DBU-Catalyzed Addition Reactions of Sulfonylimidates

Abstract

Sulfonylimidates react with various types of N-protected imines in the presence of a catalytic amount of DBU to afford β-aminosulfonylimidates in high yields and high anti-selectivities. The experimental procedure is described in detail.

Key words

addition reaction - imine - catalysis - sulfonylimidate - direct reaction

References

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4

Thorough evaporation of the solvents provided the imidate HCl salt (a solid). The solidification of imidate salt could be encouraged by keeping it under argon at -20 ˚C. The exposure to air should be avoided as this salt readily absorbs moisture to form a gum-like solid, from which it was found to be difficult to remove the starting materials.