Organic compounds, spectral information

Many types of organic compounds exhibit characteristic mass spectral behaviour, a knowledge of which is useful in the interpretation of their spectra. The following section provides an introduction to the interpretation of mass spectra of simple organic compounds but readers should consult the texts listed in the references.4 Some caution is needed in the application of this information since... 

Collette (1992) proposed a novel approach to developing and applying QSARs for the alkaline hydrolysis of carboxylic acid esters using infrared (IR) spectroscopic data. The concept is to extend QSARs to a larger and more diverse group of organic compounds by including the structural information encoded in IR spectra. Such data are available from spectral data bases, but even in the absence of literature data, IR frequencies are readily measurable. 

Following the spectral examples, a discussion section provides details about the functional groups and other information that may be of use in identifying organic compounds. You may choose to omit this section on your first reading of the material. 

Another piece of information is obtained from the relative area of the absorption peaks in the spectrum, which teUs us the relative number of protons in each group. So, a proton NMR spectmm should be examined for (1) the number of proton resonances which tells you how many different types of protons are in the molecule (2) the chemical shifts of the resonances which identifies the type of proton (3) the multiplicity of the resonances which identifies the adjacent equivalent protons and (4) the intensity (area) of the resonances which tells you the relative number of each type of proton. Some examples of common classes of organic compounds are discussed. Not every type of compound is covered in this brief overview. Students needing more detailed spectral interpretation should consult the references by SUverstein and Webster, Pavia et al., Lambert et al., or similar texts. 

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