Hexakis(2,4,6-triisopropylphenylsilsesquioxane)

Hexasilsesquioxanes bearing bulky Tip (2,4,6-triisopropylphenyl) groups were synthesized and the structure was determined. The X-ray crystal analysis revealed that the enantiomer pair originating from the restricted rotation of the bulky Tip groups was included in the single lattice. In solution, evidence for the rapid interconversion of both enantiomers was encountered in ¹H NMR. Thus, variable temperature NMR indicated peak broadeningupon warming the sample, with a coalescence temperature of 38 ° C. Kinetic parameters of the rotation were also calculated.     

Facile Synthesis of Hexakis(4-Formylphenoxy)-Cyclotriphosphazene and Hexakis(4-Acetophenoxy)-Cyclotriphosphazene

Synthesis of hexakis(4-formylphenoxy)cyclotriphosphazene and similar compounds may be achieved utilizing a phase-transfer reaction. This one-pot procedure eliminates the need for rigorous drying of solvents, purification of reagents, and reflux conditions during the reaction.     

Chemistry and Structures of Hexakis(halogenomethyl)‐, Hexakis(azidomethyl)‐, and Hexakis(nitratomethyl)disiloxanes

An investigation of the structures and chemistry of substituted hexamethyl disiloxanes ((XCH₂)₃Si)₂O; X=F, Cl, Br, I, N₃, and ONO₂) is reported. New synthetic routes to the precursor hexakis(chloromethyl)disiloxane are presented. The products with X=Cl, Br, I, and N₃ were characterized by NMR, IR, and Raman spectroscopy. In addition, the single‐crystal structures of the products with X=Cl, Br, and I are discussed in detail. The compounds with X=F and ONO₂ were not obtained in their pure form; instead investigations of the decomposition products revealed their conversion into intermediates. Theoretical calculations of the gas‐phase structures at the B3LYP/cc‐pVDZ, B3LYP/3‐21G, MP2/6‐31G*, and MP2/3‐21G levels of theory are used to explain the chemical and physical behavior of the compounds with X=Cl, Br, I, N₃, and ONO₂. A new decomposition pathway of hexakis(nitratomethyl)disiloxane is presented and is used to explain their remarkable instability. The energetic properties and values of the nitrate and azide derivatives were calculated at the CBS‐4M level of theory by using the improved EXPLO5 computer code version 6.01.     

Hexakis(adamantyltrimethylammonium) cyclooctasilicate tetratetracontahydrate

The title compound, 6C₁₃H₂₄N⁺·H₂Si₈O₂₀⁶⁻·44H₂O, belongs to the class of cyclosilicate hydrates, which structurally can be positioned between the zeosils and the clathrate hydrates. [Si₈O₁₈(OH)₂] cubes carrying six negative charges are located on crystallographic inversion centres and are surrounded by six adamantyltrimethylammonium cations.     

Synthesis of Hexakis(vinylthio)benzene

Exhaustive nucleophilic replacement of fluorine atoms in hexafluorobenzene by vinylthio groups was accomplished by the action of sodium ethenethiolate in dimethylformamide-liquid ammonia at -5 to 0°C.     

Hexakis(melaminium) tetrakis(dihydrogenphosphate) monohydrogenphosphate tetrahydrate

The crystal structure of the new melaminium salt, hexa­kis(2,4,6‐tri­amino‐1,3,5‐triazin‐1‐ium) tetrakis­(di­hydrogenphos­phate) mono­hydrogenphosphate tetrahydrate, 6C₃H₇N₆⁺·4H₂PO₄^?·HPO₄^2?·4H₂O, is built up from singly protonated melaminium residues, di­hydrogenphosphate and mono­hydrogen­phosphate anions, and water mol­ecules. The melaminium residues are interconnected by four N—H?N hydrogen bonds, forming chains along the [001] direction. These chains of melaminium residues form stacks aligned along [100]. The di­hydrogenphosphate anions interact with the mono­hydrogenphosphate anions via the H atoms and, together with hydrogen‐bonded dimers of the water mol­ecules, develop layers parallel to the (010) plane. The oppositely charged moieties interact via multiple N—H?O hydrogen bonds that stabilize the stacking structure.