Octylphenol synthesis

The octylphenol condensate is used as an additive to lubricating oils and surface-active agents. Other uses of dimer are amination to octylamine and octyldiphenylamine, used in mbber processing hydroformylation to nonyl alcohol for phthalate production and carboxylation via Koch synthesis to yield acids in formulating paint driers (see Drying). 

For commercial octylphenol products the synthesis is usually performed with the starting material 1,1,3,3-tetramethylbutane, thus resulting in t-OPs with only a single major compound for each possible ortho, meta (minor), or para-substituted) phenyl positional isomer. High-resolution chromatograms of OPs are therefore much less complicated than those of NPs (compare Fig. 2.1.4(a)-(c)), although the presence of 11 minor constituents in parai t-octylj-phenol has been reported [126]. 

The rate constant at the interface (kA) can be obtained as the slope of the straight line by plotting A ma(l — a) (1 — y )2 versus a (Fig. 5.3). This approach was used for describing the kinetics of the synthesis of 1-phenoxyoctane from sodium phenoxide and 1-bromooctane in a microemulsion based on the non-ionic surfactant Triton X-100, which is an octylphenol ethoxylate [27]. The total interfacial area was calculated from known values of the head group area of the non-ionic surfactant. As shown in Fig. 5.3, straight lines were obtained from which the rate constants could be obtained. From the values of kA determined at the three different temperatures, an activation energy of 85 kj mol-1 was calculated. This is a typical value for an SN2 reaction, as usually determined in homogeneous reaction media. 

PROBLEM 15.5 Design a synthesis for the neutral detergent shown on the preceding page (R = Cg, n = 5), starting with p-octylphenol and ethylene oxide (review Sec. 8.8). 

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