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1.
Upon reacting P(4)S(3) with AgAl(hfip)(4) and AgAl(pftb)(4) [hfip = OC(H)(CF(3))(2); pftb = OC(CF(3))(3)], the compounds Ag(P(4)S(3))Al(hfip)(4) 1 and Ag(P(4)S(3))(2)(+)[Al(pftb)(4)](-) 2 formed in CS(2) (1) or CS(2)/CH(2)Cl(2) (2) solution. Compounds 1 and 2 were characterized by single-crystal X-ray structure determinations, Raman and solution NMR spectroscopy, and elemental analyses. One-dimensional chains of [Ag(P(4)S(3))(x)](infinity) (x = 1, 1; x = 2, 2) formed in the solid state with P(4)S(3) ligands that bridge through a 1,3-P,S, a 2,4-P,S, or a 3,4-P,P eta(1) coordination to the silver ions. Compound 2 with the least basic anion contains the first homoleptic metal(P(4)S(3)) complex. Compounds 1 and 2 also include the long sought sulfur coordination of P(4)S(3). Raman spectra of 1 and 2 were assigned on the basis of DFT calculations of related species. The influence of the silver coordination on the geometry of the P(4)S(3) cage is discussed, additionally aided by DFT calculations. Consequences for the frequently observed degradation of the cage are suggested. An experimental silver ion affinity scale based on the solid-state structures of several weak Lewis acid base adducts of type (L)AgAl(hfip)(4) is given. The affinity of the ligand L to the silver ion increases according to P(4) < CH(2)Cl(2) < P(4)S(3) < S(8) < 1,2-C(2)H(4)Cl(2) < toluene.  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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Synthesis, Vibrational Spectra, and Crystal Structures of the Nitrato Argentates (Ph4P)[Ag(NO3)2(CH3CN)]·CH3CN and (Ph4P)[Ag2(NO3)3] Tetraphenylphosphonium bromide reacts in acetonitril suspension with excess silver nitrate to give (Ph4P)[Ag(NO3)2(CH3CN)]·CH3CN ( 1 ), whereas (Ph4P)[Ag2(NO3)3] ( 2 ) is obtained in a long‐time reaction from (Ph4P)Br and excess AgNO3 in dichloromethane suspension. Both complexes were characterized by vibrational spectroscopy (IR, Raman) and by single crystal structure determinations. 1 : Space group P21/c, Z = 4, lattice dimensions at 193 K: a = 1781.5(3), b = 724.8(1), c = 2224.2(3) pm, β = 96.83(1)°, R1 = 0.0348. 1 contains isolated complex units [Ag(NO3)2(CH3CN)]?, in which the silver atom is coordinated by the chelating nitrate groups and by the nitrogen atom of the solvated CH3CN molecule with a short Ag—N distance of 220.7(4) pm. 2 : Space group I2, Z = 4, lattice dimensions at 193 K: a = 1753.4(4), b = 701.7(1), c = 2105.5(4) pm, R1 = 0.072. In the polymeric anions [Ag2(NO3)3]? each silver atom is coordinated in a chelating manner by one nitrate group and by two oxygen atoms of two bridging nitrate ions. In addition, each silver atom forms a weak π‐bonding contact with a phenyl group of the (Ph4P)+ ions with shortest Ag···C separations of 266 and 299 pm, respectively, indicating a (4+1) coordination of silver atoms.  相似文献   

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The reactions of P4S3 with As4S3 and of P4Se3 with As4Se3 in the molten state yields molecules of the type P m As4–m S3 and P m As4–m Se3, respectively. A method was developed to separate the different components by the HPLC technique, and to determine their concentrations. The identification of the isomers in the HPLC pattern was achieved with the aid of the LC-MS method. In the selenium system, the distribution of the different species is statistical. In the system P4S3-As4S3, the formation of PAs3S3 with one phosphorus atom in the apical position is favoured.
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农业害虫药材甲Stegobium panicem Linnae在我国各省区都有分布,主要危害谷类、食品、药材、图书、档案等.我国一般每年可以发2~3代,温度较高的地区可发生4代[1] .  相似文献   

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Résumé Nous avons montré par spectrométrie Raman à chaud et mesure des tensions de vapeur que P4S3 se vaporise de façon congruente tandis que P4S7 et P4S10 se dissocient dès le début de leur vaporisation. P4S7 donne réversiblement P4S3 et soufre. P4S10 se dissocie irréversiblement en P4S7 et soufre. A l'état de vapeur non saturante, P4S3 se dissocie au-dessus de 600° avec formation de phosphore, de soufre et d'autres espèces non identifiées.Nous avons mesuré expérimentalement la capacité calorifique de P4S3 liquide, calculé celle de P4S3 gazeux et son entropie standard. Nous avons aussi estimé l'enthalpie standard de vaporisation de P4S3 à l'aide des mesures des tensions de vapeur saturante. Nous en avons déduit l'entropie standard de P4S3 liquide et son point d'ébullition.
It is shown by Raman spectroscopy at high temperature and by vapor tensimetric measurements that the vaporisation of P4S3 is congruent, whereas P4S7 and P4S10 dissociate at the beginning of vaporisation. P4S7 gives P4S3 and sulfur reversibly. The dissociation of P4S10 into P4S7 and sulfur is irreversible. Above 600°, in non-saturated vapour the dissociation of P4S3 gives phosphorus, sulfur and some unidentified gaseous species. The heat capacity of liquid P4S3 has been measured. That of gaseous P4S3 and its standard entropy have been calculated. The vaporisation standard enthalpy of P4S3 has been estimated from the experimental results on the saturated vapour pressures. The standard entropy of liquid P4S3 and its boiling point have been derived from these data.

Zusammenfassung Mittels Raman-Spektrometrie bei erhöhter Temperatur und durch Messung der Dampfdrucke wurde festgestellt, daß sich P4S3 verflüchtigt, während P4S7 und P4S10 mit Beginn der Verflüchtigung dissoziieren. P4S7 ergibt reversibel P4S3 und Schwefel. Im Zustand ungesättigten Dampfes dissoziiert P4S3 oberhalb von 600° unter Bildung von Phosphor, Schwefel und anderer nicht identifizierter Substanzen.Die Wärmekapazität von flüssigem P4S3 wurde gemessen, während die vom gasförmigem P4S3 sowie seine Standard-Entropie berechnet wurden. Die Standard-Enthalpie der Verflüchtigung des P4S3 wurde durch Messungen der Sättigungs-Dampfdrucke ermittelt. Daraus wurden die Standard-Entropie des flüssigen P4S3 sowie sein Siedepunkt berechnet.

- - , P4S3 , P4S7 P4S10 . P4S7 P4S3 , P4S10 P4S7 . 600° P4S3 , . P4S3, P4S3 . P4S3. P4S3 .


Nous remercions Monsieur Letoffe du laboratoire du Professeur J. Bousquet, INSA de Lyon, 20 Avenue Albert Einstein 401, 69621 Villeurbanne, qui a r6alis6 pour nous les déterminations expérimentales des capacités calorifiques de P4S8 liquide.  相似文献   

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价廉易得的L-亮氨酸先以苄基同时保护氨基及羧基得(S)-2-(二苄胺基)-4-甲基戊酸苄酯,进而在碱性条件下与乙腈发生亲核取代反应得(S)-4-(二苄胺基)-6-甲基-3-氧代庚腈,再经硼氢化钠选择性还原羰基得(3S,4S)-4-(二苄胺基)-3-羟基-6-甲基庚腈,用双氧水氧化得(3S,4S)-4-(二苄胺基)-3-羟基-6-甲基庚酸,最后在Pd(OH)2/C-H2作用下脱掉苄基得到(3S,4S)-4-氨基-3-羟基-6-甲基庚酸,即(3S,4S)-statine。整个合成路线总产率为33.6%。  相似文献   

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New Phosphido-bridged Multinuclear Complexes of Ag, Cd and Zn. The Crystal Structures of [Ag4(PPh2)4(PMe3)4], [Ag6(PPh2)6(PtBu3)2] and [M4Cl4(PPh2)4(PnPr3)2] (M = Zn, Cd) AgCl reacts with Ph2PSiMe3 in the presence of a tertiary Phosphine PMe3 or PtBu3 to form the multinuclear complexes [Ag4(PPh2)4(PMe3)4] ( 1 ) and [Ag6(PPh2)6(PtBu3)2] ( 2 ). In analogy to that MCl2 reacts with Ph2PSiMe3 in the presence of PnPr3 to form the two multinuclear complexes [M4Cl4(PPh2)4(PnPr3)2] (M = Zn ( 3 ), Cd ( 4 )). The structures were characterized by X-ray single crystal structure analysis ( 1 : space group Pna21 (Nr. 33), Z = 4, a = 1 313.8(11) pm, b = 1 511.1(6) pm, c = 4 126.0(18) pm, 2 : space group P1 (Nr. 2), Z = 2, a = 1 559.0(4) pm, b = 1 885.9(7) pm, c = 2 112.4(8) pm, α = 104.93(3)°, β = 94.48(3)°, γ = 104.41(3)°; 3 : space group C2/c (Nr. 15), Z = 4, a = 2 228.6(6) pm, b = 1 847.6(6) pm, c = 1 827.3(6) pm, β = 110.86(2); 4 : space group C2/c (Nr. 15), Z = 4, a = 1 894.2(9) pm, b = 1 867.9(7) pm, c = 2 264.8(6) pm, β = 111.77(3)°). 3 and 4 may be considered as intermediates on the route towards polymeric [M(PPh2)2]n (M = Zn, Cd).  相似文献   

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本文用(NH4)2WS4,Ag[S2P(OCH2Ph)2]和PPh3为原料合成了簇合物[WS4Ag3(PPh3)3{S2P(OCH2Ph)3}],并得到了晶体。晶体属正交晶系,空间群为P212121,晶胞参数a=1.32370(4)nm,b=1.34427(4)nm,c=3.83246(11)nm。X-射线单晶结构测定结果表明它具有巢状分子结构,配体(PhCH2O)2PS2-(简称dtp)的两个S原子中的一个硫原子仅与一个金属原子配位,另一个硫原子则同时与两个金属原子配位。簇合物的非线性光学性质用脉宽8ns激光在532nm波长进行了研究。该化合物表现为一定的光学吸收和强的自聚焦效应,其三阶非线性吸收系数α2=1.50×10-10m·W-1,折射系数n2=2.45×10-11esu。  相似文献   

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Investigations Concerning the Metallation of the Cyclotetraphosphanes P4(Cme3)3(Sime3), P4(Cme3)2(Sime3)2, and P4(Sime3)4 The reaction of white phosphorus with LiCme3 and me3SiCl yields P4(Sime3)(Cme3)3 1 . With n-buLi this crystalline cyclotetraphosphane forms the crystalline LiP4(Cme3)3. In the same manner, n-buLi, with trans-P4(Sime3)2(Cme3)2 2 to yields LiP4(Sime3)(Cme3)2, which in contrast to LiP4(Cme3)3 decomposes within a few hours yielding P(Sime3)2n-bu 6 , P(Sime3)3 8 , LiP(Sime3)2 9 and also the cyclic compounds P4(Sime3)(Cme3)3 10 , LiP4(Cme3)3 11 and LiP3(Cme3)2 12 . The composition of the product mixture depends on the molar ratio of 2 to LiC4H9. At a molar ratio of 1:1 11 and 12 are not jet observed. At molar ratios of 1:1.5 and 1:2 P(Sime3)3 is not found. The amount of 11 and 12 grows with increasing concentration of n-buLi. On addition of n-buLi the solution of P4(Sime3)4 immediately turns red. Li3P7 and Li2P7(Sime3) (among others) are formed so fast that the first intermediates in the lithiation sequence so far could not be elucidated. These results demonstrate clearly that replacement of two me3Si groups in P4(Sime3)4 by two me3C groups excludes the rearrangement of LiP4(Sime3)(Cme3)2 to a P7-molecule.  相似文献   

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Stable beta-Ag2S nanocrystals were dispersed in the Ag4Te3O8 glass network. These beta-Ag2S nanocrystals modified the tellurite network by rupturing the Te-O-Te linkages in the tellurite matrix. This structural modification was found to be different from that of the AgI doped silver tellurite glasses. The presence of beta-Ag2S nanoparticles was confirmed from the transmission electron micrographs. The structural modification was observed in the Fourier transform infrared spectra of the composites. Electrical properties for these composites were investigated in the temperature range of 125-303 K and in the frequency range of 10 Hz-2 MHz and were compared with those of the AgI doped silver tellurite glass system to shed some light on the influence of Ag2S nanoparticles on the ionic conduction and relaxation in the silver tellurite nanocomposites. The ionic relaxation in this system was also investigated using the electrical modulus formalism. Formation of nanocrystal in this nanocomposite system left some signature on the frequency exponent, crossover frequency, and the relaxation frequency, which became clear when compared with those of the silver tellurite glasses.  相似文献   

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The reaction of S4N4Cl2 with CH3OH gives S4N4(OCH3)2, a simple dimethoxoderivative of S4N4. Its overall geometry is analogous to other compounds of the S4N4X2 type. The chlorination of S4N4(OCH3)2 leads to the oxidation of one sulfur atom to SVI and CH3OS4N4(O)Cl is formed. The compounds were characterized by ir spectroscopy and their crystal structures were determined from single crystal diffraction data collected at ?153°C. The presence of SVI in the molecule of CH3OS4N4(O)Cl is manifested by a marked shortening of the bonds formed by this atom as compared with S4N4Cl2 and S4N4(OCH3)2.  相似文献   

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