Searching for a connection between the two‐electron redox behavior of Group‐14 elements and their possible use as platforms for the photoreductive elimination of chlorine, we have studied the photochemistry of [(o‐(Ph2P)C6H4)2GeIVCl2]PtIICl2 and [(o‐(Ph2P)C6H4)2ClGeIII]PtIIICl3, two newly isolated isomeric complexes. These studies show that, in the presence of a chlorine trap, both isomers convert cleanly into the platinum germyl complex [(o‐(Ph2P)C6H4)2ClGeIII]PtICl with quantum yields of 1.7 % and 3.2 % for the GeIV–PtII and GeIII–PtIII isomers, respectively. Conversion of the GeIV–PtII isomer into the platinum germyl complex is a rare example of a light‐induced transition‐metal/main‐group‐element bond‐forming process. Finally, transient‐absorption‐spectroscopy studies carried out on the GeIII–PtIII isomer point to a ligand arene–Cl. charge‐transfer complex as an intermediate.

The development of catalysts for the oxygen reduction reaction is a coveted objective of relevance to energy research. This study describes a metal-free approach to catalyzing the reduction of O2 into H2O2, based on the use of redox-active carbenium species. The most active catalysts uncovered by these studies are the bifunctional dications 1,8-bis­(xanthylium)-biphenylene ([3]2+) and 4,5-bis­(xanthylium)-9,9-dimethylxanthene ([4]2+) which promote the reaction when in the presence of decamethylferrocene and methanesulfonic acid. Electrochemical studies carried out with [4]2+ suggest the intermediacy of an organic peroxide that, upon protonation, converts back into the starting dication while also releasing H2O2. Kinetic studies point to the second protonation event as being rate-determining.

Searching for a connection between the two‐electron redox behavior of Group‐14 elements and their possible use as platforms for the photoreductive elimination of chlorine, we have studied the photochemistry of [(o‐(Ph2P)C6H4)2GeIVCl2]PtIICl2 and [(o‐(Ph2P)C6H4)2ClGeIII]PtIIICl3, two newly isolated isomeric complexes. These studies show that, in the presence of a chlorine trap, both isomers convert cleanly into the platinum germyl complex [(o‐(Ph2P)C6H4)2ClGeIII]PtICl with quantum yields of 1.7 % and 3.2 % for the GeIV–PtII and GeIII–PtIII isomers, respectively. Conversion of the GeIV–PtII isomer into the platinum germyl complex is a rare example of a light‐induced transition‐metal/main‐group‐element bond‐forming process. Finally, transient‐absorption‐spectroscopy studies carried out on the GeIII–PtIII isomer point to a ligand arene–Cl. charge‐transfer complex as an intermediate.

With the discovery of late transition metal platforms that support clean photoreductive halogen eliminations, we now describe an indazol-3-ylidene gold trichloride complex ([7] + ) decorated at the 4-position by a xanthylium unit. This orange complex features a low energy band in the visible part of the spectrum, assigned to the charge transfer excitation of the indazol-3ylidene/xanthylium donor/acceptor dyad. Green-light irradiation of this complex in the presence of a chlorine trap elicits the clean photoelimination of chlorine radicals, producing the corresponding gold(I) complex. This visible-light-induced photoreduction is very efficient, reaching quantum yields close to 10 %. A neutral analog of [7] + featuring an anthryl group rather than a xanthylium unit proved to be perfectly photostable, supporting the importance of the xanthylium-based photoredox unit present in [7] + .

To augment the fluoride binding ability of Lewis acidic stiboranes, we have synthesized and characterized a SbV derivative (PhSbF2((o‐(NH(2,6‐C6H3F2)C6H4)2, 3) featuring diarylamine groups installed in proximity to the antimony center and poised to engage Sb‐bound fluoride anions in hydrogen bonding interactions. A competition experiment between 3 and Ph3SbF2 (4) along with calculations show that the fluoride ion affinity of 3 is superior to that of 4.

As part of our interest in the photochemistry of platinum/p-block element complexes, we now report on the synthesis and photoreduction of [(Ph)((o-Ph 2 P)C 6 H 4 ) 2 GePtCl 3 ] (2-Ph), a complex featuring a tetravalent platinum center connected to a germyl ligand. When in the presence of a chlorine trap, 2-Ph undergoes a clean photolysis that affords [(Ph)((o-Ph 2 P)C 6 H 4 ) 2 GePtCl] (1-Ph) and [(Cl)((o-Ph 2 P)C 6 H 4 ) 2 GePtCl](1-Cl) as confirmed by NMR spectroscopy. While the formation of 1-Ph results from the elimination of a chlorine equivalent from 2-Ph, the formation of 1-Cl indicates chlorobenzene elimination, which was confirmed and quantified using GC-MS. These results provide a unique example of a germanium-centered light-induced reduction process resulting in the ipso-chlorination of a phenylgermanium species.

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As part of our efforts to interface late transition metals with Lewis acidic main group fragments, we have decided to investigate gold complexes bearing halogermanes as Z‐type ligands. Toward this end, we have synthesized complexes of general formula [(o‐(Ph2P)C6H4)2(Ph)(X)GeAuCl] (X = F, Cl). Experimental and computational analyses indicate the presence of an Au→Ge interaction in both cases. Chloride abstraction reactions have also been investigated. In the case of X = Cl, double chloride abstraction with AgSbF6 affords a putative dication that gradually abstracts fluoride from its counterion. This putative dication is also significantly more active as a catalyst than its monocationic analog in alkyne hydroamination reactions.