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Benzal chloride

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Benzal chloride
Skeletal formula of benzal chloride
Skeletal formula of benzal chloride
Ball-and-stick model of benzal chloride
Ball-and-stick model of benzal chloride
Names
Preferred IUPAC name
(Dichloromethyl)benzene
Other names
  • Benzyl dichloride
  • Benzylidene chloride
  • α,α-Dichlorotoluene
  • PhCl2H
Identifiers
3D model (JSmol)
1099407
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.002.463 Edit this at Wikidata
EC Number
  • 249-854-8
KEGG
MeSH Compounds Benzylidene Compounds
RTECS number
  • CZ5075000
UNII
UN number 1886 2810
  • InChI=1S/C7H6Cl2/c8-7(9)6-4-2-1-3-5-6/h1-5,7H checkY
    Key: CAHQGWAXKLQREW-UHFFFAOYSA-N checkY
  • ClC(Cl)c1ccccc1
  • C1=CC=C(C=C1)C(Cl)Cl
Properties
C7H6Cl2
Molar mass 161.03 g/mol
Appearance Colorless liquid
Density 1.254 g/cm3, liquid
Melting point −17 to −15 °C (1 to 5 °F; 256 to 258 K)
Boiling point 205 °C (401 °F; 478 K) (82 °C at 10 mmHg)
0.25 g/L at 39 °C
Vapor pressure 0.6 kPa (45 °C)
Hazards
GHS labelling:
GHS03: OxidizingGHS06: ToxicGHS07: Exclamation markGHS08: Health hazard
Danger
H302, H315, H318, H331, H335, H351
P201, P202, P261, P264, P270, P271, P280, P281, P301+P312, P302+P352, P304+P340, P305+P351+P338, P308+P313, P310, P311, P312, P321, P330, P332+P313, P362, P403+P233, P405, P501
Flash point 93 °C (199 °F; 366 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

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. ^ Lipper, Karl-August; Löser, Eckhard (2011). "Benzyl Chloride and Other Side-Chain Chlorinated Aromatic Hydrocarbons". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.o04_o01. ISBN 978-3527306732.