A copper(I)-catalyzed reaction of 2-(2-ethynylphenyl)oxirane, sulfonyl azide, with 2-isocyanoacetate

A novel and straightforward synthetic protocol for the efficient construction of 3',5'-dihydro-1H-spiro[benzo[d]oxepine-2,4'-imidazoles] through a copper(I)-catalyzed reaction between 2-(2-ethynylphenyl)oxirane, sulfonyl azide, and 2-isocyanoacetate is described.