A formal (5+1) annulation reaction from heterodimerization of two different isocyanides: stereoselective synthesis of 2H-benzo[b][1,4]oxazin-2-one.

A novel (5+1) annulation reaction of functionalized 2-isocyanophenyloxyacrylate and aromatic, aliphatic isocyanides has been disclosed. This domino reaction involves the unusual heterodimerization of two different isocyanides and allows for a quick access to many 2H-benzo[b][1,4]oxazin-2-one derivatives.