Domino Reactions of 1,3-Bis(silyl enol ethers) with 4-(Trialkylsilyloxy)benzopyrylium Triflates

Abstract

4-(Silyloxy)benzopyrylium triflates can be readily generated in situ by reaction of chromones with trialkylsilyl-tri­fluoromethanesulfonate. Domino reactions of silyl enol ethers with benzopyrylium triflates - derived from chromones, 3-cyanochromones and 3-formylchromones - allow an efficient synthesis of a variety of carba- and heterocycles.

• 1 Introduction

• 2 Reaction of 1,3-Bis(silyl enol ethers) with Chromones

• 3 Reaction of 1,3-Bis(silyl enol ethers) with 3-Cyanochromones

• 4 Reaction of 1,3-Bis(silyl enol ethers) with 3-Formylchromones

• 5 Conclusions

Keywords

cyclizations - domino reactions - heterocycles - pyrylium salts - silyl enol ethers

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