The development of new methodologies enabling a facile access to valuable heterocyclic frameworks still is an important subject of research. In this context, we describe a dual catalytic cycle merging C−H alkynylation of phenols and oxy‐alkynylation of the newly introduced triple bond by using a unique redox property and the carbophilic π acidity of gold. Mechanistic studies support the participation of a bimetallic gold–silver species. The one‐pot protocol offers a direct, simple, and regio‐specific approach to 3‐alkynyl benzofurans from readily available phenols. A broad range of substrates, including heterocycles, is transferred with excellent functional group tolerance. Thus, this methodology can be used for the late‐stage incorporation of benzofurans.

A highly efficient mercury-free route, providing [C^N] cyclometalated symmetric dialkynyl gold­(III) complexes with 2-(p-tolyl)­pyridine (tpy) as bidentate ligands and using alkynyllithium reagents, was developed. With 1,9-decadiyne, an unprecedented representative of a di­(bidentate) gold­(III) complex, for the first time became accessible. By using Grignard instead of the alkynyllithium reagents, we succeeded in synthesizing a range of novel monoalkynyl gold­(III) complexes in excellent yields (74–92%) and diastereoselectivity. Treating [(tpy)­Au­(CCTMS)2] with Bu4NF in THF gave a complete deprotection, and with K2CO3 in methanol, there was a selective deprotection of the TMS group trans to the pyridyl N atom, providing [(tpy)­Au­(CCH)­(CCTMS)] as the major product. This new type of cyclometalated gold­(III) complex bears two different alkynes as ancillary ligands. The further functionalization of the monoalkynyl (tpy)­gold­(III) complexes was investigated, offering a universal unprecedented and diastereoselective access to unsymmetrical dialkynyl (tpy)­gold­(III) complexes.

Multisubstituted alkenes are accessible by a gold-catalyzed acyloxyalkynylation of ynamides with ethynylbenziodoxolones (EBXs) with perfect atom-economy. The EBX reagents transfer both the carboxylate as well as the alkynyl entity. Overall, this cascade comprises the in situ generation of an alkynyl gold(III) species, a stereoselective C(sp)−C(sp 2 ) bond formation, and a C−O coupling at the alkynyl position of the ynamides. This reaction proceeds under mild conditions and accepts a wide range of substrates. A number of tetrasubstituted amide enol 2-iodobenzoates bearing different functional groups were obtained in good to excellent yields. DFT calculations explain the observed regioselectivity. The synthetic potential of the reaction was further demonstrated by a number of selected follow-up transformations.

Push-pull diaryl alkynes are dimerized in the presence of a cationic gold catalyst. The polarized structure of the applied starting materials enables the generation of a highly reactive vinyl cation intermediate in an intermolecular reaction. Trapping of the vinyl cation by a nucleophilic attack of the electron-poor aryl unit then leads to the selective formation of highly substituted naphthalenes in a single step and in complete atom economy.

Efficient synthetic approaches for the incorporation of nitrogen into polyaromatic compounds (PACs) in different patterns as stabilising moiety for π‐extended systems and modification tool for optoelectronic properties remain a challenge until today. Herein, we developed a new versatile pathway to napthyridine‐based PACs as non‐symmetric and regioisomeric pendant to pyrazine‐based PACs. A combination of a gold‐catalysed synthesis of 2‐aminoquinolines and the development of an in situ desulfonation and condensation of these precursors are the key steps of the protocol. The shape and type of attached functional groups of the PACs can be designed in a late stage of the overall synthetic procedure by the chosen anthranile and backbone of the ynamide introduced in the gold‐catalysed step. Single‐crystal X‐ray diffraction and the investigation of electronic properties of the compounds show the influence of the attached substituents. All naphthyridine‐based PACs show halochromic behaviour implying their use as highly sensitive proton sensor in non‐protic solvents.