2668-47-5

Usage

Physical Form

White crystalline powder

Solubility

Insoluble in water, soluble in organic solvents

Primary Function

Synthetic antioxidant

Application Industries

Food, cosmetics, plastics, rubber, personal care products, pharmaceuticals

Usage

Added to fats and oils to prevent rancidity, used as a stabilizer in plastics and rubber, serves as a preservative in personal care products and pharmaceuticals

Controversy

Subject of some controversy regarding potential health risks

Regulatory Status

Approved for use in many countries

Safety

Generally considered safe at low levels of exposure

Upstream product

• 92-69-3 4-Phenylphenol 
• 115-11-7 isobutene 
• 67-56-1 methanol 
• 24457-06-5 4-hydroxy-4-phenyl-2,6-di-t-butylcyclohexa-2,5-dienone 
• 119-98-2 2-Methyl-2-(4,8,12-trimethyltridecyl)-6-chromanol 
• 2525-38-4 2,6-di-tert-butyl-4-phenylphenoxyl 
• 3232-39-1 acetyl sulfide 
• 1076-43-3 benzene-d6 
• 955-02-2 2,6-di-tert-butyl-4-diazo-2,5-cyclohexadien-1-one 
• 128-39-2 2,6-di-tert-butylphenol 
• 732-26-3 2,4,6-tri-tert-butylphenoxol 
• 119-13-1 (+)-δ-tocopherol 
• 148-03-8 d-β-Tocopherol 
• 54-28-4 d-γ-Tocopherol 

Downstream Products

• 68757-74-4 4-methoxy-4-phenyl-2,6-di-t-butylcyclohexa-2,5-dienone 
• 82636-78-0 PChd-L-Ala-OMe 
• 74763-74-9 PChd-L-Ala-OH 
• 82636-81-5 PChd-L-Ile-OMe 
• 82636-79-1 PChd-L-Val-OEt 
• 82636-82-6 PChd-L-Ile-OEt 
• 82636-80-4 PChd-L-Leu-OEt 
• 74763-75-0 PChd-Aib-OEt 
• 74763-77-2 PChd-L-Leu-OBzl 
• 63407-20-5 2,6-Di-tert-butyl-6-hydroperoxy-4-phenyl-cyclohexa-2,4-dienone 
• 24457-06-5 4-hydroxy-4-phenyl-2,6-di-t-butylcyclohexa-2,5-dienone 
• 81056-29-3 7-tert-Butyl-2-methyl-5-phenylbenzoxazol 
• 74763-79-4 PChd-L-Pro-OBzl 
• 96670-88-1 <3,5-Di-tert.-butyl-1-phenyl-4-oxo-cyclohexadien-yl>--ether 

Relevant academic research and scientific papers

Palladium-catalyzed arylation of 2,6-Di-tert-butylphenol with aryl bromides to produce 1,1′-Biphenyl-4-ol derivatives

A sterically hindered phenol, 2,6-di-tert-butylphenol, efficiently reacts with various bromobenzenes in the presence of a palladium catalyst and a base to selectively afford the corresponding 1,1'-biphenyl-4-ol derivatives.

[Pd(Cl)2(P(NC5H10)(C6H 11)2)2] - A highly effective and extremely versatile palladium-based negishi catalyst that efficiently and reliably operates at low catalyst loadings

[Pd(Cl)2(P(NC5H10)-(C6H 11)2]2] (1) has been prepared in quantitative yield by reacting commercially available [Pd(cod)(Cl)2] (cod = cyclooctadiene) with readily prepared 1-(dicyclohexylphosphanyl)piperidine in toluene under N2 within a few minutes at room temperature. Complex 1 has proved to be an excellent Negishi catalyst, capable of quantitatively coupling a wide variety of electronically activated, non-activated, deactivated, sterically hindered, heterocyclic, and functionalized aryl bromides with various (also heterocyclic) arylzinc reagents, typically within a few minutes at 100°C in the presence of just 0.01 mol% of catalyst. Aryl bromides containing nitro, nitrile, ether, ester, hydroxy, carbonyl, and carboxyl groups, as well as acetais, lactones, amides, anilines, alkenes, carboxylic acids, acetic acids, and pyridines and pyrimidines, have been successfully used as coupling partners. Furthermore, electronic and steric variations are tolerated in both reaction partners. Experimental observations strongly indicate that a molecular mechanism is operative.

Dichloro-bis(aminophosphine) complexes of palladium: Highly convenient, reliable and extremely active suzuki-miyaura catalysts with excellent functional group tolerance

Dichloro-bis(aminophosphine) complexes are stable depot forms of palladium nanoparticles and have proved to be excellent SuzukiMiyaura catalysts. Simple modifications of the ligand (and/or the addition of water to the reaction mixture) have allowed their formation to be controlled. Dichlorobis[1- (dicyclohexylphosphany1)piperidine]palladium (3), the most active catalyst of the investigated systems, is a highly convenient, reliable, and extremely active Suzuki catalyst with excellent functional group tolerance that enables the quantitative coupling of a wide variety of activated, nonactivated, and deactivated and/or sterically hindered functionalized and heterocyclic aryl and benzyl bromides with only a slight excess (1.1-1.2 equiv) of arylboronic acid at 80°C in the presence of 0.2 mol % of the catalyst in technical grade toluene in flasks open to the air. Conversions of >95% were generally achieved within only a few minutes. The reaction protocol presented herein is universally applicable. Side-products have only rarely been detected. The catalytic activities of the aminophosphine-based systems were found to be dramatically improved compared with their phosphine analogue as a result of significantly faster palladium nanoparticle formation. The decomposition products of the catalysts are dicyclohexylphosphinate, cyclohexylphosphonate, and phosphate, which can easily be separated from the coupling products, a great advantage when compared with non-water-soluble phosphine-based systems.

Novel Reduction of 2,6-Di-t-butyl-p-quinols with Sodium Borohydride

Reduction of 2,6-di-t-butyl-p-quinols with NaBH4 results unexpectedly in the regio- and stereoselective formation of the corresponding dihydro-p-quinols.The novel reduction occurs via a quinoxyborohydride anion intermediate, which regulates the stereochemistry of the 4- and 6-positions in the products.Aromatization of the products is blocked by the t-butyl groups.

Mechanism of Antioxidant Reaction of Vitamin E. Charge Transfer and Tunneling Effect in Proton-Transfer Reaction

In order to shed light on the mechanism of proton-transfer reactions, a kinetic and ab initio study of the antioxidant action (intermolecular proton transfer) of vitamin E derivatives has been carried out.The second-order rate constants (ks's)

THE CHEMISTRY OF PENTAVALENT ORGANOBISMUTH REAGENTS. PART XI. REACTIONS WITH STERICALLY HINDERED PHENOLS.

The reactivity of BiV reagents towards very hindered phenols with tert.-butyl groups at 2 and 6 under basic conditions has been studied.Unexpected phenylation at the 4-position and, in several cases, replacement of a tert.-butyl group by phenyl have been observed.The mechanism of these unexpected reactions has been discussed.

CLEAVAGE OF THE N-PChd GROUP FROM PROTECTED AMINO ACIDS AND PEPTIDES BY CATHODIC REDUCTION

Amino acids and peptide esters protected by the PChd group can be deprotected cathodically under mild conditions.

Reactions of 4-Hidroxycyclohexa-2,5-dienones under Acidic Conditions

The 4-hydroxy-4-phenyl-2,6-di-t-butylcyclohexa-2,5-dienone (2) undergoes reaction in acidic conditions to give, inter alia, derivatives of an arene-1,2-diol.In poorly nucleophilic media, the 1,1'-biphenyl-4-ol (16) and the 5-phenyl-o-benzoquinone (37) are the main products.Isolation of the 4-(2-methylpropyl)cyclohexadienone derivatives (41) and (42) provides the first examples of intermolecular trapping of a four-carbon unit.The products are consistent with the intervention of the phenoxenium ion (44); the formation of the 2-methyl-1,3-benzodioxole (43) testifies to the intermediacy of such a powerful oxidant.Whereas the 4- phenyl-2-t-butyl-p-quinol (5) gave a complex mixture from which only the 1,1'-biphenyl-4-ol derivative (24) was isolated, the 2,6-di-isopropyl- and 2,6-dimethyl-analogues (4) and (6) afforded mainly the arene-1,3-diol derivatives (48) and (47), respectively.The 4-methyl-2,6-di-t-butyl-p-quinol (7) gave products arising from nucleophilic attack on an intermediate p-quinone methide; dimers were the major products in the absence of a good nucleophile.