Benzal chloride

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Benzal chloride
Skeletal formula of benzal chloride Ball-and-stick model of benzal chloride
Identifiers
CAS number 98-87-3 N
PubChem 7411
ChemSpider 13882337 YesY
UNII 222447TR16 N
EC number 249-854-8
UN number 1886
KEGG C19165 YesY
MeSH Compounds Benzylidene Compounds
RTECS number CZ5075000
Beilstein Reference 1099407
Jmol-3D images Image 1
Properties
Molecular formula C7H6Cl2
Molar mass 161.03 g/mol
Appearance Colorless liquid
Density 1.254 g/cm3, liquid
Melting point −17 to −15 °C
Boiling point 205 °C (82 °C @10 mm Hg)
Solubility in water 0.25 g/L at 39 °C
Vapor pressure 0.6 kPa (45 °C)
Hazards
EU classification Toxic (T), Carc. Cat. 2B, Dangerous for the environment (N)
R-phrases 22-23-37/38-40-41
S-phrases 36/37-38-45
Flash point 93 °C (199 °F; 366 K)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
Infobox references

Benzal chloride is an organic compound with the formula C6H5CHCl2.[1] This colourless liquid is a lachrymator and is used as a building block in organic synthesis.

Preparation and usage[edit]

Benzal chloride is produced by the free radical chlorination of toluene, being preceded in the process by benzyl chloride (C6H5CH2Cl) and followed by benzotrichloride (C6H5CCl3):

C6H5CH3 + Cl2 → C6H5CH2Cl + HCl
C6H5CH2Cl + Cl2 → C6H5CHCl2 + HCl
C6H5CHCl2 + Cl2 → C6H5CCl3 + HCl

Benzylic halides are typically strong alkylating agents, and for this reason benzal chloride is treated as a hazardous compound.

Treatment of benzal chloride with sodium gives stilbene.

Most benzal chloride main industrial use is as a precursor to benzaldehyde. This conversion involves hydrolysis in the presence of base:[2]

C6H5CHCl2 + H2O → C6H5CHO + 2 HCl

References[edit]

  1. ^ "BENZAL CHLORIDE". International Programme on Chemical Safety. Retrieved 2007-10-30. 
  2. ^ Karl-August Lipper and Eckhard Löser “Benzyl Chloride and Other Side-Chain Chlorinated Aromatic Hydrocarbons" in Ullmann’s Encyclopedia of Industrial Chemistry, 2011, Wiley-VCH, Weinheim. doi:10.1002/14356007.o04_o01