Phenolic alkylation

Alkyl aryl ether Hydrogen halide A phenol Alkyl halide... 

The most important appHcation of metal alkoxides in reactions of the Friedel-Crafts type is that of aluminum phenoxide as a catalyst in phenol alkylation (205). Phenol is sufficientiy acidic to react with aluminum with the formation of (CgH O)2Al. Aluminum phenoxide, when dissolved in phenol, greatiy increases the acidic strength. It is beheved that, similar to alkoxoacids (206) an aluminum phenoxoacid is formed, which is a strong conjugate acid of the type HAl(OCgH )4. This acid is then the catalyticaHy active species (see Alkoxides, metal). 

Alkyl hydroperoxides can be Hquids or soHds. Those having low molecular weight are soluble in water and are explosive in the pure state. As the molecular weight increases, ie, as the active oxygen content is reduced, water solubiUty and the violence of decomposition decrease. Alkyl hydroperoxides are stronger acids than the corresponding alcohols and have acidities similar to those of phenols, Alkyl hydroperoxides can be purified through their alkali metal salts (28). 

Several methods are available to supplement the phenol alkylations described above. Primary alkylphenols can be produced using the more traditional Friedel-Crafts reaction. Thus an -butylphenol can be synthesized direcdy from a butyl haUde, phenol, and mild Lewis acid catalyst. Alternatively, butyryl chloride can be used to acylate phenol producing a butyrophenone. Reduction with hydrazine (a Wolff-Kishner reduction) generates butylphenol. 

Phenol alkylation Phenol Gaseous alkenes None... 

The purpose of this work was to increase the A3 selectivity at low conversion through a catalyst modification. Previous studies of phenol alkylation with methanol (the analogue reaction) over oxides and zeolites showed that the reaction is sensitive to acidic and basic properties of the catalysts [3-5]. It is the aim of this study to understand the dependence of catalyst structure and acidity on activity and selectivity in gas phase methylation of catechol. Different cations such as Li, K, Mg, Ca, B, incorporated into y-Al203 can markedly modify the polarisation of the lattice and consequently influence the acidic and basic properties of the surface [5-8] which control the mechanism of this reaction. 

P. E. Chaplanov, A. D. Chemikov, O. G. Mironov, G. N. Semanov, A. G. Svinukhov, A. G. Yaremenko, F. V. Linchevskij, N. A. Melnik, 1. A. Murashev, and I. S. Akhmetzhanov. Removing oils and petroleum products from water surfaces—using mixture of oxyethylated alkyl-phenol, alkyl-phosphate and fatty acid diethanolamine. Patent SU 1325816-A, 1992. 

R-OH (alcohols and phenols) Alkyl esters and half esters Enzyme... 

The present work deals with the study of the liquid phase phenol alkylation by (-butanol over the three types of catalysts derived from MWW-precursor MCM-22, MCM-36 and ITQ-2. It was assumed that by pillaring and/or delamination the contribution of acid sites located on the hemicages will increase and it could be evidenced during the alkylation of phenol by (-butanol, process involving large reaction intermediates and products which are difficult to be accommodated within sinusoidal channels. The reaction pathway involves many parallel and/or successive steps, the main reactions being O-alkylation and C-alkylation. The catalytic activity and selectivity of these materials are discussed. A general scheme of the process is proposed on the basis of the structural and acidic features of the catalysts. 

Keywords MCM-22, MCM-36, ITQ-2, phenol alkylation, adsorbed compounds 1. Introduction... 

Phenol, 13 747-756, 757. See also Phenols alkylation, 2 196—197 analytical methods for, 18 753—754 antimicrobial used in cosmetics, 7 831t from benzene, 3 620 from benzoic acid oxidation, 3 631 binary azeotrope with benzaldehyde, 3 591t... 

Phenol Alkylating agent Reaction conditions % yield... 

Phenol Alkylation with Bnlky Alkyl Groups... 

The deterioration resulting from the formation of these free radicals is lessened when antioxidants, such as hindered phenols, alkyl phosphites [(RO),P], or thioesters such as ROOCCH,CH2SCH2CHjCOOR are present ... 

The majority of preservatives are bacteriostatic rather than bacteriocidal, and consist of both acid and nonacid types. Among the acidic types are phenol, chloro-cresol, O-phenyl phenol, alkyl esters of parahydroxybenzoic acid, benzoic acid, boric acid, and sorbic acid, and their respective salts. Therefore, the pH of solution, and the pAa of the preservative need to be carefully evaluated prior to selecting a preservative for a formulation. Neutral preservatives include chlorobutanol, benzyl alcohol, and beta-phenylethyl alcohol. Under alkaline conditions, it is generally regarded that most microbial growth is significantly retarded at these pH values, which reduces the need for a preservative. 

All of the above described hydroxythiophenes and hydroxybenzo[6Jthiophenes can of course be alkylated with conventional phenolic alkylating agents to yield the corresponding alkoxy derivatives. However, many of the alkoxy derivatives can be obtained directly by ring closure reactions, and can indeed serve as sources of the hydroxy derivatives by dealkylation (Section 3.14.3.6). 

Other detergent alkylates which are gaining acceptance are benzene alkylated by pentamer and phenol alkylated by polypropylene, of which trimer is the preferred polymer. The pentadecylbenzene alkylate is sulfo-nated, while the nonylphenol alkylate is further reacted with ethylene oxide, the latter product going into the production of liquid non-ionic detergents. 

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