Carbodiimides as Acid Scavengers in Aluminum Triiodide Induced Cleavage of Alkyl Aryl Ethers

Abstract

A practical procedure for the cleavage of alkyl aryl ethers containing labile functional groups has been developed using aluminum triiodide as the ether cleaving reagent. Carbodiimides, typically used as dehydration reagents for the coupling of amines and carboxylic acids to yield amide bonds, are found to be effective hydrogen iodide scavengers that prevent acid-labile groups from deterioration. The method is applicable to variant alkyl aryl ethers such as eugenol, vanillin, ortho-vanillin and methyl eugenol. Suitable substrates are not limited to alkyl o-hydroxyphenyl ethers.

Key words

acid scavenger - aluminum triiodide - carbodiimide - demethylation - ether cleavage

• References

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