Hexaaryltellurium, the First Neutral Compounds Comprising Hexaarylated Elements

Chalcogenuranyl dications bearing unusual bonds and charges

“…Hence we tried to prepare higher coordinated chalcogenuranes bearing carbon ligands. The aim of this study was to prepare hexacoordinated chalcogenuranes bearing only carbon ligands, similar to those reported by Akiba and Minoura [7]. We also succeeded in the isolation of hexacoordinated chalcogenuranes bearing only carbon ligands, but this is reported elsewhere [8].…”

Syntheses and Properties of Tetrakis(pentafluorophenyl)tellurium, Te(C6F5)4, and Related Compounds — Single Crystal Structures of Tris(pentafluorophenyl)tellurium Bromide, Te(C6F5)3Br, Tris(pentafluorophenyl)tellurium Trifluoromethanesulfonate, [Te(C6F5)3][OSO2CF3], and Bis(pentafluorophenyl)tellurium Oxide, Te(C6F5)2O

“…While the reaction with elemental bromine in the exact stoichiometry 1:1 selectively gave Te(C 6 F 5 ) 3 Br even a small excess of Br 2 caused the formation of Te(C 6 F 5 ) 2 Br 2 as a by-product. Excess of bromine Z. Anorg.…”

“…In contrast, if a not carefully dried nitrogen or argon stream was passed over saturated solutions of Te(C 6 F 5 ) 4 in benzene, toluene and toluene-d 8 4 , Te(C 6 F 5 ) 3 Cl and Te(C 6 F 5 ) 3 Br in the solid state heating samples to 250°C in molten 4 mm glass tubes gave exclusively 19 F NMR spectroscopic evidence for C 6 F 5 X (X ϭ C 6 F 5 , Cl, Br) and Te(C 6 F 5 ) 2 .…”

“…The following uncorrected values were determined: Te(C 6 F 5 ) 4 200 ± 2°C; Te(C 6 F 5 ) 3 Br · C 6 H 6 100 Ϫ 102°C (loss of benzene), Te(C 6 F 5 ) 3 The visible decomposition point of Te(C 6 F 5 ) 4 is in good agreement with the value of the reaction product of TeCl 4 and LiC 6 F 5 [9]. DTA / TG measurements of Te(C 6 F 5 ) 4 exhibit a melting point of 159°C and a decomposition point of 208°C.…”

“…Te(C 6 F 5 ) 3 Cl and Te(C 6 F 5 ) 3 Br were unexpectedly formed as reaction products with the solvents CHCl 3 or CHBr 3 during the attempted preparation of Te(C 6 F 5 ) 2 (CN) 2 via ligand exchange reactions of Te(C 6 F 5 ) 2 X 2 (X ϭ Cl, Br) with AgCN and Me 3 SiCN, respectively. Scheme 1 Possible pathways for the synthesis of Te(C 6 F 5 ) 4 Salt-like compounds with the [Te(C 6 F 5 ) 3 ] ϩ and [Te(C 6 F 5 ) 2 (2,4,6-F 3 C 6 H 2 )] ϩ cations had been synthesised via electrophilic arylations using [XeC 6 F 5 ] ϩ [15] and [Xe(2,4,6-F 3 C 6 H 2 )] ϩ [16] derivatives.…”