Synthesis of 2H-Chromenes in Ionic Liquid Solvents

George W. Kabalka; Bollu Venkataiah; Bhaskar C. Das

doi:10.1055/s-2004-832823

LETTER

Synthesis of 2H-Chromenes in Ionic Liquid Solvents

George W. Kabalka*, Bollu Venkataiah, Bhaskar C. Das
Departments of Chemistry and Radiology, The University of Tennessee, Knoxville, TN 37996-1600, USA
Fax: +1(865)9742997; e-Mail: kabalka@utk.edu;

Abstract

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Abstract

Vinylboronic acids react with o-hydroxyaryl aldehydes in room temperature ionic liquids in the presence of secondary amines to generate 2H-chromenes.

Key Words

ionic liquid - chromenes - Petasis reaction - boronic acid - green chemistry

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References

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After extracting the product from the ionic liquid, the ionic liquid was diluted with acetone; a white solid precipitated and was removed by filtration. The acetone was evaporated under reduced pressure, and the ionic liquid was then reused.