2,6-Di-terf-butyl-4-methylphenol

Reed, M. Thompson, D. C. Immunochemical visualization and identification of rat liver proteins adducted by 2,6-di-terf-butyl-4-methylphenol (BHT). Chem. Res. Toxicol. 1997, 10, 1109-1117. 

By studying the reaction in the presence and absence of a radical acceptor, 2,6-di-terf-butyl-4-methylphenol, radical-induced decomposition was selectively eliminated and the separate terms in Equation K were evaluated. Using barium dibenzyl dithiophosphate the following ratio was obtained ... 

Table III also presents our data for the extraction of Group 4 phenols from aqueous solutions. The o-bromophenol was added as an internal standard when some initial recovery problems were noted for the 2,6-di-terf-butyl-4-methylphenol results for its extraction are also reported here. The three phenols show good recoveries in the traps and overall good mass recoveries. One experiment was conducted under liquid C02 extraction conditions (temperature = 30 °C and pressure = 1500 lb/in.2) in an attempt to compare the relative efficiencies of the two states of CO2 for phenol extraction. Unfortunately, the phenols showed evidence of substantial breakthrough from the trapping system. The experiment does, however, demonstrate that liquid CO2 is also a good extractant for phenols present in water at parts-per-billion concentration levels.

Figure 10.9 Chromatograms of fortified coconut oil obtained by using (a) normal-phase HPLC and (b) GPC/normal-phase HPLC. Peak identification is as follows 1 (a,b), DL-a-toco-pheryl acetate, 2 (b), 2,6-di-terf-butyl-4-methylphenol 2 (a) and 3 (b), retinyl acetate 3 (a) and 4 (b), tocol 4 (a) and 5 (b), ergocalciferol. Reprinted from Analytical Chemistry, 60, J. M. Brown-Thomas et al., Determination of fat-soluble vitamins in oil matrices by multidimensional high-performance liquid chromatography , pp. 1929-1933, copyright 1988, with permission from the American Chemical Society.

Diphenyl-3-[3-(2-phenylimidazol-l-yl)propyl]-l,2,4-triazine (70) underwent thermal intramolecular addition (with loss of nitrogen) to give the tricyclic intermediate (71) and thence (by loss of benzonitrile) 2,3-diphenyl-5,6,7,8-tetrahydro-l,5-naphthyridine (72) [substrate, antioxidant (2,6-di-terf-butyl-4-methylphenol), l,3,5-Pr 3C6H3, reflux, 3 h 92%] that could be aromatized to 2,3-diphenyl-1,5-naphthyridine (73) (l,3,5-Pr 3C6H3, reflux, air, 24h 91%) the latter product (73) was also made directly from the triazine (70) (neat substrate, Se, 330°C, 10 h 85%) analogs likewise.137,522... 

Table IV. Polymer Fraction in PVC Heated for One Hour in the Presence of Cadmium Stearate and 2,6-Di-terf-butyl-4-methylphenol...

Of all the compounds prepared in this work, these latter compounds, the ortho-linked compounds derived from dimercaptans, come the closest to realizing our objective of structures with the activity of a bisphenol and the nondiscoloring characteristics of a monocyclic phenol. For example, Table IV shows some results in cw-polybutadiene which demonstrate that a compound of the type XXVI is superior as a heat stabilizer to both 2,6-di-terf-butyl-4-methylphenol and 2,2 -methylenebis(4-methyl-6-ferf-butylphenol) in both activity and color. Screening results in cis-... 

It has been established that the decomposition of cumene hydroperoxide in the presence of thiolsulfinate occurs primarily via a polar process (1). However, a homolytic process may be involved in the conversion of the thiolsulfinate to the active peroxide decomposer. This was probed by adding the radical inhibitors /2-naphthol and 2,6-di-tert-butyl-4-methylphenol (see Figure 5). The inhibitors totally suppressed the decomposition of hydroperoxide by thiolsulfinate. In contrast to /3-naphthol and 2,6-di-terf-butyl-4-methylphenol, the addition of cyclo-hexanol had no significant effect. Similarly, the addition of methanol only reduced the decomposition of hydroperoxide by the thiolsulfinate by 1% after 186 hr. 

The solution oxidation technique allows the study of polyolefin autoxi-dation under conditions where the temperature, concentration of reactants, and rates of radical initiation can be controlled. The results should be considered as a useful prelude to any fundamental understanding of the autoxidation processes which occur in neat polymers where the effects of very high viscosity, partial crystallinity, and oxygen diffusion rates are included. The objective of our work was to determine the kinetics and stoichiometry of the inhibited autoxidation of polypropylene in solution. A relatively detailed study of the oxidation of polypropylene inhibited by 2,6-di-terf-butyl-4-methylphenol [butylated hydroxytoluene (BHT)] has been made for comparison with data obtained in polypropylene oxidations inhibited by a variety of other stabilizers which include commercial polyfunctional antioxidants. Singly hindered phenols appeared to be superior in the inhibited-solution oxidation of polypropylene, and the application of this finding to stabilization technology was investigated briefly. 

Di-terf-butyl-4-methylphenol Eastman Tenox BHT, food grade, appeared to be very pure by GLC analysis and was used directly. The other simple alkyl derivatives of phenol were obtained from the usual fine chemical sources (Eastman Organic Chemicals, Aldrich, Columbia, and K and K). All were distilled and/or recrystallized and the assigned structures were confirmed by NMR. Other commercial stabilizers were obtained from their manufacturers, recrystallized (usually from ethanol or ethanol-water), and submitted for NMR confirmation of the assigned structure and purity. 

Such polymerization can be avoided by using a catalyst composed of a Group VIII metal or a derivative thereof, e.g., platinum (as platinum black or platinized asbestos or charcoal), hydrogen hexachloroplatinate, or ruthenium chloride then the 1 1 adducts can be obtained in good yield from olefins such as styrene, acrylonitrile, and methacrylic esters with, e.g., dichloro(methyl)-silane 347-349 nevertheless it is advantageous to exclude oxygen and add a polymerization inhibitor such as te/7-butylpyrocatechol or 2,6-di-terf-butyl-4-methylphenol. 

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