In aromatic compound

In presence of one carbon-nitrogen triple bond —C—C=N In compounds with tendency to dipole formation, e.g., C=C—C=0 In aromatic compounds... 

Nucleophilic Substitution in Aromatic Compounds with Fluorinated Substituents (Russ ) Boiko, V N hv Sib Old Akad NaukSSSR 126-136 53 a c S... 

Oosterhuis WT (1974) The Electronic State of Iron in Some Natural Iron Compounds Determination by Mossbauer and ESR Spectroscopy. 20 59-99 Orchin M, Bollinger DM (1975) Hydrogen-Deuterium Exchange in Aromatic Compounds. 23 167-193... 

Although the above structures satisfy the molecular formula, double bonds do not in reality exist in aromatic compounds. Thus, aromatic rings are usually depicted by a hexagon with a circle in it. It is understood that a hydrogen is at each corner. 

Miller, J. and Yeung, H.W. (1967) Sn Mechanism In Aromatic Compounds.35. Comparative Reactivity Of Pentachloro-fluorobenzene Hexafluorobenzene And Fluorobenzene. Australian Journal of Chemistry, 20(2), 379-381. 

Orchin, M Bollinger, D.M. Hydrogen-Deuterium Exchange in Aromatic Compounds. Vol. 23, pp. 167-193. 

London, F., 1937, Quantum Theory of Interatomic Currents in Aromatic Compounds , J. Phys. Radium, 8,397. Lowdin, P.-O., 1959, Correlation Problem in Many-Electron Quantum Mechanics , Adv. Chem. Phys., 2, 207. 

The requirements necessary for the occurrence of aromatic stabilisation, and character, in cyclic polyenes appear to be (a) that the molecule should be flat (to allow of cyclic overlap of p orbitals) and (b) that all the bonding orbitals should be completely filled. This latter condition is fulfilled in cyclic systems with 4n + 2n electrons (HuckeVs rule), and the arrangement that occurs by far the most commonly in aromatic compounds is when n = 1, i.e. that with 6n electrons. IO71 electrons (n = 2) are present in naphthalene [12, stabilisation energy, 255 kJ (61 kcal)mol-1], and I4n electrons (n = 3) in anthracene (13) and phenanthrene (14)—stabilisation energies, 352 and 380 kJ (84 and 91 kcal) mol- respectively ... 

Naphthalene itself is solid at ambient temperatures (m.p. 80.5°C) but is dissolved easily in aromatic compounds such as toluene (refer Table 13.1) [10,12], so that the oily mixture can be handled as a "naphthalene oil." The naphthalene oil is catalytically hydrogenated to decalin and methylcyclohexane simultaneously. Decalin and methylcyclohexane are converted into hydrogen and naphthalene oil again by dehydrogenation catalysis. From the handling viewpoint, the naphthalene oil may be deemed as a preferential and practical material for hydrogen storage and transportation. 

High selectivity is observed, and in aromatic compounds other substituents (C02R, OR, CN, halide) are not affected. Dinitro aromatics could be sequentially hydrogenated to nitroamines and diamines (105). [Some ruthenium and iron carbonyls were less effective (104)]. 

Trimethylgermyl substituents in aromatic compounds are easily removed with halogen, yielding the corresponding aryl halide, as shown in reaction 8119. Another example of phenyl group displacement was carried out with bromine as in reaction 2 (see end of Table 2)64. 

Different organic functional groups (i.e., methyl, methylene, phenyl, and the hydrogen atoms adjacent to the carbonyl carbon in aldehydes and organic add groups) absorb at different frequencies and thus can be easily identified. Similarly, different 13C environments result in different absorption characteristics. For instance, carbon atoms in aromatic compounds absorb different frequencies than do those in carbonyl groups. 

A relatively unique type of reactive metabolite is carbene, i.e., a divalent carbon, which is a proposed intermediate in the oxidation of methylene dioxy-containing compounds. A methylenedioxy group in aromatic compounds is subject to O-dealkylation, e.g., 3,4-methylenedioxyamphetamine, as shown in Figure 8.20. The process generates formic acid and the catechol metabolite as final products. However, in the course of the reaction, a... 

In toluene, the methyl protons resonate at 2.34 8 where as a methyl group attached to an acyclic alkane appears at 1.958. This is due to the greater deshielding influence of the ring current in aromatic compound as compared to the other. 

The nitro group is of high importance in organic chemistry, in particular in aromatic compounds because of its strong electron acceptor capacity. In accordance with this property, the nitro group has low-lying occupied and unoccupied orbitals, and the characteristic IPs of nitro compounds are usually found higher than 10 eV, which may lead to problems in the analysis of PE spectra. 

---