Arenediazonium salts generated in situ from anilines have been found for the first time to efficiently oxidize [AuCl(L)] (L = SMe2, PPh3) complexes in DMSO as a solvent, under thermal conditions. The structure of the [AuArCl2(L)] complexes formed has been confirmed by X-ray diffraction analyses. These complexes have been used as intermediates, in a one pot cross-coupling reaction of anilines with silver acetylides.

In recent years interestint he development of protocols that facilitate the oxidativea ddition of gold to access mild cross-coupling processes mediated by this metal hasincreased. In this context, we report herein that ascorbic acid, an atural and readily accessible antioxidant, can be used to accelerate the oxidative addition of aryldiazonium chlorides onto Au I .T he aryl-Au III speciesg enerated in this way,h as been used to prepare 3-arylindoles in ao ne-pot protocol startingf rom anilines and para-, meta-, and ortho-s ubstituted aryldiazonium chlorides. The mechanism underlying the oxidative addition has been examined in detail based on EPR analyses, cyclic voltammetry,a nd DFT calculations. Interestingly, we have found that in this protocol, the chloride atom induces the Au II /Au III oxidation step.

Ascorbic acid, a natural reducing agent, accelerates the oxidative addition of gold to aryldiazonium chlorides. The generated arylgold(III) intermediates are used to prepared 3‐aryldindoles. The mechanism underlying the oxidative addition is examined by EPR, electrochemical studies, and DFT calculations. Interestingly, it involves a double single oxidation mechanism, where the chloride anion plays an important role. The cover artwork was designed by Hortensia Segura Silva. More information can be found in the Full Paper by S. Porcel et al. on page 634.