Benzoin (organic compound)

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Benzoin
Names
Preferred IUPAC name
2-Hydroxy-1,2-diphenylethan-1-one
Other names
2-Hydroxy-2-phenylacetophenone
2-Hydroxy-1,2-diphenylethanone
Desyl alcohol
Bitter almond oil camphor
Identifiers
3D model (
JSmol
)
3DMet
391839
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard
100.003.938 Edit this at Wikidata
KEGG
RTECS number
  • DI1590000
UNII
  • InChI=1S/C14H12O2/c15-13(11-7-3-1-4-8-11)14(16)12-9-5-2-6-10-12/h1-10,13,15H checkY
    Key: ISAOCJYIOMOJEB-UHFFFAOYSA-N checkY
  • InChI=1/C14H12O2/c15-13(11-7-3-1-4-8-11)14(16)12-9-5-2-6-10-12/h1-10,13,15H
    Key: ISAOCJYIOMOJEB-UHFFFAOYAO
  • O=C(c1ccccc1)C(O)c2ccccc2
  • c1ccc(cc1)C(C(=O)c2ccccc2)O
Properties
C14H12O2
Molar mass 212.248 g·mol−1
Appearance Off-white crystals
Density 1.310 g/cm3 (20 °C)[1]
Melting point 135 to 139[1] °C (275 to 282 °F; 408 to 412 K)
Boiling point 330 to 356[1] °C (626 to 673 °F; 603 to 629 K)
Slightly soluble
Solubility in ethanol Very good[1]
Solubility in ether Slightly soluble
Solubility in chlorine Soluble
Solubility in chloroform Very good[1]
Hazards
GHS labelling:
H412
P273, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
1
1
0
Lethal dose or concentration (LD, LC):
10.000 mg/kg
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Benzoin (

phenyl groups. It appears as off-white crystals, with a light camphor-like odor. Benzoin is synthesized from benzaldehyde in the benzoin condensation
. It is chiral and it exists as a pair of enantiomers: (R)-benzoin and (S)-benzoin.

Benzoin is not a constituent of

benzoin resin obtained from the benzoin tree (Styrax) or tincture of benzoin. The main component in these natural products is benzoic acid
.

History

Benzoin was first reported in 1832 by

hydrocyanic acid.[2] The catalytic synthesis by the benzoin condensation was improved by Nikolay Zinin during his time with Liebig.[3][4]

Uses

The main use of benzoin is as a precursor to

Benzoin also sees wide spread use in powder coating formulations, where it acts as a degassing agent during the curing stage. This action prevents surface defects such as 'pinholing'.[9][10]

Benzoin can be used in the preparation of several pharmaceutical drugs including oxaprozin, ditazole, and phenytoin.[11]

Preparation

Benzoin is prepared from benzaldehyde via the benzoin condensation.[12]

References

External links

  • Benzoin synthesis, Organic Syntheses, Coll. Vol. 1, p. 94 (1941); Vol. 1, p. 33 (1921)