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The introduction of the cyclopropyl group in the structure of curcuminoids is a challenge by decreased reactivity in the methylene group, due to the existence of keto-enol equilibrium in these compounds. The development of this reaction is affected by the instability of curcuminoids in basic medium. Considering the possibility of developing alkylation reactions in aqueous medium using potassium carbonate as base and tetrabutylammonium bromide as a catalyst phase transfer to facilitate interaction of the reactants it was made double alkylation of five 5 5-pentatrienonas with 1,2-dibromoethane in molar ratio 1: 1, heating the reaction mixture for 12 h at 40 °C. They were obtained five cyclopropyl derivatives in yields ranging between 22 and 32 %. All obtained compounds are colored solids; they were characterized by NMR, quantitative elemental analysis and mass spectrometry. The procedure is presented as a novel method of cyclopropanation of curcuminoids that uses water as solvent; it also facilitates product separation because of its insolubility in the reaction medium, which gives environmental and economic value. [ABSTRACT FROM AUTHOR]