Gas chromatographic identification of chlorination products of aliphatic ketones
Igor G Zenkevich1, Eugene V Eliseenkov, Alexander N Kasatochkin
1St. Petersburg State University, Chemical Department, Universitetskii Prosp., St. Petersburg 198504, Russia. izenkevich@mail15.com
Abstract:
Chlorinated derivatives of aliphatic ketones are a class of organic compounds poorly characterized by both mass spectra and chromatographic retention indices up to present. It is caused by objective difficulties of isolation of individual products from reaction mixtures formed in the result of non-selective chlorination of parent carbonyl compounds. Nevertheless the differences of GC retention indices for structurally analogous chlorination products of different ketones and initial substrates indicate the constancy depending on the number and position of chlorine atoms in the molecules. This feature permits us to use the simplest kind of additive schemes in identification of such chlorinated derivatives, including diastereomeric α,α'-dichloro-k-alkanones (k>2). Hence, the identification of chlorination products of aliphatic ketones becomes possible for any compounds of this class without using mass spectrometric data only in the result of accurate measurement of their GC retention indices.
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