2-Acetyl-5-chloropyrrole in the volatile flavor constituents of cocoa butter

The presence of 2-acetyl-5-chloropyrrole in the volatile flavor constituents of cocoa butter was confirmed through synthesis of the authentic compound. This compound was synthesized by chlorination of 2-acetylpyrrole. The structure of the synthesized compound was established by infrared, nuclear magnetic resonance, and mass spectrometry. The identification of this compound in the volatile flavor constituents of cocoa butter was confirmed by comparing the mass spectrum and gas chromatographic retention time with those of the authentic sample. 2-Acetyl-5-chloropyrrole is the first chlorinated heterocyclic compound identified in the volatile flavor of foods.