tert-Butyl hydroperoxide Property

Melting point:

-2.8 °C

Boiling point:

37 °C (15 mmHg)

Density 

0.937 g/mL at 20 °C

vapor pressure 

62 mmHg at 45 °C

refractive index 

n20/D 1.403

Flash point:

85 °F

storage temp. 

2-8°C

pka

pK1: 12.80 (25°C)

form 

Liquid

color 

Clear colorless

Water Solubility 

Miscible

Merck 

14,1570

BRN 

1098280

Exposure limits

No exposure limit is set. On the basis of its irritant properties a ceiling limit of 1.2 mg/m³ (0.3 ppm) is recommended.

Stability:

Stable, but may explode if heated under confinement. Decomposition may be accelerated by traces of metals, molecular sieve or other contaminants. Incompatible with reducing agents, combustible material, acids.

InChIKey

CIHOLLKRGTVIJN-UHFFFAOYSA-N

LogP

1.230 (est)

CAS DataBase Reference

75-91-2(CAS DataBase Reference)

NIST Chemistry Reference

Tert-butyl hydroperoxide(75-91-2)

EPA Substance Registry System

tert-Butyl hydroperoxide (75-91-2)

Safety

Hazard Codes 

O,C,N,T

Risk Statements 

7-10-20/21/22-34-65-52/53-43-67-53-68-51/53-23-21/22

Safety Statements 

14-3/7-61-45-36/37/39-24-17-16-14A-26-62-47-43

RIDADR 

UN 3109 5.2

WGK Germany 

3

RTECS 

EQ4900000

F 

3-21

Autoignition Temperature

Self-accelerating decomposition at 88 to 93 °C

TSCA 

Yes

HazardClass 

5.2

PackingGroup 

II

HS Code 

29094990

Hazardous Substances Data

75-91-2(Hazardous Substances Data)

Toxicity

LD50 oral (rat) 406 mg/kg
LD50 skin (rabbit) 460 mg/kg
LC50 inhal (rat) 500 ppm (4 h)

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Danger

Hazard statements

H226Flammable liquid and vapour

H242Heating may cause a fire

H300Fatal if swallowed

H302Harmful if swallowed

H304May be fatal if swallowed and enters airways

H310Fatal in contact with skin

H311Toxic in contact with skin

H314Causes severe skin burns and eye damage

H317May cause an allergic skin reaction

H318Causes serious eye damage

H330Fatal if inhaled

H336May cause drowsiness or dizziness

H341Suspected of causing genetic defects

H371May cause damage to organs

H372Causes damage to organs through prolonged or repeated exposure

H373May cause damage to organs through prolonged or repeated exposure

H410Very toxic to aquatic life with long lasting effects

H411Toxic to aquatic life with long lasting effects

Precautionary statements

P201Obtain special instructions before use.

P202Do not handle until all safety precautions have been read and understood.

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P220Keep/Store away from clothing/…/combustible materials.

P233Keep container tightly closed.

P234Keep only in original container.

P240Ground/bond container and receiving equipment.

P260Do not breathe dust/fume/gas/mist/vapours/spray.

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P270Do not eat, drink or smoke when using this product.

P271Use only outdoors or in a well-ventilated area.

P272Contaminated work clothing should not be allowed out of the workplace.

P273Avoid release to the environment.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P284Wear respiratory protection.

P301+P310IF SWALLOWED: Immediately call a POISON CENTER or doctor/physician.

P303+P361+P353IF ON SKIN (or hair): Remove/Take off Immediately all contaminated clothing. Rinse SKIN with water/shower.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P310Immediately call a POISON CENTER or doctor/physician.

P320Specific treatment is urgent (see … on this label).

P331Do NOT induce vomiting.

P403+P233Store in a well-ventilated place. Keep container tightly closed.

P405Store locked up.

P410Protect from sunlight.

tert-Butyl hydroperoxide Chemical Properties,Usage,Production

Chemical Properties

tert-Butyl hydroperoxide (TBHP) is a water-white liquid commonly commercially available as a 70% solution in water; 80% solutions are also available. It is used to initiate polymerization reactions and in organic syntheses to introduce peroxy groups into the molecule.

Uses

TBHP is an intermediate in the production of propylene oxide and t-butyl alcohol from isobutane and propylene. It is primarily used as an initiator and finishing catalyst in the solution and emulsion polymerization methods for polystyrene and polyacrylates. Other uses are for the polymerization of vinyl chloride and vinyl acetate and as an oxidation and sulfonation catalyst in bleaching and deodorizing operations. It is a strong oxidant and reacts violently with combustible and reducing materials, and metallic and sulfur compounds.

Uses

tert-Butyl hydroperoxide is used as an initiator for radical polymerization and in various oxidation process such as sharpless epoxidation. It is involved in osmium catalyzed vicinal hydroxylation of olefins under alkaline conditions. Furthermore, it is used in catalytic asymmetric oxidation of sulfides to sulfoxides using binaphthol as a chiral auxiliary and in the oxidation of dibenzothiophenes. It plays an important role for the introduction of peroxy groups in organic synthesis.

Description

Tert-butyl hydroperoxide is an alkyl hydroperoxide in which the alkyl group is tert-butyl. It is widely used in a variety of oxidation processes. It has a role as an antibacterial agent and an oxidising agent.

Production Methods

TBHP is produced by the liquid-phase reaction of isobutane and molecular oxygen or by mixing equimolar amounts of t-butyl alcohol and 30–50% hydrogen peroxide. TBHP can also be prepared from t-butyl alcohol and 30% hydrogen peroxide in the presence of sulfuric acid or by oxidation of tert-butylmagnesium chloride. The manufacturing process of TBHP is in a closed system.

General Description

Watery odorless colorless liquid. Floats and mixes slowly with water.

Reactivity Profile

Most alkyl monohydroperoxides are liquid. The explosivity of the lower members (e.g., methyl hydroperoxide, or possibly, traces of the dialkyl peroxides) decreasing with increasing chain length and branching [Bretherick 2nd ed. 1979 p. 10]. Though relatively stable, explosions have been caused by distillation to dryness [Milas, JACS 1946, 68, 205] or attempted distillation at atmospheric pressure [Castrantas 1965 p. 15].

Health Hazard

tert-Butyl hydroperoxide is a strong irritant.Floyd and Stockinger (1958) observed thatdirect cutaneous application in rats did notcause immediate discomfort, but the delayedaction was severe. The symptoms were erythemaand edema within 2–3 days. Exposureto 500 mg in 24 hours produced asevere effect on rabbit skin, while a rinse of150 mg/min was severe to eyes.
It is moderately toxic; the effects aresomewhat similar to those of MEK peroxide.Symptoms from oral administration in ratswere weakness, shivering, and prostration.
LD₅₀ value, intraperitoneal (rats): 87 mg/kg
LD₅₀ value, oral (rats): 406 mg/kg.

Flammability and Explosibility

tert-Butyl hydroperoxide is a flammable liquid and a highly reactive oxidizing agent. Pure TBHP is shock sensitive and may explode on heating. Carbon dioxide or dry chemical extinguishers should be used for fires involving tert-butyl hydroperoxide.

Mechanism of action

The general mechanism of transition metal-catalyzed oxidative Mannich reactions of N, N-dialkyl anilines with tert-butyl hydroperoxide (TBHP) as the oxidant consists of a rate-determining single electron transfer (SET) that is uniform from 4-methoxy- to 4-cyano-N, N-dimethylanilines. The tert-butylperoxy radical is the major oxidant in the rate-determining SET step that is followed by competing backward SET and irreversible heterolytic cleavage of the carbon–hydrogen bond at the α-position to nitrogen. A second SET completes the conversion of N, N-dimethylaniline to an iminium ion that is subsequently trapped by the nucleophilic solvent or the oxidant prior to the formation of the Mannich adduct[1].
Tert-butyl hydroperoxide could induce oxidative stress in liver mitochondria at low concentrations. The damaging effect of low concentrations of tBHP in the course of pyruvate oxidation in isolated liver mitochondria is caused by the opening of the nonspecific Ca²⁺-dependent cyclosporin A-sensitive pore in the inner mitochondrial membrane[2].

Safety Profile

Moderately toxic by ingestion and inhalation. A severe skin and eye irritant. Mutation data reported. At highest dosage levels, symptoms noted were severe depression, incoordmation, and cyanosis. Death was due to respiratory arrest. Very dangerous fire hazard when exposed to heat or flame, or by spontaneous chemical reaction such as with reducing materials. Moderately explosive; may explode during distillation. Violent reaction with traces of acid. Concentrated solutions may ignite spontaneously on contact with molecular sieve. Mixtures with transition metal salts may react vigorously and release oxygen. Forms an unstable solution with 1,2-dichloroethane. To fight fire, use alcohol foam, CO2, dry chemical. When heated to decomposition it emits acrid smoke and fumes.

Carcinogenicity

A study performed to evaluate the carcinogenicity of TBHP found it was not carcinogenic when applied to the skin of mice at 16.6% of the peroxide 6 times a week for 45 weeks. However, if its application was preceded by 0.05 mg of 4-nitroquinoline-1-oxide as a 0.25% solution in benzene applied 20 times over 7 weeks followed by TBHP (16.6% in benzene), then malignant skin tumors appeared between days 390 and 405 of the experiment . This supports the theory that peroxides are not complete carcinogens, but may act as promoters . The effects of TBHP on promotable and nonpromotable mouse epidermal cell culture lines were reported by Muehlematter et al. .

storage

tert-butyl hydroperoxide should be stored in the dark at room temperature (do not refrigerate) separately from oxidizable compounds, flammable substances, and acids. Reactions involving this substance should be carried out behind a safety shield.

Toxicity evaluation

TBHP accelerates oxidation of glutathione and decreases the metabolism of sodium hexobarbital in rat livers and is a strong oxidation agent.

Incompatibilities

tert-Butyl hydroperoxide and concentrated aqueous solutions of TBHP react violently with traces of acid and the salts of certain metals, including, in particular, manganese, iron, and cobalt. Mixing anhydrous tert-butyl hydroperoxide with organic and readily oxidized substances can cause ignition and explosion. TBHP can initiate polymerization of certain olefins.

Waste Disposal

Excess tert-butyl hydroperoxide and waste material containing this substance should be placed in an appropriate container, clearly labeled, and handled according to your institution's waste disposal guidelines.

References

[1] Maxim O, et al. Mechanistic Investigation of Oxidative Mannich Reaction with tert-Butyl Hydroperoxide. The Role of Transition Metal Salt. Journal of the American Chemical Society, 2013; 135: 1549–1557.
[2] Fedotcheva N, et al. Mechanism of induction of oxidative stress in liver mitochondria by low concentrations of tert-butyl hydroperoxide. Biochemistry (Moscow), 2013; 78: 75–79.