Dibenzothiophene (DBT, diphenylene sulfide) is the organosulfur compound consisting of two benzene rings fused to a central thiophene ring. It has the chemical formula C12H8S. It is a colourless solid that is chemically somewhat similar to anthracene. This tricyclic heterocycle, and especially its disubstituted derivative 4,6-dimethyldibenzothiophene are problematic impurities in petroleum.[1]

Dibenzothiophene
Skeletal formula of dibenzothiophene
Ball-and-stick model of the dibenzothiophene molecule
Sample
Names
Preferred IUPAC name
Dibenzo[b,d]thiophene
Other names
Diphenylene sulfide, DBT
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.004.613 Edit this at Wikidata
EC Number
  • 205-072-9
KEGG
RTECS number
  • HQ3490550
UNII
  • InChI=1S/C12H8S/c1-3-7-11-9(5-1)10-6-2-4-8-12(10)13-11/h1-8H checkY
    Key: IYYZUPMFVPLQIF-UHFFFAOYSA-N checkY
  • InChI=1/C12H8S/c1-3-7-11-9(5-1)10-6-2-4-8-12(10)13-11/h1-8H
    Key: IYYZUPMFVPLQIF-UHFFFAOYAY
  • c1ccc2c(c1)c3ccccc3s2
Properties
C12H8S
Molar mass 184.26 g/mol
Appearance Colourless crystals
Density 1.252 g/cm3
Melting point 97 to 100 °C (207 to 212 °F; 370 to 373 K) (lit.)
Boiling point 332 to 333 °C (630 to 631 °F; 605 to 606 K)
insol.
Solubility in other solvents benzene and related
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
flammable, toxic
GHS labelling:
GHS06: ToxicGHS07: Exclamation markGHS09: Environmental hazard
Danger
H301, H302, H311, H315, H331, H332, H410
P261, P264, P270, P271, P273, P280, P301+P312, P302+P352, P304+P312, P304+P340, P311, P312, P321, P322, P330, P332+P313, P361, P362, P363, P391, P403+P233, P405, P501
Related compounds
Related compounds
Thiophene
Anthracene
Benzothiophene
Dibenzofuran
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Synthesis and reactions

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Dibenzothiophene is prepared by the reaction of biphenyl with sulfur dichloride in the presence of aluminium chloride.[2]

Reduction with lithium results in scission of one C-S bond. With butyllithium, this heterocycle undergoes stepwise lithiation at the 4-position. S-oxidation with peroxides gives the sulfoxide.[3]

Dibenzothiophene is electron-rich, and naturally undergoes aromatic substitution para to the sulfide. Oxidation to the sulfoxide or sulfone leaves the compound electron poor, and substitution occurs at the meta position instead.[4]

References

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  1. ^ Ho, Teh C. (2004). "Deep HDS of Diesel Fuel: Chemistry and Catalysis". Catalysis Today. 98 (1–2): 3–18. doi:10.1016/j.cattod.2004.07.048.
  2. ^ Klemm, L. H.; Karchesy, Joseph J. (1978). "The Insertion and Extrusion of Heterosulfur Bridges. VIII. Dibenzothiophene from Biphenyl and Derivatives". Journal of Heterocyclic Chemistry. 15 (4): 561–563. doi:10.1002/jhet.5570150407.
  3. ^ Waldecker, Bernd; Kafuta, Kevin; Alcarazo, Manuel (2019). "Preparation of 5-(Triisopropylalkynyl) dibenzo[b,d]thiophenium triflate". Organic Syntheses. 96: 258–276. doi:10.15227/orgsyn.096.0258. S2CID 239319277.
  4. ^ Bhanuchandra, M.; Yorimitsu Hideki. "Dibenzothiophene 5,5-dioxide". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rn02046.