Copper(I)-catalyzed domino reactions of 2-azido sulfoximines with 1-iodoalkynes yield fused triazolyl-containing benzothiadiazine-1-oxides. The protocol features the synthesis of two fused heterocyclic rings in one step with good to excellent yields and a broad functional group tolerance. Detailed mechanistic investigations indicate that a copper π-complex initiates a cycloaddition and oxidative C-N coupling reaction sequence. The results suggest an interrupted domino process involving an iodinated triazole as a key intermediate.
Keywords: CLICK; copper catalysis; cycloaddition; domino reactions; sulfoximines; sulfur heterocycles.
© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.