Bisvinylated [R–Ge₉–Ge₉–R]^4– Cluster Dimers

Abstract

The syntheses, crystal structures, and NMR and Raman spectroscopic characterization of two compounds with a new member of the organically functionalized dimeric Ge9–Ge9 polyanion [R–Ge9–Ge9–R]4– with R = CH=CH2 are presented. [K([2.2.2]crypt)]4[(CH2=CH)–Ge9–Ge9–(CH=CH2)]·1.76 en (1) was synthesized either at elevated temperature by the reaction of K4Ge9 and bis(trimethylsilyl)acetylene in ethylenediamine or at ambient temperature in the presence of Pt(PPh3)4. [K(18crown‐6)]4[(CH2=CH)–Ge9–Ge9–(CH=CH2)]·4 en (2) was obtained from the prefabricated monomeric bisvinylated Ge9 cluster [Ge9(CH=CH2)2]2– and an ethylenediamine solution of the intermetallic compound K4.79Co0.79Sn9. The reductive cleavage of one or two vinyl groups from [Ge9(CH=CH2)2]2– – a prerequisite for the latter reaction – could be shown by reacting a solution of the divinylated [Ge9(CH=CH2)2]2– anion in liquid ammonia with elemental potassium, which resulted in the formation of the ligand‐free Ge94– cluster in the new compound [K5(OH)]Ge9(NH3)11 (3).

Silicon Containing Nine Atom Clusters from Liquid Ammonia Solution: Crystal Structures of the First Protonated Clusters [HSi9]3– and [H2{Si/Ge}9]2–

“…Similar results have been obtained with [Ge 9 ] 4– and [Sn 9 ] 4– containing compounds . The preparation of this compound was not intended and the source of the hydroxide was not finally identified, most probably it was introduced accidentally by a contaminated batch of moist ammonia, which was the only common ingredient in the related experiments including Ge or Sn clusters , . Because the otherwise easily emerging hydroxide‐free ammoniate 1 did not appear in this experiment we assume a favoring effect of hydroxide for crystal growth.…”

“…The tetrel Zintl compounds are sensitive against decomposition in presence of water, however, [Si 9 ] 4– units can exist with small amounts at the basic conditions in ammoniac solution as proven by the finding of the hydroxide‐containing compound 4 . Similar results have been obtained with [Ge 9 ] 4– and [Sn 9 ] 4– containing compounds . The preparation of this compound was not intended and the source of the hydroxide was not finally identified, most probably it was introduced accidentally by a contaminated batch of moist ammonia, which was the only common ingredient in the related experiments including Ge or Sn clusters , .…”

“…From a solution of K 12 Si 17 and ZnPh 2 in liquid ammonia crystals of the mixed silicide hydroxide K 5 Si 9 (OH) · 8NH 3 ( 4 ) were grown. Compounds of a similar composition have been obtained recently from different reactions including [Ge 9 ] 4– and [Sn 9 ] 4– Zintl clusters . 4 crystallizes in the orthorhombic space group Pna 2 1 , the structure consist of [Si 9 ] 4– clusters, [OH] – ions, K + cations, and NH 3 molecules.…”

On the Nature of Bridging Metal Atoms in Intermetalloid Clusters: Synthesis and Structure of the Metal‐Atom‐Bridged Zintl Clusters [Sn(Ge9)2]4− and [Zn(Ge9)2)]6−

“…The obtained deep brown filtrate was layered with as olution of 18-crown-6 (328 mg, 1.24 mmol) in toluene (8 mL). After 12 weeks deep red, block-shaped single crystals were isolated from the reaction mixture and used for single-crystal struc- [32] . EDX (%) found (calcd): K1 4.7 (24.0), Zn 3.9 (4.0), Ge 81.4 (72.0 %).…”

Reaction of SiCl2·dipp with K[Ge9{Si(SiMe3)3}3] – Synthesis and Characterization of [K(dipp)2][Ge9{Si(SiMe3)3}3]·tol and [dipp‐H][Ge9{Si(SiMe3)3}3]·2acn [dipp = 1,3‐Bis(2,6‐Diisopropylphenyl)imidazol‐2‐ylidene]

“…In addition to a considerable number of Ge 9 clusters with one or two exo ‐bonded main‐group fragments,, the phenyl‐ and alkyl‐substituted clusters [Ph–Ge 9 –SbPh 2 ] 2– and [ t Bu–Ge 9 –Ge 9 – t Bu] 4– were obtained . Besides, the vinylation of [ E 9 ] Zintl clusters using alkynes is probably one of the best studied derivation reaction of these clusters . Recently, the structure of the first deltahedral Zintl cluster anion [ R –Ge 9 –CH=CH–CH=CH–Ge 9 – R ] 4– [ R = (2 Z ,4 E )‐7‐amino‐5‐aza‐hepta‐2,4‐dien‐2‐yl], that are covalently linked by a conjugated C 4 unit was reported …”