Aromatics CH deformations

The FTIR spectra of original alkyd resin and soxhlet extracted resin are shown in Figure 2 which shows the characteristic peaks of ester stretching (COOR) at 1729.49 cm, unsaturated fatty acid at 1266.23 cm and aromatic CH deformation at 730cm closely matches thus establishing that alkyd resin has been successfully encapsulated within urea-formaldehyde shell. 

Vibration Mode CH3, CH2 stretch C = 0 stretch (ester) -CH2 - deformation CH3 - N deformation C-0 stretch (ester) aromatic CH out of plane deformation (mono-substituted benzene ring)... 

Out of plane deformation aromatic CH Skeletal vibration, straight chains > 9 CH2... 

The coke formation in methanol to hydrocarbons conversion over zeolite H-MFI was also studied with UV-RS. To distinguish between the signals that correspond to CH deformations and to CC stretches, experiments were carried out with deuterated methanol (CD3OH). The bands assignments used in this study are summarized in Table 2. It is concluded that cyclopentadienyl species are intermediates in the formation of polyaromatic hydrocarbons. By comparison with pure polynuclear aromatics UV-RS spectra, it is suggested that coke... 

I5B5 and 1 90 aromatic C=C and NH2 770-710 aromatic CH out-of-plane deformation mono-substituted phenyls... 

Fig. 2 Transmission FT-IR of purified TPPT. Three spectral regions can be distinguished (i) 3150-3000 cm aromatic CH stretching vibrations, (ii) 2100-1660 cm overtone and combination bands due to the CH out-of-plane deformation vibrations, and (iii) 1600-400 cm fingerprint region...

Figure 1-18. A synchronous 2D IR spectrum in the CH deformation and aromatic ring semicircle stretching vibration region of a blend of polystyrene and low-density polyethylene at room temperature [2],...

Polymer Aromatic CH stretching Aliphatic CH stretching Ring stretching Methyl deformation Aromatic CH out-of-plane... 

Sulphonic acid esters Alkyl aryl sulphonic acid esters, such as ethyl p-toluene sulphonate, have two strong characteristic bands near 1350 cm ( 7.41 pm) and 1180cm ( 8.47pm) in their infrared spectra. Aryl esters of alkyl sulphonic acids normally have a strong absorption near 865-650cm (11.56-15.38pm) due to aromatic CH out-of-plane deformation vibrations and in this respect their spectra are similar to those of aryl sulphonamides but, of course, sulphonamides have additional bands due to their NH stretching vibrations. 

Electrophilic Substitution Reactivity Much of the electrophilic reactivity of aromatics is described in great detail in a comprehensive recent book of Taylor [10]. We shall focus attention on the electrophilic substitution reactivity of annelated benzenes and try to interpret the orientational ability of fused small rings. For this purpose we consider here Wheland transition states of the electrophilic substitution reactions. It is also convenient to take the proton as a model of the electrophilic reagent. In order to delineate rehybridization and 7r-electron localization effects, let us consider a series of angularly deformed benzenes (Fig. 21), where two vicinal CH bonds bent toward each other mimick a fused small ring. Angles c of 110° and 94° simulate five and four membered... 

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