1975-14-0

Usage

Structure

Six-membered ring with a double bond and a ketone group

Substitution

Two 2,4,6-tris(1,1-dimethylethyl)phenyl substituents

Common use

Sterically hindered phenols in antioxidant applications

Potential applications

Materials science and polymer chemistry

Functionality

Multi-functional, providing protection against oxidative and thermal degradation.

Upstream product

• 732-26-3 2,4,6-tri-tert-butylphenoxol 
• 3315-32-0 2,4,6-tri-tert-butylphenoxyl 
• 107940-81-8 2--1H-isoindol-1,3(2H)-dion 
• 107940-82-9 2-<4-Chlorphenyl(1,3,5-tri-tert-butyl-4-oxo-2,5-cyclohexadien-1-yl)amino>-1H-isoindol-1,3(2H)-dion 
• 107940-84-1 2-<4-Methoxyphenyl(1,3,5-tri-tert-butyl-4-oxo-2,5-cyclohexadien-1-yl)amino>-1H-isoindol-1,3(2H)-dion 
• 107940-83-0 2-<4-Nitrophenyl(1,3,5-tri-tert-butyl-4-oxo-2,5-cyclohexadien-1-yl)amino>-1H-isoindol-1,3(2H)-dion 
• 156304-69-7 4-n-Butyl-4-(1,3,5-tri-tert-butyl-4-oxo-cyclohexa-2,5-dien-1-yl)-1,2-diphenyl-pyrazolidin-3,5-dion 
• 101-38-2 2,6-dichloroquinone-4-chloroimide 
• 1988-75-6 4-bromo-2,4,6-tri-tert-butyl-2,5-cyclohexadiene-1-one 
• 33919-05-0 2,4,6-tri-tert-butyl-4-hydroperoxycyclohexa-2,5-dienone 
• 67-56-1 methanol 
• 75-91-2 tert.-butylhydroperoxide 

Downstream Products

• 2444-28-2 2,6-di-tert-butyl-4-hydroxyphenol 
• 7330-85-0 4-tert-Butoxy-2,6-di-tert-butylphenol 
• 719-22-2 2,6-Di-tert-butyl-1,4-benzoquinone 
• 489-01-0 2,6-Di-t-butyl-4-methoxyphenol 
• 400-52-2 tert-butyl trifluoroacetate 
• 2606-99-7 2,6-di-tert-butyl-4-tert-butoxyphenoxyl 

Relevant academic research and scientific papers

Combining Structural with Functional Model Properties in Iron Synthetic Analogue Complexes for the Active Site in Rabbit Lipoxygenase

Iron complexes that model the structural and functional properties of the active iron site in rabbit lipoxygenase are described. The ligand sphere of the mononuclear pseudo-octahedral cis-(carboxylato)(hydroxo)iron(III) complex, which is completed by a tetraazamacrocyclic ligand, reproduces the first coordination shell of the active site in the enzyme. In addition, two corresponding iron(II) complexes are presented that differ in the coordination of a water molecule. In their structural and electronic properties, both the (hydroxo)iron(III) and the (aqua)iron(II) complex reflect well the only two essential states found in the enzymatic mechanism of peroxidation of polyunsaturated fatty acids. Furthermore, the ferric complex is shown to undergo hydrogen atom abstraction reactions with O-H and C-H bonds of suitable substrates, and the bond dissociation free energy of the coordinated water ligand of the ferrous complex is determined to be 72.4 kcal·mol-1. Theoretical investigations of the reactivity support a concerted proton-coupled electron transfer mechanism in close analogy to the initial step in the enzymatic mechanism. The propensity of the (hydroxo)iron(III) complex to undergo H atom abstraction reactions is the basis for its catalytic function in the aerobic peroxidation of 2,4,6-tri(tert-butyl)phenol and its role as a radical initiator in the reaction of dihydroanthracene with oxygen.

Titanium tetra-tert-butoxide-tert-butyl hydroperoxide oxidizing system: Physicochemical and chemical aspects

The reaction of titanium tetra-tert-butoxide with tert-butyl hydroperoxide (1: 2) (C6H6, 20 C) involves the steps of formation of the titanium-containing peroxide (t-BuO)3TiOOBu-t and peroxytrioxide (t-BuO)3TiOOOBu-t. The latter decomposes with the release of oxygen, often in the singlet form, and also homolytically with cleavage of both peroxy bonds. The corresponding alkoxy and peroxy radicals were identified by ESR using spin traps. The title system oxidizes organic substrates under mild conditions. Depending on the substrate structure, the active oxidant species can be titanium-containing peroxide, peroxytrioxide, and oxygen generated by the system.

Electron transfer between protonated and unprotonated phenoxyl radicals

(Chemical Equation Presented) The reaction of phenoxyl radicals with acids is investigated. 2,4,6-Tri-tert-butylphenoxyl radical (13), a persistent radical, deteriorates in MeOH/PhH in the presence of an acid yielding 4-methoxycyclohexa-2,5-dienone 18a and the parent phenol (14). The reaction is facilitated by a strong acid. Treatment of 2,6-di-tert-butyl-4-methylphenoxyl radical (2), a short-lived radical, generated by dissociation of its dimer, with an acid in MeOH provides 4-methoxycyclohexa-2,5-dienone 4 and the products from disproportionation of 2 including the parent phenol (3). A strong acid in a high concentration favors the formation of 4 while the yield of 3 is always kept high. Oxidation of the parent phenol (33) with PbO2 to generate transient 2,6-di-tert-butylphenoxyl radical (35) in AcOH/H2O containing an added acid provides eventually p-benzoquinone 39 and 4,4′-diphenoquinone 42, the product from dimerization of 35. A strong acid in a high concentration favors the formation of 39. These results suggest that a phenoxyl radical is protonated by an acid and electron transfer takes place from another phenoxyl radical to the protonated phenoxyl radical, thus generating the phenoxyl cation, which can add an oxygen nucleophile, and the phenol (eq 5). The electron transfer is a fast reaction.

Catalytic oxidation of a trialkyl-substituted phenol and aniline with biomimetic schiff base complexes

The catalytic oxidation of 2,4,6-tri-tert-butylphenol and 2,4,6-tri-tert-butylaniline with molecular oxygen and tert-butylhydroperoxide was investigated using biomimetic Mn-, Fe- and Co-complexes as catalysts. The catalytic activity and product distribution were determined and compared with those observed in the reactions of the well-known Co(salen) complex.

A New Methodology for the Bis(oxocyclohexadienyl) Peroxide Formation

Symmetrically substituted bis(4-oxocyclohexa-2,5-dienyl) peroxide 5 (R = R') as well as unsymmetrically substituted 5 (R ≠ R') can be prepared efficiently by treating 4-halogenocyclohexa-2,5-dienone 3 with 4-hydroperoxycyclohexa-2,5-dienone 4 in the presence of an appropriate positive halogen compound such as N-iodosuccinimide. Acetonitrile is a suitable solvent for the reaction. The formation of 5 is suggested to take place via electrophilic attack by the positive halogen species upon 3 generating the 4-oxocyclohexa-2,5-dienyl cation (or the phenoxy cation), followed by nucleophilic attack by 4 upon the cation. It is emphasized that some of the peroxides obtained by this means have not been prepared by the classical method, coupling of phenoxy radicals with O2.

Free Radical Reactions of N-Heterocyclic Compounds. XIII. Oxidation of Cyclic Hydrazo Compounds with 2,4,6-Tri-tert-butyl-phenoxy Radical and Reactions of Radical Combination Products

H-Heterocyclic compounds 1a,b containing the hydrazo structure were oxidized with 2,4,6-tri-tert-butyl-phenoxy radical (2).It was shown that the oxidation did not lead to the azo compounds 5a,b, but rather to radical combination products 6a,b of 2 via the intermediate hydrazyls 4a,b.The decomposition of adducts 6a,b was found to be similar to the reaction of radical combination products of aryl hydrazyls and CH-acidic compounds.The main reactions consisted of cleavage to starting radicals or elimination of isobutene forming the respective phenolic compounds 13a-c.

Mechanism of the Gibbs Reaction. 3. Indophenol Formation via Radical Electrophilic Aromatic Substitution (SREAr) on Phenols

Different products are formed, depending on the para substituent (R) when 2,6-dichlorobenzoquinone N-chloroimine (1b) reacts with the anion of the 4-substituted phenol (2).If the group R can leave as a cation (i.e., R is an electrofugal leaving group) such as H, CH2NMe2, CH2OH, etc., then the reaction yields indophenol (3), the normal Gibbs product.If the group R cannot leave as a cation such as CH3, the final product of the reaction will be type 10, 1,1-disubstituted 2,5-cyclohexadienone.If the group R is OH or NH2, then the reaction gives the corresponding benzoquinone 4 or benzoquinone imine 1 and 2,6-dichlorobenzoquinone imine (1d).In all these cases the reaction proceeds at a 1:1 stoichiometry.If, however, the group R can leave as an anion (i.e., R is a nucleofugal leaving group) such as halogen, alkoxy, or OCH2Ph, then the reaction proceeds at a 1:2 stoichiometry.In this case the reaction of a second mole of phenolate with type 26 intermediate yields the indophenol product 3 and the oxidized product of the phenol.If the two ortho positions of the phenolate are substituted then the oxidized product of the phenol will be the corresponding benzoquinone.The mechanism of the reaction has been studied by kinetic and nonkinetic (NMR) methods.It has been concluded that the first step of the mechanism is a single electron transfer (SET) from the phenolate to the benzoquinone N-chloroimine 1b which is the rate-determining process in most of the cases.In some of the nucleofugal cases the final oxidation, involving the second mole of phenolate, is the rate-determining step.For the radical reaction three different alternatives are suggested: a combination of radicals in a solvent cage (direct reaction) and two different chain reactions (chain A and chain B).Quantum chemical calculations revealed that the direct reaction and the chain A mechanisms were energetically more favored than chain B.The reaction shows an extremely large para selectivity although the substitution does follow a radical mechanism.

Barium manganate oxidation in organic synthesis: Part - V: Oxidation of phenols

Oxidation of phenols, specially the hindered phenols has been carried out with barium manganate in non-aqueous media under heterogeneous conditions and the results of these studies are described in this paper.

OXYDATION D'AMINES AROMATIQUES PRIMAIRES EN PRESENCE DU RADICAL TRITERTIOBUTYL-2,4,6 PHENOXYLE

The trapping of anilino radicals generated by a mild dehydrogenation of primary aromatic amines, at 20 deg C, in homogenous medium or in two-phase system, by 2,4,6-tritertiobutylphenoxy radical is carried out and the structures of the corresponding C-N or C-C coupling products are established by spectral data (IR, UV, RMN 1H).

Formation of Quinol Ethers using (Diacetoxyiodo)benzene

The use of (diacetoxyiodo)benzene for the oxidative coupling of a hindered phenol with aliphatic alcohols or other phenols has been investigated.