Reactions of Alkylphenols

Reactions of alkylphenols producing side-chains having oxy or aikoxycarbonyl substituents. 

TABLE 6.5 REACTIONS OF ALKYLPHENOLS TO GIVE SIDE CHAINS WITH OXY,OXO,... 

The reactions of alkylphenols (containing substituents having at least three carbon atoms) with formaldehyde afford resins known as alkyl-phenolic resins [35]. Examples of suitable phenols include / /-/-butylphenol, octylphenol, and phenylphenol. 

The third family (c. in Figure 9.1) less widespread, derived from the alkylphenols, offers as with the succinimides several possibilities of modification to the ratio of hydrophilic and lipophilic groups. Mannich s reaction of the alkyl-phenols also provides additives for lubricating oils. 

Manufacture and Processing Alkylphenols of commercial importance are generally manufactured by the reaction of an alkene with phenol in the presence of an acid catalyst. The alkenes used vary from single species, such as isobutylene, to compHcated mixtures, such as propylene tetramer (dodecene). The alkene reacts with phenol to produce mono alkylphenols, dialkylphenols, and tri alkylphenols. The mono alkylphenols comprise 85% of all alkylphenol production. 

The design of these distillation systems and the operating conditions used depend on the physical properties of the alkylphenols involved and on the product requirements. Essentially all alkylphenol distillation systems operate under vacuum, but the actual pressures maintained vary considerably. Vacuum operation allows reasonable reboder temperatures (200—350°C) so that thermal dealkylation reactions of the alkylphenols are slow. 

The cleavage products of several sulfonates are utilized on an industrial scale (Fig. 3). The fusion of aromatic sulfonates with sodium hydroxide [1310-73-2J and other caustic alkalies produces phenohc salts (see Alkylphenols Phenol). Chlorinated aromatics are produced by treatment of an aromatic sulfonate with hydrochloric acid and sodium chlorate [7775-09-9J. Nitriles (qv) (see Supplement) can be produced by reaction of a sulfonate with a cyanide salt. Arenesulfonates can be converted to amines with the use of ammonia. This transformation is also rather facile using mono- and dialkylamines. 

Commercial alkylphenol ethoxylates are almost always produced by base-cataly2ed ethoxylation of alkylphenols. Because phenols are more strongly acidic than alcohols, reaction with ethylene oxide to form the monoadduct is faster. The product, therefore, does not contain unreacted phenol. Thus, the distribution of individual ethoxylates in the commercial mixture is narrower, and alkylphenol ethoxylates are more soluble in water. 

Although connection of polyalkylene or poly(alkylene oxide) groups to the polyamine is most commonly by the succinimide linkage, a different linking group is employed in another important class of ashless dispersants— the Mannich bases. They are prepared on a commercial scale by reaction of an alkylphenol with formaldehyde and a polyamine (173—177). The alkyl and polyamine moieties are similar to those used in the succinimide products. 

Other polyamine derivatives are used to break the oil/water emulsions produced at times by petroleum wells. Materials such as polyether polyols prepared by reaction of EDA with propylene and ethylene oxides (309) the products derived from various ethyleneamines reacting with isocyanate-capped polyols and quaternized with dimethyl sulfate (310) and mixtures of PEHA with oxyalkylated alkylphenol—formaldehyde resins (311) have been used. 

With Phenols. The 2-hydroxylethyl aryl ethers are prepared from the reaction of ethylene oxide with phenols at elevated temperatures and pressures (78,79). 2-Phenoxyethyl alcohol is a perfume fixative. The water-soluble alkylphenol ethers of the higher poly(ethylene glycol)s are important surface-active agents. They are made by adding ethylene oxide to the alkylphenol at ca 200°C and 200—250 kPa (>2 atm), using sodium acetate or... 

If, for the purpose of comparison of substrate reactivities, we use the method of competitive reactions we are faced with the problem of whether the reactivities in a certain series of reactants (i.e. selectivities) should be characterized by the ratio of their rates measured separately [relations (12) and (13)], or whether they should be expressed by the rates measured during simultaneous transformation of two compounds which thus compete in adsorption for the free surface of the catalyst [relations (14) and (15)]. How these two definitions of reactivity may differ from one another will be shown later by the example of competitive hydrogenation of alkylphenols (Section IV.E, p. 42). This may also be demonstrated by the classical example of hydrogenation of aromatic hydrocarbons on Raney nickel (48). In this case, the constants obtained by separate measurements of reaction rates for individual compounds lead to the reactivity order which is different from the order found on the basis of factor S, determined by the method of competitive reactions (Table II). Other examples of the change of reactivity, which may even result in the selective reaction of a strongly adsorbed reactant in competitive reactions (49, 50) have already been discussed (see p. 12). 

Fig. 8. Relationship between relative reactivities S and the ratios of the initial reaction rates rj°/VA° of alkylphenols to phenol in the hydrogenation on Ni-catalyst containing 8.4% (wt.) AUOa at 160°C and initial molar ratio of hydrogen to organic substances G = 19. Alkyl substituents in phenols Me—methyl, Et—ethyl, Pr—n-propyl, i-Pr— isopropyl, s-Bu—sec-butyl, t-Bu—terc-butyl.

Assuming that ks = k9 = 3x 108Lmol 1s 1 (the key value), the diversity of the rate constants of the reactions of phenols and phenoxyl radicals (7, —7, 10, 11, and 12) can be reduced to only two parameters, k7 and T. This allows one to get the universal formulae for the oxidation rate v, into which these parameters enter as functions of k2, k7, T, and ambient conditions (Table 14.7). When considering this table, it should be taken into account that mechanism VII is possible only for 2,4,6-tris-alkylphenols, while mechanism IX holds only for o- and p-alkoxyphenols. 

For the quantification of alkylphenol ethoxylates (APEOs), several related compounds have been used as internal standard, e.g. for recovery determination, decylphenol monoethoxylate [20]. Octylphenol nonaethoxylate (t-0PE09) was synthesised by reacting octylphenol (OP) with 1,2-6j.s(2-chloroethoxy)ethane to give the chloro derivative, followed by reaction with the sodium salt of hexaethylene glycol [21,22], Another approach used the synthetic standard l-(4,-methoxyphenyl)-hexan-l-ol as a surrogate to monitor the efficiency of the extraction for... 

The alcohol ethoxylates and alkylphenol ethoxylates are produced by the reaction of alcohol with an excess of ethylene oxide. The reaction of... 

Nitration of alkylphenols.1 p-Cresol (1) is converted into 2,6-dinitro-p-cresol in 66% yield by reaction with dinitrogen tetroxide in acetonitrile (25-30°). 

The McLafferty reaction in alkylphenols occurs stepwise The migration of a y -H to one of the ortho positions generates distonic ions 24 en route to the fragmentation products (Scheme 8). It has been shown that the relative stability of these reactive intermediates governs the competition between the McLafferty reaction and the benzylic cleavage in the El source and that its influence is more important than the relative stability of the... 

Vapor-phase alkylation of phenol with ferf-butyl alcohol in the presence of trivalent iron-substituted molecular sieve catalysts (FeMCM-41) gives para-fert-butylphenol with high regioselectivity . Supported heteropoly acid catalysts have been used in the heterogeneous alkylation reactions of 1-octene or nonene with phenol at 80-100°C. The catalyst H4SiWi204o/Si02 gives 90% para-alkylphenol and 10% orf/zo-alkylphenol. 

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