Substituted alkylbenzenes

BENZENESULFONIC ACID DERIVATIVES As has been discussed previously, substituted -alkylbenzene-sulfonylureas often possess the property of releasing bound insulin, thus sparing the requirement for insulin injections in adult-onset diabetes. A pyrimidine moiety, interestingly, can serve as a surrogate for the urea function. 

The solid acid catalyzed adamantylation of substituted benzene derivatives was studied with the aim to achieve high para regioselectivities. Of various acidic resins, zeolite HY, sulfated zirconia, perfluorolkanesulfonic acids, and phosphotungstic acid, Amberlyst XN-1010 was found to be the catalyst of choice to afford para-substituted alkylbenzenes with selectivities exceeding 70%.398 In further systematic studies with a Nafion-H-silica nanocomposite catalyst,399 and various... 

Method of Hishino, Zhu, Nagahama, and Hlrata (HZNH) The method of Hishino et al. [10] applies to mono-, di-, tri-, and tetra-substituted alkylbenzenes. Based on contributions for the groups -CH3, -CH2-, CH-, and of the... 

Nucleophile addition to styrene derivatives (e.g. 75) coordinated with Cr(CO)3 is another example of addition-electrophile trapping.23,128 Addition of reactive anions is selective at the 3-position of the styrene ligand, leading to the stabilized benzylic anion (76). The intermediate reacts with protons and a variety of carbon electrophiles to give substituted alkylbenzene ligands (in 77) (equation 52). 

As mentioned in Sec. 15.2.2, hydrogen abstraction of benzylic hydrogens by the /77i triplet state of ketones is generally efficient and offers an access to benzylic radicals. However, the method is rarely of preparative interest since benzylic and ketyl radicals couple statistically giving a mixture of bibenzyls, alcohols, and pinacols, although the initial hydrogen abstraction may show some interesting intramolecular selectivity with polymethylbenzenes and substituted alkylbenzenes [220,221]. However, in... 

Oxidation pf a substituted alkylbenzene with KMnO or Ka r Oj vea a substituted benzene acid fSection 16.10). Both primorjr and secondary alkyl groups can be oxidiiod, but tertiary groups are not aflectod. 

Scheme 1. General scheme for catalytic oxidation of substituted alkylbenzenes.

I Oxidation of a substituted alkylbenzene with KMn04 or Ka2Ct207 gives a substituted benzoic acid (Section 16.9). Both primary and secondary alkyl groups can be oxidized, but tertiary groups are not affected. 

EC>12-ECU a few longer chain and multi-substituted alkylbenzenes biphenyls, methyl naphthalenes, and some smaller PAHs. 

T-K Ranatakyla, S Toppinen, T Salmi, J Aittamaa. Investigation of the hydrogenation of some substituted alkylbenzenes in a laboratory scale trickle-bed reactor. J Chem Tech Biotechnol 67 265-275,1997. 

Photo and Radical Reactions of MA 201 Table 6.8. Reaction of Maleic Anhydride with Substituted Alkylbenzenes" ... 

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