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1.
Parent dihydropyrene 1 and 2,7-di-tert-butyldihydropyrene 3 are monoprotonated with FSO3H/SO2CIF to give their persistent monoarenium ions 1H + and 3H + by the attack of proton at C-3 (peri to the ethano-bridge not at C-1 as previously suggested). Dihydropyrene 3 is diprotonated in FSO3H.SbF5 1∶1 “Magic Acid”R/SO2CIF to give the symmetrical dication 3H 2 +2, similar diprotonation of 1 with “Magic Acid”/SO2CIF or with FSO3H.SbF5 (4∶1)/SO2CIF gave the diprotonated species 1H 2 +2 in a mixture. NMR characteristics of the mono- and dications are discussed. On raising temperature or on prolonged cold storage, 1H + and 3H + are converted to their corresponding pyrenium cations (2H + and 4H +). Formation of 2H + from 1 is more rapid than conversion of 3 to 4H +. Parent pyrenium cation was independently generated by protonation with FSO3H/SO2CIF. When a mixture of 2 and 1 is reacted with FSO3H/SO2CIF (dry ice/acetone temperature) only 2H + is seen in the NMR (concomitant presence of the radical cation 1 ++ is inferred from EPR). Similar protonation of a mixture of 6-chlorochrysene 5 and 1 with FSO3H/SO2CIF leads to NMR observation of 1H + (with concomitant presence of 5 ++); on raising temperature 1H + is converted to 2H +. The nature of the paramagnetic radical cation (RC) present in the arenium ion samples influences the position, and resolution of the NMR spectra. This approach may prove useful in NMR studies of large polycyclic aromatic hydrocarbons PAHs where concomitant RC formation greatly diminishes the quality of the NMR spectra.  相似文献   

2.
The reactivity of N1-alkylsulfonyl- and N1-arylsulfonyl-2′,3′,5′-tri-O-acetylinosine with benzylamine and with 15NH3, regarding the attack on C2, has been shown to be in the order CF3SO2 (Tf) > 2,4-(NO2)2C6H3SO2 (DNs) ? 4-NO2C6H4SO2 (pNs) ≈ C6F5SO2 (PFBs) > 2-NO2C6H4SO2 (Ns) ? CH3SO2 (Ms) > 4-CH3C6H4SO2 (Ts) > 2,4,6-(CH3)3C6H2SO2 (Mts). In spite of its intermediate reactivity, the Ns group is the most appropriate, since in this case the formation of by-products is minimised during the ring-opening and ring-closing steps of the process. Another advantage of the Ns group is thus disclosed.  相似文献   

3.
The lanthanide sulphate octahydrates Ln2(SO4)3·8H2O (Ln=Ho, Tm) and the respective tetrahydrate Pr2(SO4)3·4H2O were obtained by evaporation of aqueous reaction mixtures of trivalent rare earth oxides and sulphuric acid at 300 K. Ln2(SO4)3·8H2O (Ln=Ho, Tm) crystallise in space group C2/c (Z=4, aHo=13.4421(4) Å, bHo=6.6745(2) Å, cHo=18.1642(5) Å, βHo=102.006(1) Å3 and aTm=13.4118(14) Å, bTm=6.6402(6) Å, cTm=18.1040(16) Å, βTm=101.980(8) Å3), Pr2(SO4)3·4H2O adopts space group P21/n (a=13.051(3) Å, b=7.2047(14) Å, c=13.316(3) Å, β=92.55(3) Å3). The vibrational and optical spectra of Ho2(SO4)3·8H2O and Pr2(SO4)3·4H2O are also reported.  相似文献   

4.
The complexes C5H5CuPR3 (R = Me, Pri), C5H5AuPR3 (R = Me, Pri), C5Me5CuPR3 (R = Me, Pri, Ph) and C5Me5AuPR3 (R = Pri, Ph) are prepared from [ClCuPR3]n or ClAuPR3 and LiC5H5 (TlC5H5) or LiC5Me5, respectively. According to the 1H and 13C NMR spectra, the cyclopentadienyl and pentamethylcyclopentadienylgold compounds are fluxional in solution. The X-ray crystal structure of C5H5AuPPr3i has been determined at ?120°C. The gold atom is in a linear arrangement (PAuC(1) = 177.0(2)°) and primarily σ-bonded to the cyclopentadienyl ring which shows a weak “slip distortion” toward a η3-mode of coordination. The complexes C5R′5AuPR3 (R′ = H, Me) and C5Me5CuPPr3i react with 1-alkynes such as C2H2, HC2Ph and HC2CO2Me to form alkinylgold and copper compounds R″C2MPR3. They have been characterized by IR, UV and NMR (1H, 13C, 31P) spectroscopy.  相似文献   

5.
Several spectroscopic characteristics of the structure and of the nature of internal bonds in allyl groups C3H+5, C3H·5 and C3H?5 are compared and clearly deduced from infrared and Raman spectra of some organometallic compounds.  相似文献   

6.
The Raman and infrared spectra (4000200 cm?1) of (C4H4P)Mn(CO)3 and (C4D4P)Mn(CO)3, and of [C4H2(CH3)2P]Mn(CO)3 and [C4D2(CH3)2P]Mn(CO)3 in the liquid and solid states (10–400 K) have been investigated. A complete vibrational assignment is proposed and valence force fields of the (C5H5) and (C4H4P) cycles are compared. From these results, it is clearly shown that the (C4H4P) rings are more electrophilic and weaker π-electron donors than (C5H5) rings, this is in agreement with their chemical behavior.  相似文献   

7.
The ionic complex [(π-C5H5)2Zr(H2O)3]2+(CF3SO3?)2·THF, which corresponds to the 18-electron rule, is formed in the reaction of (π-C5H5)2Zr(CF3SO3)2(THF) with H2O in tetrahydrofuran. It crystallizes in the hexagonal space group P63 with Z = 6 and unit cell dimensions at ? 100°C of a 21.945(5) and c 8.711(3) Å. The geometry of the (π-C5H5)2Zr moiety (length of the vectors between Zr and the C5 ring centroids: 2.210 and 2.193 Å; angle between these vectors: 129.0°; angle between the C5 ring normals: 128.3°) agrees with that of neutral, four-coordinate (π-C5H5)2ZrX2 compounds. The three H2O ligands lie in the plane that bisects the angle between the C5 ring planes. The ZrO distances are 2.239(7), 2.195(7), and 2.261(7) Å. The CF3SO3? anions and the THF molecule of crystallization are packed around the complex cation in such a way that their oxygen atoms point towards the H2O ligands. The CF3 sides of the anion, on the other hand, are clustered together so as to produce hydrophobic domains in the crystal structure.  相似文献   

8.
在G3XMP2//B3LYP/6-311+G(3df,2p)水平上对CH3SO3裂解反应的机理进行了研究, 获得了6 条通道(10 条路径), 并构建了其势能剖面. 同时采用单分子反应理论计算了各个通道在温度200-3000 K区间的速率常数. 研究结果表明, 在计算温度范围内, CH3SO3裂解反应的主产物为P1(CH3+SO3), 产物P2(CH3O+SO2)和P3(HCHO+HOSO)仅在温度大于3000 K时对总产物有贡献, 而产物P4(CHSO2+H2O), P5(CH2SO3+H)和P6(CHSO3+H2)贡献相对较少. 将裂解反应总的速率常数拟合为ktotal=1.40×1012T0.15exp(7831.58/T). 此外, 根据统计热力学原理, 预测了所有物种的生成焓(DfHΘ298 K, DfH0 K), 熵(SΘ298 K)和热容(Cp, 298-2000 K), 计算的结果与实验值较接近.  相似文献   

9.
Photolysis of a solution of Cp*RuCp (1) in CF3CO2H generates salt [CpRu(C5Me4CH2)]-(O2CCF3)(2 • O2CCF3). The reaction of compound 1 with oleum at 20 °C through the intermediate dication [η5-(CH2C5Me4)Ru(μ:η55-C5H4C5H5)Ru(C5Me4CH2)-η6]2+ leads to the triply charged cation η7CH2)2C5Me3Ru(μη55-C5H4C5H4)Ru(C5Me4CH2)-η6]3+. Synthesis of pentamethylmetallocene derivatives CpMC5Me4X (M = Ru, Fe; X = CHO, CH2OH, CH2An) has been accomplished. The reactions of 1-hydroxymethyl-2,3,4,5-tetramethylruthenocene with acids CF3CO2H, HBF4, CF3CO2H/NaB[C6H3(CF3)2]4, and picric acid C6H2(NO2)3OH afforded salts 2•X (X = CF3CO2, BF4, B[C6H3(CF3)2]4), and (2,3,4,5-tetram ethylruthenocenyl)methyl picrate [CpRu(C5Me4CH2)-η6][(C6H2(NO2)3O] (2•C6H2(NO2)3O). Structure of the latter was characterized by single crystal X-ray diffraction.  相似文献   

10.
The reactions of Fe(CO)5, Fe(CO)4P(C6H5)3, M(CO)6 (M  W, Mo, Cr), and (CH3C5H4Mn(CO)3 with KH and several boron and aluminium hydrides were investigated. Iron pentacarbonyl was converted quantitatively to K+Fe(CO)4-(CHO) by hydride transfer from KBH(OCH3)3 allowing isolation of [P(C6H5)3]2-Nn+Fe(CO)4(CHO)? in 50% yield. Lower yields were obtained with LiBH(C2H5)3, and other hydride sources gave little or no formyl product. The stability of Fe(CO)4(CHO)? in THP was found to depend on the cation, decreasing in the order [P(C6H5)3]2N+ > K+ > Na+ > Li+. No formyl complexes were isolated and no spectroscopic evidence for formyl formation was observed in the reactions of the other transition metal carbonyls with several hydride sources. Fe(CO)4-P(C6H5)3 gave K2Fe(CO)4 when treated with KHB(OCH3)3. When treated with LiBH(C2H5)3, W(CO)6 gave a mixture of HW2(CO)10?and (OC)5W(COC2H5)?; the latter was methylated to give the carbene complex (OC)5WC(OCH3)C2H5.  相似文献   

11.
The crystal structures of 1,4-diazabicyclo[2.2.2]octane (dabco)-templated iron sulfate, (C6H14N2)[Fe(H2O)6](SO4)2, were determined at room temperature and at −173 °C from single-crystal X-ray diffraction. At 20 °C, it crystallises in the monoclinic symmetry, centrosymmetric space group P21/n, Z=2, a=7.964(5), b=9.100(5), c=12.065(5) Å, β=95.426(5)° and V=870.5(8) Å3. The structure consists of [Fe(H2O)6]2+ and disordered (C6H14N2)2+ cations and (SO4)2− anions connected together by an extensive three-dimensional H-bond network. The title compound undergoes a reversible phase transition of the first-order at −2.3 °C, characterized by DSC, dielectric measurement and optical observations, that suggests a relaxor–ferroelectric behavior. Below the transition temperature, the compound crystallizes in the monoclinic system, non-centrosymmetric space group Cc, with eight times the volume of the ambient phase: a=15.883(3), b=36.409(7), c=13.747(3) Å, β=120.2304(8)°, Z=16 and V=6868.7(2) Å3. The organic moiety is then fully ordered within a supramolecular structure. Thermodiffractometry and thermogravimetric analyses indicate that its decomposition proceeds through three stages giving rise to the iron oxide.  相似文献   

12.
Perfluorinated sulphonic esters RFSO3R'F and fluorosulphates FSO3R'F, are easily obtained by anodic oxidation of iodoperfluoroalkanes R'FI in perfluoroalkane sulphonic acids RFSO3H (RF  CF3, C2F5, C4F9) and fluorosulphuric acid. With di-iodo compound I(CF2)4I, the mono and the diester can be selectively obtained. The alkaline hydrolysis of these esters produces perfluorinated carboxylic compounds. Polyfluorinated iodide R'FCH2CH2I are also oxidized in similar conditions. The mechanism of the electrolytic reaction is discussed.  相似文献   

13.
Trimethyl- and triphenyl-tin(IV) hydroxide act on triphenyl(2-carboxyethyl)-phosphonium hydrochloride, which is made from 3-chloropropionic acid and triphenylphosphine, to release water in the presence of dimethylformamide (DMF) as a catalyst. The water is azeotropically distilled to drive the reaction forward and produce triphenylphosphonopropionbetainetrimethyl- and triphenyl-tin(IV) chlorides in high yield. The latter product also results from the displacement of chloride from triphenyltin(IV) chloride by the phosphobetaine, (C6H5)3P(CH2)2CO2, which is made by treating the phosphonium hydrochloride with bicarbonate, and the compounds [(C6H5)3P(CH2)2CO2Sn(C6H5)3]+X? where X = Cl, Br, I, N3, NCS, NO3, B(C6H5)4 and Co(CO)4 are made in the same way. The acetate salt results from metathesis from the chloride and lead(II) acetate. A double salt, [(C6H5)3P(CH2)2CO2SnR3]+ [R3SnX2]?, is formed for X = Cl, Br and N3 by adding additional (C6H5)3SnX to the already-formed simple salts. Double salts are also obtained from the 11 reactions between the phosphobetaine and triphenyltin(IV) isocyanate and methyldiphenyltin(IV) chloride. The phosphonium chloride double salt could be converted to the thiophosphonium derivative by heating with elemental sulfur in ethanol. The products of these novel nucleophilic displacement reactions are high melting solids. Tin-119m Mössbauer data are consistent with five-coordinated, triorganotin(IV) formulations with the exception of the diphenyl(8-hydroxyquinolinato)tin(IV) chloride salt in which the tin atom is six-coordinated, and the diphenyltin system cis-oriented. The parameters otherwise do not change with the nature of the X group, which is the tetracarbonylcobaltate derivative is tetrahedral by infrared, establishing the ionicity of the products. The chloride exhibits a molar conductivity indicative of a 11 electrolyte in DMF. A bridging acetate structure in the solid is consistent with the lowered ν(CO2) frequencies. The Mössbauer spectra of the double salts give simple doublets of lowered isomer shift (IS) and raised quadrupole splitting (QS) which may arise from a cross-linking ion pairing of the polymer chains in the solid, and the NMR spectra of the two methyltin derivatives shows only a single resonance line and tin satellites which is rationalized by a dynamic exchange process. The products are formulated as associated in carboxylate polymers with dangling triphenylphosphonium cations.  相似文献   

14.
武望婷  胡怀明  王尧宇  史启祯 《化学学报》2005,63(22):2032-2036
在水-乙醇混合体系中, 以2-羰基丙酸水杨酰腙(C10H10N2O4)、2,2-联吡啶(C10H8N2, 简写bipy)与Eu(NO3)3•4H2O反应, 首次培养出黄色单晶[Eu(C10H9N2O4)(C10H8N2O4)(H2O)3]•0.5bipy•3H2O. 该晶体属三斜晶系, 空间群为P-1, 晶胞参数a=0.93392(16) nm, b=1.3100(2) nm, c=1.3895(2) nm, α=97.205(3)°, β=105.411(2)°, γ=106.364(2)°, V=15.35(2) nm3, Z=2, μ=2.118 mm-1, Dc=1.686 Mg/m3, F(000)=786, R=0.0116, wR=0.0507, GOF=0.995. 晶体测试结果表明, 该单晶结构为铕的9配位配合物, 两个2-羰基丙酸水杨酰腙分别以负一价和负二价酮式和三个水分子同时参与配位; 每个2-羰基丙酸水杨酰腙中的羧基氧、酰胺基中的羰基氧和C=N中的氮与Eu3+配位, 形成两个共边的稳定五元环, 另三个配位原子则分别来自三个水分子中的氧原子, 该配合物在空间呈扭曲的单帽四方反棱柱, 而在不对称单位中还有游离的一个2,2-联吡啶分子和三个水分子, 这些游离分子与配位分子之间存在大量分子内和分子间氢键, 整个分子在空间呈三维网状结构. 发光性能测试表明该配合物具有很好的荧光性质.  相似文献   

15.
When liquid SO2 is allowed to react with the tetraalkyltin compounds (CH3)4Sn and (C2H5)4Sn at 60°, disproportionation of sulfur takes place resulting in the formation of the corresponding bis(trialyltin) sulfates, [R3Sn]2SO4, and alkanethiosulfonic acid S-alkyl esters, RSO2SR (R = CH3, C2H5). The course of the reaction is discussed.  相似文献   

16.
In the reaction of C5H5Co(CO)(C3F7)I with isonitriles in the molár ratio 11 the brown complexes C5H5Co(CNR)(C3F7)I are formed. The fluorine atoms of the α-CF2 groups are diastereotopic because of the asymmetric center at the Co atom. With (—)-α-phenylethylisonitrile a pair of diastereoisomers is obtained which could not be separated.C5H5Co(CO)(C3F7)I and C5H5Co(CNR)(C3F7)I react with excess isonitrile with the formation of benzene soluble, yellow salts [C5H5Co(CNR)2(C3F7)]+I?, which can be transformed into the corresponding PF?6 salts. The new compounds were characterised by C, H, N, Co analyses, molecular weight determinations, IR, 1H NMR, 19F NMR, 13C NMR, ESCA and mass spectra.  相似文献   

17.
The bis(μ-dimethylphosphido)dicobalt complex [C5H5Co(μ-PMe2)]2 (II) has been prepared from Co(C5H5 and PMe2H on almost quantitative yield. It has also been made by reduction of [C5H5Co(PMe2H)3]I2 (IV) with NaH and from the reaction of [C5H5(PMe3)Co(μ-CO)2Mn(CO)C5H4Me] with PMe2H. Protonation of II with CF3CO3H in the presence of NH4PF6 produces the PF6? salt of the (μ-hydrido)dicobalt cation [(C5H5Co)2(μ-H)(μ-PMe2)2]+ (V) which reacts with aqueous NaOH to give II. Similar treatment of [C5H5Co(μ-SMe]2 with CF3CO2H/NH4PF6 leads to the formation of [(C5H5Co)2(μ-SMe)3]PF6 (VI). The nucleophilic character of complex II has also been demonstrated in the reaction with SO2, which gives [(C5H5Co)2 (μ-PMe2)2(μ-SO2)] (VII). The crystal and molecular structures of II, the corresponding bis(μ-diphenylphosphido) compound [C5H5Co(μ-PPh2)]2 (III) and the BPh4? salt of V have been determined. In both neutral complexes the Co2P2 cores are similarly puckered, as reflected in the dihedral angle between the CoP2 and P2Co′ planes of 108.1 and 105.0° for R = Me and Ph, respectively. The CoCo bond length and the PP interatomic separations are essentially identical for both dimers. The CoCo bond length in V, 2.517(1) Å, is lower than that in II, 2.542(2) Å. The only obvious structural variation between the unprotonated and the protonated species is the large difference in the degree of canting of the C5H5 rings with respect to each other. The angles between the C5(ring)-centroid and the CoCo line are ca. 150 and 167° in II and V, respectively, which reflects the influence of the bridging hydride ligand in the cationic complex.  相似文献   

18.
Synthesis and characterization of sonic new square-pyramidal pyridine-2-imine complexes [C5,H5,(CO)2,MoNC5,H4,CX=NCH(R1)(R2)]PF6 with X = CH3, C6H5 and chiral amine, 1-phenyl-isobutylamine and amino acid methyl ester H2NCH(COOCH3)(R) with (R) = (CH2C6H5) and (C2H5) have been reported. In combination with Mo chirality (R) and (S), mixtures of two diastereoisomeric pairs of enantiomers with racemic amine and amino acids were obtained which were separated by fractional cystallization. The diastereoisomers differ in the chemical shift of most of their 1H NMR signals and interconvert on heating in acetone-d6 at 80°C for 80 hr and 40°C for 200 hr. On the basis of three conformational determining effects (i) C-H or C-alkyl of the asymmetric centre eclipses the ligand plane, (ii) MC5H5/C6H5 attraction and (iii) MC5H5/alkyl repulsion in order of decreasing significance, the chemical shifts of the C5H5 signals, their differences as well as the diastereoisomer ratio at equilibrium for all the complexes has been rationalised.  相似文献   

19.
Polysulfonyl Amines. LXXII. Triphenylcarbenium and Triphenylphosphonium Di(fluorosulfonyl)amides: Two Crystal Structures with Ordered (FSO2)2N? Sites Treatment of HN(SO2F)2 in CH2Cl2 with Ph3P, Ph3PO or collidine (=B) affords the compounds Ph3PH[(FSO2)2N]? ( 3 ), Ph3PO · HN(SO2F)2, and BH[(FSO2)2N]? ( 7 ). The carbenium salt Ph3C[(FSO2)2N]? ( 5 ), obtained by metathesis of Ph3CBr with [(C6H6)AgN(SO2F)2] in CH2Cl2, crystallizes from chloroform/petroleum ether as a monosolvate Ph3C[(FSO2)2N]? · CHCl3 ( 6 ). In presence of a sterically hindered base, viz. collidine, 5 is a suitable reagent for the tritylation of molecules containing weakly activated H atoms (e. g.: MeCN → Ph3CCH2CN, acetone → tritylacetone; co-product: 7 ). The crystal structures of the ionic solids 3 (monoclinic, space group P21/n) and 6 (monoclinic, P21/c) were determined by X-ray diffraction at ?130°C; the structure refinements were not impaired by the notorious tendency of the (FSO2)2N moiety towards crystallographic disorder. As in the known structure of the tetraphenylarsonium salt, the anion of 3 and 6 adopts a staggered conformation of approximately C2 symmetry (averages of all values: S? N? S 121.4°, N? S 156.2, S? O 141.6, S? F 156.6 pm). The crystal packing of 6 displays a three-centre C? H(…?O)2 hydrogen bond between the CHCl3 molecule and two oxygen atoms of a single anion, resulting in a six-membered ring [R12(6) pattern; H …? O 234 and 262 pm]. The crystal of 3 contains one-dimensional arrays of alternating cations and anions connected by a three-centre P? H(…?O)2 bond [C(6) pattern; H …? O 237 and 254 pm]. The Ph3C cation of 6 is propeller-shaped, with three coplanar central bonds (mean C? C 144.5 pm) and interplanar angles of 52.7, 56.4 and 60.1° between the phenyl groups.  相似文献   

20.
trans-[IrCl(C2R2)(PPr3i)2] complexes are prepared from [(C8H14)2IrCl]2, PPr3i and C2R2 (R = H, Me, Ph) via the intermediate [IrCl(PPr3i)2]. With phenylacetylene, a mixture of two isomers, trans-[IrCl(PhC2H)(PPr3i)2] and IrHCl(C2Ph)(PPr3i)2 is formed which reacts with pyridine to give IrHCl(C2Ph)(py)(PP3i)2. Reaction of trans-[IrCl(C2Ph2)(PPr3i)2] with NaC5H5 yields the compound C5H5Ir(C2Ph2)PPr3i (VI) which is transformed via the vinyl complex C5H5Ir(CPhCHPh)(OCOCF3)PPr3i (VII) into the iridaindene derivative IX. Using VII as the starting material, C5H5Ir(OCOCF3)2PPr3i, C5H5Ir(CPhCHPh)(I)PPr3i and C5H5Ir(CPhCHPh)(CH3)PPr3i are also obtained. Treatment of VI with Br2 and I2 respectively yields the complexes C5H5IrX2PPr3i) (XII, X = Br; XIII, X = I), of which XIII reacts with CH3MgI to give C5H5Ir(CH3)2PPr3i.  相似文献   

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