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1.
《Journal of Coordination Chemistry》2012,65(18):2949-2956
Reactions between AgX (X = OTf, NO3) and ylides of the type Ph3P = CHC(O)C6H4-4-R (R = F, Br, OMe) in molar ratio 1 : 2 lead to complexes [Ag{CH(PPh3)C(O)C6H4-4-R}]X (1–4); X-ray structure determinations have been carried out on 4. The IR and NMR data of the products formed by reaction of Ag(I) with the ylides are consistent with C-bounded ylides. Analytical data indicate 1 : 2 stoichiometry between the ylide and Ag(I) in the products. The molar conductivities of these complexes are within the range for 1 : 1 electrolytes. Crystallographic data for 4 are: crystal system, triclinic; space group, P 1, a = 12.1151(4), b = 13.8989(5), c = 15.4855(5) Å, β = 102.676(3)°, V = 2477.82(15) Å3, Z = 2. 相似文献
2.
Miller G. Makramalla Monica T. Diab Cody N. Sherren Arthur D. Hendsbee Jason D. Masuda Katherine N. Robertson 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1537-1554
Abstract The reactivity of ketenylidenetriphenylphosphorane (1) with the protic reagents 2,4,6-trimethylphenol (7), 2,6-di-tert-butyl-4-methylphenol (8), and diphenylamine (9) has been explored. Three novel carbonyl-stabilized ylides have been synthesized and characterized. Crystal structures were obtained for Ph3PCHC(O)O(C6H2Me3) (11), Ph3PCHC(O)O(C6H2t-Bu2Me) (12), and Ph3PCHC(O)NPh2 (13), respectively. These products were then methylated in an attempt to develop a new route to low-valent carbon compounds. Crystals of [Ph3PCH(CH3)C(O)O(C6H2Me3)]I (14) were isolated and characterized but this route did not prove to be synthetically useful, at least toward the goal of preparing low-valent carbon-centered materials. Finally, 1 was also reacted with the bulky tin reagent, bis[bis(trimethylsilyl)amido]tin(II), in the presence of 2,4,6-trimethylphenol. A complex mixture of products was obtained, from which crystals of an unusual chelated tin compound (15) were isolated and characterized using X-ray crystallography. 相似文献
3.
Borisova I. V. Nechaev M. S. Khrustalev V. N. Zemlyanskii N. N. Ustynyuk Yu. A. 《Russian Chemical Bulletin》2002,51(5):721-753
The review surveys the data on the reactions of phosphorus and arsenic ylides with compounds containing E=X bonds (E = C, Si, Ge, or Sn; X = C or S), cyclic oligomers (R2ES)n (n = 2 or 3), and heavier analogs of carbenes. These reactions give rise to two new classes of heteroorganic betaines containing the (+)E15—C—E14—X(–) (I) and (+)E15—C—E14(–) (II) (E15 = P or As; E14 = Si, Ge, or Sn; X = C or S) structural fragments. Procedures for the synthesis of these compounds, their reactivities, the X-ray diffraction structures, and the electronic structures established by high-level quantum-chemical calculations are considered in detail. The carbon analogs of betaines of type I, viz., compounds bearing the (+)P—C—C—X(–) fragment (III), are also discussed. The latter were long considered as possible intermediates in the reactions of compounds containing the polar C=X bond (X = C, O, S, NR, etc.) with phosphorus ylides (classical Wittig and Corey—Chaykovsky reactions and related processes). 相似文献
4.
Seyyed Javad Sabounchei Mohammad Panahimehr Sadegh Salehzadeh Mehdi Bayat Hamid Reza Khavasi David Morales-Morales 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1743-1758
Abstract The reaction of Ph2PCH2PPh2 (dppm) with 4-methylphenacyl bromide and 2-(bromoacetyl)naphthalene in chloroform produce the new phosphonium salts [Ph2PCH2PPh2CH2C(O)C6H4Me]Br (1) and [Ph2PCH2PPh2CH2C(O)C10H7]Br (2). Further, by reaction of the monophosphonium salts of dppm with the strong base Et3N the corresponding bidentate phosphorus ylides, Ph2PCH2P(Ph)2 = C(H)C(O)C6H4Me (3) and Ph2PCH2P(Ph)2 = C(H)C(O)C10H7 (4) were obtained. The reaction of these ligands with mercury(II) halides in dry methanol led to the formation of the mononuclear complexes {HgX 2[(Ph2PCH2PPh2C(H)C(O)C6H4Me)]} [X = Cl (5), Br (6), and I (7)] and {HgX 2[(Ph2PCH2PPh2C(H)C(O)C10H7)]} [X = Cl (8), Br (9), and I (10)]. Characterization of the obtained compounds was performed by elemental analysis, IR, 1H, 31P, and 13C NMR spectra. The structure of compounds 3 and 10 are unequivocally determined by single crystal X-ray diffraction techniques. X-ray analysis of 10 reveals the presence of mononuclear complex containing Hg atom in a distorted tetrahedral environment. In all complexes, the title ylides are coordinated through the ylidic carbon and the phosphine phosphorus. Computational studies on ligand 4 and complexes 8, 9, and 10 at DFT (B3LYP) level of theory are also reported. It was shown that the formation of P,C-coordinated 1+1 complex 10 is energetically more favored than corresponding P,P-coordinated 1+2 product. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the following free supplemental files: Additional figures] 相似文献
5.
T. I. Nazarenko L. E. Deev V. G. Ponomarev N. I. Novosel'tseva N. B. Pospelova K. I. Pashkevich 《Russian Chemical Bulletin》1991,40(3):586-588
Nucleophilic iodofluorination of perfluorovinyl methyl (I) and perfluorovinyl propyl (II) ethers by iodine chloride in nitrobenzene or sulfolan afforded 1-iodoperfluoro-1-methoxyethane (III) and 1-iodoperfluoro-l-propoxyethane in yields of 65 and 77%, respectively. In addition to compound (III), the reaction of perfluorovinyl methyl ether afforded two side products: l-iodo-2-chloroperfluoro-1-methoxyethane and 2-iodo-l-chloroperfluoro-1-methoxyethane. The latter products are formed via a radical reaction, which takes place under drastic conditions. On the basis of quantum chemical calculations of (I), (II), and the two anions formed from (I), CF3OCFCF3 (VI) and CF3OCF2CF2 (VII), it is proposed that nucleophilic iodofluorination of perfluoroalkyl vinyl ethers involves the formation of thermodynamically more stable anions. The higher reactivity of (I) compared with (II) is in accord with the energy of the lowest unoccupied molecular orbitals and the charge density on the CF2 carbon atoms.19F NMR spectra of the synthesized products are shown.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 669–672, March, 1991. 相似文献
6.
Shi-Zheng Zhu 《Heteroatom Chemistry》1994,5(1):9-18
Phenyliodonium bis(perfluoroalkanesulfonyl) methides PhI+ −C(SO2RF)2 ( 3 ) were prepared by the reaction of bis(perfluoroalkanesulfonyl)methanes with diacetoxyiodobenzene. The photochemical reactions of 3 with alkenes, methanol, bromine, and benzene gave the corresponding addition or insertion products. When 3 was irradiated in the presence of methyl sulfide, pyridine, and triphenylphosphine, it afforded the ylides containing the bis(perfluoroalkanesulfonyl)methylene functionality, Y+ −C(SO2RF)2. In these reactions the bis(perfluoroalkanesulfonyl)carbene intermediate (RFSO2)2C: may be involved. Irradiation or heating of 3 in DMSO gave a 1 : 1 complex, the structure of which was confirmed by X-ray diffraction analysis. Bis(perfluoroalkanesulfonyl)-methylene dimethyloxosulfonium ylides Me2(O)S+ −C(SO2RF)2 were obtained by air oxidation of bis(perfluoroalkanesulfonyl)methylene dimethylsulfonium ylides. 相似文献
7.
Hubert Schmidbaur Graham A. Bowmaker Ulrich Deschler Cornelia Dörzbach Rudolf Herr Beatrix Milewski-mahrla 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):167-170
Abstract Structural data of phosphorus ylides are summarized and discussed. Conformational preferences in solution and in the solid state, as followed by NMR spectroscopy and X-ray diffraction, indicate a strong gauche effect for the lone pairs of electrons at the ylidic carbon atom. One- and two-electron oxydation of ylide carbanions is accomplished with copper(II) as the oxidant, leading to oxidative coupling or to halogenation, respectively. 相似文献
8.
Ghasem Marandi Malek Taher Maghsoodlou Reza Heydari Sayyed Mostafa Habibi-Khorassani Roya Kabiri Zahra Gharechahi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1395-1403
Protonation of the reactive 1:1 intermediates produced in the reactions between triphenylphosphine and dialkyl acetylenedicarboxylates by 1-amino-anthraquinone or 1,5-diphenylcarbazone as a core dye leads to vinyl phosphonium salts, which undergo Michael addition with conjugate base of NH compounds to produce stable phosphorus ylides as novel dyes in fairly good yields. These ylides can exist in two geometrical isomers (Z) and (E) for 3, because the negative charge of the ylide moiety of these compounds are strongly conjugated with the adjacent carbonyl group. Rotation around the carbon–carbon double bond is slow in the (Z) and (E) geometrical isomers on the NMR time scale at ambient temperature. These compounds are assigned by their IR, 1H, 13C NMR spectral data as well as their mass spectroscopic data. 相似文献
9.
Sudip Baguli Subham Sarkar Soumajit Nath Dr. Dibyendu Mallick Dr. Debabrata Mukherjee 《Angewandte Chemie (International ed. in English)》2023,62(47):e202312858
Azomethine ylides are typically in situ generated synthons for making N-heterocycles through cycloaddition reactions. But an offbeat aspect about them is the isomeric nature of aldiminium-based azomethine ylides and (alkyl/aryl)(amino)carbenes, interconvertible by a formal 1,3-H+ transfer. Herein, two thermally robust azomethine ylides with a N-appended picolyl sidearm are isolated, which cyclize to pyaziridines at 80 °C but unprecedentedly result N−picoCAAC-CuCl (CAAC=cyclic(alkyl)(amino)carbene) complexes when heated with CuCl at merely 60 °C. The pendant Npy, as revealed by computational analysis, plays a crucial role in this unusual 1,3-H+ shift using a deprotonation-protonation sequence, as well as in placing the CuCl at the carbenic site in tandem. The softer nature of Cu(I) is also critical. Chelating CAACs are rare and one with a N-tethered additional donor is priorly unknown. Both N-picoCAAC and pyaziridine are bidentate chelators giving highly active cationic Rh(I) catalysts for hydrosilylating unactivated olefins by Et3SiH. Notably, the pyaziridine-Rh(I) is superior than the N-picoCAAC-Rh(I) catalyst. 相似文献
10.
《Analytical letters》2012,45(7):741-752
Abstract The oxidation of the 1, 2, 3, 4-thiatriazol-5-thiolate ion CS2 N? 3by, permanganate ions in an alkaline medium was investigated. The pseudo-halide undergoes a quantitative seventeen-electron change reaction yielding sulphate, nitrogen and carbon dioxide as final products. Despite the similar chemical behavior exhibited by thiocyanate and CS2N? 3 ions the experimental data strongly suggested that the oxidation reactions of the pseudo-halides dealt with in this study do not follow the same mechanism. On the basis of this reaction an oxidative analytical method was developed for the CS2N? 3. The pseudo-halide is oxidized by an excess of permanganate ions. The remaining oxidant is titrated with standardized thalium (I) or hexacyanoferrate (II) solutions. Considerable improvements over former procedures were achieved employing two polarized platinum electrodes to detect the end point, by potentiometry. The method proposed here is simple, precise, accurate, rapid and allows the determination of pseudo-halide concentrations down to 1 × 10?3 M. 相似文献
11.
Wolfgang Dietzsch Joachim Sieler Wolfgang Meiler Wolfgang Robien 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):293-300
Abstract The oxidation products of thioseleno-carbamate ions R2NCSSe? are, in contrast with the homologous selenuramdiselenides, stable red, highly crystalline diselenides (R2N = Et2N, morpholyl, pyrrolidyl, Bz2N) or yellow (cyclohexyl2N). The 77Se NMR spectra show one signal with chemical shifts between 1060 and 1125 ppm (referenced to Ph3PSe). The x-ray structures of the tetraethyl (I) and tetracyclohexyl (II) compounds show unexpected differences. Whereas (I) contains an inversion center bisecting a planar NC(S)Se-Se(S)CN unit, we found for (II) a dihedral angle of 80.4 between two very different cyclohexyl2 halves: S(1)-C(1)-Se(1) = 103.0° and S(2)-C(2)-Se(2) = 119.1°, respectively. 相似文献
12.
Yong-Miao Shen Peng-Cheng Lv Ming-Zhu Zhang Hui-Quan Xiao Li-Ping Deng Hai-Liang Zhu Chen-Ze Qi 《Monatshefte für Chemie / Chemical Monthly》2011,31(10):521-528
Abstract
Pyrrolo[1,2-a]imidazole and pyrrolo[2,1-b]thiazole derivatives were synthesized in a one-pot procedure by [3 + 2] cycloaddition reactions of the corresponding imidazolium ylides and thiazolium ylides with an alkene followed by oxidative aromatization of the primary cycloadducts under the action of the mild oxidant tetrakispyridinecobalt(II) dichromate. Antiproliferative activity of 14 new bicyclic N-fused heterocycles against the human hepatocellular liver carcinoma (Hep-G2) cell line were examined by the MTT method. Some of the compounds showed favorable antiproliferative activity, especially compound 3i displayed potent antiproliferative activities with an IC50 value of 0.36 μg/cm3. 相似文献13.
《Journal of Coordination Chemistry》2012,65(4):257-262
Abstract The 57Fe Mössbauer effect for the solid complex FeLCl2·H2O (L=10-phenanthroline-2-carbothioamide) has been studied between 4.2°K and 298°K. Two overlapping doublets (I and II) are observed, their relative intensity being strongly temperature dependent. The doublets are characterized by δEQ(I)=0.53 mm sec?1, δIS(I)=+ 0.22 mm sec?1 and δEQ(II)=1.33 mm sec?1, δIS(II)=+0.23 mm sec?1 at 4.2°K. In conjunction with magnetic data, the Mössbauer spectra are interpreted in terms of a singlet-triplet spin transition of the central iron(II) ion. In an applied magnetic field at 4.2°K, Hint=0, VZZ(I)>0, and VZZ(II)>0. The results are consistent with optical electronic and infrared vibrational spectra. 相似文献
14.
The induced halogenation and hydroxyhalogenation of alkyl cyclohexenyl ketones in a system [MHlg + HHlg or HHlg]-H2O2 or in NaOCl was performed and optimum reaction conditions were established. Under mild conditions the electrophilic addition of the halogen or the acid occurred at the multiple bond of the ring with the formation of the corresponding dihalo or hydroxyhalo derivatives of cycloaliphatic ketones. From the compounds obtained epoxy- and dioxyketones of aliphatic series were prepared. Chloro(bromo)hydrins of ketones from the alkylcyclohexane series and oxiranes based thereon are reactive compounds and can be employed as synthons in the organic synthesis. 相似文献
15.
Summary Nickel(II) xanthates react with amines to form nickel(II) dithiocarbamates and thiourethanes, both products of nucleophilic substitution at the sp2 carbon atom. If the reaction is conducted under carbon monoxide the nickel and sulphur-containing byproduct of thiourethane formation is transformed partly into Ni(CO)4. 相似文献
16.
D. Saravanabharathi T. S. Venkatakrishnan M. Nethaji S. S. Krishnamurthy 《Journal of Chemical Sciences》2003,115(5-6):741-749
Rhodium(I) complexes of the hybrid ylide-phosphine ligands, Ph2P(CH2)
n
PPh2(CHC(O)C6H5) (n = 1: dppm-yl, or 2: dppe-yl) have been synthesised from [Rh(μ-C1)(COD)]2 (COD = 1,5-cyclooctadiene) and characterized by NMR spectroscopic and X-ray structural methods. The dppe-yl behaves as an
ambidentate ligand; it functions as a monodentate P-donor ligand with a dangling ylidic carbon in the neutral chloro complex,
[(COD)Rh(Cl)(dppe-yl)] (1), whereas replacement of the chloride by a non-coordinating counter anion results in the formation of the complexes, [(COD)Rh(L-L’)]+ (L-L’ = dppe-yl (2) or dppm-yl (3)) respectively in which the ligands are bonded to the metal via the phosphorus and the ylidic carbon atoms. The 1,5-cyclooctadiene
(COD), present in the Rh(I) precursor, remains intact in the products. The structures of1,2 and3 have been confirmed by X-ray crystallography.
Dedicated to Professor C N R Rao on his 70th birthday 相似文献
17.
C60-吡咯烷衍生物的合成及非线性光学性质的研究 总被引:1,自引:0,他引:1
通过富勒烯C60与肌氨酸和有机醛化合物的1,3-偶极环加成反应, 获得了九种含不同有机功能基团的C60吡咯烷衍生物1~9, 用1H NMR, 13C NMR, FTIR, UV-vis和FAB-MS进行了结构表征; 利用皮秒激光光源, 采用z扫描技术测定了分子的三阶非线性超极化率γ(3), 结果显示: 化合物3 (γ(3)=4.14×10-33 esu)具有最大的三阶非线性光学系数, 说明增加噻吩共轭链的长度, 使三阶非线性活性增加; 对具有相同共轭链的C60-噻吩吡咯烷衍生物(2, 5, 1和4), 吸电子取代基减小了三阶光学非线性活性, 给电子基增大了三阶光学非线性活性; 同时发现喹啉环2-位键联(7)比4-位(8)有更好的三阶光学非线性活性. 相似文献
18.
T. Nishimura H. Iwasaki M. Takahashi M. Takeda 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(3):499-502
127I Mössbauer spectra for the phenyliodonium ylides were measured at 20 K. The valence electron populations (Ns, Nx-z) and the charge number (ZI) for iodine atom are estimated from the Mössbauer parameters. The obtained populations were very close to those of diphenyliodonium chloride having two I-C primary bonds. To examine the possibility of some double bond character, the electron populations for the case of Nz = 1.90 are estimated. In this case, the ZI values become larger as 1.2-1.3, and these values were unreasonably large because the values are close to those of PhICl2, PhI(OAc)2 having electron withdrawing ligands. Thereby, 127I Mössbauer parameters suggest little double bond character for phenyliodonium ylides. 相似文献
19.
《Analytical letters》2012,45(17):1963-1972
Abstract A spectromeric study of the reaction of the Zr(IV) ions with Mandelazo I was carried out. Absorption spectra revealed that the maximum absorption of the zirconium compound appears at a wavelength (316 nm) different from the maxima of the reagent (253 and 390 nm). Beer-Lambert law is followed for zirconium concentrations of the order of 8.8x 10?5 M (i.e. 8 μg Zr (IV)/mL). Possible interferences of ions such as Be(II), Cu(II), Zn(II), Al(III), Th(IV), U(VI), Mn(II), Fe(III), Co(II) and Ni(II) were investigated in connection with some masking agents such as SO4 2- and C2O4 2-. Also, the solid state Zr(IV)-Mandelazo I compound was prepared and characterized by nitrogen and thermogravimetric analyses. 相似文献
20.
Masao Kato Hiroshi Urabe Yoshinao Oosawa Taro Saito Yukiyoshi Sasaki 《Journal of organometallic chemistry》1976,121(1):81-91
Cationic palladium(II) and platinum(II) complexes with chelate ylides and neutral ligands of the type, [MCl (Y) (L)]+BPh4? (M Pd or Pt; Y bdep or bdmp*; L = 4-methylpyridine, 3,5-dimethylpyrazole, PPh3, PCy3, PMePh2, P(OMe)3, AsPh3 or SbPh3) and [M(bdep) (4-methylpyridine)2] (BPh4)2 (M = Pd or Pt) were prepared and characterized by means of infrared and 1H NMR spectra. 相似文献