Benzophenone


Benzophenone
Benzophenone
Identifiers
CAS number 119-61-9 YesY
PubChem 3102
ChemSpider 2991 YesY
UNII 701M4TTV9O YesY
DrugBank DB01878
KEGG C06354 YesY
ChEBI CHEBI:41308 YesY
ChEMBL CHEMBL90039 YesY
Jmol-3D images Image 1
Properties
Molecular formula C13H10O
Molar mass 182.217 g/mol
Appearance White solid
Density 1.11 g/cm3, solid
Melting point

47.9 °C

Boiling point

305.4 °C

Solubility in water Insoluble
Solubility Benzene, THF, ethanol, propylene glycol
Hazards
MSDS External MSDS by JT Baker
Main hazards Harmful (XN)
NFPA 704
NFPA 704.svg
1
3
0
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Benzophenone is the organic compound with the formula (C6H5)2CO, generally abbreviated Ph2CO. Benzophenone is a widely used building block in organic chemistry, being the parent diarylketone.

Contents

Uses

Benzophenone can be used as a photo initiator in UV-curing applications such as inks, imaging, and clear coatings in the printing industry. Benzophenone prevents ultraviolet (UV) light from damaging scents and colors in products such as perfumes and soaps. It can also be added to the plastic packaging as a UV blocker. Its use allows manufacturers to package the product in clear glass or plastic. Without it, opaque or dark packaging would be required.

In biological applications, benzophenones have been used extensively as photophysical probes to identify and map peptide–protein interactions[1] .

Synthesis

Benzophenone can be prepared by the reaction of benzene with carbon tetrachloride followed by hydrolysis of the resulting diphenyldichloromethane,[2] or by Friedel-Crafts acylation of benzene with benzoyl chloride in the presence of a Lewis acid (e.g. aluminium chloride) catalyst. The industrial synthesis relies on the copper-catalyzed oxidation of diphenylmethane with air.[3]

Organic chemistry

Benzophenone is a common photosensitizer in photochemistry. It crosses from the S1 state into the triplet state with nearly 100% yield. The resulting diradical will abstract a hydrogen atom from a suitable hydrogen donor to form a ketyl radical.

Benzophenone radical anion

Sodium reduces benzophenone to the deeply colored radical anion, diphenylketyl:

Na + Ph2CO → Na+Ph2CO·−

This ketyl is used in the purification of hydrocarbon solvents, because it reacts with water and oxygen to give non-volatile products.[4] The ketyl is soluble in the organic solvent being dried, so it reacts quickly with residual water and oxygen. In comparison, sodium is insoluble, and its heterogeneous reaction is much slower. The ketyl radical generally appears blue or purple, depending on the solvent.

Commercially significant derivatives

Substituted benzophenones such as oxybenzone and dioxybenzone are used in some sunscreens. The use of benzophenone-derivatives which structurally resemble a strong photosensitizer has been strongly criticized (see sunscreen controversy).[5]

p,p'-bis(N,N-dimethylamino)benzophenone or Michler's ketone has dimethylamino substituents at each para position.

The high-strength polymers PEEK, polyetherether ketones, are prepared from derivatives of benzophenone.

See also

References

  1. ^ Dorman, Gyorgy; Prestwich, Glenn D. (1 May 1994). "Benzophenone Photophores in Biochemistry". Biochemistry 33 (19): 5661–5673. doi:10.1021/bi00185a001. 
  2. ^ Marvel, C. S.; Sperry, W. M. (1941), "Benzophenone", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=cv1p0095 ; Coll. Vol. 1: 95 
  3. ^ Hardo Siegel, Manfred Eggersdorfer "Ketones" in Ullmann's Encyclopedia of Industrial Chemistry Wiley-VCH, 2002 by Wiley-VCH, Wienheim. DOI: 10.1002/14356007.a15_077
  4. ^ W. L. F. Armarego and C. Chai (2003). Purification of laboratory chemicals. Oxford: Butterworth-Heinemann. ISBN 0750675713. 
  5. ^ Knowland, John; McKenzie, Edward A.; McHugh, Peter J.; Cridland, Nigel A. (1993). "Sunlight-induced mutagenicity of a common sunscreen ingredient". FEBS Letters 324 (3): 309–313. doi:10.1016/0014-5793(93)80141-G. PMID 8405372. 

Notes

  • Merck Index, 11th edition, 1108.

Gallery


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Look at other dictionaries:

  • Benzophenone-n — Benzophenone, the base structure of these sunscreening agents Benzphenone 1 – benzophenone 12 (BP 1 –BP 12) are UVA/UVB absorbers. Most of them are used in sunscreens. Benzophenone 1 (2,4 dihydroxybenzophenone) Benzophenone 2 (2,2 ,4,4… …   Wikipedia

  • Benzophenone — Benzophénone Benzophénone Structure 2D de la benzophénone …   Wikipédia en Français

  • Benzophénone — Structure 2D de la benzophénone …   Wikipédia en Français

  • benzophénone — ● benzophénone nom féminin Cétone C6H5―CO―C6H5 obtenue par action du chlorure de benzoyle sur le benzène. benzophénone [bɛ̃zofenɔn] n. f. ÉTYM. 1849; de benzo , phén(yle), et one, suff. spécifique des cétones. → Acétophénone. ❖ ♦ Chim. Cétone… …   Encyclopédie Universelle

  • benzophenone — [ben΄zō fi nōn′, ben΄zōfē′nōn΄] n. [ BENZO + PHEN(OL) + ONE] a white, sweet smelling crystalline ketone, C6H5COC6H5, used as an intermediate compound in making flavorings, fragrances, etc …   English World dictionary

  • benzophenone — noun Etymology: International Scientific Vocabulary benz + phen + one Date: 1877 a colorless crystalline ketone C13H10O used especially as a perfume fixative and in sunscreens; also a derivative of benzophenone …   New Collegiate Dictionary

  • benzophenone — ben·zo·phe·none .ben zō fi nōn, fē .nōn n a colorless crystalline ketone C13H10O used chiefly in perfumery and sunscreens also a derivative of benzophenone * * * ben·zo·phen·one (ben″zo fenґōn) an aromatic ketone that is a component of …   Medical dictionary

  • benzophenone — benzfenonas statusas T sritis chemija formulė (C₆H₅)₂CO atitikmenys: angl. benzophenone rus. бензофенон ryšiai: sinonimas – difenilketonas …   Chemijos terminų aiškinamasis žodynas

  • benzophenone — /ben zoh fi nohn , fee nohn/, n. Chem. a crystalline, water insoluble ketone, C13H10O, used in organic synthesis. Also called diphenyl ketone. [1880 85; BENZO + PHEN + ONE] * * * …   Universalium

  • benzophenone — noun a) Any of a class of aromatic ketones based on the parent compound diphenylketone (CH)CO; used, amongst other things, as ingredients in sunblock. b) The compound diphenylmethanone …   Wiktionary


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