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Efficient regio- and stereoselective ring opening of epoxides with alcohols, acetic acid and water catalyzed by ammonium decatungstocerate(IV)

Valiollah Mirkhani*, Shahram Tangestaninejad, Bahram Yadollahi and Ladan Alipanah

*Chemistry Department, Isfahan University, Isfahan 81746-73441, Iran, Email: mirkhanisci.ui.ac.ir

V. Mirkhani, S. Tangestaninejad, B. Yadollahi, L. Alipanah, Tetrahedron, 2003, 59, 8213-8218.

DOI: 10.1016/j.tet.2003.08.018


Abstract

Epoxides can be cleaved in a regio- and stereoselective manner under neutral conditions with water, alcohols and acetic acid in the presence of catalytic amounts of decatungstocerate(IV) ion, affording the corresponding diols, β-alkoxy and β-acetoxy alcohols in high yields.

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Details

The document discusses the efficient regio- and stereoselective ring opening of epoxides using ammonium decatungstocerate(IV) as a catalyst. This method allows for the conversion of epoxides to β-alkoxy and β-acetoxy alcohols in high yields when reacted with alcohols and acetic acid, respectively, under neutral conditions. In water, the catalyst facilitates the formation of diols. The study highlights the superior catalytic activity of [CeW10O36]8- compared to other polyoxometallate complexes. The reactions are performed under mild conditions, often at room temperature or reflux, and yield high selectivity and efficiency. The catalyst is reusable, maintaining high yields even after multiple uses. The document also compares the effectiveness of [CeW10O36]8- with other reagents, noting its advantages such as non-hygroscopic nature, non-toxicity, availability, stability, and ease of use. The experimental section details the procedures for the catalytic reactions, including alcoholysis, acetolysis, and hydrolysis of various epoxides. The study concludes that [CeW10O36]8- is a valuable catalyst for organic synthesis due to its high regio- and stereoselectivity, high yields, short reaction times, and cost-effectiveness.


Key Words

catalysis, ring opening, epoxides, alcohols, hydrolysis, diols, β-hydroxy ethers


ID: J72-Y2003-890