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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