75-91-2

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

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].

Water soluble.

Moderate fire risk. Oxidizer.

tert-Butyl hydroperoxide (TBHP) is an organic peroxide widely used in a variety of oxidation processes.

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. TBHP vapor can burn in the absence of air and may be flammable at either elevated temperature or at reduced pressure. Fine mist/spray may be combustible at temperatures below the normal flash point. When evaporated, the residual liquid will concentrate TBHP content and may reach an explosive concentration (＞90%). Closed containers may generate internal pressure through the degradation of TBHP to oxygen . TBHP is a highly reactive product. The three types of significant physical hazards are flammability, thermal, and decomposition due to contamination. To minimize these hazards, avoid exposure to heat, fire, or any condition that will concentrate the liquid material. Store away from heat, sparks, open flames, foreign contaminants, combustibles, and reducing agents. Inspect containers frequently to identify bulges or leaks (7a, 125).

Catalyst in polymerization reactions. To introduce peroxy group into org molecules, in radical substitution reactions: Kharasch, Fono, J. organic. Chem. 23, 325 (1948); see also Kharasch, Sosnovsky, Tetrahedron 3, 97, 105 (1958).

It is used to initiate polymerization reactionsand in organic syntheses to introduce peroxygroups into the molecule.

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.

ChEBI: An alkyl hydroperoxide in which the alkyl group is tert-butyl. It is widely used in a variety of oxidation processes.

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.

Moderately toxic by inhalation and ingestion and severely irritating to the eyes an skin. t-Butyl hydroperoxide has not been found to be carcinogenic or to show reproductive or developmental toxicity in huma

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.

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.

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.

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].

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. .

TBHP may be released to the environment through various waste streams. Chemical degradation is expected to be the dominant fate process in water because of reaction with organic matter, and, therefore, it is doubtful that unreacted TBHP would be biologically available. TBHP is expected to have high mobility in soil. If released to air, TBHP will exist solely as a vapor in the ambient atmosphere. In aqueous environments, TBHP is not expected to adsorb to sediment or suspended solids, and volatilization is expected to be the primary fate process. The half-lives for this compound in a variety of media allow for some moderate long-range transport, but not incredible distances.
An estimated bioconcentration factor (BCF) of 3 was calculated for TBHP Syracuse Research Corporation (SRC), using an estimated log Kow of 0.94 and a regression-derived equation. According to a classification scheme, this BCF suggests the potential for bioconcentration in aquatic organisms is low.

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.

Care should be taken when handling this peroxide because of the possibility of EXPLOSION. It explodes when heated over an open flame. Alcoholic and volatile impurities can be removed by prolonged refluxing at 40o under reduced pressure, or by steam distillation. For example, Bartlett, Benzing and Pincock [J Am Chem Soc 82 1762 1960] refluxed at 30mm pressure in an azeotropic separation apparatus until two phases no longer separated, and then distilled at 41o/23mm. Pure material is stored under N2, in the dark at 0o. Crude commercial material has been added to 25% NaOH below 30o, and the crystals of the sodium salt have been collected, washed twice with *benzene and dissolved in distilled water. After adjusting the pH of the solution to 7.5 by adding solid CO2, the peroxide is extracted into pet ether, from which, after drying with K2CO3, it is recovered by distilling off the solvent under reduced pressure at room temperature [O'Brien et al. J Am Chem Soc 79 6238 1957]. The temperatures should be kept below 75o . It has also been distilled through a helices packed column (ca 15 plates) and the material with b 34-35o/20mm was collected. Similarly, a solution in pet ether has been extracted with cold aqueous NaOH, and the hydroperoxide has been regenerated by adding at 0o, KHSO4 at a pH not higher than 4.5, then extracted into diethyl ether, dried with MgSO4, filtered and the ether evaporated in a rotary evaporator under reduced pressure [Milac & Djokic J Am Chem Soc 84 3098 1962]. A 3M solution of TBHP in CH2Cl2 is prepared by swirling 85mL (0.61mol) of commercial TBHP (70% TBHP-30% H2O, d 0.935 ca 7.2mmol/mL) with 140mL of CH2Cl2 in a separating funnel. The milky mixture is allowed to stand until the phases separate (ca 30minutes). The organic (lower) layer (ca 200mL) containing 0.60mole of TBHP is separated from the aqueous layer (ca 21mL) and used without further drying. TBHP is assayed by iodometric titration. With 90% grade TBHP (w/w, d 0.90, ca 9.0mmole/mL) no separation of layers occurs, i.e. when TBHP (66.67mL, 0.60mole) is added to CH2Cl2 (140mL) the resulting solution (ca 200mL) should be clear. [Walling & Buckler J Am Chem Soc 77 6032 1955, Rogers & Campbell J Am Chem Soc 74 4742 1952, Akashi et al. J Org Chem 43 2063 1978 state the quality of available grades, handling and compatibility for reactions, Beilstein 1 IV 1616.]

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

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.

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.

[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.