Characterization of organic compounds

Kovats, E. and A. Wehrli (1959), Gas-chromatography characterization of organic compounds. III. Calculation of the retention indexes of aliphatic, alicyclic and aromatic compounds . Helv. Chim. Acta, Vol. 42, p. 2709. 

Other than the obvious advantages of reduced fluorescence and high resolution, FT Raman is fast, safe and requires mmimal skill, making it a popular analytic tool for the characterization of organic compounds, polymers, inorganic materials and surfaces and has been employed in many biological applications [41]. 

Suitable reagents for derivatizing specific functional groups are summarized in Table 8.21. Many of the reactions and reagents are the familiar ones used in qualitative analysis for the characterization of organic compounds by physical means. Alcohols are converted to esters by reaction with an acid chloride in the presence of a base catalyst (e.g., pyridine, tertiary amine, etc). If the alcohol is to be recovered after the separation, then a derivative which is fairly easy to hydrolyze, such as p-nltrophenylcarbonate, is convenient. If the sample contains labile groups, phenylurethane derivatives can be prepared under very mild reaction conditions. Alcohols in aqueous solution can be derivatized with 3,5-dinitrobenzoyl chloride. 

Franke, M., Jandl, G, and Leinweber, P. (2006). Characterization of organic compounds in aerobic biological treated municipal solid waste and re-circulated leachates. Biodegradation 17, 473 185. 

Undoubtedly, NMR is the most informative method for characterization of organic compounds. However, it has limited application in combinatorial chemistry due to several factors. NMR is a relatively insensitive and slow method, requires homogeneous samples, and consumes quite expensive deuterated solvents. Here we will discuss the most recent developments of this method that overcome the major limitations and make NMR one of the promising techniques in combinatorial chemistry. It relates to the application of NMR, not only for analyzing compounds attached to polymer support and for monitoring reactions on a solid phase, but also as a detector for liquid chromatography (LC/NMR). For the most recent review, see [10]. 

Criddle, W. J. Elhs, G. P. Spectral and Chemical Characterization of Organic Compounds A Laboratory Handbook, 3rd ed., Wiley New York, 1990. 

Kleopfer, R.D., Fairless, B.J. (1972) Characterization of organic compounds in a municipal water supply. Environ. Sci. Technol. 6, 1036-1037. 

Infrared spectra of solutions are extensively used for identification and characterization of organic compounds. The features between 200 and 1400 cm , known as the fingerprint region, are especially useful. These are absorptions due mainly to bending modes. Although it is difficult to assign the individual bonds producing this spectrum, each compound produces a characteristic pattern which can serve to identify the molecule. Fig. 14.5 shows the IR spectra of 1-propanol... 

From this study, the overall impression arises that if the azide-containing compound is thermally stable and, of course, non-explosive, the proposed azide may be handled by any of the techniques available for the detection and characterization of organic compounds. The... 

Stahl RG, Liehr JG, Davis EM. 1984. Characterization of organic compounds in simulated rainfall runoffs from model coal piles. Arch Environ Contam Toxicol 13 179-190. 

Later DW, Lee ML, Bartle KD, Kong RC, Vassilaros L (1981) Chemical class separation and characterization of organic compounds in synthetic fuels. Anal Chem 53, 1612-1620. 

A fairly complete characterization of organic compounds in the lipid, that is, the solvent-soluble fraction of the rural continental aerosol, has been achieved by Simoneit and Mazurek (1982 Simoneit, 1984). They... 

In view of its rapidity, use of milligram quantities of samples, and application to the purity region from 98.0-99.95 mole-% DSC is a most valuable tool for characterization of organic compounds (41). For a thermally stable compound, a low-purity value, based on a satisfactory run of the instrument, is... 

Alzaga, R., Mesas, A., Ortiz, L., and Bayona, J. M., Characterization of organic compounds in soil and water affected by pyrite tailing spillage, Sci. Total Environ., 242, 167-178, 1999. 

In spite of the fact that NMR spectroscopy has been used routinely in characterization of organic compounds, no systematic studies appear on the spectral properties of the parent tricyclic rings. This is mainly due to the lack of these compounds and to the difficulty of unambiguous assignments of the resonance signals in earlier times. The H NMR spectral data of some pyrrolonaphthyridine derivatives are shown below, assignments being made on the basis of H- H correlation spectroscopy (COSY) and HETCOR spectra <93(H)(36)1945,93(H)(36)2513>. 

F Wild, Characterization of Organic Compounds, 2nd edition, Cambridge University Press, Cambridge,... 

Infrared spectroscopy is probably the most widespread analytical spectroscopic technique for identification and characterization of organic compounds. Because of this identification capability infrared spectroscopy is desirable as a detection technique for chromatographic separations. With the advent of Fourier transform infrared spectroscopy/ the speed and sensitivity of infrared detection is greatly enhanced making such applications feasible. FT-IR detection has been widely accepted as a detector for gas chromatography (GC/FT-IR) (1) and has been applied with limited success to liquid chromatography (LC/FT-IR) (2)/ and more recently to supercritical fluid chromatography (SFC/FT-IR) (3). The recent review articles cited here provide excellent introduction and references to current state-of-the-art in these areas. 

The Lovelace Inhalation Toxicology Research Institute (ITRI) has been involved with METC in a cooperative program to address basic human health risks associated with low Btu coal gasification. A portion of this research involves chemical characterization of organic compounds in gaseous, liquid and solid process and waste streams. 

Typical application (as demonstrated in chapter) Characterization of organic compounds, biological samples, semiconductors, quantitative analysis... 

UV-visible spectrophotometry UV-visible spectrophotometry can be employed for identification of pigments, especially for the characterization of organic compounds or the determination of light... 

McElvain, S. M. The Characterization of Organic Compounds, Chap. Ill, The Macmillan Company, New York, 1946. 

There are a number of experimental techniques that are useful in the identification and characterization of organic compounds. Two techniques, mass spectrometry and IR spectroscopy, were discussed in Chapters 0 and 4, respectively. Here, we will discuss another important technique, nuclear magnetic resonance (NMR) spectroscopy. 

Applications of atmospheric pressure ionization mass spectrometry (API-MS) to the study of reaction intermediates and mechanisms are reviewed. API-MS, especially ESI-MS, has provided many opportunities to intercept and characterize the key intermediates from the reaction mixtures. Combined with tandem mass spectro-metric (MS/MS) methods, this technique has been extensively used for structural characterization of organic compounds and mechanism deduction of some organic reactions. Furthermore, API-MS affords a straightforward approach to trapping and identifying short-lived intermediates. 

In this chapter, we give some examples of the use of the formation of complexes in qualitative and quantitative organic analysis. It is not surprising that the major part of these examples is in the realm of the characterization of organic compounds by the formation of colored complexes and in the realm of their quantitative analysis by absorption measurements. The formation of complexes permits not only the identification of an organic compound but also the detection of some structural moieties in unknown molecules. In brief, it permits the functional analysis. 

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