The　anodic　oxidation　of　caffeic　acid　in　the　presence　of　acetylacetone　or　methyl　acetoacetate　in　aqueous　solution　has　been　studied　by　cyclic　voltammetry　and　controlled-potential　electrolysis　techniques.　The　result　showed　that　caffeic　acid　was　oxidized　to　the　corresponding　o-benzoquinone,　which　underwent　further　Michael-addition　with　acetylacetone　or　methyl　acetoacetate　to　produce　caffeic　acid　derivative　3,4-dihydroxy-6-(1-acetylacetone)-yl　cinnamic　acid　4a　or　3,4-dihydroxy-6-(1-acetyl-methylacetate)-yl　cinnamic　acid　4b.　(c)　2006　Cheng　Chu　Zeng.　Published　by　Elsevier　B.V.　on　behalf　of　Chinese　Chemical　Society.　All　rights　reserved.