Chalcogenido‐Dimethylgallates and ‐Indates DMPyr₂[Me₂M(μ₂−E)]₂ (M=Ga, In; E=S, Se): Building Blocks for Higher and Lower Order Chalcogenidoindates

Abstract

Metalation of the anions in the ionic liquids DMPyr[SH] and DMPyr[SeH] (DMPyr=1,1‐dimethylpyrrolidinium) by trimethylgallium and trimethylindium is investigated. The reaction proceeds via pre‐coordination of [EH]−, methane elimination and formation of an unprecedented series of chalcogenido metalates DMPyr2[Me2M(μ2−E)]2 (M=Ga, In; E=S, Se). These show the presences of dinuclear dianions with four‐membered ring structures displaying highly nucleophilic bridging chalcogenide ligands in their crystallographically determined molecular structures. Some representative reactions of these building blocks with amphoteric electrophiles were studied: Addition of two equivalents of E(SiMe3)2 (E=S, Se) to the indates DMPyr2[Me2In(μ2−S)]2 and DMPyr2[Me2In(μ2−Se)]2 leads to a cleavage of the ring, E silylation and formation of mononuclear, monoanionic indates DMPyr[Me2In(SSiMe3)2], DMPyr[Me2In(SeSiMe3)2], and even a mixed sulfido‐selenido dimethylindate DMPyr[Me2In(SSiMe3)(SeSiMe3)]. Reaction of DMPyr2[Me2In(μ2−S)]2 with two equivalents of Lewis acid Me3In leads to charge delocalization, ring expansion and formation of six‐membered ring DMPyr3[Me2In(μ2−S−InMe3)]3. The latter is a key intermediate in the formation of dianionic sulfidoindate DMPyr2[(Me2In)6(μ3−S)4] displaying an unusual inverse heteroadamantane cage structure with four capping sulfido ligands.

Adamantane-type clusters: compounds with a ubiquitous architecture but a wide variety of compositions and unexpected materials properties

“…The only other example of a group 16-based adamantane in this category is DMPyr2[S4(Me2In)6] (25, Figure 2), which is a decomposition side product of the six membered ring DMPyr3[Me2In(SInMe3)]3, which could not yet be synthesized in a pure form. [28] The single example featuring a transition metal [Ga(C6H5Me)2]2[{AgGa(OTf)3}4Ga6(OTf)4] (26, OTf = O3SCF3, Figure 2) comprises bridging triflate ligands between the gallium atoms, with the terminal gallium moieties connecting to three, and the atoms in the E position to four, ligands. [29] It is formed by silver triflate reacting with elemental gallium after ultrasonic activation.…”

“…Se, Na[BH4] / diglyme, 0 °C to 110 °C, 8h 2. THF•BH3 / diglyme B [27] Cs2[S4(BH2)6] (23) Na2[S4(BH2)6] (21), CsBr /H2O O [27] Cs2[Se4(BH2)6] (24) Na2[Se4(BH2)6] ( 22), CsBr /H2O O [27] DMPyr2[S4(InMe2)6] (25) DMPyr3[Me2In(SInMe3)]3 / THF, pentane, 14 days J [28] [Ga(C6H5Me)2]2[{AgGa(OTf)3}4Ga6(OTf)4] (26) AgOTf, Ga / Toluene, 45 °C, 1.5 h (ultrasonic activation) L [29] n Bu = normal butyl, t Bu = tertiary butyl, Diglyme = bis(2-methoxyethyl) ether, DMPyr = 1,1-dimethylpyrrolidinium, OTf = O3SCF3…”

“…2), which is a decomposition side product of the six membered ring DMPyr 3 [Me 2 -In(SInMe 3 )] 3 , which could not yet be synthesized in a pure form. 28 The single example featuring a transition metal [Ga(C 6 H 5 -Me) 2 ] 2 [{AgGa(OTf) 3 } 4 Ga 6 (OTf) 4 ] (26, OTf = O 3 SCF 3 , Fig. 2) comprises bridging triate ligands between the gallium atoms, with the terminal gallium moieties connecting to three, and the atoms in the E position to four, ligands.…”

“…2 ), which is a decomposition side product of the six membered ring DMPyr 3 [Me 2 In(SInMe 3 )] 3 , which could not yet be synthesized in a pure form. 28 …”