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1.
Formation and Structures of Chromium Carbonyl Complexes of Tris(trimethylsily)heptanortricyclane (Me3Si)3P7 (Me3Si)3P7 1 reacts with one equivalent of Cr(Co)5THF 2 to give the yellow (Me3Si)3P7[Cr(Co)5] 4. The Cr(Co)5group is attached to a Pe atom. Yellow (Me3Si)3P7[Cr(CO)5]2 5 is obtained either from reacting 1 with two equivalents of 2 , or from 4 with one equivalent of 2. One Cr(CO)5 groups in 5 is coordinated to a Pe atom, the other one to a P,b atom. Similarly, Yellow (Me3Si)3P7[Cr(CO)5]3 6 results from reacting 5 with one equivalent of 2 . Two Cr(CO)5 groups in 6 are linked to Pb atoms, and the third one either to a Pe or the Pa atom (assignment not completely clear). Derivatives containing a Pe bridge appear in reactions of 1 with higher amounts of 2 . Such, 5 forms mixtures of the red compounds (Me3Si)3P7 × [Cr(CO)5]2[Cr(CO)4] 8 and (Me3Si)3P7[Cr(CO)5] × [Cr(CO)4] 9 , and even preferably 9 with four equivalents of 2 . In 8 , one Cr(CO)5 group is attached to that pe atom which is not engaged in the Cr(CO)4 bridge, and the second to one of the Pb atoms directly adjacent to the bridge. The additional Cr(CO)5 group in 9 is coordinated to the remaining Pb atom directly adjacent to the bridge. In reactions of 5 with even higher amounts of 2 , four Cr(CO)5 groups and one Cr(CO)4 bridge attach to the basic P7 skeleton to from the less stable Me3P7[Cr(CO)5]4[Cr(CO)4]. (Me3Si)3P7 1 reacts considerably slower with Cr(CO)5THF 2 than R3P7 (R = Et, iPr). Cr(CO)4NBD 3 reacts with 1 , but it was not possible to isolate (Me3Si)3P7[Cr(CO)4]. However, 4 with 3 forms (Me3Si)3P7[Cr(CO)5][Cr(CO)4] 7 , and 5 with 3 yields (Me3Si)3P7[Cr(CO)5]2[Cr(CO)4] 8 . The structures of 4 , 5 , 7 , 8 or 9 are quite analogous to those of the derivatives of Et3P7 but there exist significant differences in stability and reactivity. While Et3P7[Cr(CO)5]2 in solution rearranges to give the stable Et3P7[Cr(CO)5][Cr(CO)4], the analogous (Me3Si)3P7[Cr(CO)5][Cr(CO)4] 7 is not stable and is not obtained from (Me3Si)3P7[Cr(CO)5]2 5 . Et3P7[Cr(CO)5]3 can just be detected spectroscopically and rearranges easily to give Et3P7[Cr(CO)5]2 [Cr(CO)4] whereas (Me3Si)3P7[Cr(CO)5]3 6 can be isolated. These differences are caused by the greater steric requirements of Me3Si groups. The formation of a Pe–Cr(CO)4–Pe bridge, e.g., requires a Me3Si group in 1 to switch from the s to the as position. Whereas many of the complex compounds of R3P7 (R = Et, iPr) crystallize easily, the analogous derivatives of (Me3Si)3P7 did not yield crystals. The structures of the products were assigned by evaluating the coordination shift in their 31P NMR spectra and by comparision of these spectra with those of such derivatives of Et3P7 which previously had been investigated by single crystal structure determinations.  相似文献   

2.
The Phosphides LiR2P7, Li2RP7 (R = Me3Si, Et, iPr, iBu) as well as Mixed Alkylated and Silylated Heptaphosphanes(3) Formation and properties of LiR2P7 and Li2PR7 (R = Me3Si, Et, iPr, iBu) and their reactions with Me3SiCl or alkylhalides yielding mixed alkylated and silylated heptaphosphanes(3) are reported. Reactions of (Me3Si)3P7 and Li3P7. 3 DME produce mixtures of Li(Me3Si)3P7, Li2(Me3Si)P7 and Li3P7 from which pure Li(Me3Si)2P7 (s, as) can be isolated by means of an extraction with toluene. Similarly, the isomers of LiR2P7 (R = Et, iPr, iBu) can be extracted from the mixtures obtained by reacting Li3P7 with alkylbromides. The (s) isomers of LiR2P7 in solution at about 20°C from the (as) isomers whereas the latter up to 70°C do not show any inversion. The (as) lithiumdialkylphosphides can be obtained as ether free products (red brown powder, isoluble in toluene, soluble in THF) by repeated addition of toluene and removal of the solvents; the (s) isomers decompose during the procure. In reactions of LiEt2P7. THF (s, as) in toluene at ?30°C with EtBr only the (s) isomer is substituted and gives Et3P7 (s), however on warming to 20°C by inversion of Pe a ratio of (s) : (as( = 1 : 3 is obtained. With Li(iBu)2P7, (s) reaction begins above ?20°C the giving both the (s) and the (as) isomer. (iBu)3P7 (s) is the prefered isomer at higher temperatures. Li(Me3Si)2P7 (s, as) with Me3SiCl exclusively yields (Me3Si)3P7 (s). Li2RP7 (R = alkyl, Me3SI) is not available. From mixtures with LiR2P7 and Li3P7, it can be isolated only after repeated cumbersome extraction of LiR2P7 as was shown with Li2(iPr)P7 as an example. Ether free LiEt2P7(s, as) with Me3SiCl exclusively gives Et2(Me3Si)P7 (s, as) whereas LiEt2P7 ? THF due to its THF content does not. Similarly, ether free Li(iBu)2P7 yields (iBu)2(Me3Si)P7 (s, as). The compounds R(Me3Si)2P7 (R = alkyl) cannot be selectively prepared neither starting from Li2RP7 with Me3SiCI) nor from Li(Me3Si)2P7 with RX. Such, the reaction of Li(Me3Si)2P7 ? THF with EtBr in toluene at ?78°C yield a mixture of Et(Me3Si)2P7 (42%), Et2(Me3Si)P7 (27010), (Me3Si)3P7 (29%) and Et3P7 (2%). (Me3Si)3P7 with MeI in a molar ratio of 1 : 1 at 70°C quantitatively produces Me(Me3Si)2P7 whereas already using a molar ratio of 1 : 2 also Me3P7 is obtained. With EtBr mixtures of Et(Me3Si)2P7 and Et3P7 are formed. iBuBr gives iBu3P7, but tBuBr does not yield any tBu3P7.  相似文献   

3.
Silylated Phosphaneimine Complexes of Chromium(II), Palladium(II), and Copper(II). The Crystal Structures of [CrCl2(Me3SiNPMe3)2], [PdCl2(Me3SiNPEt3)2], and [CuCl2(Me3SiNPMe3)]2 The title compounds have been prepared by the reaction of the silylated phosphaneimines Me3SiNPR3 (R = CH3, C2H5) with CrCl2(THF)2, PdCl2 and CuCl2, respectively, in dichloromethane suspensions. All donor-acceptor complexes were characterized by IR spectroscopy and by crystal structure determinations. [ CrCl2(Me3SiNPMe3 )2]: Space group Pccn, Z = 4, structure determination with 2104 observed unique reflections, R = 0.045. Lattice dimensions at ?70°C: a = 1326.3, b = 1562.5, c = 1171.5 pm. Within the monomeric molecular structure the chromium atom is planarly coordinated within the trans-configuration of the Cl atoms and the N atoms with distances of Cr? Cl = 235.94 pm and Cr? N = 211.7 pm. [ PdCl2(Me3SiNPEt3)2 ]: Space group P21/n, Z = 2, structure determination with 2412 observed unique reflections, R = 0.031. Lattice dimensions at 20°C: a = 917.3, b = 1390.2, c = 1161.7 pm, β = 95.80°. Within the monomeric molecular structure the palladium atom is planarly coordinated within the trans-configuration of the Cl atoms and the N atoms with distances of Pd? Cl = 222.9 pm and Pd? N = 209.5 pm. [ CuCl2(Me3SiNPMe3)2 ]: Space group Pbca, Z = 4, structure determination with 1861 observed unique reflections, R = 0.067. Lattice dimensions at ?70°C: a = 1440.2, b = 1205.1, c = 1536.5 pm. The compound forms centrosymmetric dimeric molecules, in which the Cu atoms are linked via almost symmetrical chloro-bridges with Cu? Cl distances of 231.4 pm. The distance Cu? N is 196.7 pm.  相似文献   

4.
The Crystal Structure of Me3SiI · β-Picoline and Me3SiI · γ-Picoline A Comparison between the Lewis-Bases Pyridine, β-Picoline, and γ-Picoline The reaction of Iodinetrimethylsilane with β- und γ-Picoline (Pic) leads to solid 1 : 1 compounds Me3SiI · β-Picoline 1 , Me3SiI · γ-Picoline 2. The reaction was performed at room temperature. Yellow single crystals were obtained by sublimation. Single crystal X-ray investigations confirm that both compounds are ionic [Me3SiPic]+I?. The comparison of β-Picoline with γ-Picoline and Pyridine (Py) demonstrates that the presence of a methyl group and also its position has no significant influence on the Si? N bond length in compound 1, 2 and on the adduct Me3SiI · Py.  相似文献   

5.
Crystal Structure of N,N′-Bis(trimethylsilyl)-imidazoliumiodide [(Me3Si)2(C3H3N2)]+I? Me3SiI forms with N-Trimethylsiylimidazole (NTMSI) a 1:1 compound which is stable at room temperature. Single crystals can be isolated from a solution of chloroform. The X-ray crystal structure investigation proves an ionic structure.  相似文献   

6.
Preparation and Crystal Structure of [(Me3SiCH2)2InP(H)Ad]2 Reaction of (Me3SiCH2)3 In with AdPH2 (Ad = adamantyl) in the presence of AgNO3 leads to [(Me3SiCH2)2InP(H)Ad]2 1 in 30% yield. The crystal structure of 1 is discussed.  相似文献   

7.
Crystal Structures of the Silylated Phosphaneimines Me3SiNP(c-C6H11)3 and (Me3SiNPPh2)2CH2 The crystal structures of Me3SiNP(c-C6H11)3 ( 1 ) and (Me3SiNPPh2)2CH2 ( 2 ) are determined by X-ray diffraction at single crystals. In both compounds the PN distances correspond to double bonds, the SiN distances to single bonds. With 149.8° the SiNP bond angle in 1 is noticeably large, while it is only 138.5° in 2 , which shows C2 symmetry. 1 : Space group P21/n, Z = 4, lattice dimensions at –70 °C: a = 1143.0(1), b = 1743.0(2), c = 1152.5(1) pm, β = 90.42(1)°; R = 0.0677. 2 : Space group I41/a, Z = 8, lattice dimensions at –60 °C: a = b = 1959.7(1), c = 1695.8(1) pm, R = 0.0433.  相似文献   

8.
The reaction of AgSCN with (Me3PhN)3[Fe(NCS)6] in DMF yields two‐dimensional polymeric, heteronuclear complexes (Me3PhN)2[Ag2Fe(SCN)6] ( 1 ) and (Me3PhN)6[Ag6Fe3(SCN)18] · CH2Cl2·DMF ( 2a ) with bridging SCN? ligands, whereas additional (Me3PhN)(SCN) leads to (Me3PhN)4[Ag2Fe(SCN)8] ( 3 ) with a one‐dimensional structure. The selenocyanato complex 2b , homologous to 2a , could also be prepared. Single crystal X‐ray structure determinations show, that the Ag+ ions in 1 and 2a are coordinated tetrahedrally by four S atoms, in 3 by one N and three S atoms of the bridging SCN? ligands; six N atoms of the SCN? or SeCN? ligands bind to Fe2+ in an octahedral arrangement.  相似文献   

9.
Synthesis and Crystal Structure of the Aminoiminophosphinate Copper(I) Complex [Cu(Me3SiNP(Ph)2NSiMe3)]2 The title compound 1 was prepared by the reaction of Me3SiNP(Ph)2N(SiMe3)2 with copper(I) chloride at 120 °C to give colourless crystals which were characterized by a crystal structure determination. Space group C2/c, Z = 4, lattice dimensions at 193 K: a = 1854.0(3), b = 1256.2(3), c = 1969.9(3) pm, β = 106.30(2)°; R1 = 0.063. 1 forms dimeric molecules with a nonplanar Cu2N4P2 eight‐membered ring of symmetry C2 and a rather long Cu…Cu distance of 262.1(1) pm.  相似文献   

10.
Facile Syntheses of Alkylaluminium and Alkylgallium Hydrides – Crystal Structures of [(Me3C)2GaH]3 and the Novel Sesquihydrides [(Me3C)2EH]2[EH2CMe3]2 (E = Al, Ga) The facile syntheses of some important, sterically highly shielded dialkylaluminium hydrides R2AlH [R = CMe3, CH(SiMe3)2] succeeded by the reaction of the corresponding trialkylaluminium compounds with the alane adduct AlH3 × NMe2Et in a 2 to 1 molar ratio. This route is not suitable for the synthesis of monoalkylaluminium dihydrides. An excess of AlH3 yielded the novel sesquihydride [(Me3C)2AlH]2[AlH2CMe3]2 ( 3 ) as the hydride richest compound which possesses an unprecedented heterocycle comprising four aluminium and four hydrogen atoms in the solid state. The dialkylgallium hydride (Me3C)2GaH ( 4 ) was formed on a similar route by the treatment of tri(tert‐butyl)gallane with the adduct GaH3 · NMe2Et. As shown by a crystal structure determination, compound 4 is a trimer in the solid state possessing a Ga3H3 heterocycle. A gallium sesquihydride analogous to compound 3 , [(Me3C)2GaH]2[GaH2CMe3]2 ( 5 ), was formed on employing an excess of GaH3.  相似文献   

11.
[(Me3PN)3SNS(NPMe3)2]Cl2, a Mixed Valenced Phosphorane Iminato Complex of Sulfur The title compound has been prepared from trithiazyl chloride and the silylated phosphaneimine Me3SiNPMe3 in acetonitrile solution, forming red crystals, which were characterized by IR spectroscopy and by a crystal structure determination. Space group P21/c, Z = 4, structure solution with 4250 independent reflections, R = 0.054. Lattice dimensions at 20°C: a = 1077.8, b = 2036.6, c = 1480.5 pm, β = 102.39°. The compound consists of dications [(Me3PN)3SNS(NPMe3)2]2+ and chloride ions. In the cations the sulfur atoms of oxidation number +VI and +IV are connected by an asymmetric, bent nitrido bridge with SN bond lengths of 156.9 and 167.0 pm.  相似文献   

12.
Transition Metal Complexes of P-rich Phosphanes and Silylphosphanes. VII Carbonyl Complexes of the Heptaphosphane(3) iPr2(Me3Si)P7 From the reaction of iPr2(Me3Si)P7 1 with one equivalent of Cr(CO)5THF the yellow products iPr2(H)P7[Cr(CO)5] 2 and iPr2(Me3Si)P7[Cr(CO)5] 3 were isolated by column chromatography on silicagel. The P? H group in 2 results from a cleavage of the P? SiMe3 bond during chromatography. The Cr(CO)5 group in 2 is linked to an iPr? Pe atom, in 3 to the Me3Si? Pe atom of the P7 skeleton. The substituents do not force the formation of a single isomer; nevertheless 3 ist considerably favoured as compared to 2 . From the reaction of 1 with 2 equivalents of Cr(CO)5THF the yellow iPr2(H)P7[Cr(CO)5]2 4 was isolated bearing one Cr(CO)5 group at an iPr? Pe atom, the other one at a Pb atom of the P7 skeleton. Compound 3 yields with Cr(CO)4NBD the red iPr2(Me3Si)P7[Cr(CO)5][Cr(CO)4] 5 . Three isomers of 5 appear. Two Pe atoms of 5 are bridged by the Cr(CO)4 group, the third Pe atom is linked to the Cr(CO)5 ligand. iPr2(H)P7[Fe(CO)4] was isolated from the reaction of 1 with Fe2(CO)9. 31P NMR and MS data are reported.  相似文献   

13.
Synthesis and Structure of Phosphinophosphinidene-phosphoranes tBu2P? P?P(Me)tBu2 1, tBu(Me3Si)P? P?P(Me)tBu2 2, and tBu2P? P?P(Br)tBu2 3 A new method for the synthesis of 1 and 2 (Formulae see ?Inhaltsübersicht”?) is reported based on the reaction of 5 with substitution reagents (Me2SO4 or CH3Cl). The results of the X-ray structure determination of 1 and 2 are given and compared with those of 3 . While in 3 one P? P distance corresponds to a double bond and the other P? P distance to a single bond (difference 12.5 pm) the differences of the P? P distances in 1 and 2 are much smaller: 5.28 pm in 1 , 4.68 pm in 2 . Both 1 and 2 crystallize monoclinic in the space group P21/n (Z = 4). 2 additionally contains two disordered molecules of the solvent pentane in the unit cell. Parameters of 1 : a = 884.32(8) pm, b = 1 924.67(25) pm, c = 1 277.07(13) pm, β = 100.816(8)°, and of 2 : a = 1 101.93(12) pm, b = 1 712.46(18) pm, c = 1 395.81(12) pm, β = 111.159(7)°, all data collected at 143 K. The skeleton of the three P atoms is bent (PPP angle 100.95° for 1 , 100.29° for 2 and 105.77° for 3 ). Ab initio SCF calculations are used to discuss the bonding situation in the molecular skeleton of the three P atoms of 1 and 3 . The results show a significant contribution of the ionic structure R2P? P(?)? P(+)(X)R2. The structure with (partially) charged P atoms is stabilized by bulky polarizable groups R (as tBu) as compared to the fully covalent structure R2P? P(X)? PR2.  相似文献   

14.
Syntheses and Structures of [ReNBr2(Me2PhP)3] and (Me2PhPH)[ fac ‐Re(NBBr3)Br3(Me2PhP)2] [ReNBr2(Me2PhP)3] ( 1 ) has been prepared by the reaction of [ReNCl2(Me2PhP)3] with Me3SiBr in dichloromethane. The bromo complex reacts with BBr3 under formation of [Re(NBBr3)Br2(Me2PhP)3] ( 2 ) or (Me2PhPH)[fac‐Re(NBBr3)Br3(Me2PhP)2] ( 3 ) depending on the experimental conditions. The formation of the nitrido bridge leads to a significant decrease of the structural trans influence of the nitrido ligand which is evident by the shortening of the Re‐(trans)Br bond from 2.795(1) Å in [ReNBr2(Me2PhP)3] to 2.620(1) Å in [fac‐Re(NBBr3)Br3(Me2PhP)2] and 2.598(1) Å in [Re(NBBr3)Br2(Me2PhP)3], respectively.  相似文献   

15.
Reactions of R4Sb2 (R = Me, Et) with (Me3SiCH2)3M (M = Ga, In) and Crystal Structures of [(Me3SiCH2)2InSbMe2]3 and [(Me3SiCH2)2GaOSbEt2]2 The reaction of (Me3SiCH2)3In with Me2SbSbMe2 gives [(Me3SiCH2)2InSbMe2]3 ( 1 ) and Me3SiCH2SbMe2. [(Me3SiCH2)2GaOSbEt2]2 ( 2 ) is formed by the reaction of (Me3SiCH2)3Ga with Et2SbSbEt2 and oxygen. The syntheses and the crystal structures of 1 and 2 are reported.  相似文献   

16.
Syntheses and Crystal Structures of the Phosphaneimine Complexes MCl2(Me3SiNPMe3)2 with M = Zn and Co, and CoCl2(HNPMe3)2 The molecular complexes MCl2(Me3SiNPMe3)2 (M = Zn, Co) have been prepared by the reaction of the dichlorides of zinc and cobalt with Me3SiNPMe3 in CH3CN and CH2Cl2, respectively, whereas the complex CoCl2(HNPMe3)2 has been prepared by the reaction of CoCl2 with NaF in boiling acetonitrile in the presence of Me3SiNPMe3. All complexes were characterized by IR spectroscopy and by crystal structure determinations. The complexes MCl2(Me3SiNPMe3)2 crystallize isotypically. ZnCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 2677 observed unique reflections, R = 0.024. Lattice dimensions at ?70°C: a = 1243.6; b = 1319.0; c = 1464.7 pm. CoCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 3963 observed unique reflections, R = 0,071. Lattice dimensions at ?80°C: a = 1236.3; b = 1317.4; c = 1457.6 pm. CoCl2(HNPMe3)2 · CH2Cl2: Space group Pbca, Z = 8, 1354 observed unique reflections, R = 0.055. Lattice dimensions at ?80°C: a = 1247.3; b = 998.4; c = 2882.4 pm. All complexes have monomeric molecular structures, in which the metal atoms are coordinated in a distorted tetrahedral fashion by the two chlorine atoms and by the nitrogen atoms of the phosphaneimine molecules.  相似文献   

17.
Neutral Thiolates and a Iodothiolate of Antimony(III). Crystal Structures of Sb(SC6H5)3, Sb(SC6H2Me3-2,4,6)3, and SbI(SC6H2Me3-2,4,6)2 The crystal structures of Sb(SC6H5)3 ( 1 ), Sb(SC6 · H2Me3-2,4,6)3 ( 2 ), and the novel compound SbI(SC6H2Me3-2,4,6)2 ( 3 ) have been determined by X-ray crystallography. In addition to the expected trigonal pyramidal coordination of antimony intermolecular interactions are observed for 1 (Sb … O: 363.3 pm) and 3 (Sb … S: 2 × 369.4 pm) but not for 2 . The reasons for these differences are discussed.  相似文献   

18.
Novel Syntheses of Me2SbX (X = Cl, I) and Crystal Structures of Me2SbI and [(Me3Si)2CH]2SbCl The crystal structures of Me2SbI (Me = CH3) and [(Me3Si)2CH]2SbCl have been determined by X‐ray methods. Both molecules are pyramidal. The Me2SbI molecules are associated to chains through short intermolecular Sb…I distances (366,7(1) pm) with linear I–Sb…I units (171,87(4)°) and bent Sb–I…Sb bridges (116,83(3)°).  相似文献   

19.
The structure of K3(Me4N)3[Co(CN)6]2·3H2O has been determined from three-dimensional X-ray diffraction data. The unit cell is formed by parallel layers of cobalt octahedra [CoC6] and potassium octahedra, [K(1)N5O(1)], separated byc/2. In each layer both types of octahedra are located alternatively. The [MeN4]+ tetrahedra are located in the cavities between the two layers of octahedra. The crystal structure of this compound is the first example of its type. TMC 2483  相似文献   

20.
[Me3SnVO3] and [(Me2Sn)4V2O9], two Organotin Vanadates with Novel 3D Network Structures Two new organotin vanadates [Me3SnVO3] ( 1 ) and [(Me2Sn)4V2O9] ( 2 ) have been prepared by the reaction of NH4VO3 with Me3SnBr and Me2SnBr2 resp. in agar gel. The structures of 1 and 2 have been determined by x‐ray crystallography at 220 K. 1 crystallizes monoclinic in the space group P21/c with a = 1335.6(2), b = 1144.4(2), c = 1118.8(2) pm, β = 113.54(2)°. 2 crystallizes orthorhombic in the space group Pnnm with a = 1257.6(2), b = 1345.4(2), c = 1323.1(1) pm. 1 consists of infinite metavanadate chains which are linked by Me3Sn+ cations. 2 exhibits a complex 3D‐ network structure with VO4 tetrahedra, Me2SnO3 trigonal bipyramides and Me2SnO4 octahedra linked by common oxygen atoms.  相似文献   

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