Gallium‐Indium Ordering in the Complex [Ni2Ga3In] Network of GdNi2Ga3In

Polycrystalline samples of the isotypic quaternary compounds RENi₂Ga₃In (RE = Y, Gd – Tm) were obtained by arc‐melting of the elements. Crystals of the gadolinium compound were found by slow cooling of an arc‐melted button of the initial composition “GdNiGa₃In”. All samples were characterized by powder X‐ray diffraction. The structure of GdNi₂Ga_2.89In_1.11 was refined from single‐crystal X‐ray diffractometer data: new type, Pnma, a = 2426.38(7), b = 418.17(2), c = 927.27(3) pm, wR₂ = 0.0430, 1610 F² values and 88 variables. Two of the six crystallographically independent gallium sites show a small degree of Ga/In mixing. The nickel atoms show tricapped trigonal prismatic coordination by gadolinium, gallium, and indium. Together, the nickel, gallium, and indium atoms build up a complex three‐dimensional [Ni₂Ga₃In]^δ– network, which leaves cages for the gadolinium atoms. The indium atoms form zigzag chains with In–In distances of 337 pm. The crystal chemical similarities of the polyhedral packing in the GdNi₂Ga₃In and La₄Pd₁₀In₂₁ structures are discussed.     

Reaktionen von R4Sb2 (R = Me,Et) mit (Me3SiCH2)3M (M = Ga,In) und Kristallstrukturen von [(Me3SiCH2)2InSbMe2]3 und [(Me3SiCH2)2GaOSbEt2]2

Reactions of R₄Sb₂ (R = Me, Et) with (Me₃SiCH₂)₃M (M = Ga, In) and Crystal Structures of [(Me₃SiCH₂)₂InSbMe₂]₃ and [(Me₃SiCH₂)₂GaOSbEt₂]₂ The reaction of (Me₃SiCH₂)₃In with Me₂SbSbMe₂ gives [(Me₃SiCH₂)₂InSbMe₂]₃ ( 1 ) and Me₃SiCH₂SbMe₂. [(Me₃SiCH₂)₂GaOSbEt₂]₂ ( 2 ) is formed by the reaction of (Me₃SiCH₂)₃Ga with Et₂SbSbEt₂ and oxygen. The syntheses and the crystal structures of 1 and 2 are reported.     

Insertion von Rhodizonsäure in die Gallium‐Gallium‐ bzw. Indium‐Indium‐Bindungen von Digallan(4)‐ bzw. Diindan(4)‐Verbindungen

Insertion of Rhodizonic Acid into the Gallium‐Gallium and Indium‐Indium Bonds of Digallane(4) and Diindane(4) Compounds Rhodizonic acid (C₆O₆H₂, 5, 6‐dihydroxy‐5‐cyclohexene‐1, 2, 3, 4‐tetraone) did not react with tetrakis[bis(trimethylsilyl)methyl] digallane(4) ( 1 ) and the corresponding diindium compound ( 2 ) by the transfer of protons. Instead the acid was completely inserted into the element‐element bonds of the starting compounds and the gallium or indium atoms were oxidized from the oxidation state of +II to +III. In contrast to the free acid, the OH groups of the products are not attached to neighbouring carbon atoms, but occupy the 1, 4‐positions of the central six‐membered rings. Both dialkylgallium and dialkylindium groups of the products ( 3 (Ga) and 4 (In)) are coordinated by two oxygen atoms. They adopt opposite positions at the C₆O₆ molecular core.     

Chirale Gallium‐ und Indium‐Alkoxometallate

Chiral Gallium and Indium Alkoxometalates Li₂(S)‐BINOLate ((S)‐BINOL = (S)‐(–)‐2,2′‐Dihydroxy‐1,1′‐binaphthyl) generated by dilithiation of (S)BINOL with two equivalents ⁿBuLi was reacted with GaCl₃ und InCl₃ in THF to the alkoxometalates [{Li(THF)₂}{Li(THF)}₂{Ga((S)‐BINOLate)₃}] ( 1 ) and [{Li(THF)₂}₂{Li(THF)}{In((S)‐BINOLate)₃}] · [{Li(THF)₂}{Li(THF)}₂{In((S)‐ BINOLate)₃}]₂ ( 3 ), respectively. 1 and 3 crystallize from THF/toluene mixtures as 1 · 2 toluene and 3 · 8 toluene. The treatment of PhCH₂GaCl₂ with Li₂(S)‐BINOLate in THF under reflux, followed by recrystallization of the product from DME gives the gallate [{Li(DME)}₃{Ga((S)BINOLate)₃}] · 1.5 THF ( 2 · 1.5 THF). 1 – 3 were characterized by NMR, IR and MS techniques. In addition, 1 · 2 toluene, 2 · 1.5 THF and 3 · 8 toluene were investigated by X‐ray structure analyses. According to them, a distorted octahedral coordination sphere around the group 13 metal was formed, built‐up by three BINOLate ligands. The three Li⁺ counter ions act as bridging units by metal‐oxygen coordination. The coordination sphere of the Li⁺ ions was completed, depending on the available space, by one or two THF ligands ( 1 · 2 toluene, 3 · 8 toluene) and one DME ligand ( 2 · 1.5 THF), respectively. The sterical dominance of the BINOLate ligands can be shown by the almost square‐planar coordination of the Li⁺ ions in 2 · 1.5 THF giving a small twisting angle of only 17°.     

Reaktion von (R,R)‐(N,N′)‐Diisopropylcyclohexyl‐1,2‐diamin mit Me2MCl (M = Ga,In)

Reaction of (R,R)‐(N,N′)‐Diisopropylcyclohexyl‐1,2‐diamine with Me₂MCl (M = Ga, In) (R,R)‐(N,N′)‐Diisopropylcyclohexyl‐1,2‐diamine (H₂L) was reacted with Me₂GaCl and Me₂InCl in boiling toluene, respectively. In both cases the salt [Me₂M(H₂L)][Me₂MCl₂] [M = Ga ( 1 ), In ( 2 )] was formed. 1 and 2 were characterized by NMR and vibrational spectroscopy. In addition, an X‐ray structure determination was applied on 2 . According to the spectroscopical and structural findings 1 and 2 consist of cations [Me₂M(H₂L)]⁺ and anions [Me₂MCl₂]^?.     

Neue viergliedrige GaE‐ und InE‐Ringverbindungen: Synthese und Kristallstruktur von [Et2InE(SiMe3)2]2 und [GaCl(PtBu2Me)E(SiMe3)]2 (E = P,As)

New GaE and InE Four Membered Ring Compounds: Syntheses and Crystal Structures of [Et₂InE(SiMe₃)₂]₂ and [GaCl(P t Bu₂Me)E(SiMe₃)]₂ (E = P, As) Et₃In · PR₃ (R = Et, iPr) reacts with H₂ESiMe₃ under liberation of C₂H₆ and EH₃ to form the cyclic compounds [Et₂InE(SiMe₃)₂]₂ ( 1 a : E = P, 1 b : E = As). 1 consists of a planar four membered In₂E₂ ring in which the indium and phosphorus or arsenic atoms are four coordinated. In contrast, the phosphorus/arsenic atoms in [GaCl(PtBu₂Me)E(SiMe₃)]₂ ( 2 a : E = P, 2 b : E = As) only have the coordination number three. 2 results from the reaction of GaCl₃ · PtBu₂Me with As(SiMe₃)₃ or Li₂PSiMe₃ respectively, and displays a folded four membered Ga₂E₂ ring as central structural motif. 1 and 2 have been characterised by single crystal X‐ray diffraction analysis as well as ¹H and ³¹P{¹H} NMR spectroscopy.     

Das Hexagallan [Ga6{SiMe(SiMe3)2}6] und das closo‐Hexagallanat [Ga6{Si(CMe3)3}4(CH2C6H5)2]2— — der Übergang zu einem ungewöhnlichen precloso‐Cluster

The Hexagallane [Ga₆{SiMe(SiMe₃)₂}₆] and the closo‐Hexagallanate [Ga₆{Si(CMe₃)₃}₄ (CH₂C₆H₅)₂]^2— — the Transition to an Unusual precloso‐Cluster The closo hexagallanate [Ga₆R₄(CH₂Ph)₂]^2— (R = Si^tBu₃) as well as the hexagallane Ga₆R₆ (R = SiMe(SiMe₃)₂) with only six cluster electron pairs were isolated from reactions of “GaI” with the corresponding silanides. The structure of the latter is derived from an octahedron by a Jahn‐Teller‐distortion and is different from the capped trigonal bipyramidal one expected by the Wade‐Mingos rules. Both compounds were characterized by X‐ray crystallography. The bonding is discussed with simplified Ga₆H₆ and Ga₆H₆^2— models via DFT methods.     

Umsetzungen der Dielementverbindungen R2E–ER2 [E = Ga,In; R = CH(SiMe3)2] mit Lithium‐phenylethinid – Bildung von Addukten unter Erhalt der E–E‐Bindungen

Reactions of the Dielement Compounds R₂E–ER₂ [E = Ga, In; R = CH(SiMe₃)₂] with Lithium Phenylethynide – Formation of Adducts by Retention of the E–E Bonds Lithium phenylethynide reacted with the dielement compounds tetrakis[bis(trimethylsilyl)methyl]digallane(4) ( 2 ) and diindane(4) ( 3 ) as a Lewis‐base and gave by the addition of one ethynido ligand to one of the Lewis‐acidic central atoms the anionic adducts 4 and 5 with intact Ga–Ga and In–In single bonds. Thus, compounds were formed, in which tricoordinated, coordinatively unsaturated Ga or In atoms are neighbored to tetracoordinated, coordinatively saturated ones. The E–E bonds [255.83 pm in 4 (Ga–Ga) and 285.24 pm in 5 (In–In)] are only slightly lengthened compared to those of the starting compounds 2 and 3 . A dynamic behavior with a fast change of the position of the ethynido ligand was observed for both compounds in solution at room temperature.     

[Ga6R8]2– (R = SiPh2Me): Eine metalloide Clusterverbindung mit einem unerwarteten Ga6‐Gerüst

[Ga₆R₈]^2– (R = SiPh₂Me): A Metalloid Cluster Compound with an Unexpected Ga₆‐Frame The reaction of a metastable solution of GaBr with a solution of LiSiPh₂Me in a toluene/THF mixture results in orange coloured crystals of [Ga₆(SiPh₂Me)₈]^2– · 2 [Li(THF)₄]⁺ ( 1 ). The unexpected structure of the planar Ga₆ frame (C_2h) could also be realized with the help of DFT calculation. DFT calculations furthermore show that 1 is energetically favoured against an octahedral Ga₆R₆^2– species and R₂. In contrast calculations for the similar Al and B species show that in these cases the octahedral entities are favoured. These results demonstrate that even for similar compounds of B, Al, and Ga Wade rules are too general and that they cannot predict the correct structure. Moreover the atomic arrangement within 1 shows that a structure is preferred which is also present in allotropic β‐Ga and that therefore clusters of this type should be called metalloid or more general elementoid.     

Synthese,NMR‐Spektren und Molekülstruktur von [(CH3)2Ga{μ‐P(H)Si(CH3)3}2Ga(CH3)2{μ‐P(Si(CH3)3)2}Ga(CH3)2]

Synthesis, NMR Spectra and Structure of [(CH₃)₂Ga{μ‐P(H)Si(CH₃)₃}₂Ga(CH₃)₂{μ‐P(Si(CH₃)₃)₂}Ga(CH₃)₂] The title compound has been prepared in good yield by the reaction of [Me₂GaOMe]₃ (Me = CH₃) with HP(SiMe₃)₂ in toluene (ratio 1 : 1,1) and purified by crystallization from pentane or toluene, respectively. This organogallium compound forms (Ga–P)₃ ring skeletons with one Ga–P(SiMe₃)₂–Ga and two Ga–P(H)SiMe₃–Ga bridges and crystallizes in the monoclinic space group C2/c. The known homologous Al‐compound is isotypic, both (M^III–P)₃ heterocycles have twist‐conformations, the ligands of the monophosphane bridges have trans arrangements.     

Studien zur Reaktion von [Me2AlP(SiMe3)2]2 mit basenstabilisierten Organogalliumchloriden und ‐hydriden

Investigations on the Reactivity of [Me₂AlP(SiMe₃)₂]₂ with Base‐stabilized Organogalliumhalides and ‐hydrides [Me₂AlP(SiMe₃)₂]₂ ( 1 ) reacts with dmap?Ga(Cl)Me₂, dmap?Ga(Me)Cl₂, dmap?GaCl₃ and dmap?Ga(H)Me₂ with Al‐P bond cleavage and subsequent formation of heterocyclic [Me₂GaP(SiMe₃)₂]₂ ( 2 ) as well as dmap?AlMe_xCl_3?x (x = 3 8 ; 2 3 ; 1 4 ; 0 5 ). The reaction between equimolar amounts of dmap?Al(Me₂)P(SiMe₃)₂ and dmap?Ga(t‐Bu₂)Cl yield dmap?Ga(t‐Bu₂)P(SiMe₃)₂ ( 6 ) and dmap?AlMe₂Cl ( 3 ). 2 – 8 were characterized by NMR spectroscopy, 2 and 6 also by single crystal X‐ray diffraction.