Gold(I) complexes are considered active species toward oxidative addition; current understanding indicates a different mechanism in contrast to other late transition metals, but a rational understanding of the reactivity profile is lacking. Herein, we propose that the accessibility of the gold(I) center to tri-or tetracoordination is critical in the oxidative process involving a tri-or tetra-coordinate gold(I) with the oxidizing reagent as one of the ligands as an intermediate. A computational study of the geometry of (Phen)R 3 PAu(I)NTf 2 complexes shows that the accessibility of such tricoordinate species shows a good correlation with the "trans influence" of phosphine ligands: the weak σ-donating phosphine ligands promote tricoordination of gold(I) complexes. The oxidative addition to the asymmetric tricoordinate (Phen)R 3 PAu(I)NTf 2 complexes with alkynyl hypervalent iodine reagents was built. The kinetic profile of the oxidative addition exhibits a good relationship to the Hammett substituent parameter (ρ = 3.75, R 2 = 0.934), in which the gold(I) complexes bearing less σ-donating phosphine ligands increase the rate of oxidative addition. The positive ρ indicates a high sensitivity of the oxidative addition to the trans influence. The reactivity profile of oxidative addition to a linear bis(pyridine)gold(I) complex further supports that the oxidative addition to gold(I) complexes is promoted by ligands with small trans influence.

New N-heterocyclic fluorophores are sought-after compounds for organic electronic devices. Here, we report on a straightforward synthesis to access meta/para-dipyrrolobenzenes and para-dipyrrolopyrazines in high yields using a bidirectional gold-catalyzed cyclization strategy. The versatility of our reaction protocol was showcased by preparing dipyrroloarenes with different substituents, various functional groups, and in a multitude of substitution patterns. Furthermore, we showed that the dipyrroloarenes can be post-modified by N-alkylation to improve the solubility or bromination to yield precursors for further derivatization via cross-coupling. Investigation of the photophysical properties of themostly unprecedenteddipyrroloarenes identified strong blue emitters such as the diphenyl metadipyrrolobenzene with a quantum yield of 98%. Moreover, we showed that changes in the solvent polarity or interactions with Lewis acids such as borane can be used to fine-tune the photophysical properties of the fluorophores.

New N-heterocyclic compounds for organic functional materials and their efficient syntheses are highly demanded. A surprising entropy-induced selectivity switch in the gold-catalyzed intramolecular hydroarylation of 2-ethynyl N-aryl indoles was found and its exploitation led to straightforward syntheses of indolo[1,2-a]quinolines. Experimental and computational mechanistic investigations gave insight into this uncommon selectivity phenomenon and into the special reactivity of the indolo[1,2-a]quinolines. The high functional group tolerance of this methodology enabled access to a diverse scope with high yields. In addition, bidirectional approaches, post-functionalization reactions, and π-extension of the core structure were feasible. An indepth study of the photophysical properties explored the structure-effect relationship for different derivatives and revealed a high potential of these compounds for future applications as functional materials.

The transition-metal-catalyzed cyclization of bissilylethynylated N,N'-dihydrotetraazapentacene (TIPS-TAP-H 2 ) into bissilylated cyclopenta[fg,qr]pentacenes is reported. Depending on the catalyst either none, one or two silyl groups migrate and change their positions in the formed five-membered rings. The optoelectronic properties are quite similar, whereas the packing motifs differ dramatically. Control experiments and quantum chemical calculations were performed to investigate the mechanism of the reaction and the selectivity of the silyl shift.

Herein we describe a gold‐catalyzed bidirectional synthesis of N‐heteropolycyclic compounds bearing carbazole moieties – namely π‐extended benzodicarbazoles and π‐extended indolocarbazoles. Overall, four previously unknown core structures were synthesized. This approach is convergent, modular and the gold‐catalyzed key step comprises of a cascade reaction starting from stable di‐azido compounds. The obtained molecules were fully characterized and their optical and electronic properties as well as their performance in organic thin‐film transistors generated by vacuum deposition were studied. Charge‐carrier mobilities of up to 0.3 cm2/Vs were measured.