Diisobutylene, structure

With the exception of 4-(1,1,3,3-tetramethylbutyl)phenol prepared from diisobutylene, all the mutti-branched alkylphenols discussed consist of isomeric mixtures. In the pursuance of structure/property interests several studies have aimed to synthesise pure compounds. Thus by Wurtz-type methodology the reaction of the isomeric chloroanisoles with (i) alkyl iodides in ethereal solution in the presene of sodium and (ii) demethylation of the resultant alkylanisoles with aluminium bromide, a range of C5, Cg and Cg alkylanisoles has been synthesised (ref. 14). Numerous other methods are available for the synthesis of the isomeric n-, iso-, sec- and tert-alkylphenols some of which are referred to in Chapter 13. Reaction of a mixture of the appropriate alkyl chloride and 2-,... 

Of particular commercial interest, in connection with the effect of the olefin structure on the nature of the products of the Oxo reaction, is the behavior of diisobutylene. Diisobutylene is a mixture of 2,4,4-trimethyl-pentene-2 (I) and 2,4,4-trimethylpentene-l (II). Only one product results from treatment of the mixture of isomers ... 

To facilitate structure characterization, it was mandatory to minimize propagation. Thus a nonpolymerizable monomer was chosen, that is, an olefin which would undergo all the reactions of a polymerizable monomer (for example, isobutylene) except that it would not propagate. 2,4,4-Trimethyl-l-pentene (diisobutylene) was selected. This monomer is structurally closely related to isobutylene and due to its bulky substituents, it is unable to propagate. Model polymerization studies with this olefin could be viewed as polymerization without propagation . 

The alkylphenol p-tert-octyl phenol (PTOP) is the product of a branched-chain, eight-carbon-containing olefins, and phenol yielding the general structure as shown in Structure 3.13. The PTOP-based surfactants are used mainly in the same applications as PNP-based surfactants. In addition, a major use is as a surfactant in the emulsion polymerization of acrylic and vinyl polymers. Consumption of PTOP-based surfactants is believed to exceed 60 million lb per year. These surfactants are considered to be more of a specialty type because of the higher raw material cost of the diisobutylene as compared to nonene. 

A terminal epoxy ring is one case in which methylene C-H groups are influenced by the strained structure and an oxygen atom. Such epoxides, such as epichlorohydrin and 1,2-diisobutylene oxide, have a sharp absorption band at about 6060 cm (1650 nm) with a molar absorptivity of about 0.21/mol-cm. ... 

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