Dehydrogenative Aza-[4+2] Cycloaddition of Amines with 1,3-Dienes via Dual Catalysis

We describe a synergistic utilization of copper catalysis and proton-transfer catalysis that enables an atom- and step-economical aza-[4 + 2] cycloaddition reaction of readily available N-arylamino carbonyl compounds with simple 1,3-dienes. The reaction proceeds smoothly under an air atmosphere and produces water as the sole side product. Whereas the amines can directly serve as the C- and N-atom donors, this operationally simple protocol provides green, rapid, and efficient access to 1,2,3,6-tetrahydropyridines with a broad scope.

Automated summary

The synergistic utilization of copper catalysis and proton-transfer catalysis allows for an atom- and step-economic aza-[4 + 2] cycloaddition reaction between N-arylamino carbonyl compounds and simple 1,3-dienes. This operationally simple protocol provides a green, rapid, and efficient access to 1,2,3,6-tetrahydropyridines with a broad scope.