Synthesis and Characterization of the Neutral“Digallene” Ar′GaGaAr′ and Its Reduction to Na2Ar′GaGaAr′ (Ar′=2,6-Dipp2C6H3, Dipp=2,6-iPr2C6H3)

Abstract

Eine Ga‐Ga‐Bindungsordnung wesentlich kleiner als 1 in dem „Digallen“ Ar′GaGaAr′ (Ar′=2,6‐Dipp2C6H3, Dipp=2,6‐iPr2C6H3; siehe Struktur) – darauf lassen Struktur und Verhalten in Lösung schließen.

Tetrahedral homonuclear organoelement clusters and subhalides of aluminium, gallium and indium

“…(1) The treatment of tetrahalogenosubhalides of the type X 2 (L)E-E(L)X 2 still containing an E-E single bond with aryl or silyl alkali metal compounds in molar ratios of 1:1 or 1:2 gave organosubhalides in moderate to sufficient yields (Kehrwald et al 2001;Klemp et al 2000b;Linti and Köstler 1996;Cowley et al 1996); (2) The reduction of a silylgallium(III) chloride [silyl=Si(CMe 3 ) 3 ] with alkali metals yielded a disilyldigallium(II) subhalide as an intermediate on the way to the formation of a tetrahedral Ga 4 cluster (Wiberg et al 2002); (3) Disproportionation in the course of the reaction of GaBr or "GaI" (see above) with aryl or silyl alkali metal derivatives gave the corresponding subhalides which, however, in many cases were isolated in low yields only in the presence of several other products, such as clusters of higher nuclearity (Kehrwald et al 2001;Hardman et al 2002Hardman et al , 2003; (4) The dilithium salt of diisopropyl aminoborole was used for the reduction of an organoindium(III) dichloride (Lomelí et al 1998). The structures of these subhalides may be described as three different types, which in part were also observed for the compounds derived from the clusters.…”

Synthesis, Structure and Chemistry of Mono‐ and Digallane Complexes Supported by N,O‐Ketimine Ligand

“…Isolation of low‐valent gallium(I) carbene analogue from the reaction of ‘‘GaI’’with lithiated β ‐diketimine by Power and co‐workers, encouraged us to perform the reaction of 1 with ‘‘GaI’’ to generate N,O ‐coordinated low‐valent Ga(I) complex. As shown in Scheme , to our surprise, the reaction led to the isolation of a stable heteroleptic digallane(II) complex [OCMeCHCMeN‐(Dipp)] 2 Ga 2 I 2 , 4 .…”

“…The Ga−Ga bond distance of 2.4002(4) Å is significantly shorter as compared to reported digallane complexes. For example, as shown in Figure , ArGa(I)‐Ga(I)Ar ( I ) (2.492(2) Å) (Ar=2,6‐Dipp 2 C 6 H 3 ), [(Me 3 Si) 2 C(Ph)C(Me 3 Si)N] 2 Ga 2 Cl 2 ( II ) (2.445(9) Å), [(L Et ) • −ClGa‐GaCl(L Et ) • −] ( III ) (2.444(1) Å) (L=[(2, 6‐ i Pr 2 C 6 H 3 )NC(Me)] 2 ) and [(ArN(X)C(Ar)N) 2 Ga 2 I] 2 ( IV ) (2.430(1) Å when X=Me; 2.4304(10) Å when X=H). In an attempt to generate low‐valent Ga(I), [OCMeCHCMeN(Dipp)]Ga(I), compound 4 was treated with potassium that led to decomposition of the starting material.…”

“…Further, the high Wiberg Bond Index (WBI) value supports the strong interaction between the gallium centers ( IV : WBI Ga1‐Ga2 =0.881; 4 : WBI Ga1‐Ga2 =0.864; Table S4). The existence of a short Ga−Ga bond in 4 may be attributed to the presence of sterically less demanding N,O ‐ketiminate ligand that allow to interact the gallium atoms more effectively compared to other digallane compounds ,,…”

Subvalent Compounds Featuring Direct Metal–Metal Bonds: The ZnZn Bond in [Cp*2Zn2]

“…Recently it was even possible to stabilize derivatives of the parent compound HGaGaH, which features a much weaker metal–metal bond 11. Again, the parent compound HGaGaH was first generated and characterized in matrix isolation experiments 12.…”