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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]

Reaction of carbene-stabilized disilicon ( 1) with Fe(CO)5 gives the 1:1 adduct L:SiSi[Fe(CO)4]:L (L:=C{N(2,6-Pr i2C6H3)CH}2) ( 2) at room temperature. At raised temperature, however, 2 may react with another equivalent of Fe(CO)5 to give L:Si[μ-Fe2(CO)6](μ-CO)Si:L ( 3) through insertion of both CO and Fe2(CO)6 into the Si2 core, which represents the first experimental realization of transition metal-carbonyl-mediated cleavage of a SiSi double bond. The structures and bonding of both 2 and 3 have been investigated by spectroscopic, crystallographic, and computational methods. [ABSTRACT FROM AUTHOR]

Reaction of N-heterocyclic-carbene (NHC)-stabilized disilicon ( 1) with CuCl gave a carbene-stabilized disilicon-copper(I) chloride complex ( 2). The nature of the structure and bonding in 2 has been investigated by crystallographic, spectroscopic, and computational methods. The dynamic complexation behavior of 2 was experimentally explored by variable-temperature NMR analysis. [ABSTRACT FROM AUTHOR]

This article highlights recent efforts of this laboratory in the stabilization of highly reactive, low-oxidation-state, main-group molecules using bulky N-heterocyclic carbene ligands [L: = :C{N(2,6-Pri2C6H3)CH}2; L′: = :C{N(2,4,6-Me3C6H2)CH}2; L″: = :C{(i-Pr)NC(Me)}2]. The syntheses, structures, and computational studies of carbene-stabilized neutral diborenes [L:(H)B-B(H):L and L′:(H)B-B(H):L′], a neutral Ga6 octahedron (L″:Ga[Ga4Mes4]Ga:L″), disilicon (L:Si-Si:L), bis-silylene [L:(Cl)Si-Si(Cl):L], dipnictogens (L:E-E:L, E = P, As; L′:P-P:L′), and parent phosphinidene (L:PH) are discussed. Some of the unique challenges associated with this "carbene-stabilization" strategy are also presented. [ABSTRACT FROM AUTHOR]

Reaction of thiolate 1 with carbene-stabilized diiodo-bis-silylene (2) (in a 2:1 ratio) in THF unexpectedly gives both the first five-membered, sulfur-containing, zwitterionic silylene ring (3) via insertion of the "Si2I" unit of 2 into the olefinic C--H bond of the imidazole ring of 1 and four-membered cyclic silylene (4) via insertion of a silicon(I) atom of 2 into the Cphenyl--N bond of the carbene ligand. The parallel reaction in toluene only gives 3 as the major product. The nature of the bonding in isomeric 3 and 4 was probed by experimental and theoretical methods. [ABSTRACT FROM AUTHOR]

Reaction of carbene-stabilized disilicon L: Si=Si:L (L: = :C{N(2,6-Pri2C6H3)CH}2, 1) with BH3 · THF results in facile cleavage of the silicon-silicon double bond and the formation of two quite different "push-pull" stabilized products with borane-and carbene-coordinated silylene moieties: 2, containing a parent silylene (:SiH2); and 3, containing a unique three-membered cyclosilylene. [ABSTRACT FROM AUTHOR]