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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 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 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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(SO4)-rich silicate analogue borosulfates are able to stabilise cationic cluster-like and chain-like aggregates. Single crystals of [Au3Cl4][B(S2O7)2] and [Au2Cl4][B(S2O7)2](SO3) were obtained by solvothermal reaction with SO3, and the electronic properties were investigated by means of density functional theory–based calculations. [Au3Cl4][B(S2O7)2] exhibits a cluster-like cation, and the cationic gold-chloride strands in [Au2Cl4][B(S2O7)2](SO3) are found to resemble one-dimensional metallic wires. This is confirmed by polarisation microscopy.  相似文献   

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Novel Gold Selenium Complexes: Syntheses and Structures of [Au10Se4(dpppe)4]Br2, [Au2Se(dppbe)], [(Au3Se)2(dppbp)3]Cl2, and [Au34Se14(tpep)6(tpepSe)2]Cl6 The reaction of gold phosphine complexes [(AuX)(PR3)] (X= halogen; R = org. group) with Se(SiMe3)2 yield to new chalcogeno bridged gold complexes. Especially within the use of polydentate phosphine ligands cluster complexes like [Au10Se4(dpppe)4]Br2 ( 1 ) (dpppe = 1, 5‐Bis(diphenylphosphino)pentane), [Au2Se(dppbe)] ( 2 ) (1, 4‐Bis(diphenylphosphino)benzene), [(Au3Se)2(dppbp)3]Cl2 ( 3 ) (dppbp = 4, 4′‐Bis‐diphenylphosphino)biphenyl) und [Au34Se14(tpep)6(tpepSe)2]Cl6 ( 4 ) (tpep = 1, 1, 1‐Tris(diphenylphosphinoethyl)phosphine, tpepSe = 1, 1‐Bis(diphenylphosphinoethyl)‐1‐(diphenylselenophosphinoethylphosphine) could be isolated and their structures could be determined by X‐ray diffraction. ( 1: Space group P1 (No. 2), Z = 2, a = 1642.1(11), b = 1713.0(9), c = 2554.0(16) pm, α = 80.41(3)°, β = 76.80(4)°, γ = 80.92(4)°; 2: Space group P21/n (No. 14), Z = 4, a = 947.3(2), b = 1494.9(3), c = 2179.6(7) pm, β = 99.99(3)°; 3: Space group P21/c (No. 14), Z = 8, a = 2939.9(6), b = 3068.4(6), c = 3114.5(6) pm, β = 109.64(3)°; 4: Space group P1 (No. 2), Z = 1, a = 2013.7(4), b = 2420.6(5), c = 2462.5(5) pm, α = 77.20(3), β = 74.92(3), γ = 87.80(3)°).  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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A simple synthesis of 2‐hydrazinylidene‐3‐hydroxy‐4H‐furo[3,2‐c]pyran‐4‐ones is described. A mixture of (isocyanoimino)(triphenyl)phosphorane, an aromatic aldehyde, and dehydroacetic acid (=3‐acetyl‐2‐hydroxy‐6‐methyl‐4H‐pyran‐4‐one) undergo a 1 : 1 : 1 addition reaction under mild conditions to afford the title compounds in excellent yields.  相似文献   

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Synthesis and Spectroscopic Characterization of [Rh(SeCN)6]3– and trans ‐[Rh(CN)2(SeCN)4]3–, Crystal Structure of (Me4N)3[Rh(SeCN)6] Treatment of RhCl3 with KSeCN in acetone yields a mixture of selenocyanato‐rhodates(III), from which [Rh(SeCN)6]3– and trans‐[Rh(CN)2(SeCN)4]3– have been isolated by ion exchange chromatography on diethylaminoethyl cellulose. The X‐ray structure determination on a single crystal of (Me4N)3[Rh(SeCN)6] (trigonal, space group R3, a = 14.997(2), c = 24.437(3) Å, Z = 6) reveals, that the compound crystallizes isotypically to (Me4N)3[Ir(SCN)6]. The exclusively via Se coordinated selenocyanato ligands are bonded with the average Rh–Se distance of 2.490 Å and the Rh–Se–C angle of 104.6°. In the low temperature IR and Raman spectra the metal ligand stretching modes ν(RhSe) of (n‐Bu4N)3[Rh(SeCN)6] ( 1 ) and trans‐(n‐Bu4N)3[Rh(CN)2(SeCN)4] ( 2 ) are in the range of 170–250 cm–1. In 2 νas(CRhC) is observed at 479 cm–1. The vibrational spectra are assigned by normal coordinate analysis based on the molecular parameters of the X‐ray determination. The valence force constants are fd(RhSe) = 1.08 ( 1 ), 1.10 ( 2 ) and fd(RhC) = 3.14 mdyn/Å ( 2 ). fd(RhS) = 1.32 mdyn/Å is determined for [Rh(SCN)6]3–, which has not been calculated so far. The 103Rh NMR resonances are 2287 ( 1 ), 1680 ppm ( 2 ) and the 77Se NMR resonances are –32.7 ( 1 ) and –110.7 ppm ( 2 ). The Rh–C bonding of the cyano ligand in 2 is confirmed by a dublett in the 13C NMR spectrum at 136.3 ppm.  相似文献   

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