Reaction of AlX3 (X = Cl, Br) with R*Na (R* = supersilyl, Si(t-Bu)3) in heptane at room temperature gave the ruby dialane R*2Al−AlR*2 (1). X-ray structure analysis showed it to contain a Si2Al−AlSi2 skeleton with D 2 d symmetry and the longest Al−Al bond to date (2.751(2) Å). Water- and air-sensitive 1 reacts with iodine or hydrogen to form R*2AlI or R*2AlH, respectively. Thermolysis and photolysis transform 1, via [R*2Al−AlR*]•, into the tetraalatetrahedrane Al4R*4.

The reduction of black‐blue tris(supersilyl)digallanyl [R*2Ga−GaR*]· (R* = SitBu3 = supersilyl) in organic solvents with Na, NaC10H8, or NaR* leads to deep‐red sodium tris(supersilyl)digallanide−THF(1/3) NaGa2R*3×3THF = [R*2Ga−GaR*Na(THF)3], which transforms in the presence of 18‐crown‐6 into deep‐blue sodium tetrakis(supersilyl)trigallanide−18‐crown‐6(1/1)−THF(1/2) [Na(18‐C‐6)(THF)2]+[R*2Ga−GaR*−GaR*]−.The oxidation of the latter anion with R*Br or TCNE as well as the reaction of the digallanyl R*3Ga2· with R*Br leads to deep‐green tetra(supersilyl)cyclotrigallanyl [···R*Ga−GaR*2−GaR*···]·. The latter radical thermolizes at 100 °C to dark‐violet tetrakis(supersilyl)‐tetrahedro‐tetragallane R*4Ga4 besides the digallanyl R*3Ga2·. This is also prepared from NaR* and GaCl3 or R*2GaCl, as well as by oxidation of R*3Ga2−, and itself thermolizes with formation of the tetrahedrane R*4Ga4. According to X‐ray structure analyses of the mentioned compounds, the Ga−Ga bond of the digallanide NaGa2R*3×3THF (NMR spectroscopically observed) is comparably short (2.380 Å), approaching a bond order of 2. In fact, it is distinctly shorter than the Ga−Ga bond (2.420 Å) in the digallanyl R*3Ga2· (EPR spectroscopically observed). The Ga atoms of the trigallanyl R*4Ga3· (EPR spectroscopically observed) are located at the corners of a triangle with two shorter R*2Ga−GaR* sides (2.527 Å) and a comparably longer R*Ga−GaR* basis (2.879 Å). The mean value of the two Ga−Ga bonds in the trigallanide R*4Ga3− (NMR spectroscopically observed) is as long (2.53 Å) as the short Ga−Ga bonds in R*4Ga3·. The anion shows an intramolecular CH3···Ga contact (C−Ga 2.10 Å) between one peripheral methyl group of the R*2Ga entity and the anionic Ga atom in [R*2Ga−GaR*−GaR*]−.

2,4‐Bis(triphenylphosphanimino)tetrazolo[5,1‐a][1,3,5]triazine (1) was synthesized by reaction of cyanuric azide with triphenylphosphane. 1 is characterized by X‐ray structural analysis, IR, Raman, and NMR spectroscopy. The obtained spectra showed that the remaining azide group in 1 reacts with the N4 atom of the triazine ring and forms a tetrazole. An improved crystal structure for 2,4,6‐triazido‐1,3,5‐triazine (2) was determined and for the first time a 14N‐NMR spectrum was obtained. CAUTION: 2 (Cyanuric azide) is explosive! The explosive nature increases with greater purity and crystal size.

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Disupersilylmetalle (tBu3Si)2Zn (farblos), (tBu3Si)2Cd (blaßgelb), (tBu3Si)2Hg (blaßgelb) und Supersilylmetallhalogenide tBu3SiZnCl(THF) (farblos), tBu3SiCdI (farblos), tBu3SiHgCl (farblos) bilden sich in THF durch Einwirkung von tBu3SiNa auf ZnCl2, CdI2, HgCl2 im Molverhältnis 2 : 1 bzw. 1 : 1. THF läßt sich durch TMEDA unter Bildung von tBu3SiZnCl(TMEDA) (farblos) ersetzen, (tBu3Si)2Zn durch Einwirkung von BiCl3 oder BBr3 in tBu3SiZnCl (farblos) oder tBu3SiZnBr (farblos) umwandeln. Gemäß Röntgenstrukturanalysen sind die Verbindungen (tBu3Si)2M monomer mit linearen SiMSi‐Gerüsten, wogegen tBu3SiZnBr und tBu3SiHgCl tetramer sind, und zwar in ersterem Falle mit regulärem, in letzterem mit ausgeprägt irregulärem kubischem M4X4‐Gerüst. Die Verbindungen sind bis 200°C thermostabil (Ausnahme (tBu3Si)2Cd), photolabil und vergleichsweise stabil gegen Wasser und Sauerstoff. Die Disupersilylmetalle wirken als Quellen für Supersilylradikale tBu3Si (bei Bestrahlung) sowie als milde Supersilanidierungsmittel (z. B. (tBu3Si)2Zn/BBr3 → tBu3SiZnBr/tBu3SiBBr2), die Supersilylmetallhalogenide als Lewis‐Säuren (Bildung von tBu3SiMX · Donor) und Elektrophile (z. B. tBu3SiHgCl/RLi → tBu3SiHgR/LiCl).

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The reaction of zirconocene dichloride with 2 equiv of butyllithium and 1-trimethylsilylpropyne yields yellow 1,1-bis(cyclopentadienyl)-3,4-dimethyl-2,5-bis(trimethylsilyl)zirconacyclopenta-2,4-diene, 1. The metathesis reaction of 1 with PCl3 gives a mixture of 1-chloro- and 1-cyclopentadienyl-3,4-dimethyl-2,5-bis(trimethylsilyl)-1-phosphacyclopenta-2,4-diene, which was allowed to react in THF with distilled calcium. Crystallization of the product from THF solution gave dimeric bis(tetrahydrofuran-O)dicalcium bis[3,4-dimethyl-2,5-bis(trimethylsilyl)-1-phosphacyclopenta-2,4-dienide] cyclopentadienide chloride, 2. The metathesis reaction of 1 with AsCl3 yielded nearly quantitatively 1-chloro-3,4-dimethyl-2,5-bis(trimethylsilyl)-1-arsacyclopenta-2,4-diene, 3. 3,4-Dimethyl-2,5-bis(trimethylsilyl)-1-arsacyclopentadienyl bis(tetrahydrofuran-O)calcium chloride, 4, was isolated from the reduction of 3 with distilled calcium.