How long are Ga⇆Ga double bonds and Ga–Ga single bonds in dicationic gallium dimers?

Abstract

Syntheses and characterization of two salts [(L)GaGa(L)][pf]2 ([pf]− = [Al(ORF)4]−; RF = C(CF3)3) are reported. They include the first dicationic digallene [(L)Ga⇆Ga(L)]2+ (L = CDPPh = C(PPh3)2) and a digallane...

Activation of the GaI Cation for Bond Activation: from Oxidative Additions into C−Cl and H−P Bonds to Reversible Insertion into P4

“…Crystallisation yielded dark blue crystals of the insertion product [Ga(P 4 )(PDI dipp )] + [Al(OR F ) 4 ] − 11 (Figure 5a/b). This reactivity contrasts the previously reported formation of a triphosphenium cation in the reaction of [{In(dmpe)} 4 ] 4+ ([Al(OR F ) 4 ] − ) 4 with white phosphorous [15] …”

“…This was previously shown in the synthesis of polycationic [Ga x ] x+ clusters by addition of dimethylaminopyridine (x=5), [14] tert ‐butyl isocyanide (x=4), or dimethylphosphinoethylene (x=4) to I (Scheme 1) [15] as well as the intermetallic [Ga 2 (AlCp*) 6 ] 2+ dication [16] . The surprisingly high stability of the formed Ga−Ga bonds impeded the activation of small molecules such as white phosphorous in a previous study [15] . Umpolung of the reactivity of a Sn II cation by a tris(carbene)borate ligand has also been previously reported by Liu [17] …”

“…However, the lone‐pair orbital at the Gallium cation can be activated by addition of strong σ‐donors. This was previously shown in the synthesis of polycationic [Ga x ] x+ clusters by addition of dimethylaminopyridine (x=5), [14] tert ‐butyl isocyanide (x=4), or dimethylphosphinoethylene (x=4) to I (Scheme 1) [15] as well as the intermetallic [Ga 2 (AlCp*) 6 ] 2+ dication [16] . The surprisingly high stability of the formed Ga−Ga bonds impeded the activation of small molecules such as white phosphorous in a previous study [15] .…”

Coordination of Pnictogenylboranes Towards Tl(I) Salts and a Tl‐ Mediated P−P Coupling

“…The obtained complexes reveal a trigonal‐pyramidal coordination at the group 13 metal atom in the solid state for PPh 3 , while the increased steric bulk of P t Bu 3 leads to carbene‐analogous bis‐phosphine complexes. Very recently, Krossing and coworkers also reported on bis(dimethylphosphino)ethane‐stabilized indium and gallium tetracationic salts (Figure 1, IVa , IVb ) [12] …”

Strukturen, Bindungsanalyse und Reaktivität eines dikationischen Digallens und eines Diindens, die trans‐gefaltete Ditetrylene nachahmen

“…Darüber hinaus sind homo‐ und heterodiatomare Doppelbindungen zwischen schweren Elementen der Gruppe 15 [26] und 13 [23,27–29] bekannt. Erst kürzlich haben wir das erste dikationische, dikoordinierte Digallen [LGa I Ga I L] 2+ isoliert, wenn auch mit einer sehr schwachen Ga−Ga‐Bindung und L=Hexaphenylcarbodiphosphoran (CDP Ph ) [30] . In diesem Zusammenhang und verstärkt durch die kontroversen Diskussionen [13,31] über Robinson's “Digallin”, [32] stellen wir fest, dass die Zuordnung von formalen Mehrfachbindungsordnungen zwischen schwereren Hauptgruppenmetallen oft nicht eindeutig möglich ist.…”