Switchable Divergent Synthesis in Gold-Catalyzed Difunctionalizations of <i>o</i>-Alkynylbenzenesulfonamides with Aryldiazonium Salts
Jun Li, Hongwei Shi, Shan Zhang, Matthias Rudolph, Frank Röminger, A. Stephen K. Hashmi
Abstract
Gold-catalyzed difunctionalizations of o-alkynylbenzenesulfonamides with aryldiazonium salts are reported herein. Upon irradiation with the blue LEDs, benzosultam products were formed via aminoarylation accompanied by the release of N2. Without irradiation, aryldiazonium salts were engaged as efficient electrophiles, facilitating electrophilic deaurations of the vinyl-Au(I) intermediates, followed by tautomerization to give the N-aryl-substituted α-imino (E)-hydrazones. The regioselectivities of 6-endo-dig and 5-exo-dig cyclizations were excellent.
Topics & Concepts
ChemistryElectrophileCatalysisTautomerArylCombinatorial chemistryMedicinal chemistryOrganic chemistryAlkylCatalytic Alkyne ReactionsCatalytic C–H Functionalization MethodsAsymmetric Hydrogenation and Catalysis