1384457-82-2Relevant academic research and scientific papers
Organic reactions in water or biphasic aqueous systems under sonochemical conditions. A review on catalytic effects
Cravotto, Giancarlo,Borretto, Emily,Oliverio, Manuela,Procopio, Antonio,Penoni, Andrea
, p. 2 - 9 (2015/02/19)
Catalysis in aqueous systems under sonochemical conditions has become an irreplaceable method in green synthetic chemistry after more than two decades of studies in this domain. The present review has the aim of describing the state-of-the-art with a comprehensive view of advantages and limitations as well as new potential applications. Catalytic procedures in water assisted by ultrasound and/or hydrodynamic cavitation are environmentally friendly with milder conditions, shorter reaction times and higher yields. Sonochemical processes can reduce the formation of hazardous by-products, the generation of waste and also produce energy savings. Cavitational implosion generates mechanical and chemical effects such as cleaning of catalyst surface and formation of free radicals by sonolysis of water. The present overview of sonochemical reactions in water (oxidation, bromination, aza-Michael, C-C couplings, MCR and aldol reactions) should provide useful models for furthering the progress of organic synthesis using harmless and greener sound energy.
Synthesis of 2-(1,5-diaryl-1,4-pentadien-3-ylidene)- hydrazinecarboximidamide hydrochloride catalyzed by p-dodecylbenzenesulfonic acid in aqueous media under ultrasound irradiation
Li, Ji-Tai,Du, Chao,Xu, Xiao-Ya,Chen, Guo-Fen
, p. 1033 - 1038 (2012/07/03)
Amidinohydrazone compounds are very important synthetic intermediates and can serve as versatile precursors in synthesis of many natural products and drug molecules. The use of ultrasound, p-dodecylbenzenesulfonic acid (DBSA) and water as solvent improved the synthesis of different 2-(1,5-diaryl-1,4- pentadien-3-ylidene)-hydrazinecarboximidamide hydrochlorides. The best reaction conditions for the condensation of 1,5-diphenyl-1,4-pentadien-3-one with aminoguanidine hydrochloride were as follows: 1,5-diphenyl-1,4-pentadiene-3-one (1, 1 mmol), aminoguanidine hydrochloride (1.1 mmol), DBSA (0.5 mmol), water 10 mL, reaction temperature 25-27°C, irradiation frequency 25 kHz. 2a was achieved in 94% yield within 2 h. The other seven amidinohydrazones were obtained in 84-94% yield within 2-3 h under the same conditions. Compared to the method involving catalysis by hydrochloric acid in refluxing EtOH, the advantages of present procedure are milder conditions, shorter reaction times, higher yields, and environmental friendly conditions, which make it a useful strategy for the synthesis of analogues.
