1,4-Dichlorobenzene

1,4-Dichlorobenzene
1,4-Dichlorobenzene
1,4-Dichlorobenzene
Ball-and-stick model of 1,4-dichlorobenzene
Ball-and-stick model of 1,4-dichlorobenzene

1,4-dichlorobenzene crystallised on paper from DCM solution
Names
Preferred IUPAC name
1,4-Dichlorobenzene
Other names
1,4-DCB
para-Dichlorobenzene
p-Dichlorobenzene
p-DCB
PDCB
Paramoth
Para crystals
Paracide
Dichlorocide
Identifiers
3D model (JSmol)
1680023
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.003.092 Edit this at Wikidata
EC Number
  • 203-400-5
49722
KEGG
RTECS number
  • CZ4550000
UNII
UN number 3077
  • InChI=1S/C6H4Cl2/c7-5-1-2-6(8)4-3-5/h1-4H ☒N
    Key: OCJBOOLMMGQPQU-UHFFFAOYSA-N ☒N
  • ClC1=CC=C(Cl)C=C1
Properties
C6H4Cl2
Molar mass 147.00 g·mol−1
Appearance Colorless/white crystals[1]
Odor mothball-like[1]
Density 1.25 g/cm3, solid
Melting point 53.5 °C (128.3 °F; 326.6 K)
Boiling point 174 °C (345 °F; 447 K)
10.5 mg/100 mL (20 °C)
Vapor pressure 1.3 mmHg (20 °C)[1]
-82.93·10−6 cm3/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
 Suspected carcinogen
GHS labelling:
GHS07: Exclamation markGHS08: Health hazardGHS09: Environmental hazard
Warning
H302, H315, H317, H319, H332, H335, H351, H410
P201, P202, P261, P264, P270, P271, P272, P273, P280, P281, P301+P312, P302+P352, P304+P312, P304+P340, P305+P351+P338, P308+P313, P312, P321, P330, P332+P313, P333+P313, P337+P313, P362, P363, P391, P403+P233, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
2
0
Flash point 66 °C (151 °F; 339 K)
Explosive limits 2.5%-?[1]
Lethal dose or concentration (LD, LC):
500 mg/kg (rat, oral)
2950 mg/kg (mouse, oral)
2512 mg/kg (rat, oral)
2830 mg/kg (rabbit, oral)[2]
857 mg/kg (human, oral)
4000 mg/kg (rat, oral)
2800 mg/kg (guinea pig, oral)[2]
NIOSH (US health exposure limits):
PEL (Permissible)
 TWA 75 ppm (450 mg/m3)[1]
REL (Recommended)
 Ca[1]
IDLH (Immediate danger)
 Ca [150 ppm][1]
Related compounds
Related compounds
 1,2-Dichlorobenzene
1,3-Dichlorobenzene
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 ?)

1,4-Dichlorobenzene (1,4-DCB, p-DCB, or para-dichlorobenzene, sometimes abbreviated as PDCB or para) is an aryl chloride and isomer of dichlorobenzene with the formula C6H4Cl2. This colorless solid has a strong odor. The molecule consists of a benzene ring with two chlorine atoms (replacing hydrogen atoms) on opposing sites of the ring.

It is used as a disinfectant, pesticide, and deodorant, most familiarly in mothballs in which it is a replacement for the more traditional naphthalene because of naphthalene's greater flammability (though both chemicals have the same NFPA 704 rating). It is also used as a precursor in the production of the chemically and thermally resistant polymer poly(p-phenylene sulfide).[3]

  1. ^ a b c d e f g NIOSH Pocket Guide to Chemical Hazards. "#0190". National Institute for Occupational Safety and Health (NIOSH).
  2. ^ a b "p-Dichlorobenzene". National Institute for Occupational Safety and Health (NIOSH). 4 December 2014. Retrieved 6 March 2015.
  3. ^ Rossberg, M.; Lendle, W.; Pfleiderer, G.; Tögel, A.; Dreher, E. L.; Langer, E.; Rassaerts, H.; Kleinschmidt, P.; Strack, H.; Cook, R.; Beck, U.; Lipper, K.-A.; Torkelson, T.R.; Löser, E.; Beutel, K.K.; Mann, T. (2006). "Chlorinated Hydrocarbons". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a06_233.pub2. ISBN 978-3527306732.