Surfactant-Assisted Ozonolysis of Alkenes in Water: Mitigation of Frothing Using Coolade as a Low-Foaming Surfactant
Supanat Buntasana, Jun Hayashi, Prakorn Saetung, Piyatida Klumphu, Tirayut Vilaivan and Panuwat Padungros*
*Department of Chemistry, Faculty of Science, Chulalongkorn University, Phayathai Road, Pathumwan, Bangkok 10330, Thailand,
Email: panuwat.p
chula.ac.th
S. Buntasana, J. Hayashi, P. Saetung, P. Klumphu, T. Vilaivan, P. Padungros, J. Org. Chem., 2022, 87, 6525-6540.
DOI: 10.1021/acs.joc.1c02539
see article for more reactions
Abstract
The use of Coolade as a nonionic and low-foaming surfactant enables an ozonolysis of alkenes in water to provide carbonyl products in good yields. During the ozonolysis reaction, water molecules intercept the Criegee intermediate to provide a hydroxy hydroperoxide intermediate that decomposes to the carbonyl compound without the need for a reductant.
see article for more examples
proposed reaction pathway
Coolade
reactions without reductive workup (shortened table)
Details
The study explores surfactant-assisted ozonolysis of alkenes in water, inspired by atmospheric aqueous-phase ozonolysis. Traditional ozonolysis in organic solvents often requires reductants and poses safety risks. Using water as a medium mitigates these issues but faces challenges like low solubility of ozone and alkenes, and excessive foaming. The research investigates various surfactants, finding that Coolade, a nonionic and low-foaming surfactant, effectively enhances solubility and mitigates foaming. Coolade-assisted ozonolysis yields carbonyl products in good yields, comparable to those in organic solvents, without needing additional reductants. The study demonstrates that water trapped in Coolade's polyethylene glycol region intercepts the Criegee intermediate, forming hydroxy hydroperoxide, which decomposes to carbonyl products. This method is efficient for both aromatic and aliphatic alkenes, though electron-rich alkenes show lower yields due to over-oxidation. The research highlights Coolade's potential for other gas-bubbling reactions in water, promoting greener chemical processes.
Key Words
ID: J42-Y2022
