Alkylbenzenes alkyl cyclohexane

The lower the EACN of an oil. the higher its polarity. For instance. EACN is zero for benzene, and it is equal to the number of carbon atoms in the alkyl group of alkylbenzenes. Alkyl cyclohexanes have an EACN that is equal to the number of carbon atoms in their alkyl group augmented by 3. In other wcutLs. (he saturated cyclohexane structure accounts for three units in the EACN. w hiie the aromatic benzene ring does not count. 

In 2003, Velusamy and Punniyamurthy reported on a copper(II)-catalyzed C—H oxidation of alkylbenzenes and cyclohexane to the corresponding ketones with 30% hydrogen peroxide (Scheme 131). The reaction was catalyzed by the copper complex 192a depicted in Scheme 131 and yields were high in the case of alkylbenzenes (82-89%) whereas cyclohexanone was obtained with a low yield of 18%. Chemoselectivity was very high in every case neither aromatic oxidation nor oxidation at another position of the alkyl chain was observed. 

The EACN was found to depend on the oil molecular structure. Branching was not found to alter it significantly unless it is extensive, but cyclisation tends to cut it down definitely. EACN was found to be 3.5 for cyclohexane and (3.5 + n) for alkyl cyclohexanes with n carbon atoms in their alkyl chain benzene EACN was initially found to be close to 0 alkylbenzenes were found to have an EACN equal to the number of carbon atoms of their alkyl chain [4]. Recent findings with extremely pure surfactants tend to indicate that these results for aromatic oils might be erroneous, or at least misleading, because these solvents... 

The experimental data on the attainment of the minimum interfacial tension, i.e., the same criterion as optimum formulation for the three-phase behavior at low surfactant concentration, showed the equivalence of linear and cyclic hydrocarbons [29]. Figure 13 shows that the EACN of alkylbenzene hydrocarbons is equal to the number of carbons of their alkyl group, while the EACN of alkyl cyclohexanes is equal to the number of carbon atoms in their alkyl group plus 3. Thus it can be said that a saturated cycle with six carbons is equivalent to a three-carbon linear chain, while the benzene ring does not bring any additional lipophilicity. 

The benzylic position of an alkylbcnzene can be brominated by reaction with jV-bromosuccinimide, and the entire side chain can be degraded to a carboxyl group by oxidation with aqueous KMnCfy Although aromatic rings are less reactive than isolated alkene double bonds, they can be reduced to cyclohexanes by hydrogenation over a platinum or rhodium catalyst. In addition, aryl alkyl ketones are reduced to alkylbenzenes by hydrogenation over a platinum catalyst. 

Contrary to expectations, only an unusually small part of the diene exists in the conjugated form. Furthermore the formation of cyclohexane derivatives is noticeable. Their formation can be explained with the compounds listed on row 4 in Table 9. During the alkylation the monoolefin reacts on one side to LAB, on the other side to oligomers, and, depending on the excess of benzene, in part to the dialkylbenzenes found as byproducts in the so-called heavy alkylate (the residues of the raw alkylbenzene distillation). 

Benzene and substituted benzenes are reduced under mild conditions using [Co(C3Hs) P(OMe)3 3] as catalyst. Benzene, anisole and alkylbenzenes are converted to cyclohexanes, while alkyl benzoates give l-alkoxycarbonylcyclohexenes. ° Interesting is the fact that benzene is more easily reduced than cyclohexene because of the special affinity of the benzene ring for cobalt. 

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