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1.
Asymmetrically Substituted Iminium Salts [Et3PNAsPh3]X and their Reactions with Acetonitrile. Crystal Structures of [Et3PNAsPh3]X (X = Cl, Br), [(Ph3As)2CCN]Br, and [(Ph3As)2CCN(SnBr5)] The asymmetrically substituted iminium salts [Et3PNAsPh3]X with X = Cl, Br are formed in the reaction of Me3SiNPEt3 with Ph3AsX2 at 180 °C in the melt. The products crystallize from acetonitrile as colourless, moisture-sensitive crystals, which crystallize isotypicly in the space group P21/c with four formula units in the unit cell. In the cations short PN distances of 159.7 pm and short AsN distances of 172.7 pm are to be found along with PNAs bond angles of 135.8°. With acetonitrile they react in the presence of potassium hydride forming the acetonitrile derivatives [(Ph3As)2CCN]X. The crystal structure analysis of the bromide shows an ionic structure with a linear CCN group of the cation and an As–C–As bond angle of 126.9°. [(Ph3As)2CCN]Br reacts with tin tetrabromide to form the complex [(Ph3As)2CCN(SnBr5)] with a zwitterionic structure and a bond angle CNSn of 144.0°.  相似文献   

2.
Phosphonium Salts with Hydrogen Dihalide Anions HCl2?, HBr2?, HI2?, or HBrCl? Phosphonium hydrogen dihalides [R3PR′][XHY] (X = Y = Cl, Br, I; X = Br, Y = Cl) resp. [R3PH]HBr2 are obtained as extremely hydrolyzable crystals by reaction of phosphonium halides or tertiary phosphanes with hydrogen halide. According to IR spectroscopic results the solid compounds mostly contain anions [XHX]? with symmetric hydrogen bonds. In solution 1H NMR measurements show a slight (X = Cl, Br) or considerable (X = I) dissociation according to HX2? ? X? + HX. On heating the solid compounds decompose with formation of hydrogen halide and [R3PR′]X or [R3PH]X. In this process the hydrogen bromidechlorides [R3PR′][BrHCl] exclusively eliminate HCl. NMR studies (1H und 31P) with solutions containing [R3PH]HBr2 (R = phenyl, 1-naphtyl) or HBr and Ph3P in varying molar ratios show that a fast proton exchange between the competing Lewis bases R3P and Br? exists.  相似文献   

3.
Inhaltsübersicht. Die Reaktion von Difluorhalogenmethanen, CF2X2, mit Phosphanen, R3P, in Gegenwart von Metallen und Carbonylverbindungen, R″R′CO, führt zur Bildung geminaler Difluorolefine, R″R′C=CF2. Die sorgfältige Untersuchung der Einzelschritte dieser komplexen Reaktion zeigt, daß intermediär Difluorhalogenmethylphosphoniumhalogenide, [R3P–CF2X]X, und Difluormethylenphosphorane, R3P – c??-F2, gebildet werden. Die Phosphoniumsalze sind stabil und können als kristalline Substanzen isoliert werden. Durch Metalle oder Phosphene werden sie zu den instabilen Difluormethylenphosphoranen reduziert. Diese zersetzen sich beim Fehlen geeigneter Reaktionspartner in Phosphan und Difluorcarben, CF2. Ihre Bildung durch Addition von CF2 an R3P ist nicht möglich. Mit Halogenwasserstoffen bilden sie Difluormethylphosphoniumsalze, [R3P-CHF2]X. Formation and Stability of Difluoromcthylene Phosphoranes, R3P —c?F2 In the presence of metals and carbonyl compounds, R″R′CO, the reaction of difluoro-halomethanes, CF2X2, with phosphanes, R3P, leads to the formation of geminal difluoroolefins, R″R′C=CF2. Our investigations have proved that difluorohalomethylphosphonium halides, [R3P–CF2X]X, and difluoromethylene phosphoranes, R3P–C??F2, are formed intermediately. The phosphonium salts are stable. They can be isolated as crystalline substances. They are reduced by metals or phosphanes forming unstable difluoromethylene phosphoranes as intermediates. These decompose into phosphane and difluorocarbene, CF2, if suitable reactants are absent. Their reaction with hydrogen halides, HX, yields difluoromethylphosphonium salts, [R3P–CHF2]X. The formation of difluoromethylene phosphoranes by addition of CF2 to R3P is not possible.  相似文献   

4.
Structural Chemistry of the Alkyl- and Arylhaloarsenates(III) [Me2As2Cl5], [RAsCl3], [R2As2Br6]2– (R = Me, Et, Ph) and [Ph2AsX2] (X = Cl, Br) The alkyl- and arylhaloarsenates(III) [Ph4P][Me2As2Cl5] ( 1 ), [Ph4P][RAsCl3] (R = Me, Et, Ph, 2 – 4 ), [Me3PhN][PhAsCl3] ( 5 ), [Ph4P]2[R2As2Br6] (R = Me, Et, Ph, 6 – 8 ), [n-Pr4N][Ph2AsCl2] ( 9 ) and [n-Bu4N][Ph2AsBr2] ( 10 ) have been prepared and their structures established by X-ray diffraction. In contrast to the chloroarsenates(III) 2 – 5 , which all contain isolated ψ-trigonal bipyramidal anions [RAsCl3], the analogous bromoarsenates(III) 6 – 8 exhibit dimeric structures. Whereas the trans sited As–Cl distances in 2 and 3 are very similar a pronounced degree of asymmetry is apparent for the Cl–As–Cl three-centre bonds in 4 and 5 [2.396(1) and 2.602(1) Å in 5]. In 6 and 7 Ci symmetry related RAsBr2 units are connected through long As…Br bonds [2.926(1) and 3.116(2) Å in 6 ]. The bromophenylarsenate(III) anion of 8 which contains two effectively undistorted ψ-trigonal bipyramids [PhAsBr3] associated by weak As…Br interactions [3.117(2) Å]. In view of its very long bridging As…Cl distances the [Me2As2Cl5] anion in 1 can, as 6 an 7 , be regarded as two MeAsCl2 molecules weakly linked through a chloride ion.  相似文献   

5.
On the Reaction of Trifluorohalomethanes with Phosphanes The reactions of trifluorohalomethanes CF3X (X = Cl, Br, I) with Ph3P, Bu3P, (Me2N)3P, and (Et2N)3P were investigated. CClF3 does not react. In the reactions of CBrF3 and CF3I with Bu3P in acetonitrile trifluorophosphonium salts, [Bu3PCF3]X (X = Br, I), are formed, whereas gaseous CF3I and Bu3P yield Bu2PCF3. Depending on the reaction conditions the aminophosphanes form either [(R2N)3PX]X (R = Me, Et; X = Br, I) and CF3H or [(R2N)3PCF3]X.  相似文献   

6.
Azido Beryllates with Adamantan‐like Structures: Synthesis, IR Spectra, and Crystal Structures of (Ph4P)2[Be4X4(μ‐N3)6] (X = Cl, Br) The azido beryllates (Ph4P)2[Be4X4(μ‐N3)6] (X = Cl 1a , X = Br 1b ) have been prepared by the reaction of Me3SiN3 with the halogeno beryllates (Ph4P)2[Be2Cl6] and (Ph4P)2[Be2Br6], respectively, in CH2Cl2 and CH2Br2 solution, respectively. Both complexes form moisture sensitive, colourless crystals, which are nonexplosive with respect to mechanical or thermal stress. They are characterized by IR spectroscopy and by crystal structure determinations. 1a and 1b crystallize isotypically in the space group C2/c with 12 formula units per unit cell. Whereas 1a was only refined to R1 = 0.13, which is caused by disordering, 1b could be refined to R1 = 0.066. The structures contain adamantanlike dianions [Be4X4(μ‐N3)6]2— with two symmetry nonequivalent individuals which differ only slightly from one another. The Be4N6 core is formed by bridging function of the α‐nitrogen atoms of the azide groups with BeN bond lengths of 172.5 and bond lengths Nα—Nβ = 123.2 pm and Nβ—Nγ = 113.1 pm on average in the structure of 1b .  相似文献   

7.
Synthesis, Crystal Structures, and Vibrational Spectra of trans ‐[Pt(N3)4X2]2–, X = Cl, Br, I By oxidative addition to (n‐Bu4N)2[Pt(N3)4] with the elemental halogens in dichloromethane trans‐(n‐Bu4N)2[Pt(N3)4X2], X = Cl, Br, I are formed. X‐ray structure determinations on single crystals of trans‐(Ph4P)2[Pt(N3)4Cl2] (triclinic, space group P1, a = 10.352(1), b = 10.438(2), c = 11.890(2) Å, α = 91.808(12), β = 100.676(12), γ = 113.980(10)°, Z = 1), trans‐(Ph4P)2[Pt(N3)4Br2] (triclinic, space group P1, a = 10.336(1), b = 10.536(1), c = 12.119(2) Å, α = 91.762(12), β = 101.135(12), γ = 112.867(10)°, Z = 1) and trans‐(Ph4P)2[Pt(N3)4I2] (triclinic, space group P1, a = 10.186(2), b = 10.506(2), c = 12.219(2) Å, α = 91.847(16), β = 101.385(14), γ = 111.965(18)°, Z = 1) reveal, that the compounds crystallize isotypically with octahedral centrosymmetric complex anions. The bond lengths are Pt–Cl = 2.324, Pt–Br = 2.472, Pt–I = 2.619 and Pt–N = 2.052–2.122 Å. The approximate linear Azidoligands with Nα–Nβ–Nγ‐angles = 172.1–176.8° are bonded with Pt–Nα–Nβ‐angles = 116.2–121.9°. In the vibrational spectra the platinum halogen stretching vibrations of trans‐(n‐Bu4N)2[Pt(N3)4X2] are observed in the range of 327–337 (X = Cl), at 202 (Br) and in the range of 145–165 cm–1 (I), respectively. The platinum azide stretching modes of the three complex salts are in the range of 401–421 cm–1. Based on the molecular parameters of the X‐ray determinations the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are fd(PtCl) = 1.90, fd(PtBr) = 1.64, fd(PtI) = 1.22, fd(PtNα) = 2.20–2.27 and fd(NαNβ, NβNγ) = 12.44 mdyn/Å.  相似文献   

8.
[NiL2X2] or [HL][NiLX3] – Reaction of Sterically Demanding Trialkylphosphines L with NiX2 (X = Cl, Br) in Ethanol The reaction of some sterically demanding trialkylphosphines L = PR2R′ (R = iPr, R′ = tBu; R = tBu, R′ = iPr, Me) with NiX2 (X = Cl, Br) in ethanol affords instead of the expected non-electrolytes [NiL2X2] tertiary phosphonium nickelates [HL][NiLX3] due to participation of the solvent. In case of the less bulky PtBu2Me both complex types were obtained. [Ni(PtBu2Me)2Cl2] is tetrahedral and therefore one of the two examples of paramagnetic bis(trialkylphosphine)dihalogenonickel(II) complexes known so far. In solution the latter compound undergoes an equilibrium of tetrahedral (paramagnetic) and planar (diamagnetic) conformer. Vis spectra as well as the results of magnetic measurements and 1H and 31P NMR investigations are reported.  相似文献   

9.
N,N′-Dimethylthioharnstoff-Komplexe des Zn, CdII und HgII Komplexe des N,N′-Dimethylthioharnstoffs (DMTU) mit Zn–, CdII-und HgII-Halogeniden des Typs M(DMTU)2X2 und [HgDMTUX2]2 (X ? Cl, Br, J) wurden dargestellt und IR-spektroskopisch (4000-60cm?1) sowie durch Leitfähigkeitsmessungen untersucht. Die Molekulargewichte einiger dieser Komplet in Nitrobenzol werden angegeben. Die 1:2-Komplexe Zn(DMTU)2X2, Cd(DMTU)2X2 (X ? Cl, Br, J) und Hg(DMTU)2J2 sind tetraedrisch, während die Komplexe Hg(DMTU)2X2 (X ? Cl, Br) eine pseudooktaedrische Halogen-verbrückte Konfiguration zu haben scheinen. Die 1:1 HgII-Komplexe [HgDMTUX2]2 (X ? Cl, Br, J) haben im festen Zustand eine dimere tetraedrische Halogen-verbrückte Struktur. In allen diesen Komplexen ist N,N′-Dimethylthioharnstoff über den Schwefel am Metall gebunden.  相似文献   

10.
Preparation of Halogeno Pyridine Rhenates(III), [ReX6?n(Py)n](3?n)? (X = Br, Cl; n = 1?3) Crystal Structures of trans-[(C4H9)4N][ReBr4(Py)2], mer-[ReCl3(Py)3], and mer- [ReBr3(Py)3] The mixed halogeno-pyridine-rhenates(III), [ReX6?n(Py)n](3?n)? (X = Br, Cl), n = 1?3, have been prepared for the first time by reaction of the tetrabutylammoniumsalts (TBA)2[ReX6] (X = Br, Cl) in pyridine with (TBA)BH4 and separation by chromatography on Al2O3. Apart from the monopyridine complexes only the trans and mer isomers are formed from the bis-and tris-pyridine compounds. The X-ray structure determinations of the isotypic neutral complexes mer- [ReX3(Py)3] (monoclinic, space group P 21/n, Z = 4; for X = Cl: a = 9,1120(8), b = 12,5156(14), c = 15,6100(13) Å, β = 91,385(7)°; for X = Br: a = 9,152(5), b = 12,852(13), c = 15,669(2) Å, β = 90,43(2)°) reveal, due to the stronger trans influence of pyridine compared with Cl and Br, that the Re? X distances in asymmetric Py? Re? X3 axes with ReCl3 = 2,397 Å and ReBr3 = 2,534 Å are elongated by 1,3 and 1% in comparison with symmetric X1? Re? X2 axes with ReCl1 = ReCl2 = 2,367 Å and ReBr1 = 2,513 and ReBr2 = 2,506 Å, respectively. The Re? N bond lengths are roughly equal with 2,12 Å. Trans-(TBA)[ReBr4(Py)2] crystallizes triclinic, space group P1 , a = 9,2048(12), b = 12,0792(11), c = 15,525(2) Å, α = 95,239(10), β = 94,193(11), γ = 106,153(9)°, Z = 2. The unit cell contains two independent but very similar complex anions with approximate D2h(mmm) point symmetry.  相似文献   

11.
Ionic compounds, [Q] [R2SnX(dmit)][dmit=1,3-dithiole-2-thione-dithiolate; Q=1,4-dimethylpyridinium or tetraalkylammonium; R=Phor alkyl; X=Cl, Br, I, NCS, NCSe, or N3] have been obtained by (a) from R2SnX2 and [Q]2[Zn(dmit)2] in the presence of excess QX,(b) from halide exchange reactions in acetone solution between [Q] [R2SnCl(dmit)]and a halide or pseudohalide source, or (c) by addition of QX to [R2Sn(dmit)]. Crystalstructure determinations of [NEt4] [Ph2SnI(dmit)] and [1,4-Me2pyridiniuml [Ph2SnBr(dmit)] as well as of the mixed halides, [1a, 1b, 4a, 2] [Ph2SnClnI1−n(dmit)] (n=0.57, 0.42 or0.22), indicated that the tin atoms have distorted trigonal bipyramidal geometries in the anions,with the X ligand and a dithiolato atom in the axial sites. The [R2SnX(dmit)] anions remain essentially intact in organic solvents, but lose X on extractionwith H2O to give the neutral species, R2Sn(dmit).  相似文献   

12.
Abstract

The interaction of the complexes (Et4 N)[Pt(R2 SO)X3] (R = Me, Et, CH2 Ph, X [dbnd] C1; R [dbnd] Me, X [dbnd] Br) and cis-[Pt(Me2 SO)2 Cl2] with concentrated HX (X [dbnd] Cl. Br) results in the reduction of the coordinated sulfoxides and oxidation of Pt(II) to Pt(IV). As a result [Pt(R2 S)X5 and [Pt(R2S)2 X4] are formed. Ligands R2 S can be removed from the complexes and isolated in a free state.  相似文献   

13.
The halopentacarbonylmetal compounds of molybdenum and tungsten react with phosphines in polar aprotic solvents with CO substitution to give the ionic derivatives [LM(CO)4X]? (X = Cl, Br; M = Mo, W; L = i-PrnPh3?nP, (Me2N)nPh3?nP, (i-PrO)nPh3?nP, Ph2MeP, Et3P, (PhO)3P, n = 0, 1, 2, 3). The substitution of the halide ligand, which is catalysed by protic solvents, provides a convenient route to the neutral complexes LM(CO)5 and LL′M(CO)4 (L = phosphines; L′ = ammonia, acetonitrile, pyridine, piperidine). cis-(NH3)(i-Pr3P)W(CO)4 in solution is slowly deuterated by D2O. In this reaction all three hydrogen atoms appear to be exchanged simultaneously.  相似文献   

14.
Concerning the Influence of the Substituents R = Ph, NEt2, iPr, and tBu in Triphosphanes (R2P)2P? SiMe3 and Phosphides Li(THF)2[(R2P)2P] on the Formation and Properties of Phosphino-phosphinidene-phosphoranes The triphosphanes X2P? P(SiMe3)? PY2 5, 7, 9, 11, 13 and the derived phosphides Li(THF)2[X2P? P? PY2] 6, 8, 10, 12, 14 were synthesized: 5 and 6 with X2 = iPr2 and Y2 = tBu2, 7 and 8 with X2 = Y2 = PhtBu, 9 and 10 with X2 = tBu2 and Y2 = Ph2, 11 and 12 with X2 = Y2 = Ph2, and 13 and 14 with X2 = tBu2 and Y2 = (NEt2)2. The silylated triphosphanes at ?70°C in toluene with CBr4 may yield X2P? P?P(Br)Y2 and X2P? P(Br)? PY2, and the lithiated phosphides with MeCl may yield X2P? P?P(Me)Y2 and X2P? P(Me)? PY2 depending on X and Y. The bromiated product of 5 (X2 = iPr2, Y2 = tBu2) is the ylide iPr2P? P?P(Br)tBu2, and the methylated derivatives of 6 are both iPr2P? P?P(Me)tBu2, tBu2P? P?P(Me)iPr and the methylated triphosphane. Ph2P? P?P(Br)tBu2 as well as the brominated triphosphane are obtained from 9 (X2 = tBu2, Y2 = Ph2), and similarly Ph2P? P?P(Me)tBu2 and the methylated triphosphane from 10 . Compound 14 (X2 = tBu2, Y2 = (NEt2)2 gives rise to the brominated ylide tBu2)P? P?P(Br) · (NEt2)2 and to the brominated triphosphane, and on methylation to tBu2P? P?P(Me)(NEt2)2 and to tBu2P? P(Me)? P · (NEt2)2 (main product). The Br substituted derivatives decompose already on warming to ?30°C, while the methylated compounds are stable up to 20°C.  相似文献   

15.
The Staudinger reaction of organic azides tBuN3, 1‐Ad‐N3, and DippN3 (Dipp = 2,6‐diisopropylphenyl) with (R)‐N,N′‐bis(diphenylphosphanyl)‐2,2′‐diamino‐1,1′‐binaphthyl [(R)‐Binam‐P], obtained by an optimized procedure from (R)‐(+)‐Binam, Ph2PCl, and Et3N in DCM, leads to preparation of a series of new C2‐symmetric bis‐iminophosphonamide ligands [(R)‐Binam(Ph2PN(H)R)2] [R = tBu ( 1 ), Ad ( 2 ), and Dipp ( 3 )]. The molecular structure of 1· 2DMSO was confirmed by X‐ray structure analysis.  相似文献   

16.
Synthesis and Crystal Structures of (Ph3PNPPh3)2[Re2Br10] and (Ph4P)[Re2Br9] Depending on the molar ratio by reaction of [n-Bu4N]2[ReBr6] with the Lewis acid BBr3 in dichloromethane the bioctahedral complexes [n-Bu4N]2[Re2Br10] and [n-Bu4N][Re2Br9] are formed. The X-ray structure determination on (Ph3PNPPh3)2[Re2Br10] (monoclinic, space group C 2/c, a = 20.007(4), b = 15.456(5), c = 24.695(4) Å, β = 107.53(2)°, Z = 4) reveals a centrosymmetric edge-sharing complex anion with approximate D2h symmetry and mean terminal and bridging Re–Br bond lengths of 2.453 (equatorial), 2.482 (axial) and 2.591 Å, respectively, and a Re–Re distance of 3.880 Å. (Ph4P)[Re2Br9] (triclinic, space group P 1, a = 11.062(2), b = 12.430(3), c = 13.163(5) Å, α = 72.94(2), β = 68.47(2), γ = 82.09(2)°, Z = 2) contains a confacial bioctahedral anion with nearly D3h symmetry and mean terminal and bridging Re–Br distances of 2.460 and 2.536 Å, respectively, and a Re–Re distance of 2.780 Å.  相似文献   

17.
Cyclocondensations with Primary Sulfinimidamides: Synthesis of Six-membered Rings with λ4-Thiadiazine and λ4-Thiatriazadiphosphorine Constitution 1,1-Dimethyl-ethanesulfinimidamide ( 1 ,) reacts with tetracyanoethylene by elimination of hydrogen cyanide to give the 1,2,6-thiadiazine 2 . In the cyclocondensation reaction of 1 , with tetrachloromethane and phosphines Ph2PR′ (R′ = Ph2PNH or Ph) the 1,2,4,6,3,5-thiatriazaphosphorine 3 a , and the ring-open compound [t-BuS(NH)NHPPh3]Cl ( 4 ,), respectively, are formed by P? N-bond formation. The compounds are characterized by IR, MS and NMR data, and for 3a , further by X-ray structure analysis (space group P1 , Z = 2).  相似文献   

18.
Crystal Structure of Ph3PNBr · Br2 Ph3PNBr · Br2 ( 1 ) has been prepared besides of other products from the reaction of Ph3PNH with bromine, forming orange‐yellow single crystals which are characterized by IR‐spectroscopy and by a crystal structure determination. Space group P21/n, Z = 4, lattice dimensions at 20 °C: a = 916.76(10), b = 1351.42(8), c = 1494.9(2) pm, β = 96.191(5)°, R1 = 0.0538. 1 has a molecular structure in which the Br2 molecule is coordinated at the nitrogen atom of the N‐bromine‐phosphoraneimine Ph3PNBr in a linear arrangement N–Br–Br with bond lengths N–Br of 224.5(6) pm and Br–Br of 248.4(1) pm. The nitrogen atom of 1 is ψ‐tetrahedrally coordinated in addition by the phosphorus atom with a P–N distance of 165.3(6) pm and by the covalently bonded bromine atom with a bond length of 188.9(6) pm.  相似文献   

19.
Reaction of N-Trimethylmetal(IVb) Trialkylphosphine Imines with Hydrogen Halides Investigations of the reaction of N-trimethylmetal(IVb)-substituted phosphine imines with hydrogen have been carried out. With one mole of HX phosphonium halides of the general formula [R3P? NH? MMe3]X? (R = CH3, C2H5; M = Si, Ge, Sn; X = Cl, Br, J) are obtained. A second mole of HX causes M? N bond cleavage, yielding aminophosphonium halides, [R3P? NH2]X?.  相似文献   

20.
Complexes
(M = Rh, X = Cl, M = Ir, X = Cl, Br, I and R = CH3, R′ = CH3, p-tolyl) have been made by the reaction of (Ph3P)2(CO)MX with
. The proposed structure is analogous to that of the related copper derivatives and contains a five-membered ring in which an MI to AgI donor bond is bridged by an azenido group, while the halide atom X has migrated from MI to AgI.Carbon monoxide at 1 atm reacts rapidly and quantitatively with the iridium compounds to give novel acyltriazenido compounds {Ph3P(CO)2 - Ir[OCN(R)N=NR′]} (R = CH3, p-tolyl; R′ = CH3, p-tolyl).  相似文献   

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