Terphenyls

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The terphenyls form a group of substances that consist of a central benzene ring and two phenyl radicals connected to one another and thus of three phenyl rings. The different arrangement of the phenyl residues results in three constitutional isomers . As a commercially available product, terphenyl , it is a mixture of the three isomers.

Terphenyls
Surname o -terphenyl m -terphenyl p -terphenyl
other names 1,2-diphenylbenzene 1,3-diphenylbenzene 1,4-diphenylbenzene
Structural formula ortho-terphenyl meta-terphenyl para-terphenyl
CAS number 84-15-1 92-06-8 92-94-4
26140-60-3 (mixture of isomers)
PubChem 6766 7076 7115
Molecular formula C 18 H 14
Molar mass 230.31 g mol −1
Physical state firmly
Brief description white, flammable powder
Melting point 54-56 ° C 84-88 ° C 213 ° C
boiling point 332 ° C 379 ° C 404 ° C
density 1.14 g cm −3 1.23 g cm −3
solubility Practically insoluble in water
GHS
labeling
07 - Warning
Caution
07 - Warning 09 - Dangerous for the environment
Caution
07 - Warning 09 - Dangerous for the environment
Caution
H and P phrases 302 315-319-335-400 315-319-335-400
no EUH phrases
260-262 273-280-305 + 351 + 338-337 + 313-391 261-273-305 + 351 + 338
MAK Switzerland: 0.5 ml m −3 or 5 mg m −3
Toxicological data 1900 mg kg −1 ( LD 50 ,  rat ,  oral ) 2400 mg kg −1 ( LD 50 ,  rat ,  oral ) 500 mg kg −1 ( LD Lo ,  rat ,  oral )

use

The most widespread terphenyl is p -terphenyl, which is used as a dye (e.g. as a doping of terrylene ), as a laser material (e.g. for excimer lasers with a fluorescence maximum at 343 nm), as a scintillation counter and in sun creams. o -Terphenyl is used as a synthetic chemical. The polychlorinated terphenyls (PCT) derived from the terphenyls through Suzuki coupling have similar physical-chemical properties as the polychlorinated biphenyls (PCB) and were used, among other things, as heat exchangers and dielectrics in transformers .

Related links

Web links

Individual evidence

  1. ↑ a b c d e f Entry on o-terphenyl in the GESTIS substance database of the IFA , accessed on April 20, 2017(JavaScript required) .
  2. ↑ a b c data sheet m-terphenyl from Sigma-Aldrich , accessed on April 20, 2017 ( PDF ).
  3. ↑ a b c d e Entry on p-terphenyl in the GESTIS substance database of the IFA , accessed on April 20, 2017(JavaScript required) .
  4. ↑ Swiss Accident Insurance Fund (Suva): Limits - Current MAK and BAT values (search for 26140-60-3 ), accessed on December 8, 2019.
  5. ↑ Entry on m-terphenyl at TCI Europe, accessed on April 20, 2017.
  6. ↑ Entry on 1,1 ′: 4 ′, 1 ′ ′ - terphenyl in the ChemIDplus database of the United States National Library of Medicine (NLM), accessed on December 8, 2019.
  7. ↑ A. Pieper, H. Wichmann, M. Bahadir: Synthesis and behavior of polychlorinated terphenyls (PCT) under thermal stress ( Memento from September 26, 2016 in the Internet Archive )