Benzene homologs

Specially prepared highly active Raney nickel (W-6) can also be used for hydrogenation of some benzene homologs under the same mild conditions that are used with noble metals [45]. In diphenyl selective hydrogenation of one benzene ring is possible. 

The benzannulation technique is also applicable to the benzene homologation and functionalization of annulenes, as well to a quadruple arene modification of dendritic cores. The reaction of chromium carbene functionalized l,6-methano[10]annulene 82 with 3-hexyne under standard conditions afforded a fair yield of the benzannulation product 83 after protection and oxidative work-up (Scheme 32) [75]. The chromium complex 84 evidently partly survived the oxidation conditions using Feln a syn-stereochemistry with respect to the Cr(CO)3 fragment and the methano bridge was suggested on the basis of NMR data, which is in contrast to the preferred formation of anti-annulation products bearing cydophane skeletons [75b]. 

Fraction I, known as light oil because it floats on water (sp. gr.= 0.975), contains some ammoniacal liquor from which it separates. The separated oil contains mostly hydrocarbons of the benzene homologous series, but there are also present in it some phenols, some basic compounds and some naphthalene. The acid and basic compounds may... 

Nitro-2, 4 diamino-azobenzene, above formula, red-gtn shiny ndls (from Nitrobenz or benzene homologes), mp 230° readily sol in acet, pyridine glacial AcOH si sol in ale eth (Ref 2). Kul berg Sc Ivanova (Ref 5) detd the color reaction of this compd in Mg salts... 

The MEKC behavior of surfactants of differing types versus SDS for the alkyl benzene homologous series is demonstrated in Figure 15.4. Because the data were normalized, slopes of one indicate similarity to SDS. As it can be observed from Figure 15.4, from all surfactants under consideration, only sodium deoxycholate (SDC, slope of 1.14 0.04) and LPFOS (slope of 0.696 + 0.009) exhibited distinctive behavior, despite the observations above concerning the restraints the solute set impart when phase selectivity is contrasted. The structure of SDC micellar aggregates is quite unusual being described by a helical model (78). The helix has the lateral surface covered by... 

FIGURE 15.4. Comparison of MEKC surfactants of different types versns SDS for alkyl benzene homologous series. Surfactants ( ) LPFOS, ( ) SDC, ( ) LDS, (A) SC, (O) TTAB, and (O) CTAB. Data compiled from Reference 27. 

Alkyl benzene homologous series alkyl H, methyl, ethyl. n-propyl, di-methyl, and ... 

Table VIII presents results of analytical investigations made by Bruner (Texas Co., Beacon, New York). The hydrocarbons of the Hydrocol process are predominantly olefinic, with straight-chain or singlo-branched structure and with double bonds mostly in the 1-position and not adjacent to the branching. Cyclic compounds are present as minor constituents and contain cyclic aliphatic homologs as well as benzene homologs.

Chromic acid and potassium permanganate are more powerful oxidizing agents than nitric acid they usually convert all side chains into carboxyl groups. Like benzene homologs, alkylpyridines can also be oxidized, yielding pyridinecarboxylic acids, e.g., isonicotinic acid from 4-ethylpyridine ... 

Hauffe K., Benzene and benzene homologous. Corrosion Handbook, vol. 6, Dechema. 1990. 

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