Nelumbo

by | Mar 19, 2018 | Nelumbo

How Can We Help?
You are here:
< Back

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]

Synthesis and reactions

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

  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.
Categories
Table of Contents