(An) efficient cu-catalyzed three component reaction

Abstract

An Efficient Cu-catalyzed Three Component Reaction; A New Synthetic Route to N-Sulfonyl Imidates and Amides It is shown that N-sulfonyl imidates can be efficiently prepared by a three component coupling of terminal alkynes, sulfonyl azides, and alcohols using a copper catalyst in the presence of an amine base. The reaction is characterized by high selectivity, mild conditions, a wide substrate scope, and high tolerance with various functional groups. Facile transformation of imidates to amidines was also achieved with the help of sodium cyanide catalyst. Additionally, a protocol for the extremely efficient Pd-catalyzed [3,3]-sigmatropic rearrangement of allylic sulfonimidates to allylic sulfonamides has been developed. Additionally we investigated N-sulfonyl amides can be efficiently prepared by an unconventional approach of the hydrative reaction between terminal alkynes, sulfonyl azides, and water in the presence of copper catalyst and amine base under very mild conditions. The present route is quite general, and a wide range of alkynes and sulfonyl azides are readily coupled catalytically with water to furnish amides in high yields. A variety of labile functional groups are tolerated under the conditions, and the reaction is regioselective in that only terminal alkynes react while double or internal triple bonds are intact. The reaction can be readily scaled up and is also adaptable to a solid-phase procedure with high efficiency.