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The 1 : 2 reaction of the imidazole‐based dithiolate (2) with GeCl2 • dioxane in THF/TMEDA gives 3, a TMEDA‐complexed dithiolene‐based germylene. Compound 3 is converted to monothiolate‐complexed (5) and N‐heterocyclic carbene‐complexed (7) germanium(II) dithiolene complexes via Lewis base ligand exchange. A bis‐dithiolene‐based germylene (8), involving a 3c–4e S‐Ge‐S bond, has also been synthesized through controlled hydrolysis of 7. The bonding nature of 3, 5, and 8 was investigated by both experimental and theoretical methods. [ABSTRACT FROM AUTHOR]

A series of reactions between Lewis bases and an imidazole‐based dithione dimer (1) has been investigated. Both cyclic(alkyl)(amino)carbene (CAAC) (2) and N‐heterocyclic carbene (NHC) (4), in addition to N‐heterocyclic silylene (NHSi) (6), demonstrate the capability to cleave the sulphur–sulphur bonds in 1, giving carbene‐stabilized dithiolene (L0) zwitterions (3 and 5) and a spirocyclic silicon–dithiolene compound (7), respectively. The bonding nature of 3, 5, and 7 are probed by both experimental and theoretical methods. [ABSTRACT FROM AUTHOR]

Reaction of carbene‐stabilized disilicon (1) with the lithium‐based dithiolene radical (2.) affords the first dianionic silicon tris(dithiolene) complex (3). Notably, the formation of 3 represents the unprecedented utilization of carbene‐stabilized disilicon (1) as a silicon‐transfer agent. The nature of 3 was probed by multinuclear NMR spectroscopy, single‐crystal X‐ray diffraction, and DFT computations. [ABSTRACT FROM AUTHOR]

Abstract: Whereas low‐temperature (−78 °C) reaction of the lithium dithiolene radical 1. with boron bromide gives the dibromoboron dithiolene radical 2., the parallel reaction of 1. with (C6H11)2BCl (0 °C) affords the dicyclohexylboron dithiolene radical 3.. Radicals 2. and 3. were characterized by single‐crystal X‐ray diffraction, UV/Vis, and EPR spectroscopy. The nature of these radicals was also probed computationally. Under mild conditions, 3. undergoes unexpected thiourea‐mediated B−C bond activation to give zwitterion 4, which may be regarded as an anionic dithiolene‐modified carbene complex of the sulfenyl cation RS+ (R=cyclohexyl). [ABSTRACT FROM AUTHOR]

The first magnesium-based dithiolene, 2, was prepared by reaction of the lithium dithiolene radical, 1Ṗ, with 2-mesitylmagnesium bromide. Reaction of 2 with N-heterocyclic carbenes (in toluene) gave a carbene-stabilized magnesium monodithiolene complex, 3. Complex 3, in turn, is readily converted to a THF-solvated magnesium bis-dithiolene dianion, 4, via partial hydrolysis in polar solvents (i.e., THF/CH3CN). Compounds 2, 3 and 4 have been spectroscopically and structurally characterized and probed by DFT computations. [ABSTRACT FROM AUTHOR]

Sulfurization of anionic N-heterocyclic dicarbene, [:C{[N(2,6-Pri2C6H3)]2CHCLi}]n (2), with elemental sulfur (in a 1:2 ratio) in Et2O at low temperature gives 3 by inserting two sulfur atoms into the Li-C (i.e., C2 and C4) bonds in polymeric 2. Further reaction of 3 with 2 equiv of elemental sulfur in THF affords 4• via unexpected C-H bond activation, which represents the first anionic dithiolene radical to be structurally characterized in the solid state. Alternatively, 4• may also be synthesized directly by reaction of 1 with sulfur (in a 1:4 ratio) in THF. Reaction of 4• with GeCl2⋅dioxane gives an anionic germanium(IV)-bis(dithiolene) complex (5). The nature of the bonding in 4• and 5 was probed by experimental and theoretical methods. [ABSTRACT FROM AUTHOR]