In acetonitrile containing tetramethylammonium tetrafluoroborate, 3-chloro-2,4-pentanedione undergoes a two-electron reduction at a glassy carbon cathode to cleave the carbon-chlorine bond and form the corresponding anion, namely, 2,4-pentanedion-3-ate. This latter anion is an excellent base and immediately deprotonates another molecule of starting material to form 2,4-pentanedione and 3-chloro-2,4-pentanedion-3-ate. Once formed, 3-chloro-2,4-pentanedion-3-ate is remarkably stable and, when the potential is scanned in the positive direction, can be oxidized by a one-electron process to form an unstable dimeric species, 3-chloro-3-(3-chloro-4-oxo-2-pent-2-enyloxy)-2,4-pentanedione. In addition, 3-chloro-2,4-pentanedion-3-ate can attack a haloalkane in a nucleophilic substitution reaction to form a 3-alkyl-3-chloro-2,4-pentanedione.