Reactions of bromine fluoride dioxide, BrO2F, for the generation of the mixed‐valent bromine oxygen cations Br3O4+ and Br3O6+

A reliable synthesis of unstable and highly reactive BrO2F is reported. This compound can be converted into BrO2+SbF6−, BrO2+AsF6−, and BrO2+AsF6−⋅2 BrO2F. The latter decomposes into mixed‐valent Br3O4⋅Br2+AsF6− with five‐, three‐, one‐, and zero‐valent bromine. BrO2+ H(SO3CF3)2− is formed with HSO3CF3. Excess BrO2F yields mixed‐valent Br3O6+OSO3CF3− with five‐ and three‐valent bromine. Reactions of BrO2F and MoF5 in SO2ClF or CH2ClF result in Cl2BrO6+Mo3O3F13−. The reaction of BrO2F with (CF3CO)2O and NO2 produces O2Br‐O‐CO‐CF3 and the known NO2+Br(ONO2)2−. All of these compounds are thermodynamically unstable

Attempts to Synthesize a Thiirane, Selenirane, and Thiirene by Dealkylation of Chalcogeniranium and Thiirenium Salts

Thiiranium salts [Ad(2)SR]X-+(-)(5,8,9,11,12; X-=Tf2N-(Tf=CF3SO2), SbCl6-) and seleniranium salts [Ad(2)SeR]X-+(-)(14,16,17,23-25; X-=Tf2N-, BF4-, CHB11Cl11-, SbCl6-) are synthesized from strained alkene bis(adamantylidene) (1). The disulfides and the diselenides (Me3SiCH2CH2E)(2)(4,13), (tBuMe(2)SiCH(2)CH(2)E)(2)(7,22), and (NCCH2CH2E)(2)(10,15; E=S, Se) have been used. The thiirenium salts [tBu(2)C(2)SR]X-+(-)(34) and [Ad(2)C(2)SR]X-+(-)(35,36) are prepared from the bis-tert-butylacetylene (2) and bis-adamantyl-acetylene (3) with R=Me(3)SiCH(2)CH(2)andtBuMe(2)SiCH(2)CH(2). Attempts to cleave off the groups Me3SiCH2CH2,tBuMe(2)SiCH(2)CH(2), and NCCH(2)CH(2)resulted in thiiranes27,30. No selenirane Ad(2)Se (33) is formed from seleniranium salts, instead cleavage to the alkene (1) and diselenide (13,15) occurs. The thiirenium salt [Ad(2)C(2)SCH(2)CH(2)SiMe(3)]+Tf2N-(35) does not yield the thiirene Ad(2)C(2)S (37), the three-membered ring is cleaved, forming the alkyne (3) and disulfide (4). All compounds are characterized by ESI mass spectra, NMR spectra, and by quantum chemical calculations. Crystal structures of the salts8,12,25,17,26,36and the thiiranes27,30are presented

Spectroscopic Evidence for Pseudorotation of Seven-Membered Chalcogen Rings in Solution [1]

The 77Se NMR spectrum of l,2-Se2S5 exhibits one singlet at 1077.3 ppm indicating pseudorotation in solution; the same conclusion is reached from the solution Raman spectrum of S7 showing characteristic line broadening compared to the solid state spectrum

From Missing Links to New Records: A Series of Novel Polychlorine Anions

Herein we report the synthesis and structural characterization of four novel polychloride compounds. The compounds [CCl(NMe2)2][Cl(Cl2)3] and [NPr4][Cl(Cl2)4] have been obtained from the reaction of the corresponding chloride salts with elemental chlorine at low temperature. They are the missing links in the series of polychloride monoanions [Cl(Cl)n]− (n=1–6). Additionally, the reaction of decamethylferrocene with elemental chlorine was studied yielding [Cp*2Fe]2[Cl20], which contains the largest known polychloride [Cl20]2− to date, and [Cp*2Fe][Cl(Cl2)4(HF)], which is the first example of a polychloride‐HF network stabilized by strong hydrogen and halogen bonding. All compounds have been characterized by single‐crystal X‐ray diffraction, Raman spectroscopy and quantum‐chemical calculations

Crystal structure of bis(fluorosulfato-κO)xenon(II), Xe(SO3F)2

Thermally unstable Xe(SO3F)2 has been prepared by the reaction of XeF2 with HSO3F. Single crystals were obtained from HSO3F by slow cooling in a sealed tube. The molecular structure is characterized by the Xe atom covalently bonded to two O atoms of two fluorosulfate tetrahedra in an almost linear fashion [O—Xe—O = 179.13 (4)°]. The crystal packing is strongly influenced by intermolecular van der Waals forces

Synthesis and X-ray crystal structure of pyrrolo [1, 2-a] benzimidazoles

Reaction of nitrilimines 1 with 2-cyanomethylbenzimidazole 2 gave the 3-arylazo-2-methylpyrrolo[1,2-a]benzimidazole 4a rather than the reported 2-arylazo-3-methylpyrrolo[1,2-a]benzimidazole 3a. The correct structure of the product was determined using X-ray crystal structure analysis. The similar reaction of nitrilimines with 2-aminobenzimidazole 5 gave the acyclic nucleophilic addition product 6