| Identification | More | [Name]
Naphthalene | [CAS]
91-20-3 | [Synonyms]
Naftalen
whitetar
mothballs
NAPTHALIN
NAPHTHENE
mighty150
mightyrd1
White tar
Moth balls
camphortar
Mighty 150
Mighty rd1
NAPHTHALIN
Albocarbon
NAPTHALENE
mothflakes
naphtalene
NCI-C52904
Naphthaline
TAR CAMPHOR
Camphor tar
NAPHTHALENE
Dezodorator
Moth flakes
'LGC' (2402)
'LGC' (2603)
JACS-91-20-3
1-NAPHTHALENE
Naphthalene.6
Naphthalene>
NAPHTHALENE 99%
Naphthalene,98%
Naphthaleneball
naftalen(polish)
NAPTHALENE CRUDE
Naphthalene,99+%
Naphthalene,99.6%
CRUDE NAPHTHALENE
naphthalene, pure
naphthalene,crude
Napthalene, molten
Naphthalene, 99.5%
NAPHTHALENE FLAKES
rcrawastenumberu165
Naphthalene, refined
Naphthalin
Naphthene
NAPHTHALENE GR 99.5%
Naphthalene Standard
Naphthalene (200 mg)
naphthalene solution
Naphthalene, molten.
Naphthalene, 99% 250GR
NapthaleneForSynthesis
Rcra waste number U165
NAPHTHALENE WHITE, PURE
naphthalene naphthalene
REFINED NAPTHALENE POWDER
Naphthalene Zone Refined
REFINED NAPHTALENE POWDER
Naphthalene 5g [91-20-3]
NAPHTHALENE, 5000MG, NEAT
Naphthalene Odor Standard
NAPHTHALENE, 99% PURIFIED
Naphthalene, reagent grade
Faulding Naphthalene Flakes
Naphthalene, synthesis grade
NAPTHALENE FLAKES. (REFINED)
NAPTHALENE CRUDE GREY FLAKES
Naphthalene,ScintillationGrade
NAPHTHALENE, FOR SCINTILLATION
NaphthaleneSolution,10mg/L,1ml
NaphthaleneSolution,50mg/L,1ml
NAPHTHALENE FOR SYNTHESIS 1 KG
Naphthalene ISO 9001：2015 REACH
NaphthaleneSolution,200mg/L,1ml
NaphthaleneSolution,100mg/L,1ml
NaphthaleneSolution,250mg/L,1ml
NaphthaleneSolution,500mg/L,1ml
Naphthalene (grade unspecified)
NaphthaleneSolution,5,000mg/L,1ml
NaphthaleneSolution,2,000mg/L,1ml
NaphthaleneSolution,1,000mg/L,1ml
Melting point standard 79-81.C
Melting point standard naphthalene
NAPHTHALENE, 1X1ML, MEOH, 200UG/ML
NapthalenePurissScintillationGrade
NAPHTHALENE,RECRYSTALLIZED,REAGENT
NaphthaleneSolution,5,000mg/L,2x5ml
NAPHTHALENE, 1X1ML, MEOH, 5000UG/ML
NAPHTHALENE, 99+%, SCINTILLATION GRADE
Naphthalene, scintillation grade, 99+%
Naphthalene solution standard material
Naphthalene, scintillation grade, 99+% 5GR
Naphthalene, scintillation grade, 99+% 250GR
NaphthaleneZoneRefined(numberofpasses:23)>
Naphthalene suitable for scintillation, >=99%
Naphthalene Zone Refined (number of passes:23)
Naphthalene (1mg/ml in Methanol) [for Water Analysis]
NAPHTHALENE, 99%, PURIFIEDNAPHTHALENE, 99%, PURIFIEDNAPHTHALENE, 99%, PURIFIEDNAPHTHALENE, 99%, PURIFIED | [EINECS(EC#)]
202-049-5 | [Molecular Formula]
C10H8 | [MDL Number]
MFCD00001742 | [Molecular Weight]
128.17 | [MOL File]
91-20-3.mol |
| Chemical Properties | Back Directory | [Description]
Naphthalene occurs as transparent prismatic plates also available as white scales, powder
balls, or cakes with a characteristic mothball or strong coal tar and aromatic odour. It is
sparingly soluble in water but soluble in methanol/ethanol and very soluble in ether.
Naphthalene is a commercially important aromatic hydrocarbon. Naphthalene occurs as
a white solid or powder. Naphthalene occurs in coal tar in large quantities and is easily
isolated from this source in pure condition. It volatilises and sublimes at room temperature
above the melting point. The primary use for naphthalene is in the production of
phthalic anhydride, also of carbamate insecticides, surface active agents and resins, as a
dye intermediate, as a synthetic tanning agent, as a moth repellent, and in miscellaneous
organic chemicals. Naphthalene is used in the production of phthalic anhydride; it is also
used in mothballs. Naphthalene is also used in the manufacture of phthalic and anthranilic
acids to make indigo, indanthrene, and triphenyl methane dyes, for synthetic resins,
lubricant, celluloid, lampblack, smokeless powder, and hydronaphthalenes. Naphthalene
is also used in dusting powders, lavatory deodorant discs, wood preservatives, fungicide,
and as an insecticide. It has been used as an intestinal antiseptic and vermicide and in
the treatment of pediculosis and scabies. | [Appearance]
Naphthalene is a colorless to brown crystalline
solid with a characteristic “moth ball” odor. Shipped
as a molten solid. | [Melting point ]
80-82 °C (lit.) | [Boiling point ]
218 °C (lit.) | [density ]
0.99
| [vapor density ]
4.4 (vs air)
| [vapor pressure ]
0.03 mm Hg ( 25 °C)
| [refractive index ]
1.5821 | [Fp ]
174 °F
| [storage temp. ]
APPROX 4°C
| [solubility ]
methanol: soluble50mg/mL, clear, colorless | [form ]
Faint beige to brown to salmon red powder | [color ]
White to almost white | [Specific Gravity]
1.145 | [Odor]
at 10.00 % in benzyl benzoate. pungent dry tarry | [explosive limit]
0.9-5.9%(V) | [Odor Type]
pungent | [Water Solubility ]
30 mg/L (25 ºC) | [Merck ]
14,6370 | [BRN ]
1421310 | [Henry's Law Constant]
5.64 at 25 °C (thermodynamic method-GC/UV spectrophotometry, Altschuh et al., 1999) | [Dielectric constant]
2.5（85℃） | [Exposure limits]
TLV-TWA 10 ppm （～50 mg/m3) (ACGIH,
MSHA, and OSHA); STEL 15 ppm
(～75 mg/m3) (ACGIH); IDLH 500 ppm. | [InChIKey]
UFWIBTONFRDIAS-UHFFFAOYSA-N | [LogP]
3.7 at 25℃ | [CAS DataBase Reference]
91-20-3(CAS DataBase Reference) | [IARC]
2B (Vol. 82) 2002 | [NIST Chemistry Reference]
Naphthalene(91-20-3) | [EPA Substance Registry System]
91-20-3(EPA Substance) |
| Safety Data | Back Directory | [Hazard Codes ]
Xn,N,F,T | [Risk Statements ]
R22:Harmful if swallowed.
R40:Limited evidence of a carcinogenic effect.
R50/53:Very Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment .
R67:Vapors may cause drowsiness and dizziness.
R65:Harmful: May cause lung damage if swallowed.
R38:Irritating to the skin.
R11:Highly Flammable.
R39/23/24/25:Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed .
R23/24/25:Toxic by inhalation, in contact with skin and if swallowed .
R52/53:Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment . | [Safety Statements ]
S36/37:Wear suitable protective clothing and gloves .
S46:If swallowed, seek medical advice immediately and show this container or label .
S60:This material and/or its container must be disposed of as hazardous waste .
S61:Avoid release to the environment. Refer to special instructions safety data sheet .
S62:If swallowed, do not induce vomiting: seek medical advice immediately and show this container or label .
S45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) .
S16:Keep away from sources of ignition-No smoking .
S7:Keep container tightly closed . | [RIDADR ]
UN 1334 4.1/PG 3
| [WGK Germany ]
3
| [RTECS ]
QJ0525000
| [Autoignition Temperature]
978 °F | [TSCA ]
Yes | [HazardClass ]
4.1 | [PackingGroup ]
III | [HS Code ]
29029010 | [Safety Profile]
Human poison by
ingestion. Experimental poison by ingestion, intravenous, and intraperitoneal routes.
Moderately toxic by subcutaneous route. An
experimental teratogen. Experimental
reproductive effects. An eye and skin
irritant. Can cause nausea, headache,
daphoresis, hematuria, fever, anemia, liver
damage, vomiting, convulsions, and coma.
Poisoning may occur by ingestion of large
doses, inhalation, or skin absorption.
Questionable carcinogen with experimental
tumorigenic data. Flammable when exposed
to heat or flame; reacts with oxidizing
materials. Explosive reaction with dinitrogen
pentaoxide. Reacts violently with CrOs,
aluminum chloride + benzoyl chloride. Fires
in the benzene scrubbers of coke oven gas
plants have been attributed to oxidation of
naphthalene. Explosive in the form of vapor
or dust when exposed to heat or flame. To
fight fire, use water, CO2, dry chemical.
When heated to decomposition it emits
acrid smoke and irritating fumes. | [Hazardous Substances Data]
91-20-3(Hazardous Substances Data) | [IDLA]
250 ppm |
| Raw materials And Preparation Products | Back Directory | [Raw materials]
PETROLEUM ETHER-->Biphenyl-->KAOLIN-->COAL TAR-->COAL TAR-->Indene-->ETHYLENE-->1,2,3,4-Tetrahydronaphthalene-->Dodecylbenzene-->Technical naphthalene-->Phenol oil | [Preparation Products]
Phthalic anhydride-->1-Naphthol-->2-Naphthol-->Benzoic acid-->1-Naphthylamine-->Tannic acid-->Linolenic acid-->2-Amino-4,8-naphthalenedisulfonic acid-->DIBENZANTHRONE-->NAPHTHENIC ACID-->Peri acid-->1-Naphthaleneacetic acid-->1'-Acetonaphthone-->1-Aminonaphthalene-6-sulfonic acid-->5-Amino-1-naphthalenesulfonic acid-->Vat Yellow 2-->1,4,5,8-Naphthalenetetracarboxylic acid-->2-Methylbutane-->1-Iodonaphthalene-->Butylnaphtalenesulfonic Acid Sodium Salt-->1,5-Naphthalenedisulfonic acid-->Vat Yellow 4-->Vat Brown 5-->Slushing agent,high efficiency-->SEC-BUTYLAMINE-->BARIUM DINONYLNAPHTHALENESULFONATE-->Slushing agent-->1,5-Dihydroxy naphthalene-->synthetic fiber oil QDC-201-->disodium methylenebisnaphthalenesulphonate-->1-Nitronaphthalene-->Sodium poly[(naphthaleneformaldehyde)sulfonate]-->2,6-DIMETHYLNAPHTHALENE-->Dispersing agent DN-->dispersing agent CNF-->1-Naphthol-5-sulfonic acid |
| Hazard Information | Back Directory | [Reactivity Profile]
Vigorous reactions, sometimes amounting to explosions, can result from the contact between aromatic hydrocarbons, such as NAPHTHALENE, and strong oxidizing agents. They can react exothermically with bases and with diazo compounds. Substitution at the benzene nucleus occurs by halogenation (acid catalyst), nitration, sulfonation, and the Friedel-Crafts reaction. Naphthalene, camphor, glycerol, or turpentine will react violently with chromic anhydride [Haz. Chem. Data 1967. p 68]. Friedel-Crafts acylation of naphthalene using benzoyl chloride, catalyzed by AlCl3, must be conducted above the melting point of the mixture, or the reaction may be violent [Clar, E. et al., Tetrahedron, 1974, 30, 3296]. | [Air & Water Reactions]
Highly flammable. Insoluble in water. | [Hazard]
Toxic by inhalation. Upper respiratory tract
irritant, cataracts and hemolytic anemia. Possible
carcinogen. | [Health Hazard]
Fire may produce irritating and/or toxic gases. Contact may cause burns to skin and eyes. Contact with molten substance may cause severe burns to skin and eyes. Runoff from fire control may cause pollution. | [Potential Exposure]
Naphthalene is used as a chemical
intermediate or feedstock for synthesis of phthalic, anthranilic,
hydroxyl (naphthols), amino (naphthylamines), and sulfonic
compounds; which are used in the manufacture of
various dyes and in the preparation of phthalic anhydride, 1-naphthyl-N-methyl carbonate; and β-naphthol. Naphthalene
is also used in the manufacture of hydronaphthalenes, synthetic
resins; lampblack, smokeless powder; and celluloid.
Naphthalene has been used as a moth repellent.
Approximately 100 million people worldwide have G6PD
deficiency which would make them more susceptible to
hemolytic anemia on exposure to naphthalene. At present,
more than 80 variants of this enzyme deficiency have been
identified. The incidence of this deficiency is 0.1% in
American and European Caucasians, but can range as high
as 20% in American blacks and greater than 50% in certain
Jewish groups. Newborn infants have a similar sensitivity
to the hemolytic effects of naphthalene, even without
G6PD deficiency. | [Fire Hazard]
Flammable/combustible material. May be ignited by friction, heat, sparks or flames. Some may burn rapidly with flare burning effect. Powders, dusts, shavings, borings, turnings or cuttings may explode or burn with explosive violence. Substance may be transported in a molten form at a temperature that may be above its flash point. May re-ignite after fire is extinguished. | [First aid]
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including
resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical
attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit. | [Shipping]
UN1334 Naphthalene, crude or Naphthalene,
refined, Hazard Class: 4.1; Labels: 4.1-Flammable solid.
UN2304 (molten) Hazard Class: 4.1; Labels: 4.1-Flammable
solid. | [Incompatibilities]
Dust may form explosive mixture with
air. Incompatible with oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. Keep
away from alkaline materials, strong bases, strong acids,
oxoacids, epoxides. Violent reactions with chromium(III)
oxide, dinitrogen pentoxide; chromic anhydride. | [Waste Disposal]
Dissolve or mix the material
with a combustible solvent and burn in a chemical incinerator
equipped with an afterburner and scrubber. All federal,
state, and local environmental regulations must be
observed. Consult with environmental regulatory agencies
for guidance on acceptable disposal practices. Generators
of waste containing this contaminant (≥100 kg/mo) must
conform with EPA regulations governing storage, transportation,
treatment, and waste disposal. | [History]
In 1819, naphthalene was obtained as white crystals during the pyrolysis of coal tar by John
Kidd (1775–1851), a British physician and chemist, and Alexander Garden (1757–1829), an
American living in Britain. Kidd described the properties of the white crystals he obtained
from coal tar and proposed the named naphthaline for the substance; naphthaline was
derived from naphtha, a general term for a volatile, fl ammable, hydrocarbon liquid. Michael
Faraday (1791–1867) determined the correct empirical formula for naphthalene in 1825,
and Richard August Carl Emil Erlenmeyer (1825–1909) proposed the fused benzene ring
structure in 1866. | [Definition]
ChEBI: An aromatic hydrocarbon comprising two fused benzene rings. It occurs in the essential oils of numerous plant species e.g. magnolia. | [Definition]
naphthalene: A white volatilesolid, C10H8; r.d. 1.025;m.p. 80.55°C; b.p. 218°C. Naphthaleneis an aromatic hydrocarbon withan odour of mothballs and is obtainedfrom crude oil. It is a raw materialfor making certain syntheticresins. | [Production Methods]
Naphthalene is produced from coal tar or petroleum. It is made from petroleum by dealkylationof methylnaphthalenes in the presence of hydrogen at high temperature and pressure.Petroleum was a major source of naphthalene until the 1980s, but now most naphthaleneis produced from coal tar. The pyrolysis of bituminous coal produces coke and coke ovengases. Naphthalene is condensed by cooling the coke gas and then separated from the gas. | [Synthesis Reference(s)]
Journal of the American Chemical Society, 96, p. 3686, 1974 DOI: 10.1021/ja00818a072
The Journal of Organic Chemistry, 54, p. 4474, 1989 DOI: 10.1021/jo00279a046
Tetrahedron Letters, 27, p. 5541, 1986 DOI: 10.1016/S0040-4039(00)85262-4 | [General Description]
Heterogeneous ozonolysis of naphthalene adsorbed on XAD-4 resin has been studied using annular denuder technique. | [Flammability and Explosibility]
Flammable | [Carcinogenicity]
Naphthalene is reasonably anticipated to be a human carcinogenbased on sufficient evidence from studies in experimental animals. | [Source]
Schauer et al. (1999) reported naphthalene in diesel fuel at a concentration of 600 μg/g
and in a diesel-powered medium-duty truck exhaust at an emission rate of 617 μg/km. Detected in
distilled water-soluble fractions of 87 octane gasoline (0.24 mg/L), 94 octane gasoline (0.21
mg/L), Gasohol (0.29 mg/L), No. 2 fuel oil (0.60 mg/L), jet fuel A (0.34 mg/L), diesel fuel (0.25
mg/L), military jet fuel JP-4 (0.18 mg/L) (Potter, 1996), and used motor oil (116 to 117 μg/L)
(Chen et al., 1994). Lee et al. (1992) investigated the partitioning of aromatic hydrocarbons into
water. They reported concentration ranges from 350 to 1,500 mg/L and 80 to 300 μg/L in diesel
fuel and the corresponding aqueous phase (distilled water), respectively. Diesel fuel obtained from
a service station in Schlieren, Switzerland contained 708 mg/L naphthalene (Schluep et al., 2001).
California Phase II reformulated gasoline contained naphthalene at a concentration of 1.04 g/kg.
Gas-phase tailpipe emission rates from gasoline-powered automobiles with and without catalytic
converters were approximately 1.00 and 50.0 mg/km, respectively (Schauer et al., 2002).
Thomas and Delfino (1991) equilibrated contaminant-free groundwater collected from
Gainesville, FL with individual fractions of three individual petroleum products at 24–25 °C for
24 h. The aqueous phase was analyzed for organic compounds via U.S. EPA approved test method
625. Average naphthalene concentrations reported in water-soluble fractions unleaded gasoline,
kerosene, and diesel fuel were 989, 644, and 167 ug/L.
Based on laboratory analysis of 7 coal tar samples, naphthalene concentrations ranged from 940
to 71,000 ppm (EPRI, 1990). Detected in 1-yr aged coal tar film and bulk coal tar at concentraions
of 26,000 and 29,000 mg/kg, respectively (Nelson et al., 1996). A high-temperature coal tar
contained naphthalene at an average concentration of 8.80 wt % (McNeil, 1983). Nine
commercially available creosote samples contained naphhalene at concentrations ranging from
3,800 to 52,000 mg/kg (Kohler et al., 2000). Lee et al. (1992a) equilibrated eight coal tars with
distilled water at 25 °C. The maximum concentration of naphthalene observed in the aqueous
phase was 14 mg/L.
Naphthalene was detected in soot generated from underventilated combustion of natural gas
doped with toluene (3 mole %) (Tolocka and Miller, 1995).
Typical concentration in a heavy pyrolysis oil is 17.8 wt % (Chevron Phillips, May 2003).
Detected in asphalt fumes at an average concentration of 1.15 ng/m3 (Wang et al., 2001).
An impurity identified in commercially available acenaphthene (Marciniak, 2002).
Schauer et al. (2001) measured organic compound emission rates for volatile organic compounds,
gas-phase semi-volatile organic compounds, and particle-phase organic compounds from
the residential (fireplace) combustion of pine, oak, and eucalyptus. The gas-phase emission rate of
naphthalene was 227 mg/kg of pine burned. Emission rates of naphthalene were not measured
during the combustion of oak and eucalyptus. | [Environmental Fate]
Biological. In activated sludge, 9.0% of the applied amount mineralized to carbon dioxide after 5 d (Freitag et al., 1985). Under certain conditions, Pseudomonas sp. oxidized naphthalene to cis- 1,2-dihydro-1,2-dihydroxynaphthalene (Dagley, 1972). This metabolite may be oxidized by Pseudomonas putida to carbon dioxide and water (Jerina et al., 1971). Under aerobic conditions, Cunninghamella elegans degraded naphthalene to 1-naphthol, 2-naphthol, trans-1,2-dihydroxy 1,2-dihydronaphthalene, 4-hydroxy-1-tetralone, and 1,4-naphthoquinone. Under aerobic conditions, Agnenellum, Oscillatoria, and Anabaena degraded naphthalene to 1-naphthol, cis-1,2- dihydroxy-1,2-dihydronaphthalene, and 4-hydroxy-1-tetralone (Kobayashi and Rittman, 1982; Riser-Roberts, 1992). Candida lipolytica, Candida elegans, and species of Cunninghamella, Syncephalastrum and Mucor oxidized naphthalene to 1-naphthol, 2-naphthol, trans-1,2- dihydroxy-1,2-dihydronaphthalene, 4-hydroxy-1-tetralone, 1,2-naphthoquinone, and 1,4-naphthouinone (Cerniglia et al., 1978, 1980; Dodge and Gibson, 1980).
Soil. The half-lives of naphthalene in pristine and oil-contaminated sediments are >88 d and 4.9 h, respectively (Herbes and Schwall, 1978). Reported half-lives for naphthalene in a Kidman sandy loam and McLaurin sandy loam are 2.1 and 2.2 d, respectively (Park et al., 1990).
Surface Water. The volatilization half-life of naphthalene from surface water (1 m deep, water velocity 0.5 m/sec, wind velocity 22.5 m/sec) using experimentally determined Henry’s law constants is estimated to be 16 h (Southworth, 1979). The reported half-lives of naphthalene in an oil-contaminated estuarine stream, clean estuarine stream, coastal waters, and in the Gulf stream are 7, 24, 63, and 1,700 d, respectively (Lee, 1977). Mackay and Wolkoff (1973) estimated an evaporation half-life of 2.9 h from a surface water body that is 25 °C and 1 m deep. In a laboratory experiment, the average volatilization half-life of naphthalene in a stirred water vessel (outer dimensions 22 x 10 x 21 cm) at 23 °C and an air flow rate of 0.20 m/sec is 380 min. The half-life was independent of wind velocity or humidity but very dependent upon temperature (Kl?pffer et al., 1982).
Groundwater. The estimated half-life of naphthalene in groundwater in the Netherlands was 6 months (Zoeteman et al., 1981). Nielsen et al. (1996) studied the degradation of naphthalene in a shallow, glaciofluvial, unconfined sandy aquifer in Jutland, Denmark. As part of the in situ microcosm study, a cylinder that was open at the bottom and screened at the top was installed through a cased borehole approximately 5 m below grade. Five liters of water was aerated with atmospheric air to ensure aerobic conditions were maintained. Groundwater was analyzed weekly for approximately 3 months to determine naphthalene concentrations with time. The experimentally determined first-order biodegradation rate constant and corresponding half-life following a 6-d lag phase were 0.8/d and 20.8 h, respectively.
Photolytic. Irradiation of naphthalene and nitrogen dioxide using a high pressure mercury lamp (λ >290 nm) yielded the following principal products: 1- and 2-hydroxynaphthalene, 1-hydroxy-2- nitronaphthalene, 1-nitronaphthalene, 2,3-dinitronaphthalene, phthalic anhydride, 1,3-, 1,5- and 1,8-dinitronaphthalene (Barlas and Parlar, 1987). In a similar experiment, naphthalene crystals was heated to 50 °C and exposed to pure air containing NO and OH radicals. Photodecomposition followed first-order kinetics indicating the concentration of OH radicals remained constant throughout the reaction. Degradation products identified by GC/MS were 1-naphthol, 2-naphthol, 1-nitronaphthalene, 2-nitronaphthalene, 1,4-naphthoquinone, 1,4-naphthoquinone-2,3-epoxide, 3- nitrophthalic anhydride, phthalic anhydride, 4-methyl-2H-1-benzopyran-2-one, 1(3H)-isobenzofuranone, 1,2-benzenecarboxaldehyde, cis-2-formyl-cinnamaldehyde, trans-2-formylcinnamaldehyde, and phthalide. The following compounds were tentatively identified: 2,7-naphthalenediol, 2-nitro-1-naphthol, 4-nitro-1-naphthol, and 2,4-dinitro-1-naphthol. Photoproducts identified by HPLC included: benzoic acid, cinnamic acid, 2,4-dinitro-1-naphthol, 2-formylcinnamic acid, cis-2-formylcinnamaldehyde, trans-2-formylcinnamaldehyde, 1-nitronaphthalene, 2-nitronaphthalene, 1-naphthol, 2-naphthol, 1,4-naphthoquinone, 1,4-naphthoquinone-2,3-epoxide, 3-nitrophthalic anhydride, oxalic acid, phthalic acid, phthalaldehyde, and phthalide (Lane et al., 1997).
| [Purification Methods]
Crystallise naphthalene once or more times from the following solvents: EtOH, MeOH, CCl4, *C6H6, glacial acetic acid, acetone or diethyl ether, followed by drying at 60o in an Abderhalden drying apparatus. It has also been purified by vacuum sublimation and by fractional crystallisation from its melt. Other purification procedures include refluxing in EtOH over Raney Ni and chromatography of a CCl4 solution on alumina with *benzene as eluting solvent. Baly and Tuck [J Chem Soc 1902 1908] purified naphthalene for spectroscopy by heating with conc H2SO4 and MnO2, followed by steam distillation (repeating the process), and formation of the picrate which, after recrystallisation (m 150o) is decomposed with base and the naphthalene is steam distilled. It is then crystallised from dilute EtOH. It can be dried over P2O5 under vacuum (take care not to make it sublime). Also purify it by sublimation and subsequent crystallisation from cyclohexane. Alternatively, it has been washed at 85o with 10% NaOH to remove phenols, with 50% NaOH to remove nitriles, with 10% H2SO4 to remove organic bases, and with 0.8g AlCl3 to remove thianaphthalenes and various alkyl derivatives. Then it is treated with 20% H2SO4, 15% Na2CO3 and finally distilled. [Gorman et al. J Am Chem Soc 107 4404 1985.] Zone refining purified naphthalene from anthracene, 2,4-dinitrophenylhydrazine, methyl violet, benzoic acid, methyl red, chrysene, pentacene and indoline. [Beilstein 5 IV 1640.] | [Toxicity evaluation]
Systemic absorption of naphthalene vapor may result in
cataracts. The biochemical basis for naphthalene cataract has
been investigated. Naphthalene is metabolized in the liver to
1,2-dihydro-1,2-dihydroxynaphthalene. Lenticular catechol
reductase biotransforms 1,2-dihydro-1,2-dihydroxynaphthalene
to 1,2-dihydroxynaphthalene, which, in turn, is
auto-oxidized in air at neutral pH to 1,2-naphthoquinone
and hydrogen peroxide. Ascorbic acid reverses the latter
reaction and forms dehydroascorbic acid, which diffuses out
of the lens very slowly. Dehydroascorbic acid has been
shown to accumulate in the lens of rabbits that were fed
naphthalene and lens incubated in vitro with 1,2-dihydro-
1,2-dihydroxynaphthalene. The sequence of reactions
involves the reduction of ascorbic acid by 1,2-naphthoquinone
in the aqueous humor to dehydroascorbic acid,
which rapidly penetrates the lens and is reduced by glutathione.
Oxidized glutathione and 1,2-naphthoquinone may
compete for enzyme glutathione reductase, which normally
maintains high reticular levels of reduced glutathione. A
reduction in the concentration of these coupled with the
removal of oxygen from the aqueous humor due to the autooxidation
of 1,2-dihydroxynaphthalene may make the lens
sensitive to naphthalene toxicity. | [References]
Formation Mechanisms of Naphthalene and Indene: From the Interstellar Medium to Combustion Flames. DOI:10.1021/acs.jpca.6b09735
Functional Naphthalene Diimides: Synthesis, Properties, and Applications. DOI:10.1021/ACS.CHEMREV.6B00160
The 100 Most Important Chemical Compounds: A Reference Guide DOI:10.5860/choice.45-3798
A comprehensive guide to the hazardous properties of chemical substances DOI:10.1002/9780470134955
A Dictionary of Chemistry (6th edition) DOI:10.1108/09504120910935291
TOXICOLOGICAL REVIEW of NAPHTHALENE
Naphthalene - Environmental Protection Agency |
| Questions And Answer | Back Directory | [description]
Naphthalene is a white solid chemical that vaporizes easily. It has a strong smell. You can sometimes smell naphthalene in the air or in water. Called white tar and tar camphor, naphthalene is used in mothballs and moth flakes. Petroleum and coal contain naphthalene.
Naphthalene, the simplest of the fused or condensed ring hydrocarbon compounds composed of two benzene rings sharing two adjacent carbon atoms. Naphthalene is the most abundant single constituent of coal tar, a volatile product from the destructive distillation of coal, and is also formed in modern processes for the high-temperature cracking (breaking up of large molecules) of petroleum.
1-Methylnaphthalene and 2-methylnaphthalene are naphthalene-related compounds. 1-Methylnaphthalene is a clear liquid and 2-methylnaphthalene is a solid; both can be smelled in air and in water at very low concentrations. 1-Methylnaphthalene and 2-methylnaphthalene are used to make other chemicals such as dyes and resins. 2-Methylnaphthalene is also used to make vitamin K.
| [Chemical Properties]
Naphthalene is a crystalline, white, flammable, polycyclic aromatic hydrocarbon consisting of two fused benzene rings. It has a pungent odor and sublimes readily above its melting point; it has been traditionally used in moth balls and is responsible for the moth balls characteristic odor. Naphthalene is a natural component of fossil fuels and is the single most abundant component of coal tar, accounting for approximately 11% of dry coal tar. | [Uses]
- In industry, naphthalene is used to manufacture a plastic called polyvinyl chloride (PVC). In public restrooms, naphthalene can be found in toilet deodorant blocks. At home, naphthalene can be found in moth repellents.
- Naphthalene balls are extensively used as household preservative of woolen clothes and as a deodorant tablet for the toilets, urinals, bathrooms etc. These are manufactured from naphthalene flakes by a tabletmaking machine having its ball shape die.
- Naphthalene is an important hydrocarbon raw material and is primarily used to manufacture phthalic anhydride and polyvinyl chloride (PVC) plastics, but is also used in moth repellents and toilet deodorant blocks.
- Naphthalene was used in liquid-phase exfoliation of graphite in organic solvents for the production of graphene sheets. It was used in preparation of carbon-coated Si 70 Sn 30 nanoparticles.
- It was used as fluorescent probe to study the aggregation behavior of sodium cholate.
- It was used to investigate influence of added short chain linear and branched alcohols on the binding of 1:1 complex of naphthalene and β-cyclodextrin.
| [Health Hazard]
Most of the data available on the toxic effects of naphthalene have been derived from animal studies conducted either in vivo or with in vitro preparations.
Rats and mice breathing naphthalene vapors daily for a lifetime had irritated noses and nose tumors and irritated lungs. Some female mice had lung tumors. Some animals got cloudy eyes after ingesting it.
It is not clear if naphthalene causes reproductive problems in animals. Although there is no direct data showing that naphthalene can cause cancer in people, naphthalene exposure can lead to cancer in animals.
Exposure to large amounts of naphthalene may damage or destroy red blood cells, a condition called hemolytic anemia. Symptoms of hemolytic anemia are feeling very tired or restless, lack of appetite, and pale skin. Exposure to large amounts of naphthalene may also cause upset stomach, diarrhea, blood in the urine,and yellow-colored skin. Very young children and unborn children are at higher risk if they are exposed to naphthalene, especially if they ingest the chemical. Some infants have become ill when they were close to clothing or blankets stored in naphthalene mothballs.
| [Toxicity]
Naphthalene is a white solid substance with a strong smell. Poisoning from naphthalene destroys or changes red blood cells so they cannot carry oxygen. This can cause organ damage.
In humans, naphthalene is broken down to alpha-naphthol, which is linked to the development of hemolytic anemia. Kidney and liver damage may also occur. Alpha-naphthol and other metabolites are excreted in urine.
In animals, naphthalene breaks down into other compounds including alpha-naphthol, which may affect the lungs and eyes. Naphthalene was found in the milk of exposed cows, but the residues disappeared quickly after the cows were no longer exposed. Nearly all the naphthalene was broken down into other compounds and excreted in their urine.
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