Butylphenols, liquid

Di-fcrt-butylphenol, liquid-phase oxidation, over Cu"+-TSM, 39 322-324 Dicarbenes, isomerization, 30 56-57 Dicarbynes, 30 80-81... 

It was found that in the catalytic transformation of 2- and 4-t-butylphenol in the liquid phase on heterogeneous KSF and K10 montmorillonite catalysts under micro-wave and conventional conditions the microwaves affected both the rate and the selectivity of the reaction. 

As a safety precaution against EXPLOSION (in case the purification has been insufficiently thorough) at least a quarter of the total volume of ether should remain in the distilling flask when the distillation is discontinued. To minimize peroxide formation, ethers should be stored in dark bottles and, if they are liquids, they should be left in contact with type 4A Linde molecular sieves, in a cold place, over sodium amalgam. The rate of formation of peroxides depends on storage conditions and is accelerated by heat, light, air and moisture. The formation of peroxides is inhibited in the presence of diphenylamine, di-tert-butylphenol, or other antioxidant as stabilizer. 

DBU DMC DMF EC EO EOS GSS ILs MBMTBP MEA MW PC PDMS PEG PEGda PEO PMPS PO PPG PPGda PTC PTHF PTMO PVP Diazabicyclo[5.4.0] -undec-7-ene Dimethylcarbonate Dimethylform amide Ethylene carbonate Ethylene oxide, oxyethylene Equation of state Gas-saturated solution Ionic liquids 2,2,-methylene-bis(4-methyl-6-tert-butylphenol) Monoethanolamine Molecular weight Propylene carbonate Polydimethylsiloxane Polyethylene glycol Poly(ethylene glycol) diacrylate Polyethylene oxide Poly(methylphenylsiloxane) Propylene oxide Poly(propylene glycol) Poly(propylene glycol) diacrylate Phase-transfer catalyst Poly(tetrahydrofuran) Polytetramethylene oxide Polyvinyl pyrrolidone... 

The catalytic properties of mesoporous Ti-HMS and of hexagonal Ti-MCM-41 and Ti-SBA-3 mesostructures for the liquid phase oxidations of methylmethacrylate, styrene and 2,6-di-terr-butylphenol are described in Table 2. Included in the table for comparison are the conversions and selectivities obtained with microporous TS-1 as the catalyst. As expected based on pore size considerations, the conversions observed for all three substrates are substantially larger than for TS-1. But the most efficient mesoporous catalyst is Ti-HMS. 

A reactor was charged with 4-t-butylphenol (199.7 mmol) and 100 ml of toluene and then heated to reflux under nitrogen during which time roughly 20 ml of toluene were removed by distillation. The mixture was then cooled to 100°C, treated with the syringe-addition of tetraisopropyl titanate (47.43 mmol), and refluxed 30 minutes. Isopropanol was then removed by distillation at up to 90°C. Thereafter an additional 50 ml of isopropanol was distilled over at 140°C, and a dark red liquid was isolated. Upon cooling the liquid crystallized to a red solid at ambient temperature. The crystals were dried overnight at 80°C, and the product was isolated in 94.8% yield. 

Reaction calorimetry provides useful insights here even if direct enthalpy of formation measurements are absent. Liquid phase isomerization of the o- to p-tcrt-butylphenol has been shown to be exothermic hy 16.9 1.6 kJ mol [T. N. Nesterova, S. P. Verevkin, T. N. Malova and V. A. Pil shchikov, Zh. Prikl. Khim., 58, 827 (1985) Chem. Abstr., 103, 159918x (1985)] while the p- to m-isomerization in both the Uquid and gas phase is exothermic by ca 1 kJ mol [cf. V. A. Pil shchikov, T. N. Nesterova and A. M. Rozhnov, J. Appl. Chem. USSR, 54, 1765... 

DTBP (2,4-di-tert-butylphenol) in ionic liquids. Moreover, the selectivity to 2,4-DTBP was increased from 29.7% to 64.9%. For the HPW/MCM-41-catalyzed alkylation reactions, the improvement in effects of ionic liquids was also observed. 

In this paper we describe the preparation, characterization and the catalytic properties of polymer stabilized Rh particles for hydrogenation of 4-fert-butylphenol. The combination of TEM, XAFS and a newly developed liquid phase hydrogen/oxygen titration technique is applied to characterize particle size and availability for the reactants. 

These results show an apparent activation energy for the hydrogenation of 4-t-butylphenol of 15kJ/mol, which indicates that the reaction is controlled by liquid/solid mass transfer. 

D. Y. Murzin, A. I. Allachverdiev, N. V. Kul kova. Kinetics of liquid phase stereoselective hydrogenation of 4-tert-butylphenol over rhodium catalysts. In Heterogeneous Catalysis and Fine Chemicals III. Elsevier 1993, pp 243-250... 

D. Y. Murzin. Liquid phase hydrog iation of 4-tert-butylphenol I. The kinetic model. Kinetics and Catalysis 34 (3) 437-441,1993... 

DIBUTYLPHENOL or 2,6-DI-/rrt-BUTYLPHENOL (26746-38-3) Combustible solid or liquid above 97°F/33°C (flash point >200 F/>93°C). Reacts with oxidizers, with a risk of fire or explosions. Reacts with boranes, alkalis, aliphatic amines, amides, nitric acid, sulfuric acid. 

Let us now return to the question How to interpret or explain the fact that some reactions are affected by microwaves and some reactions are not . A detailed study of this subject has been performed by Hajek et al. [75-77] for heterogeneous catalytic liquid-phase reactions. Transformation of 2-t-butylphenol into phenol, 4-t-butylphenol, 2,4-di-t-butylphenol, and isobutene on montmorillonites as catalysts (KSF, KIO) was chosen as model reaction. Scheme 13.13. Both reactant and catalysts coupled very well with microwaves. KSF and KIO catalysts in the form of a fine powder (10-15 pm) were used to avoid creation of macroscopic hot spots (as in the presence of voluminous catalyst pellets, e.g. 5 mm [46, 47]). The results are summarized below. 

Likewise, the series of fluorous (dichloroiodo)arenes 127-129 and alkyl iodine(III) dichlorides 130-132 (Figure 5.7) have been prepared in 71-98% yields by reactions of the corresponding fluorous iodides with chlorine [69]. These compounds are effective reagents for the chlorination of alkenes (e.g., cyclooctene) and aromatic compounds (e.g., anisole, 4-rcrt-butylphenol and acetophenone). The organic chlorinated products and fluorous iodide co-products are easily separated by organic/fluorous liquid/liquid biphasic workups. The fluorous iodides can be recovered in 90-97% yields and reoxidized with chlorine [69]. 

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