98-82-8 Usage
Chemical Description
Cumene is an aromatic hydrocarbon that is used as a solvent and in the production of phenol and acetone.
Uses
Used in Chemical Industry:
Cumene is used as a starting material in the production of phenol, acetone, and α-methylstyrene. It is also used as an intermediate for agrochemicals and a solvent in various industrial processes.
Used in Pharmaceutical Industry:
Cumene hydroperoxide is used to probe isoenzyme specificity as well as region-and stereo-selectivity, and it produces oxidative stress in various steps of protein synthesis.
Used in Paint and Coatings Industry:
Cumene is used as a thinner for paints, lacquers, and enamels.
Used in Manufacturing Industry:
Cumene is used in the production of methyl styrene and acetophenone, as well as a solvent in the manufacture of iron, rubber, and steel, as well as paper and pulp.
Used in Petroleum Industry:
Cumene is used as a constituent of some petroleum-based solvents, such as naphtha, and in gasoline blending, diesel fuel, and high-octane aviation fuel.
Used in Plastics and Polymer Industry:
Cumene is an important industrial intermediate in the manufacture of phenolic and polycarbonate resins, nylon, and epoxy.
Production
Isopropylbenzene can be generated by alkylation or reacting benzene and propylene in the presence of an acid catalyst (1). Most of the modern plants that produce cumene use phosphoric acid as a catalyst, while some use a Friedel-Crafts reaction with aluminum trichloride (1). The reactions involved in the production of cumene from benzene and propylene are as follows:
C3H6 + C6H6 = C6H5-C3H7
The catalytic process that is usually optimized at 25 atm. and 350oC is the best technology for the production of isopropylbenzene
Environmental Effects
Cumene vaporizes when released into the air where it is immediately reacted into other chemicals. However, in soil and water, bacteria degrade the chemical. Industrial emissions of the compound can lead to elevated concentrations in the atmosphere around the source.
Safety Information
Primarily, humans are exposed to cumene at industrial workplaces that use or produce the compound (2). However, reports have indicated low exposure concentrations during the production of cumene. On the other hand, succeeding reactions of the compound may occur in closed systems.
Employers and workers must follow safe handling practices that are often found in the Manufacturer's Safety Data Sheet to enhance employee safety. Inhalation exposure to the chemical may cause drowsiness, dizziness, headaches, unconsciousness, and slight incoordination. It is an irritant when exposed to the skin and eye.
As such, workers should wear protective clothing, gloves, respirators, and safety goggles. Furthermore, workplaces that cumene is being handled or produced should be well-ventilated to minimize the potential for employee exposure.
Air & Water Reactions
Flammable. Insoluble in water.
Reactivity Profile
Mixing CUMENE in equal molar portions with any of the following substances in a closed container caused the temperature and pressure to increase: chlorosulfonic acid, nitric acid, oleum, NFPA 1991.
Hazard
Toxic by ingestion, inhalation, and skin
absorption; a narcotic. Moderate fire risk. Eye, skin,
and upper respiratory tract irritant, and central nervous system impairment. Possible carcinogen.
Health Hazard
Narcotic action with long-lasting effects; depressant to central nervous system. Acute (short-term) inhalation exposure to cumene may cause headaches, dizziness, drowsiness, slight incoordination, and unconsciousness in humans. Cumene has a potent central nervous system (CNS) depressant action characterized by a slow induction period and long duration of narcotic effects in animals. Cumene is a skin and eye irritant. No information is available on the chronic (long-term), reproductive, developmental, or carcinogenic effects of cumene in humans. Animal studies have reported increased liver, kidney, and adrenal weights from inhalation exposure to cumene. EPA has classified cumene as a Group D, not classifiable as to human carcinogenicity.
Health Hazard
Cumene is an irritant to the eyes, skin, andupper respiratory system, and a low acutetoxicant. It is narcotic at high concentrations.The narcotic effect is induced slowly andis of longer duration relative to benzeneand toluene (ACGIH 1986). Although thetoxicity may be of same order, the hazardfrom inhalation is low due to its high boilingpoint and low vapor pressure. An exposureto 8000 ppm for 4 hours was lethal to rats.The oral toxicity of cumene was determinedto be low in animals. In addition to narcosis, itcaused gastritis. An LD50 value documentedfor mice is 1400 mg/kg (NIOSH 1986).Chronic inhalation toxicity of cumene wasvery low in animals. Repeated exposurescaused congestion in the lungs, liver, andkidney and an increase in the kidney weight.A major portion of cumene absorbed into the body is metabolized in the liver andexcreted. The urinary metabolites constitutedconjugated alcohols or acids.
Safety Profile
Moderately toxic by
ingestion. Mdly toxic by inhalation and skincontact. Human systemic effects by
inhalation: an antipsychotic, unspecified
changes in the sense of smell and respiratory
system. An eye and skin irritant. Potential
narcotic action. Central nervous system
depressant. There is no apparent difference
between the toxicity of natural cumene and
that derived from petroleum. See also
BENZENE and TOLUENE. Flammable
liquid when exposed to heat or flame; can
react with oxidizing materials. Violent
reaction with HNO3, oleum, chlorosulfonic
acid. To fight fKe, use foam, CO2, dry
chemical.
Potential Exposure
Cumene is a constituent of crude oil and finished fuels. It is released to the environment as a result of its production and processing from petroleum refining, the evaporation and combustion of petroleum products, and by the use of a variety of products containing cumene. The most probable route of human exposure is by the inhalation of contaminated air from the evaporation of petroleum products. Exposure may also occur through the consumption of contaminated food or water.
Potential Exposure
Cumene is used primarily in the manufacture acetone and phenol which are widely used as solvents for paints, laquers, and varnishes and to make plastics. Cumene is used in gasoline blending and as a high-octane gasoline component. It is also found as a component in tobacco smoke.
Carcinogenicity
Cumene was not a developmental toxicant
in either rats or rabbits after exposure to levels
(1200ppm and 2300ppm, respectively) associated
with maternal toxicity.9 Most genotoxic
tests with cumene have been negative.
The LD50 for penetration of rabbit skin
was 12.3 ml/kg after 14 days.4 Contact of the
liquid with the skin causes erythema and irritation.
11 Eye contamination may produce conjunctival
irritation.
It generally is agreed that cumene has no
damaging effect on the hematopoietic system,
despite its chemical similarity to benzene.5
Furthermore, cumene is not anticipated to be
a significant carcinogenic hazard because it is
metabolically similar to toluene, a substance
that showed no carcinogenic activity in 2-year
inhalation studies.
Source
As of October 1995, no MCLGs or MCLs have been proposed
although isopropylbenzene has been listed for regulation (U.S. EPA, 1996). A DWEL of 400 μg/L
was recommended (U.S. EPA, 2000).
Detected in distilled water-soluble fractions of 94 octane gasoline and Gasohol at
concentrations of 0.14 and 0.15 mg/L, respectively (Potter, 1996).
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
602. Average isopropylbenzene concentrations reported in water-soluble fractions of unleaded
gasoline and kerosene were 235 and 28 μg/L, respectively. When the authors analyzed the
aqueous-phase via U.S. EPA approved test method 610, average isopropylbenzene concentrations
in water-soluble fractions of unleaded gasoline and kerosene were lower, i.e., 206 and 22 μg/L,
respectively. Isopropylbenzene was detected in both water-soluble fractions of diesel fuel but were
not quantified.
Isopropylbenzene was detected in California Phase II reformulated gasoline at a concentration
of 830 mg/kg (Schauer et al., 2002).Isopropylbenzene naturally occurs in Ceylon cinnamon, cumin, and ginger (1 ppm in rhizome)
(Duke, 1992).
Environmental fate
ological. When isopropylbenzene was incubated with Pseudomonas putida, the substrate was converted to ortho-dihydroxy compounds in which the isopropyl part of the compound remained
intact (Gibson, 1968). Oxidation of isopropylbenzene by Pseudomonas desmolytica S44B1 and
Pseudomonas convexa S107B1 yielded 3-isopropylcatechol and a ring fission product, (+)-2-
hydroxy-7-methyl-6-oxooctanoic acid (Jigami et al., 1975).
Surface Water. Mackay and Wolkoff (1973) estimated an evaporation half-life of 14.2 min from
a surface water body that is 25 °C and 1 m deep.
Photolytic. Major products reported from the photooxidation of isopropylbenzene with nitrogen
oxides include nitric acid and benzaldehyde (Altshuller, 1983). A n-hexane solution containing
isopropylbenzene and spread as a thin film (4 mm) on cold water (10 °C) was irradiated by a
mercury medium pressure lamp. In 3 h, 22% of the applied isopropylbenzene photooxidized into
α,α-dimethylbenzyl alcohol, 2-phenylpropionaldehyde, and allylbenzene (Moza and Feicht,
1989).
A rate constant of 3.7 x 109 L/molecule·sec was reported for the reaction of isopropylbenzene
with OH radicals in the gas phase (Darnall et al., 1976). Similarly, a room temperature rate
constant of 6.6 x 10-12 cm3/molecule·sec was reported for the vapor-phase reaction of
isopropylbenzene with OH radicals (Atkinson, 1985). At 25 °C, a rate constant of 6.25 x 10-12
cm3/molecule·sec was reported for the same reaction (Ohta and Ohyama, 1985).
Chemical/Physical. Complete combustion in air yields carbon dioxide and water vapor.
Isopropylbenzene will not hydrolyze because it does not contain a hydrolyzable functional
group.
The calculated evaporation half-life of isopropylbenzene from surface water 1 m deep at 25 °C
is 5.79 h (Mackay and Leinonen, 1975).
Shipping
UN1918 Cumene, Hazard Class: 3; Labels: 3-Flammable liquid
Toxicity evaluation
Cumene is released into the environment as a result of
production and processing from petroleum refining and the
evaporation and combustion of petroleum products. Cumene
also occurs in a variety of natural substances including
essential oils from plants and foodstuffs. When released to
soil, cumene is expected to biodegrade and may volatilize
from the soil surface. Cumene is expected to have low
mobility based on its estimated adsorption coefficient (Koc) of
820. Based on Henry’s law constant of 0.0115 atm m3 mol-1,
cumene volatilization from moist soil surfaces is expected to
be an important environmental fate and it may volatilize from
dry soil surfaces based on its vapor pressure. Cumene is
expected to strongly adsorb to soils and is not expected to
leach to groundwater.When released into the atmosphere, a vapor pressure of
4.5 mmHg at 25°C indicates that cumene exists solely as
a vapor in the ambient atmosphere. Cumene in the vapor
phase reacts with photochemically generated hydroxyl radicals.
The reaction of cumene in the vapor phase with ozone has an
estimated half-life of 2.5 days. Cumene may also react with
ozone radicals found in the atmosphere but not at an environmentally
important rate.
Incompatibilities
Vapor may form explosive mixture with air. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, 942 Cumene fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong bases, strong acids, oxoacids, epoxides. Air contact forms cumene hydroperoxide. Attacks rubber. May accumulate static electrical charges, and may cause ignition of its vapors.
Check Digit Verification of cas no
The CAS Registry Mumber 98-82-8 includes 5 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 2 digits, 9 and 8 respectively; the second part has 2 digits, 8 and 2 respectively.
Calculate Digit Verification of CAS Registry Number 98-82:
(4*9)+(3*8)+(2*8)+(1*2)=78
78 % 10 = 8
So 98-82-8 is a valid CAS Registry Number.
InChI:InChI=1/C9H12/c1-8(2)9-6-4-3-5-7-9/h3-8H,1-2H3
98-82-8Relevant articles and documents
On the Mechanism of Reductive Cleavage of the Carbon-Nitrogen Bond of Aliphatic Nitro Compounds with Tributyltin Hydride
Kamimura, Akio,Ono, Noboru
, p. 3629 - 3636 (1988)
Denitrohydrogenation reaction of aliphatic nitro compounds with tributyltin hydride (Bu3SnH) is accelerated in the presence of radical initiators.ESR and electrochemical measurements reveal that the reductive cleavage of the carbon-nitrogen bond proceeds not via anion radicals of nitro compounds such as SRN1 reaction but via β-scission of (tributylstannyloxy)nitroxyl radicals.The relative reactivities of tin radicals toward substituted α-nitrocumenes, α-nitroethylbenzenes, and α-nitropropiophenones exhibits excellent Hammett correlations with positive ρ values.This tendency has also been found in the reaction of benzyl halides with tin radical.These results suggest that the carbon-nitrogen bond breaking from nitroxyl radical intermediates should take place in rate-determining step for the reaction.
Large bite bisphosphite, 2,6-C5H3N{CH2OP(-OC10H6)(μ-S)(C10H6O-)}2: Synthesis, derivatization, transition metal chemistry and application towards hydrogenation of olefi
Punji, Benudhar,Balakrishna, Maravanji S.
, p. 1683 - 1689 (2007)
Large bite bisphosphite ligand, 2,6-C5H3N{CH2OP(-OC10H6)(μ-S)(C10H6O-)}2 (2), is obtained by reacting chlorophosphite, {-OC10H6(μ-S)C10/sub
Gas-liquid and gas-liquid-solid catalysis in a mesh microreactor
Abdallah, Radwan,Meille, Valerie,Shaw, John,Wenn, David,De Bellefon, Claude
, p. 372 - 373 (2004)
A microstructured mesh contactor that can offer residence time of more than minutes is used for gas-liquid-solid hydrogenations and gas-liquid asymmetric hydrogenations. Applications for catalyst/chiral inductor screening and for kinetic data acquisition
Mechanistic investigations of imine hydrogenation catalyzed by dinuclear iridium complexes
Martin, Marta,Sola, Eduardo,Tejero, Santiago,Lopez, Jose A.,Oro, Luis A.
, p. 4057 - 4068 (2006)
Treatment of [Ir2(μ-H)(μ-Pz)2H 3(NCMe)(PiPr3)2] (1) with one equivalent of HBF4 or [PhNH= CHPh]BF4 affords efficient catalysts for the homogeneous hydrogenation of N-benzylidenea
Effect of Surface Fluorination with CClF3 on Catalytic Activity of SiO2-Al2O3 for Alkylation of Benzene with Propene
Kurosaki, Akito,Okazaki, Susumu
, p. 2363 - 2367 (1990)
For surface modification, the vapor-phase fluorination of SiO2-Al2O3 with CClF3 was carried out at various temperatures ranging from 350 to 550 deg C in a conventional flow recator.It was found that surface fluorination at about 400 deg C was especially e
Protodesilylation of Arylsilanes by Visible-Light Photocatalysis
García Manche?o, Olga,Kuhlmann, Jan H.,Uygur, Mustafa
, p. 1689 - 1694 (2022/03/14)
The first visible-light-mediated photocatalytic, metal- and base-free protodesilylation of arylsilanes is presented. The C(sp2)-Si bond cleavage process is catalyzed by a 5 mol % loading of a commercially available acridinium salt upon blue-light irradiation. Two simple approaches have been identified employing either aerobic or hydrogen atom transfer cocatalytic conditions, which enable the efficient and selective desilylation of a broad variety of simple and complex arylsilanes under mild conditions.
One-step conversion of lignin-derived alkylphenols to light arenes by co-breaking of C-O and C-C bonds
Di, Yali,Li, Guangyu,Li, Zhiqin,Liu, Weiwei,Qiu, Zegang,Ren, Xiaoxiong,Wang, Ying
, p. 2710 - 2721 (2022/02/21)
The conversion of lignin-derived alkylphenols to light arenes by a one-step reaction is still a challenge. A 'shortcut' route to transform alkylphenols via the co-breaking of C-O and C-C bonds is presented in this paper. The catalytic transformation of 4-ethylphenol in the presence of H2 was used to test the breaking of C-O and C-C bonds. It was found that the conversion of 4-ethylphenol was nearly 100%, and the main products were light arenes (benzene and toluene) and ethylbenzene under the catalysis of Cr2O3/Al2O3. The conversion of 4-ethylphenol and the selectivity of the products were significantly influenced by the reaction temperature. The selectivity for light arenes reached 55.7% and the selectivity for overall arenes was as high as 84.0% under suitable reaction conditions. Such results confirmed that the co-breaking of the C-O and C-C bonds of 4-ethylphenol on a single catalyst by one step was achieved with high efficiency. The adsorption configuration of the 4-ethylphenol molecule on the catalyst played an important role in the breaking of the C-O and C-C bonds. Two special adsorption configurations of 4-ethylphenol, including a parallel adsorption and a vertical adsorption, might exist in the reaction process, as revealed by DFT calculations. They were related to the breaking of C-O and C-C bonds, respectively. A path for the hydrogenation reaction of 4-ethylphenol on Cr2O3/Al2O3 was proposed. Furthermore, the co-breaking of the C-O and C-C bonds was also achieved in the hydrogenation reactions of several alkylphenols. This journal is
Radical induced disproportionation of alcohols assisted by iodide under acidic conditions
Huang, Yang,Jiang, Haiwei,Li, Teng,Peng, Yang,Rong, Nianxin,Shi, Hexian,Yang, Weiran
supporting information, p. 8108 - 8115 (2021/10/29)
The disproportionation of alcohols without an additional reductant and oxidant to simultaneously form alkanes and aldehydes/ketones represents an atom-economical transformation. However, only limited methodologies have been reported, and they suffer from a narrow substrate scope or harsh reaction conditions. Herein, we report that alcohol disproportionation can proceed with high efficiency catalyzed by iodide under acidic conditions. This method exhibits high functional group tolerance including aryl alcohol derivatives with both electron-withdrawing and electron-donating groups, furan ring alcohol derivatives, allyl alcohol derivatives, and dihydric alcohols. Under the optimized reaction conditions, a 49% yield of 5-methyl furfural and a 49% yield of 2,5-diformylfuran were obtained simultaneously from 5-hydroxymethylfurfural. An initial mechanistic study suggested that the hydrogen transfer during this redox disproportionation occurred through the inter-transformation of HI and I2. Radical intermediates were involved during this reaction.
Ligand-enabled and magnesium-activated hydrogenation with earth-abundant cobalt catalysts
Han, Bo,Jiao, Hongmei,Ma, Haojie,Wang, Jijiang,Zhang, Miaomiao,Zhang, Yuqi
, p. 39934 - 39939 (2021/12/31)
Replacing expensive noble metals like Pt, Pd, Ir, Ru, and Rh with inexpensive earth-abundant metals like cobalt (Co) is attracting wider research interest in catalysis. Cobalt catalysts are now undergoing a renaissance in hydrogenation reactions. Herein, we describe a hydrogenation method for polycyclic aromatic hydrocarbons (PAHs) and olefins with a magnesium-activated earth-abundant Co catalyst. When diketimine was used as a ligand, simple and inexpensive metal salts of CoBr2in combination with magnesium showed high catalytic activity in the site-selective hydrogenation of challenging PAHs under mild conditions. Co-catalyzed hydrogenation enabled the reduction of two side aromatics of PAHs. A wide range of PAHs can be hydrogenated in a site-selective manner, which provides a cost-effective, clean, and selective strategy to prepare partially reduced polycyclic hydrocarbon motifs that are otherwise difficult to prepare by common methods. The use of well-defined diketimine-ligated Co complexes as precatalysts for selective hydrogenation of PAHs and olefins is also demonstrated.
Reductive activation and hydrofunctionalization of olefins by multiphoton tandem photoredox catalysis
Czyz, Milena L.,Taylor, Mitchell S.,Horngren, Tyra H.,Polyzos, Anastasios
, p. 5472 - 5480 (2021/06/01)
The conversion of olefin feedstocks to architecturally complex alkanes represents an important strategy in the expedient generation of valuable molecules for the chemical and life sciences. Synthetic approaches are reliant on the electrophilic activation of unactivated olefins, necessitating functionalization with nucleophiles. However, the reductive functionalization of unactivated and less activated olefins with electrophiles remains an ongoing challenge in synthetic chemistry. Here, we report the nucleophilic activation of inert styrenes through a photoinduced direct single electron reduction to the corresponding nucleophilic radical anion. Central to this approach is the multiphoton tandem photoredox cycle of the iridium photocatalyst [Ir(ppy)2(dtbbpy)] PF6, which triggers in situ formation of a high-energy photoreductant that selectively reduces styrene olefinic π bonds to radical anions without stoichiometric reductants or dissolving metals. This mild strategy enables the chemoselective reduction and hydrofunctionalization of styrenes to furnish valuable alkane and tertiary alcohol derivatives. Mechanistic studies support the formation of a styrene olefinic radical anion intermediate and a Birch-type reduction involving two sequential single electron transfers. Overall, this complementary mode of olefin activation achieves the hydrofunctionalization of less activated alkenes with electrophiles, adding value to abundant olefins as valuable building blocks in modern synthetic protocols.
