2 research outputs found
Derivatization of Phosphine Ligands with Bulky Deltahedral <i>Zintl</i> Clustersî—¸Synthesis of Charge Neutral Zwitterionic Tetrel Cluster Compounds [(Ge<sub>9</sub>{Si(TMS)<sub>3</sub>}<sub>2</sub>)<sup><i>t</i></sup>Bu<sub>2</sub>P]M(NHC<sup>Dipp</sup>) (M: Cu, Ag, Au)
Reactions of silylated clusters [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>]<sup>−</sup> or [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>]<sup>2−</sup> with
dialkylhalophosphines
R<sub>2</sub>PCl (Cy, <sup><i>i</i></sup>Pr, <sup><i>t</i></sup>Bu) at ambient temperature yield the first tetrel <i>Zintl</i> cluster compounds bearing phosphine moieties. Varying
reactivity of the dialkylhalophosphines toward the silylated clusters
is observed depending on the bulkiness of the phosphine’s alkyl
substituents and on the number of hypersilyl groups at the tetrel
cluster. Reactions between phosphines with small cyclohexyl- (Cy)
or isopropyl- (<sup><i>i</i></sup>Pr) groups and the tris-silylated
cluster [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>]<sup>−</sup> yield the novel neutral cluster compounds [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>PR<sub>2</sub>] (R: Cy (<b>1</b>), <sup><i>i</i></sup>Pr (<b>2</b>)) with discrete Ge–P <i>exo</i> bonds. By contrast, the bulkier phosphine <sup><i>t</i></sup>Bu<sub>2</sub>PCl does not react with [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>]<sup>−</sup> due to steric
crowding. However, the reaction with the bis-silylated cluster [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>]<sup>2</sup><sup>−</sup> yields the novel cluster compound [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>P<sup><i>t</i></sup>Bu<sub>2</sub>]<sup>−</sup> (<b>3</b>). Subsequent reactions of compound <b>3</b> with NHC<sup>Dipp</sup>MCl (M: Cu, Ag, Au) yield the charge neutral zwitterionic compounds
[(Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>)<sup><i>t</i></sup>Bu<sub>2</sub>P]ÂMÂ(NHC<sup>Dipp</sup>) (M:
Cu, Ag, Au) (<b>4</b>–<b>6</b>), in which compound <b>3</b> acts as a phosphine ligand bearing a bulky tetrel <i>Zintl</i> cluster moiety. Compounds <b>4</b>–<b>6</b> also represent the first uncharged examples for 3-fold substituted
tetrel <i>Zintl</i> clusters
Derivatization of Phosphine Ligands with Bulky Deltahedral <i>Zintl</i> Clustersî—¸Synthesis of Charge Neutral Zwitterionic Tetrel Cluster Compounds [(Ge<sub>9</sub>{Si(TMS)<sub>3</sub>}<sub>2</sub>)<sup><i>t</i></sup>Bu<sub>2</sub>P]M(NHC<sup>Dipp</sup>) (M: Cu, Ag, Au)
Reactions of silylated clusters [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>]<sup>−</sup> or [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>]<sup>2−</sup> with
dialkylhalophosphines
R<sub>2</sub>PCl (Cy, <sup><i>i</i></sup>Pr, <sup><i>t</i></sup>Bu) at ambient temperature yield the first tetrel <i>Zintl</i> cluster compounds bearing phosphine moieties. Varying
reactivity of the dialkylhalophosphines toward the silylated clusters
is observed depending on the bulkiness of the phosphine’s alkyl
substituents and on the number of hypersilyl groups at the tetrel
cluster. Reactions between phosphines with small cyclohexyl- (Cy)
or isopropyl- (<sup><i>i</i></sup>Pr) groups and the tris-silylated
cluster [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>]<sup>−</sup> yield the novel neutral cluster compounds [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>PR<sub>2</sub>] (R: Cy (<b>1</b>), <sup><i>i</i></sup>Pr (<b>2</b>)) with discrete Ge–P <i>exo</i> bonds. By contrast, the bulkier phosphine <sup><i>t</i></sup>Bu<sub>2</sub>PCl does not react with [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>3</sub>]<sup>−</sup> due to steric
crowding. However, the reaction with the bis-silylated cluster [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>]<sup>2</sup><sup>−</sup> yields the novel cluster compound [Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>P<sup><i>t</i></sup>Bu<sub>2</sub>]<sup>−</sup> (<b>3</b>). Subsequent reactions of compound <b>3</b> with NHC<sup>Dipp</sup>MCl (M: Cu, Ag, Au) yield the charge neutral zwitterionic compounds
[(Ge<sub>9</sub>{SiÂ(TMS)<sub>3</sub>}<sub>2</sub>)<sup><i>t</i></sup>Bu<sub>2</sub>P]ÂMÂ(NHC<sup>Dipp</sup>) (M:
Cu, Ag, Au) (<b>4</b>–<b>6</b>), in which compound <b>3</b> acts as a phosphine ligand bearing a bulky tetrel <i>Zintl</i> cluster moiety. Compounds <b>4</b>–<b>6</b> also represent the first uncharged examples for 3-fold substituted
tetrel <i>Zintl</i> clusters