Abstract

Improved synthesis of 7,11-diarylspiro[5.5]undecane-1,9-dione via double Michael condensation of 1,5- bisaryl-1,4-pentadien-3-one with cyclohexanone was carried out in 51-96% yields for 3-12 h in CH2Cl2-H2O in the presence of phase-transfer catalyst under ultrasound irradiation. In comparison with reported methods, the main advantages of the present procedure are shorter reaction time and higher yields.

Keywords: 7,11-Diarylspiro[5.5]undecane-1, 9-dione, synthesis, ultrasound irradiation, Michael condensation, phase-transfer catalysis