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PX(4) (+)[Al(OR)(4)](-) (X=I: 1 a, X=Br: 1 b) was prepared from X(2), PX(3), and Ag[Al(OR)(4)] [R=C(CF(3))(3)] in CH(2)Cl(2) at -30 degrees C in 69-86 % yield. P(2)X(5) (+) salts were prepared from 2 PX(3) and Ag[Al(OR)(4)] in CH(2)Cl(2) at -30 degrees C yielding almost quantitatively P(2)X(5) (+)[Al(OR)(4)](-) (X=I: 3 a, X=Br: 3 b). The phosphorus-rich P(5)X(2) (+) salts arose from the reaction of cold (-78 degrees C) mixtures of PX(3), P(4), and Ag[Al(OR)(4)] giving P(5)X(2) (+)[Al(OR)(4)](-) (X=I: 4 a, X=Br: 4 b) with a C(2v)-symmetric P(5) cage. Silver salt metathesis presumably generated unstable PX(2) (+) cations from PX(3) and Ag[Al(OR)(4)] (X=Br, I) that acted as electrophilic carbene analogues and inserted into the Xbond;X (Pbond;X/Pbond;P) bond of X(2) (PX(3)/P(4)) leading to the highly electrophilic and CH(2)Cl(2)-soluble PX(4) (+) (P(2)X(5) (+)/P(5)X(2) (+)) salts. Reactions that aimed to synthesize P(2)I(3) (+) from P(2)I(4) and Ag[Al(OR)(4)] instead led to anion decomposition and the formation of P(2)I(5)(CS(2))(+)[(RO)(3)Al-F-Al(OR)(3)](-) (5). All salts were characterized by variable-temperature solution NMR studies (3 b also by (31)P MAS NMR), Raman and/or IR spectroscopy as well as X-ray crystallography (with the exception of 4 a). The thermochemical volumes of the Pbond;X cations are 121 (PBr(4) (+)), 161 (PI(4) (+)), 194 (P(2)Br(5) (+)), 271 (P(2)I(5) (+)), and 180 A(3) (P(5)Br(2) (+)). The observed reactions were fully accounted for by thermochemical calculations based on (RI-)MP2/TZVPP ab initio results and COSMO solvation enthalpy calculations (CH(2)Cl(2) solution). The enthalpies of formation of the gaseous Pbond;X cations were derived as +764 (PI(4) (+)), +617 (PBr(4) (+)), +749 (P(2)I(5) (+)), +579 (P(2)Br(5) (+)), +762 (P(5)I(2) (+)), and +705 kJ mol(-1) (P(5)Br(2) (+)). The insertion of the intermediately prepared carbene analogue PX(2) (+) cations into the respective bonds were calculated, at the (RI-)MP2/TZVPP level, to be exergonic at 298 K in CH(2)Cl(2) by Delta(r)G(CH(2)Cl(2))=-133.5 (PI(4) (+)), -183.9 (PBr(4) (+)), -106.5 (P(2)I(5) (+)), -81.5 (P(2)Br(5) (+)), -113.2 (P(5)I(2) (+)), and -114.5 kJ mol(-1) (P(5)Br(2) (+)).  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

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M. LIN  Q. ZHANG 《ChemInform》1991,22(31):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

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Azido Complexes of Vanadium(IV) and Vanadium(V): (Ph4P)2[VOCl2(μ‐N3)]2 and (Ph4P)2[VOCl(μ‐N3)(N3)2]2 (Ph4P)2[VOCl2(μ‐N3)]2 ( 1 ) was prepared by reaction of (Ph4P)[VO2Cl2] with trimethylsilylazide in the molar ratio 1:2 in dichloromethane solution to give dark green, moisture sensitive, non‐explosive single crystals. The reaction is accompanied by the formation of the dark blue side‐product (Ph4P)2[VOCl(μ‐N3)(N3)2]2 ( 2a ), which can be obtained as the main product by application of a large excess of Me3SiN3. Dark blue needles of 2a crystallize spontaneously from the CH2Cl2 solution within one hour at 4 °C. After standing at 4 °C under its mother liquid within 24 hours a first‐order phase transition of 2a occurs forming dark blue prismatic single crystals of 2b . According to single crystal X‐ray structure determinations, 2a and 2b crystallize in the same type of space group , however, with different lattice dimensions. The vanadium(IV) complex 1 is characterized by X‐ray structure determination and by vibrational spectroscopy (IR, Raman) as well as by EPR spectroscopy, whereas 2b is characterized by IR spectroscopy. 1 : Space group P21/n, Z = 2, a = 1009.5(1), b = 1226.6(2), c = 1943.0(2) pm, β = 98.42(1)°, R1 = 0.0672. The complex anion forms centrosymmetric units with V2N2‐four‐membered rings with a V···V distance of 335.6(1) pm and coordination number five on the vanadium(IV) atoms. 2a : Space group , Z = 1, a = 1089.0(2), b = 1097.1(2), c = 1310.1(2) pm, α = 92.99(1)°, β = 106.12(2)°, γ = 117.05(2)°, V = 1309.8(4) Å3, dcalc. = 1.440 g·cm?3, R1 = 0.0384. The complex anion forms centrosymmetric units of symmetry Ci with V2N2 four‐membered rings and VN bond lengths of 200.4(3) and 234.4(2) pm, respectively. The non‐bonding V···V distance amounts to 356.2(1) pm. 2b : Space group , Z = 1, a = 1037.3(2), b = 1157.6(2), c = 1177.2(2) pm, α = 98.48(2)°, ° = 103.82(2)°, γ = 106.33(2)°, V = 1281.8(4) Å3, dcalc. = 1.471 g·cm?3, R1 = 0.0724. The structure of the complex anion is similar to the anion of 2a with VN bond lengths of the four‐membered V2N2 ring of 203.3(4) and 235.2(4) pm, respectively, and a non‐bonding V···V distance of 357.5(1) pm.  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

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杂多化合物的衍生物由于具有潜在的多功能催化性能,长期以来一直受到人们的关注[1~3].将有机或有机金属基团引入杂多化合物中以修饰杂多阴离子的部分外部骨架结构,对研究杂多化合物的性质和应用及新型催化剂的开发具有重要意义[4,5].在杂多化合物表面引入适当的有机基团还可改善其溶解性能及其它物理性质,从而拓宽其应用范围.研究结果表明,这类化合物还具有很好的抗病毒和抗肿瘤活性[6,7].Klemperer等[8]合成的[(η5-C5H5)TiPW11O39]4-将多酸与金属有机化合物有机地融为一体,从而开辟了多酸金属有机化学的新领域.此后,相继合成了许多多酸型金属有机化合物[9],然而缺位杂多阴离子的有机膦衍生物的研究却鲜见报道[10].  相似文献   

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On a New Copper Tin Borate Oxide with Isolated BO3 Units: Cu5Sn(BO3)2O4 Single Crystals of the new compound Cu5Sn(BO3)2O4 were obtained by a B2O3 fluxtechnique. They crystallize in a monoclinic distorted variant of a Ludwigite structure with a partly ordered metal distribution. X-ray investigations on single crystals led to the space group C–P21/c (No. 14); a = 6.3526(7); b = 9.502(1); c = 12.100(9) Å; β = 93.30(3)°; Z = 4. All metal-sites are distorted octahedraly coordinated by oxygen-ions. The structure contains BO3-units and oxygen which is not coordinated to boron.  相似文献   

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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   

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Synthesis and Molecular Structure of the Binuclear tert-Butyliminovanadium(IV) Complexes [(μ-NtC4H9)2V2(CH2CMe3)2X2] (X = OtC4H9, CH2CMe3) Syntheses of the neopentylvanadium(V) compounds tC4H9N?V(CH2CMe3)3?n(OtC4H9)n (n = 0 ( 7 ), 1 ( 6 ), 2) are described. 6 and 7 decompose by irradiation splitting off neopentane and yielding the binuclear diamagnetic neopentylvanadium(IV) complexes [(μ-NtC4H9)2V2(CH2CMe3)2X2] [X = OtC4H9 ( 8 ), CH2CMe3 ( 11 )]. All compounds obtained are characterized by 1H and 51V NMR spectroscopy. 8 has been found by X-ray diffraction analysis to be a binuclear complex with bridging tert-butylimino ligands and a vanadium—vanadium single bond. The complexes tC4H9N?V(CH2C6H5)(OtC4H9)2 and [(μ-NtC4H9)2V2(CH2SiMe3)2(OtC4H9)2] ( 10 ) have been also prepared; the crystal structure of 8 and 10 are nearly identical.  相似文献   

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ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.  相似文献   

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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   

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