Synthesis of morpholine derivatives from 1,3-dienes and N -arylaminoalcohols by palladium-catalyzed sequential C–N and C–O bond formation

We developed a palladium-catalyzed oxidative coupling of 1,3-dienes with N-arylaminoalcohols to synthesize morpholine derivatives. Using a copper salt and 1,4-benzoquinone with molecular oxygen afforded high yields. DFT calculations elucidated the chemical selectivity and revealed that 1,4-benzoquinone acts as a ligand promoting reductive elimination, offering mechanistic insight into the catalytic cycle.