Facile Conversion of Thioamides into the Corresponding Amides in the Presence of Tetrabutylammonium Bromide

Abstract

Desulfurization of thioamides was accomplished using a semicatalytic amount of Bu₄NBr. The corresponding amides were obtained in high yields, with good functional group compatibility.

Key words

desulfurization - thioamides - amides - tetrabutylammonium bromide - thioketones

References

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3

Indeed, only little is known about the functional-group compatibility of this kind of desulfurization process in previous reports.

5

MeCN and DMA had a yield-improving effect similar to DMF (75% and 73% yield of 2, respectively). Use of other solvents, such as 1,4-dioxane, toluene, and 2-BuOH resulted in lower yields.

8

Unfortunately, an aliphatic thioamide such as N-phenyl-thioacetamide did not undergo the desulfurization, the reaction of which resulted in the recovery of a large amount of the starting material.