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1.
Chemistry ; 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737908

RESUMO

Thiiranium salts [Ad 2 SR] + X - ( 5 , 8 , 9 , 11 , 12 ) (X - = Tf 2 N - (Tf=CF 3 SO 2 ), SbCl 6 - ) and seleniranium salts [Ad 2 SeR] + X - ( 14 , 16 , 17 , 23 - 25 ) (X - = Tf 2 N - , BF 4 - , CHB 11 Cl 11 - , SbCl 6 - ) are synthetized from strained alkene bis(adamantylidene) ( 1 ). The disulfides and the diselenides (Me 3 SiCH 2 CH 2 E) 2 ( 4 , 13 ), ( t BuMe 2 SiCH 2 CH 2 E) 2 ( 7 , 22 ), and (NCCH 2 CH 2 E) 2 ( 10 , 15 ) (E = S, Se) have been used. The thiirenium salts [ t Bu 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 and t BuMe 2 SiCH 2 CH 2 . Attempts to cleave off the groups Me 3 SiCH 2 CH 2 , t BuMe 2 SiCH 2 CH 2 , and NCCH 2 CH 2 resulted in thiiranes 27 , 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 ] + Tf 2 N - ( 35 ) does not yield the thiiren 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 salts 8 , 12 , 25 , 17 , 26 , 36 and the thiiranes 27 , 30 are presented.

2.
Dalton Trans ; 48(45): 17078-17082, 2019 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-31701989

RESUMO

For the first time the crystal structure of a permethylated metallocene anion has been obtained. The 17 valence electron complex decamethylmanganocene Cp*2Mn is reduced by molten potassium in THF to its extremely air-sensitive anion [Cp*2Mn]-. The potassium salt [K(THF)2]+[Cp*2Mn]- crystallizes upon cooling from hot THF and forms infinite polymeric chains exhibiting strong KC contacts. In the presence of 18-crown-6 the polymeric structure is broken up. Crystals of [K(18-crown-6)(THF)2]+[Cp*2Mn]- were obtained upon slow cooling from THF to -80 °C displaying well separated cations and anions.

3.
Angew Chem Int Ed Engl ; 58(52): 18928-18930, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31622009

RESUMO

A reliable synthesis of unstable and highly reactive BrO2 F is reported. This compound can be converted into BrO2 + SbF6 - , BrO2 + AsF6 - , and BrO2 + AsF6 - ⋅2 BrO2 F. The latter decomposes into mixed-valent Br3 O4 ⋅Br2 + AsF6 - with five-, three-, one-, and zero-valent bromine. BrO2 + H(SO3 CF3 )2 - is formed with HSO3 CF3 . Excess BrO2 F yields mixed-valent Br3 O6 + OSO3 CF3 - with five- and three-valent bromine. Reactions of BrO2 F and MoF5 in SO2 ClF or CH2 ClF result in Cl2 BrO6 + Mo3 O3 F13 - . The reaction of BrO2 F with (CF3 CO)2 O and NO2 produces O2 Br-O-CO-CF3 and the known NO2 + Br(ONO2 )2 - . All of these compounds are thermodynamically unstable.

4.
Angew Chem Int Ed Engl ; 57(44): 14597-14601, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-30176109

RESUMO

The 16-valence electron species [Cp*2 Fe]2+ (Cp*=η-C5 Me5 ), formally featuring a tetravalent iron ion, quantitatively binds CO in HF solution to form the stable, diamagnetic carbonyl species [Cp*2 Fe(CO)]2+ . This dication forms salts in the presence of AsF6 - and SbF6 - that were crystallographically characterized. The molecular structure in crystals of [Cp*2 Fe(CO)](AsF6 )2 displays cyclopentadienyl rings that are clearly not parallel and an equatorially bound η1 -CO ligand. The formal oxidation state +IV of iron was investigated by 57 Fe Mössbauer spectroscopy and is supported by DFT computational analysis. A detailed spectroscopic characterization of the hitherto unprecedented high-valent iron carbonyl compounds is reported.

5.
Chemistry ; 24(64): 17155-17161, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30175485

RESUMO

Seleniranium salts [Ad2 SeR]+ X- (2-8), which are moderately stable at room temperature, were synthesized by addition of RSe+ X- equivalents to the bulky olefin bis(adamantylidene) Ad=Ad (1), where R is aryl or alkyl and X- is Tf2 N- , B(C6 F5 )4 - , or SbCl6 - . Unstable telluriranium salts [Ad2 TeR]+ X- (9-12) were obtained by addition of RTe+ X- equivalents to 1 (R=Ph, Et; X- =Tf2 N- , BF4 - ). The compounds were characterized by NMR spectroscopy and quantum chemical calculations, and the Se compounds also by ESI mass spectrometry. Crystal structures were determined for seleniranium salts 2 and 7 and telluriranium salt 9.

6.
Angew Chem Int Ed Engl ; 56(52): 16495-16497, 2017 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-29084371

RESUMO

During our studies towards the preparation of the pentagonal-pyramidal hexamethylbenzene dication C6 (CH3 )62+ , we isolated the unprecedented dicationic species C6 (CH3 )6 SO2+  (AsF6- )2 from the reaction of hexamethylbenzene with a mixture of anhydrous HF, AsF5 , and liquid SO2 . This compound can be understood as a complex of unknown SO2+ with hexamethylbenzene. Herein, we report on its synthesis, molecular structure, and spectroscopic characterization.

7.
Angew Chem Int Ed Engl ; 56(43): 13372-13376, 2017 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-28834022

RESUMO

Ferrocene, Cp2 Fe, is quantitatively protonated in a mixture of liquid HF/PF5 to yield [Cp2 FeH](PF6 ), which was characterized by 1 H/13 C NMR and 57 Fe Mössbauer spectroscopy as well as single-crystal X-ray diffraction analysis. X-ray diffraction analysis at 100 K revealed a disordered, iron-coordinated hydrido ligand, which was unambiguously located by aspherical atom refinement at 100 K, and by analyzing the non-disordered crystal structure at 30 K, revealing a non-agostic structure.

8.
Inorg Chem ; 55(23): 12254-12262, 2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27934406

RESUMO

The structures of three solvated monovalent cation salts of the superweak anion B12F122- (Y2-), K2(SO2)6Y, Ag2(SO2)6Y, and Ag2(H2O)4Y, are reported and discussed with respect to previously reported structures of Ag+ and K+ with other weakly coordinating anions. The structures of K2(SO2)6Y and Ag2(SO2)6Y are isomorphous and are based on expanded cubic close-packed arrays of Y2- anions with M(OSO)6+ complexes centered in the trigonal holes of one expanded close-packed layer of B12 centroids (⊙). The K+ and Ag+ ions have virtually identical bicapped trigonal prism MO6F2 coordination spheres, with M-O distances of 2.735(1)-3.032(2) Å for the potassium salt and 2.526(5)-2.790(5) Å for the silver salt. Each M(OSO)6+ complex is connected to three other cationic complexes through their six µ-SO2-κ1O,κ2O' ligands. The structure of Ag2(H2O)4Y is unique [different from that of K2(H2O)4Y]. Planes of close-packed arrays of anions are offset from neighboring planes along only one of the linear ⊙···âŠ™···âŠ™ directions of the close-packed arrays, with [Ag(µ-H2O)2Ag(µ-H2O)2)]∞ infinite chains between the planes of anions. There are two nearly identical AgO4F2 coordination spheres, with Ag-O distances of 2.371(5)-2.524(5) Å and Ag-F distances of 2.734(4)-2.751(4) Å. This is only the second structurally characterized compound with four H2O molecules coordinated to a Ag+ ion in the solid state. Comparisons with crystalline H2O and SO2 solvates of other Ag+ and K+ salts of weakly coordinating anions show that (i) N[(SO2)2(1,2-C6H4)]-, BF4-, SbF6-, and Al(OC(CF3)3)4- coordinate much more strongly to Ag+ than does Y2-, (ii) SnF62- coordinates somewhat more strongly to K+ than does Y2-, and (iii) B12Cl122- coordinates to K+ about the same as, if not slightly weaker than, Y2-.

9.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 1): 14-6, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26870575

RESUMO

In the complex cation of the binuclear solvated title salt, [Pt2F(SbF6)2(C8H12)2]SbF6·0.75HF, an F atom bridges the two platinum(II) atoms with a bond angle of 123.3 (2)°. The corresponding Pt-F bond lengths are in the range of other fluorine-bridged binuclear platinum(II) complexes. Two of the three SbF6 (-) anions each coordinate with one F atom to one platinum(II) atom. Including the η(4)-bound cyclo-octa-diene (COD) ligands, the overall coordination sphere of each platinum(II) atom is square-planar. The third SbF6 (-) anion is not bound to the complex. Hydrogen fluoride is present in the crystal structure as a solvent disordered over three positions, each with an occupancy of 0.25. F⋯F distances of 2.5512 (7), 2.6076 (8) and 3.2215 (10) Što surrounding SbF6 (-) anions are indicative of F-H⋯F hydrogen-bonding inter-actions although no H atoms could be localized for the disordered solvent mol-ecules. The resulting hydrogen-bonded network is three-dimensional.

10.
Inorg Chem ; 54(23): 11563-6, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26603819

RESUMO

The B12F12(-) radical anion was generated by oxidation of [CoCp2(+)]2B12F12(2-) with AsF5 in SO2. In the crystal structure of [CoCp2(+)]B12F12(-), the anion displays a lowered symmetry (D2h) instead of an Ih-symmetric dianion as a result of Jahn-Teller distortion. Moreover, shortening of the B-F bonds and subtle changes of the B-B bonds are observed. DFT calculations show that, for the unknown neutral B12F12, unprecedented structural isomers [e.g., octahedral B6(BF2)6] are energetically favored instead of an icosahedral structure. The structures and energetics are compared with those of the analogous chlorine compounds.

11.
Dalton Trans ; 44(45): 19659-62, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26351980

RESUMO

The crystal structure of O2F2 is obtained at -180 °C. In the solid state the molecule has the typical hydrogen peroxide structure that has been established long ago by electron diffraction and microwave spectroscopy. OF2 melts at -223.8 °C, so its structure is determined by powder X-ray data. The structure differs from the solid state structures of ozone and Br2O. O2F in its dissolved form as O2(+) HnFn+1(-) oxidizes palladium to the four valence state, as found some time ago. The first product formed at low temperatures is (O2(+)H3Pd2F12(-))n.

12.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 4): 363-5, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26029391

RESUMO

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 mol-ecular structure is characterized by the Xe atom covalently bonded to two O atoms of two fluoro-sulfate tetra-hedra in an almost linear fashion [O-Xe-O = 179.13 (4)°]. The crystal packing is strongly influenced by inter-molecular van der Waals forces.

13.
Chem Rev ; 115(2): 563-5, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25627818
14.
Chem Sci ; 6(1): 497-504, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28936305

RESUMO

One-electron oxidation of two series of diaryldichalcogenides (C6F5E)2 (13a-c) and (2,6-Mes2C6H3E)2 (16a-c) was studied (E = S, Se, Te). The reaction of 13a and 13b with AsF5 and SbF5 gave rise to the formation of thermally unstable radical cations [(C6F5S)2]˙+ (14a) and [(C6F5Se)2]˙+ (14b) that were isolated as [Sb2F11]- and [As2F11]- salts, respectively. The reaction of 13c with AsF5 afforded only the product of a Te-C bond cleavage, namely the previously known dication [Te4]2+ that was isolated as [AsF6]- salt. The reaction of (2,6-Mes2C6H3E)2 (16a-c) with [NO][SbF6] provided the corresponding radical cations [(2,6-Mes2C6H3E)2]˙+ (17a-c; E = S, Se, Te) in the form of thermally stable [SbF6]- salts in nearly quantitative yields. The electronic and structural properties of these radical cations were probed by X-ray diffraction analysis, EPR spectroscopy, and density functional theory calculations and other methods.

15.
Chem Rev ; 115(2): 1296-306, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25418862
16.
Acta Chim Slov ; 60(3): 491-4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24169702

RESUMO

Xenon and Iridiumhexafluoride react at temperatures above room temperature forming XeF+IrF6-. In presence of SbF5 FXe+IrSbF11- is formed. Xenon and Osmiumhexafluoride form in solution a blue charge transfer complex that cannot be isolated as a solid.


Assuntos
Ácido Fluorídrico/química , Irídio/química , Compostos de Ósmio/química , Xenônio/química , Modelos Químicos
17.
Angew Chem Int Ed Engl ; 52(49): 12838-42, 2013 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-24127390

RESUMO

No phlogiston but xenon is released when XeF2 /F(-) acceptors act as new one-electron oxidants. F(-) acceptors are Lewis acids BF3 , B(C6 F5 )3 , and Al{OC(CF3 )3 }3 , and silyl derivatives TfOSiMe3 , Tf2 NSiMe3 , Me3 Si(+) B(C6 F5 )4 (-) , and Me3 Si(+) CHB11 Cl11 (-) . The anions BF4 (-) , TfO(-) , Tf2 N(-) , FB(C6 F5 )3 (-) , FAl{OC(CF3 )3 }3 (-) , B(C6 F5 )4 (-) , or CHB11 Cl11 (-) can be introduced into oxidation products of R2 E2 (E=S, Se, Te), [FeCp2 ], [(FeCpS)4 ], tetrathiafulvalene, thianthrene, and (2,4-Br2 C6 H3 )3 N.

18.
Angew Chem Int Ed Engl ; 52(2): 767-9, 2013 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-23172658

RESUMO

Vanadium pentachloride and molybdenum and rhenium hexachloride are all thermally unstable but can be prepared by metathesis from the corresponding fluorides with BCl(3) at low temperatures. MoCl(6) is structurally related to ß-WCl(6), and ReCl(6) to α-WCl(6). VCl(5) is a dimer in the solid state (V red, Cl green).

19.
Chemistry ; 18(21): 6644-54, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22488870

RESUMO

The halogenated benzenes C(6)HF(5), 2,4,6-C(6)H(3)F(3), 2,3,5,6-C(6)H(2)F(4), C(6)F(6), C(6)Cl(6), C(6)Br(6), and C(6)I(6) were converted into their corresponding cation radicals by using various strong oxidants. The cation-radical salts were isolated and characterized by electron paramagnetic resonance (EPR) spectroscopy and by single-crystal X-ray diffraction. The thermal stability of the cation radicals increased with decreasing hydrogen content. As expected, the cation radicals [C(6)HF(5)](+) and 2,3,5,6-[C(6)H(2)F(4)](+) had structures with the same geometry as C(6)HF(5) and 2,3,5,6-[C(6)H(2)F(4)]. In contrast, the cation radicals [C(6)F(6)](+), [C(6)Cl(6)](+), and possibly also [C(6)Br(6)](+) exhibited Jahn-Teller-distorted geometries in the crystalline state. In the case of C(6)F(6)(+)Sb(2)F(11)(-), two low-symmetry geometries were observed in the same crystal. Interestingly, the structures of the cation radicals 2,4,6-[C(6)H(3)F(3)](+) and C(6)I(6)(+) did not exhibit Jahn-Teller distortions. DFT calculations showed that the explanation for the lack of distortion of these cations from the D(3h) or D(6h) symmetry of the neutral benzene precursor was different for 2,4,6-[C(6)H(3)F(3)](+) than for [C(6)I(6)](+).

20.
Angew Chem Int Ed Engl ; 51(2): 419-22, 2012 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-22128073

RESUMO

Joining the stable: The first examples of the highly instable selenenyl fluorides RSeF are prepared from the reaction on the tin selenide RSeSnMe(3) with XeF(2). Through the use of extremely large protecting groups (m-terphenyl ligands) which stabilizes the RSeF units against disproportionation, the compounds could be isolated and characterized by NMR spectroscopy and single-crystal structure analysis (see structure).

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