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1.
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   

2.
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   

3.
Transition Metal Complexes of P-rich Phosphanes and Silylphosphanes. IV. Formation and Structure of the Chromium Carbonyl Complexes of Tris(di-tert-butylphospha)heptaphosphanortricyclane (t-Bu2P)3P7 The reaction of (t-Bu2P)3P7 1 with Cr(CO)5 · THF in a molar ratio of 1:1 yields yellow crystals of (t-Bu2P)3P7[Cr(CO)5] 2 having the Cr(CO)5 group coordinated to a Pb atom (basal) of the three membered ring. With a molar ratio of 1:2 compounds 2 , (t-Bu2P)3P7[Cr(CO)5]2 3 , (t-Bu2P)3P7[Cr(CO)5][Cr(CO)4] 4 and (t-Bu2P)3P7[Cr(CO)4]2 5 were obtained. In 3 (yellow crystals) one Cr(CO)5 group is linked to a Pb atom, the other one to an exocyclic Pexo atom. On irradiation 3 loosing one CO group generates 4 (orange red crystals) with an unchanged Cr(CO)5 group linked to the Pb atom and a five membered chelate-like ring containing an apical Pa atom, two equatorial Pa atoms, one Pexo atom and the Cr atom of the carbonyl group. Compound 5 (orange red crystals) contains two such five membered rings. (t-Bu2P)3P7[Cr(CO)4]3 6 (red needles) is formed with Cr(CO)5 · THF in a molar ratio of 1 : 1. However, even with higher amounts of Cr(CO)5 · THF and after extended reaction times, only 6 is formed; no further Cr carbonyl group could be attached to the P skeleton. With Cr(CO)5 · NBD in a molar ratio of 1 : 1, (t-Bu2P)3P7[Cr(CO)4] 7 is produced from 1, and 5 with a molar ratio of 2 : 1. As in 4, the Cr(CO)4 group in 7 (orange crystals) participates in a five membered chelate-like ring. It was not possible to generate 6 from 5 with an excess of Cr(CO)4 · NBD and with extended reaction times. The molecular structures of the compounds were identified by investigating the 31P[1H] NMR spec-tra and considering especially the coordination shift, and by crystal structure determinations of 2 and 4. Compound 2 crystallizes in the space group PI (no.2) with a = 1566.2(4) pm, b = 2304.1(5) pm, c = 1563.3(4) pm,α = 95.57(3)°, β = 108.79(3)°, γ = 109.82(4)° and Z = 4 formula units in the elementary cell. Compound 4 crystallizes in the space group P 21 /n (no. 14) with a = 1416.6(5) pm, b = 2573.6(5) pm, c = 1352.9(4) pm,β = 99.17(5)° and Z = 4 formula units in the elementary cell.  相似文献   

4.
Transition Metal Complexes of P-rich Phosphanes and Silylphosphanes. XI. Formation, Reactions, and Structures of Chromium Carbonyl Complexes from Reactions of Li(THF)22-(tBu2P)2P] with Cr(CO)5 · THF and Cr(CO)4 · NBD Reactions of Li(THF)22-(tBu2P)2P] 1 with Cr(CO)5 · THF yield Li(THF)2Et2O[Cr(CO)42-(tBu2P)2P}η1-Cr(CO)5] 2 and the compounds [Cr(CO)42-(tBu2P)2PH}] 3 , [Cr(CO)51-(tBu2P)2PH}] 4 , (tBu2P)2PH 5 and tBu2PH · Cr(CO)5 6 . The formation of 3, 4, 5 and 6 is due to byproducts coming from the synthesis of 1. 2 reacts with CH3COOH under formation of 3 . After addition of 12-crown-4 1 with NBD · Cr(CO)4 in THF forms Li(12-crown-4)2[Cr(CO)4-{η2-(tBu2P)2P}] 7 (yellow crystals). 7 reacts with CH3COOH to 3 – which regenerates 7 with LiBu – with Cr(CO)5THF to compound 2 , with NBD · Cr(CO)4 in THF to 2 and 3 (ratio 1 : 1). With EtBr, 7 forms [Cr(CO)42-(tBu2P)2PEt}] 8 , and [Cr(CO)42-(tBu2P)2PBr}] 9 with BrCH2? CH2Br. The compounds were characterized by means of 1H, 13C, 31P, 7Li NMR spectroscopy, IR spectroscopy, elementary analysis, mass spectra, and 2, 3 and 4 additionally by means of X-ray diffraction analysis. 2 crystallizes in the space group P1 with 2 formula units in the elementary cell; a = 10.137(9), b = 15.295(12), c = 15.897(14) Å; α = 101.82(7), β = 91.65(7), γ = 98.99(7)°; 3 crystallizes in the space group P2t/n with 4 molecules in the elementary unit; a = 11.914(6), b = 15.217(10), c = 14.534(10) Å; α = 90, β = 103.56(5), γ = 90°. 4 : space group P1 with 2 molecules in the elementary unit; a = 8.844(4), b = 12.291(6), c = 14.411(7) Å, α = 66.55(2), β = 89.27(2), γ = 71.44(2)°.  相似文献   

5.
Transition Metal Complexes of P-rich Phosphanes and Silylphosphanes. VII. Formation and Structure of [Li(DME)3]2{(SiMe3)[Cr(CO)5]2 P-P ? P-P[Cr(CO)5]2(SiMe3)} Deep red crystals of the title compound 1 are produced in the reaction of LiP(Me3Si)2[Cr(CO)5] with 1, 2-dibromoethane in DME. The structure of 1 was derived from the investigation of the 31P-NMR spectra and confirmed by a single crystal structure determination. 1 crystallizes in the space group P1 (no. 2); a = 1307.8(5)pm, b = 1373.1(5)pm, c = 1236.1(4)pm, α = 106.22(4)°, β = 88.00(3)°, γ = 115.52(4)° and Z = 1. 1 forms a salt composed of a dianion R2R4′P42? (R ? SiMe3, R′ ? Cr(CO)5) and solvated Li+ cations. The zigzag shaped dianion possesses the symmetry 1 -Ci. The distances d(P? P) = 202.5(1)pm and d(P? P) = 221.9(1)pm correspond to a double bond and single bonds, respectively. The distances d(Cr? P) = 251.1(1) pm and 255.3(1) pm are larger than those observed so far which might be caused by the charge distribution in the dianion.  相似文献   

6.
Coordination Chemistry of P-rich Phosphanes and Silylphasphanes. XIV. The Phosphinophosphinidene tBu2P? P as a Ligand in the Pt Complexes [η2-{tBu2P? P}Pt(PPh3)2] and [η2-{tBu2P? P}Pt(PEtPh2)2] [η2-{tBu2P? P}Pt(PPh3)2 1 and [η2-{tBu2P? P}Pt(PEtPh2)2] 2 are the first complex compounds of tBu2P? P 5 . They are formed in the reaction of tBu2P? P ? P(Me)tBu2 3 with [η2-{H2C ? CH2}Pt(PPh3)2] 6 or [η2-{H2C ? CH2}Pt(PEtPh2)2] 7 , respectively. Compound 1 is less stable than 2 and reacts on to [η2-{tBu2P? P} Pt(PPh3)(PtBu2Me)] 10 with the coincidently formed tBu2PMe. The molecular structures of 1 and 2 were derived from their 1H and 31P-NMR spectra, 2 was additionally characterized by a X ray structure determination. 2 crystallizes in the monoclinic space group P21/n with a = 1222.36(7) pm, b = 1770.7(1) pm, c = 1729.7(1) pm, β = 108.653(6)°.  相似文献   

7.
Coordination Chemistry of P-rich Phosphanes and Silylphosphanes. XIII [1]. [η2-{tBu2P? P?PtBu2} PtBr(PPh3)] [η2-{tBu2P? P?PtBu2} PtBr(PPh3)] 1 is the first transition metal complex compound resulting from a phosphino-phosphinidene-phosphorane. The yellow crystals of 1 (fp. 201–203°C, decomp.) were obtained by reacting tBu2P? P?P(Br)tBu2 with either (Ph3P)2Pt · C2H4, or with Pt(PPh3)4, resp. Compound 1 crystallizes triclinic in the space group P1 (no. 2) with a = 1076.80(8) pm, b = 1344.61(8) pm, c = 1381.16(9) pm, α = 81.773(6)°, β; = 85,110(8), γ = 88,776(7).  相似文献   

8.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XIX. [Co4P2(PtBu2)2(CO)8] and [{Co(CO)3}2P4tBu4] from Co2(CO)8 and tBu2P–P=P(Me)tBu2 Co2(CO)8 reacts with tBu2P–P=P(Me)tBu2 yielding the compounds [Co4P2(PtBu2)2(CO)8] ( 1 ) and [{η2tBu2P=P–P=PtBu2}{Co(CO)3}2] ( 2 a ) cis, ( 2 b ) trans. In 1 , four Co and two P atoms form a tetragonal bipyramid, in which two adjacent Co atoms are μ2‐bridged by tBu2P groups. Additionally, two CO groups are linked to each Co atom. In 2 a and 2 b , each of the Co(CO)3 units is η2‐coordinated to the terminal P2 units resulting in the cis‐ and trans‐configurations 2 a and 2 b . 1 crystallizes in the orthorhombic space group Pnnm (No. 58) with a = 879,41(5), b = 1199,11(8), c = 1773,65(11) pm. 2 a crystallizes in the monoclinic space group P21/n (No. 14) with a = 875,97(5), b = 1625,36(11), c = 2117,86(12) pm, β = 91,714(7)°. 2 b crystallizes in the triclinic space group P 1 (No. 2) with a = 812,00(10), b = 843,40(10), c = 1179,3(2) pm, α = 100,92(2)°, β = 102,31(2)°, γ = 102,25(2)°.  相似文献   

9.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXV. Formation and Structure of [{ cyclo ‐P3(PtBu2)3}{Ni(CO)2}{Ni(CO)3}] tBu2P–P=P(R)tBu2 (R = Br, Me) reacts with [Ni(CO)4] yielding [{cyclo‐P3(PtBu2)3}{Ni(CO)2}{Ni(CO)3}]. The two cistBu2P substituents of the cyclotriphosphane, which results from the trimerization of the phosphinophosphinidene tBu2P–P, are coordinating to a Ni(CO)2 unit forming a five‐membered P4Ni chelate ring. The transtBu2P group is linked to a Ni(CO)3 unit. The compound crystallizes in the orthorhombic space group Pbca (No. 61) with a = 933.30(5), b = 2353.2(1) and c = 3474.7(3) pm.  相似文献   

10.
Coordination Chemistry of P-rich Phosphanes and Silylphosphanes. XV. Influence of the Chelate Compounds dppe and dppp on Formation and Properties of the Pt Complexes of tBu2P–P The chelating ligands dppe and dppp replace the PPh3 groups in [η2-{tBu2P–P}Pt(PPh3)2] 1 yielding [η2-{tBu2P–P}Pt(dppe)] 2 and [η2-{tBu2P–P}Pt(dppp)] 8 . However, they don't replace the phosphinophosphinidene ligand tBu2P–P. dppm does not react at all with 1 . [η2-{H2C=CH2}Pt(dppe)] 3 yields in the presence of tBu2P–P=P(Me)tBu2 4 exclusively Pt(dppe)2 5 and elemental Pt; no 2 could be detected. Similarly, [η2-{H2C=CH2}Pt(dppp)] 7 reacts with 4 to give mainly Pt(dppp)2 9 and Pt; [η2-{tBu2PP}Pt(PPh3)2] 8 is present only as a minor product. [η2-{tBu2P–P}Pt(dppe)] 2 crystallizes in the monoclinic space group P21/c (no. 14) with a = 1834.40(10) pm, b = 1679.70(10) pm, c = 1125.79(6) pm, β = 103.963(5)°.  相似文献   

11.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes XXI The Influence of the PR3 Ligands on Formation and Properties of the Phosphinophosphinidene Complexes [{η2tBu2P–P}Pt(PR3)2] and [{η2tBu2P1–P2}Pt(P3R3)(P4R′3)] (R3P)2PtCl2 and C2H4 yield the compounds [{η2‐C2H4}Pt(PR3)2] (PR3 = PMe3, PEt3, PPhEt2, PPh2Et, PPh2Me, PPh2iPr, PPh2tBu and P(p‐Tol)3); which react with tBu2P–P=PMetBu2 to give the phosphinophosphinidene complexes [{η2tBu2P–P}Pt(PMe3)2], [{η2tBu2P–P}Pt(PEt3)2], [{η2tBu2P–P}Pt(PPhEt2)2], [{η2tBu2P–P}Pt(PPh2Et)2], [{η2tBu2P–P}Pt(PPh2Me)2], [{η2tBu2P–P}Pt(PPh2iPr], [{η2tBu2P–P}Pt(PPh2tBu)2] and [{η2tBu2P–P}Pt(P(p‐Tol)3)2]. [{η2tBu2P–P}Pt(PPh3)2] reacts with PMe3 and PEt3 as well as with tBu2PMe, PiPr3 and P(c‐Hex)3 by substituting one PPh3 ligand to give [{η2tBu2P1–P2}Pt(P3Me3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3Ph3)(P4Me3)], [{η2tBu2P1–P2}Pt(P3Et3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3MetBu2)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3iPr3)(P4Ph3)] and [{η2tBu2P1–P2}Pt(P3(c‐Hex)3)(P4Ph3)]. With tBu2PMe, [{η2tBu2P–P}Pt(P(p‐Tol)3)2] forms [{η2tBu2P1–P2}Pt(P3MetBu2)(P4(p‐Tol)3)]. The NMR data of the compounds are given and discussed with respect to the influence of the PR3 ligands.  相似文献   

12.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXII. The Formation of [η2‐{tBu–P=P–SiMe3}Pt(PR3)2] from (Me3Si)tBuP–P=P(Me)tBu2 and [η2‐{C2H4}Pt(PR3)2] (Me3Si)tBuP–P = P(Me)tBu2 reacts with [η2‐{C2H4}Pt(PR3)2] yielding [η2‐{tBu–P=P–SiMe3}Pt(PR3)2]. However, there is no indication for an isomer which would be the analogue to the well known [η2‐{tBu2P–P}Pt(PPh3)2]. The syntheses and NMR data of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] and [η2‐{tBu–P=P–SiMe3}Pt(PMe3)2] as well as the results of the single crystal structure determination of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] are reported.  相似文献   

13.
tBu2P‐P=P(Me)tBu2 reacts with [Fe2(CO)9] to give [μ‐(1, 2, 3:4‐η‐tBu2P1‐P2‐P3‐P4tBu2){Fe(CO)3}{Fe(CO)4}] ( 1 ) and [trans‐(tBu2MeP)2Fe(CO)3]( 2 ). With [(η2‐C8H14)2Fe(CO)3] in addition to [μ‐(1, 2, 3:4‐η‐tBu2P1‐P2‐P3‐P4tBu2){Fe(CO)2PMetBu2}‐{Fe(CO)4}] ( 10 ) and 2 also [(μ‐PtBu2){μ‐P‐Fe(CO)3‐PMetBu2}‐{Fe(CO)3}2(Fe‐Fe)]( 9 ) is formed. 1 crystallizes in the monoclinic space group P21/c with a = 875.0(2), b = 1073.2(2), c = 3162.6(6) pm and β = 94.64(3)?. 2 crystallizes in the monoclinic space group P21/c with a = 1643.4(7), b = 1240.29(6), c = 2667.0(5) pm and β = 97.42(2)?. 9 crystallizes in the monoclinic space group P21/n with a = 1407.5(5), b = 1649.7(5), c = 1557.9(16) pm and β = 112.87(2)?.  相似文献   

14.
Metal Derivatives of Molecular Compounds. IV Synthesis, Structure, and Reactivity of Lithium [Tris(trimethylsilyl)silyl]tellanide · DME Lithium tris(trimethylsilyl)silanide · 1,5 DME [3] and tellurium react in 1,2-dimethoxyethane to give colourless lithium [tris(trimethylsilyl)silyl]tellanide · DME ( 1 ). An X-ray structure determination {-150 · 3·C; P21/c; a = 1346.6(4); b = 1497.0(4); c = 1274.5(3) pm; β = 99.22(2)·; Z = 2 dimers; R = 0.030} shows the compound to be dimeric forming a planar Li? Te? Li? Te ring with two tris(trimethylsilyl)silyl substituents in a trans position. Three-coordinate tellurium is bound to the central silicon of the tris(trimethylsilyl)silyl group and to two lithium atoms; the two remaining sites of each four-coordinate lithium are occupied by the chelate ligand DME {Li? Te 278 and 284; Si? Te 250; Li? O 200 pm (2X); Te? Li? Te 105°; Li? Te? Li 75°; O? Li? O 84°}. The covalent radius of 154 pm as determined for the DME-complexed lithium in tellanide 1 is within the range of 155 ± 3 pm, also characteristic for similar compounds. In typical reactions of the tellanide 1 [tris(trimethylsilyl)silyl]tellane ( 2 ), methyl-[tris(trimethylsilyl)silyl]tellane ( 4 ) and bis[tris(trimethylsilyl)silyl]ditellane ( 5 ) are formed.  相似文献   

15.
[t-Bu2P]3P7 and (t-Bu2Sb)3P7, as well as Investigations on the Formation of Heptaphosphanes (3) Containing PMe2, PF2, and P(CF3)2 Groups Tris(di-tert-butylphospha)heptaphosphanortricyclane (t-Bu2P)3P7 1 obtained by reacting Li3P7 · 3 DME with t-Bu2PF forms yellow crystals. (t-Bu2Sb)3P7 2 produced similarly from t-Bu2SbCl and Li3P7 · 3 DME didn't form crystals; it decomposes in a solution of toluene above ?10°C. Both compounds were identified by their 31P{1H} NMR spectra, and 1 also by elemental analysis and single crystal structure determination (space group) P21/a, a = 1 712.0(9) pm, b = 1 105.1(7) pm, c = 1 854.0(10) pm, β = 94.96(4)°, Z = 4 formula units in the elementary cell). Attempts to synthesize (Me2P)3P7 3 , (F2P)3P7 4 and [(F3C)2P]3P7 5 failed as dialkylchlorophosphanes as Me2PCl e. g. with Li3P7 · 3 DME react under Li/Cl exchange, dialkylfluorophosphanes (except t-Bu2PF) disproportionate, and neither PF3 nor (F3C)2PBr with Li3P7 · 3 DME give the desired products 4 or 5 , resp.  相似文献   

16.
Contributions to the Chemistry of Phosphorus. 240. On the Reactive Behaviour of Diphosphane-borane, P2H4 · BH3 Under mild temperature conditions, the thermal decomposition of diphosphane-borane ( 1 ) gives rise to the formation of phosphane-borane, PH3 · BH3, and triphosphane-2-borane, PH2? PH(BH3)? PH2 ( 2 ). In the presence of diphosphane-1,2-bis(borane), triphosphane-1,3-bis(borane), BH3? PH2? PH? PH2? BH3 ( 3 ), is formed additionally. The thermolysis product at room temperature is a polymeric solid of varying composition which contains phosphorus, boron, and hydrogen. Compound 1 reacts with metalating agents such as n-BuLi, LiBH4, and NaBH4 to furnish the borane-trihydrogendiphosphide ion, [PH2? PH? BH3]?, which immediately disproportionates to give the corresponding mono-and triphosphane derivatives. In the presence of an excess of THF-borane and in the case of a 1 : 1 molar ratio of 1 : NaBH4, the disproportionation does not occur and the new diphosphide derivative sodium-1,1,2-tris(borane)-1,2,2-trihydrogendiphosphide, Na[(BH3)2PH? PH2BH3] ( 4 ) can be obtained. The action of additional NaBH4 yields the diphosphide dianion with four coordinated BH3 groups.  相似文献   

17.
Influence of the Ring Atoms on the Structure of Triel‐Pentel Heterocycles – Synthesis and X‐Ray Crystal Structures of [Me2InAs(SiMe3)2]2 and [Me2InSb(SiMe3)2]3 Triel‐pentel heterocycles [Me2InE(SiMe3)2]x have been prepared by dehalosilylation reactions from Me2InCl and E(SiMe3)3 (E = As, x = 2; E = Sb, x = 3) and characterised by NMR spectroscopy and by X‐ray crystal structure analyses. In addition the X‐ray crystal structures of [Me2GaAs(SiMe3)2]2 and [Me2InP(SiMe3)2]2 are reported. The compounds complete a family of 13 identically substituted heterocycles [Me2ME(SiMe3)2]x (M = Al, Ga, In; E = N, P, As, Sb, Bi; x = 2, 3), whose structures were investigated depending on the ring atoms M and E. The tendencies that have been observed concerning the ring sizes can be explained by the interplay of the atomic radii of the central atoms and the sterical demand of the ligands. After a formal separation of the M–E bonds in σ bonds and dative bonds the characteristic differences and trends in the endocyclic and exocyclic bond angles of both centres M and E can be interpreted on the basis of a simple Lewis acid/base adduct model.  相似文献   

18.
[iPr2P]2P? SiMe3 and [iPr2P]2PLi – Synthesis and Reactions Structure of [iPr2P]2P? P[PiPr2]2 [iPr2P]2P? SiMe3 1 and [iPr2P]2PLi 2 were prepared to investigate the influence of the bulky alkyl groups on formation and properties of the ylides R2P? P?P(X)R2 (R = iPr, tBu; X = Br, Me) in reactions of 1 with CBr4 and of 2 with 1,2-dibromoethane or MeCl, resp. Compared to the iPr groups the tBu groups favour the formation of ylides. With CBr4 1 forms iPr2P? P?P(Br)iPr2 5 just as a minor product which decomposes already below ?30°C. With 1,2-dibromoethane 2 yields only traces of 5 but [iPr2P]P? P[P(iPr)2]2 7 as main product. With MeCl 2 gives iPrP? P?P(Me)iPr2 9 and [iPr2P]2PMe 10 in a molar ratio of 1:1. 9 is considerably more stable than 5. 7 crystallizes triclinic in the space group P1 (No. 2) with a = 10.813 Å, b = 11.967 Å, c = 15.362 Å, α = 67.90°, β = 71.36°, γ = 64.11° and two formula units in the unit cell.  相似文献   

19.
The title compounds 3‐5 are accessible by treatment of P(C6H4CH2NMe2)3( 1 ) with CuX ( 2a : X = Cl, 2b : X = Br, 2c : X = I) in the ratio of 1:1 or 1:2 in very good yields. Reaction of 1 with equimolar amounts of 2a affords the copper(I) chloride [P(C6H4CH2NMe2)3]CuCl ( 3 ). With a further equivalent of 2a homobimetallic [P(C6H4CH2NMe2)3]Cu2Cl2 ( 4 ) is formed, which also can be synthesized by the reaction of 1 with two equivalents of 2a. Complex 3 reacts with CuX (X = Br, I)to afford [P(C6H4CH2NMe2)3]Cu2ClX ( 5a : X = Br; 5b : X = I) in which mixed halides are present. The newly synthesized complexes 3‐5 were characterized by elemental analyses, by their IR‐, 1H‐, 13C{1H}‐ and 31P{1H}‐NMR spectra as well as by mass spectrometrical studies. The solid‐state structures of complexes 3 and 4 are reported. Mononuclear 3 crystallizes in the monoclinic space group P21/c with the cell parameters a = 14.285(2), b = 10.853(2), c = 17.425(2) Å , β = 103.310(10)?, V = 2628.9(7) Å 3 and Z = 4 with 4053 observed unique reflections; R1 = 0.0314. The crystal structure of 3 consists of monomeric molecules with planar coordinated copper(I) centres (CuClNP). Homobimetallic 4 crystallizes in the monoclinic space group P21/n with a = 23.905(4), b = 10.874(3), c = 25.314(5), β = 99.130(10)?, V = 6497(2) /Aring; 3 and Z = 4 with 9021 observed unique reflections; R1 = 0.0480. In 4 one of two copper(I) centres possesses a distorted trigonal‐pyramidal environment, while the other one is almost square‐pyramidal coordinated. The Cu2Cl2 segment resembles to a building block which is set up by a contact ion pair consisting of Cu+ and [CuCl2] , respectively.  相似文献   

20.
[(tBu)2P]2P? P[P(tBu)2]2 from LiP[P(tBu)2]2 and 1,2-Dibromomethane. Pyrolysis of tBu2P? P?P(Br)tBu2 All products of the reaction of [tBu2P]2PLi 1 with 1,2-dibromoethane 2 were investigated. Already at ?70°C tBu2P? P?P(Br)tBu2 3 as main product and [tBu2P]2PBr 4 are formed. Only with an excess of 1 also [tBu2P]P? P[P(tBu)2]2 5 is obtained. Warming of a pure solution of 3 in toluene from ?70°C to ?30°C leads to 4 , and at 20°C tBu2PBr and the cyclophosphanes P4[P(tBu)2]4 and P3[P(tBu)2]3 are observed. 5 does not result from 3 , it's rather a byproduct from the reaction of 1 with 4 . Also the ylide 3 and 1 yields 5 .  相似文献   

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