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Publisher Summary Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are ubiquitous. Most naturally occurring fats and oils are the fatty acid esters of glycerol. Esters with low molecular weight are commonly used as fragrances and found in essential oils and pheromones. Their flexibility and low polarity is manifested in their physical properties; they tend to be less rigid (lower melting point) and more volatile (lower boiling point) than the corresponding amides. This chapter analyses the separation of esters of carboxylic acids and determines the mass spectra focusing on molecular ion and fragmentation. Accurate mass measurement data would establish the presence of oxygen, especially in the ions represented by the more intense peaks. Determination of the double-bond position in C10-C24 monounsaturated methyl or ethyl esters is also discussed. The molecular ion peaks are intense with characteristic fragment ions represented by peaks at m/z 70, 98, and 113. |
