Paternò-Büchi Reactions of Silyl Enol Ethers and Enamides

Abstract

3-(Silyloxy)oxetanes are obtained by irradiating mixtures of aromatic aldehydes and silyl enol ethers in benzene as the solvent. The reactions occur with high simple diastereoselectivity and, when R^¹ is chiral, with high facial diastereoselectivity. Under similar conditions, but in acetonitrile rather than benzene as the preferred solvent, the Paternò-Büchi reaction of N-acyl enamines (enamides) gives the corresponding protected 3-aminooxetanes. The cis-products are obtained with significant simple diastereoselectivity.

cycloadditions - heterocycles - oxetanes - Paternò-Büchi reactions - photochemistry

References

<A NAME="RZ21209SS-1">1</A>

Present address: Lummus Novolen GmbH, Gottlieb-Daimler-Str. 8, 68165 Mannheim, Germany.

<A NAME="RZ21209SS-2">2</A>

Present address: Boehringer Ingelheim Pharma, Binger Str. 173, 55216 Ingelheim, Germany.

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