Copper-Catalyzed Three-Component Selective 1,4-Amino Oxygenation of 1,3-Dienes.

Multicomponent difunctionalization of 1,3-dienes has emerged as a promising strategy for rapid synthesis of valuable allylic compounds. Here, we report an unprecedented three-component 1,4-amino oxygenation of 1,3-dienes, enabled by copper catalysis and strong Brønsted acid. The reaction engages a novel mechanism that merges umpolung electrophilic amination via copper(I)-catalyzed formation of aminium radical cations and copper (II)-mediated carbon-oxygen bond formation with alcohols. The observed 1,4-selectivity is modulated by noncovalent interactions of aminated allylic intermediates. This method presents broad synthetic utility and offers a rapid entry to (E)-1,4-allylic amino ethers, which can be derivatized into various polyfunctional molecules with high stereocontrol.