Thiazoles via Formal[4 + 1] of NaSH to (<i>Z</i>)‑Bromoisocyanoalkenes

A formal [4 + 1] addition of NaSH to bromoisocyanoalkenes provides substituted thiazoles via a versatile strategy that affords an array of 4- or 5-monosubstituted or 4,5-disubstituted thiazoles. The unique assembly is achieved by a rare S_NV_π displacement of NaSH on (<i>Z</i>)-bromoisocyanoalkenes. The versatile strategy addresses the dearth of conjugate additions to alkenes substituted with isocyanides as the sole electron-withdrawing group to provide an array of substituted thiazoles.