Natural Products Research 4 (3): 175–178. doi:10.1080/1028602021000000071. ISSN 1028-6020. PMID 12118504. CODEN: JANRFI.