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1.
Abstract

α-Chlorotoluene (1) reacts with elemental sulfur in liquid ammonia affording dibenzyl disulfide (2), dibenzyl trisulfide (3), dibenzyl tetrasulfide (4), dibenzyl pentasulfide (5) and benzylidene benzylimide (6) at a low temperature such as 20°C. This reaction is presumed to be initiated by the nucleophilic attack of ammonium thioaminohydroxylate, “H2NS-NH4 +,” or dithioaminohydroxylate, “H2NSS-NH4,” formed upon treating elemental sulfur in liquid ammonia, on α-chlorotoluene (1). Benzylidene benzylimide (6) is presumed to be formed from benzylamine, which can be formed by treatment of α-chlorotoluene (1) with ammonia.  相似文献   

2.
Density functional theory was used to study the structure of various isomers of (Me2Cu)Li (1), (Me2Cu)Cu (2), (Me2Cu)Li · 2Me2O (3), and (Me2Cu)Cu · 2Me2S (4) in the gas phase. Isomers of 1 and 3 were shown to be typical cuprates, whereas isomers of 2 and 4 should rather be treated as unsolvated and solvated methylcopper dimers, respectively. The reasons for the difference between structures 2, 4 and 1, 3 were considered. The energies of solvation of 1 by two dimethyl ether molecules (∼34 kcal/mol) and of 2 by two dimethyl sulfide molecules (∼36 kcal/mol) and the dissociation energies of all the compounds to the dimethylcuprate anion and the corresponding cation were calculated. The energies of solvation of 1 and 2 being almost equal, the transformation of 2 into 4 decreased the dissociation energy much more substantially than the transformation of 1 into 3.  相似文献   

3.
Abstract

The reaction of the metalhydrides C5R5(CO)3Mo-H (R=H (la), Me (lb) with P(NMe2)3 leads to the metal-phosphorus double-bonded species 2a,b via the intermediate formation of C5(CO)2 (Me2N)3P)Mo-H, which can only be identified spec-troscopically in solution.  相似文献   

4.
Abstract

The syntheses of the P(III) analogues of cyclophosphamide, isophosphamide and triphosphamide are reported. These compounds (4–6, respectively) polymerize easily at room temperature but are sufficiently stable in solution to react with Cl2Pt(NCPh)2, forming cis-Cl2Pt(4)2, cis-Cl2Pt(5)2 and cis-Cl2Pt(6)2 (complexes 9–11, respectively). Complex 10 can also be made by condensing cis-Cl2Pt[ClPN(CH2CH2Cl)CH2CH2CHO]2 with ClCH2CH2NH2, while an alternate route to 9 and 11 is afforded by the condensation of cis-Cl2Pt[Cl2PN(CH2CH2Cl)2]2 with H2NCH2CH2CH2OH and ClCH2CH2NHCH2CH2CH2OH, respectively. Complexes 9–11 exist in two diastereomeric configurations and these can be separated in the cases of 9 and 11 by column chromatography. 31P NMR spectral data for the complexes are discussed and the results of NCl antitumor screening are presented.  相似文献   

5.
Chalcone-derived 3-phenyl-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCTPh) (1), 3-(4-chlorophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4ClPh) (2), 3-(4-bromophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4BrPh) (3), and 3-(4-nitrophenyl-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4NO2Ph) (4) were obtained as well as their gallium(III) and zinc(II) complexes [Ga(PyCTPh)2]NO3 (Ga1), [Ga(PyCT4ClPh)2]NO3 (Ga2), [Ga(PyCT4BrPh)2]NO3 (Ga3), [Ga(PyCT4NO2Ph)2]NO3 (Ga4), [Zn(PyCTPh)2] (Zn1), [Zn(PyCT4ClPh)2] (Zn2), [Zn(PyCT4BrPh)2] (Zn3), and [Zn(PyCT4NO2Ph)2] (Zn4). The chalcones, thiosemicarbazones, and zinc(II) complexes were not active against Pseudomonas aeruginosa. The thiosemicarbazones proved to be more active than the parent chalcones against Staphylococcus aureus and Candida albicans. Coordination to zinc(II) resulted in activity improvement of most thiosemicarbazones against S. aureus. Coordination to gallium(III) significantly improved the antimicrobial activity of all thiosemicarbazones against the studied micro-organisms, suggesting this to be an effective strategy for antimicrobial activity enhancement.  相似文献   

6.
The alkoxides of molybdenum and other heavy transition elements such as Ta or Nb were found to be unreactive towards each other. The bimetallic derivatives could be obtained either via partial hydrolysis that gave Mo2Ta4O8(OMe)16 (I) or via partial thermolysis that provided access to Mo4Ta2O8(OiPr)14 (II), Mo3Ta2O8(OiPr)10 (III), Mo4Ta4O16(OiPr)12 (IV), Mo4Nb2O8(OiPr)14 (V) and Mo4W2–x Mo x O10(OiPr)12 (VI). IVI can be isolated only from hydrocarbon media as the presence of alcohols leads to precipitation of insoluble homometallic derivatives of molybdenum. The cathodic reduction of MoO(OR)4 (R = Me, Et) in the presence of LiCl and M(OR)5 (M = Nb, Ta) leads only to formation of LiMo2O2(OMe)7(MeOH) (VII) or LiMo2O2(OEt)7 (VIII) respectively.  相似文献   

7.
The reaction of [Na2PdCl4] with 3,5-bis(2-pyridoxy)toluene (LpyH) in acetic acid yields the cyclometalated complex [PdCl(Lpy-N, C, N)] (1). Complex 1 can be further converted into neutral species by metathesis reaction exchange of chloride by either iodide or thiocyanate to yield [PdX(Lpy-N, C, N)] (X = I (2), SCN (3)). The chloride can be replaced by neutral ligands like pyridine or acetonitrile in the presence of silver tetrafluoroborate to give the corresponding cationic compounds [PdL(Lpy-N, C, N)]BF4 (L = Py (4), MeCN (5)). In contrast, the reaction of [Na2PdCl4] with 3,5-bis(3, 5-dimethylpyrazol-1-ylmethyl)toluene (LpzH) under analogous conditions yields the neutral complex [PdCl2(LpzH-N, N)](6) with the ligand bidentate N,N-donor. The cyclometalated palladium complex [PdCl(Lpz-N, C, N)] (7) was prepared by the reaction of Pd(OAc)2 with LpzH in acetic acid followed by a metathetic reaction with lithium chloride in acetone/water. Complexes 1, 6, and 7 in the presence of methylaluminoxane (MAO) lead to an active catalyst for the polymerization of ethylene.  相似文献   

8.
Abstract

A new method of silica dissolution is described. It involves the formation of a stable SiF4 · n ROH complex (1, 1a) just from SiO2 and anhydrous alcoholic HF generated in situ from commercially available hexafluoropropene oxide. Alcoholic SiF4 complexes can be easily converted to different organosilicon compounds of the type SiF4L2 and (LH)2SiF6 [L = 1,10-phenantroline (2a), 2,2′-dipyridyl (2b), Me2SO (2c), pyridine (2d), triethanolamine (3a)]. Different silica-containing compounds can be used in this strategy—silicagel, sand, alumosilicates, and even rice husk.

GRAPHICAL ABSTRACT  相似文献   

9.
Mononuclear Co(II), Zn(II) and Cd(II) complexes derived from bidentate or tridentate N,N′,N-bis((1H-pyrazol-1-yl)methyl)amines (Ln = LA, LB), where LA is N,N-bis((1H-pyrazol-1-yl)methyl)-3-methoxypropan-1-amine and LB is 3-methoxy-N,N-bis((3,5-dimethyl-1H-pyrazol-1-yl)methyl)propan-1-amine, have been synthesized and characterized. The geometry at Co(II) and Cd(II) for [LACoCl2], [LBCoCl2] and [LBCdBr2] with N,N′,N-tridentate ligands (Ln = LA, LB) can be described as a distorted trigonal bipyramid achieved by coordinative interaction of Npyrazole, two halides and the nitrogen of amine moiety. However, the molecular structure of four-coordinate [LAZnCl2] can be best described as tetrahedral, resulting in an eight-membered chelate ring. [LACoCl2] polymerized methyl methacrylate in the presence of modified methylaluminoxane at 60 °C and resulted in poly(methylmethacrylate) (PMMA) with higher molecular weight and narrower polydispersity index compared to the other synthesized complexes. However, all the synthesized complexes yielded syndiospecific PMMA, characterized using 1H NMR spectroscopy, with ca. 0.70.  相似文献   

10.
Organometallic tungsten selenido complexes of the type [cpW(CO)3]2Sem; m = 2 (1), 3 (2), 4 (3), can be easily synthesized via insertion of selenium into the alkali-metal tungsten bond of LiWcp(CO)3 in appropriate ratios and subsequent oxidation of the produced W-selenolates with O2/SiO2. In contrast, reactions of K2Se6 with [cpW(CO)3Cl] and 18-crown-6 in DMF lead to a mixture óf [cpW(CO)3]2Se4 (3), the η1 Se-bonded selenocarbamato complex [cpW(CO)3SeC(O)NMe2] (4) and the ionic complex [(18-crown-6)K]+[cpW(Se4)2]? (5). The crystal structures of 3 and 4 together with their 77Se NMR data are presented.  相似文献   

11.
Two mononuclear copper(II) complexes, [Cu(C4H3N2O2)2?·?4H2O] (1) and [Cu(C12H11N2O2Cl2)2] (2), were synthesized and structurally characterized by single-crystal X-ray analysis. The copper(II) adopts a square-planar environment in 1, while the geometry in 2 can be described as distorted square-pyramidal. Complexes 1 and 2 were evaluated for their inhibitory activities against jack bean urease in vitro and both were found to have strong inhibitory activities comparable to that of acetohydroxamic acid. A docking simulation was performed to position 2 into the jack bean urease active site to determine the probable binding conformation.  相似文献   

12.
Heating 1-alkyl- or 1-aryldihydro-6-methyl-2(1H)-pyrimidinethiones5, 6 in an inert medium causes rearrangement to 4-alkylamino-(4-arylamino-)-5,6-dihydro-2(1H)-pyridinethiones11, 12, probably via the methylene form29, by thermal heterolysis of the N1/C2 bond and exchange of the alkylamino (arylamino) group 1 through the carbon atom of the methylene group 6. The aminodihydropyridinethiones11, which can be regarded as cyclic derivatives of 3-aminothiocrotonamide, react with bistrichlorophenylmalonate under diacylation, and with formaldehyde and primary amines to yield aminodialkylation products of the enamine system, tetrahydro-4-hydroxy-7,7-dimethyl-5-thioxopyrido[4,3-b]pyridine-2(1H)-ones13, 14 and hexahydro-7,7-dimethylpyrido[4,3-d]pyrimidine-5(6H)-thiones18, 19, 21 respectively. H2O2 converts11 to the corresponding 4-aminodihydro-2(1H)-pyridones22, which can be reconverted into11 with P4S10.11 reacts with alkyl halides to 2-alkylthiodihydropyridines23, 24, 25. The mechanism of the methylpyrimidine-pyridine rearrangement is discussed.  相似文献   

13.
New organotin(IV) carboxylates, [n-Bu2SnL2] (1), [Et2SnL2] (2), [Me2SnL2] (3), [n-Oct2SnL2] (4), [n-Bu3SnL] n (5), [Me3SnL] n (6), and [Ph3SnL] n (7), where L?=?3-(4-bromophenyl)-2-ethylacrylate, were synthesized and characterized by elemental analysis, FT-IR, and multinuclear NMR (1H, 13C, and 119Sn). Spectroscopic studies confirm coordination of L to the organotin moiety via COO group. Single-crystal X-ray analysis reveals bridging mode of coordination in 6. Packing diagram established a supramolecular cage-like structure for 6 due to Sn–O interactions (3.287?Å). Subsequent antimicrobial activities proved them to be active biologically.  相似文献   

14.
New silicon-, germanium-, and tin-containing imido-alkyl molybdenum complexes (ArN)2Mo(CH2EMe3)2 (Ar is 2,6-diisopropylphenyl; E = Si (1), Ge (2), Sn (3)) were prepared in the crystalline state in 58–66% yields by the reactions of the (ArN)2MoCl2(DME) complex with alkyllithium derivatives Me3ECH2Li (E = Si or Ge) or the Grignard reagents Me3ECH2MgCl (E = Ge or Sn). The structures of complexes 13 and the known analog (ArN)2Mo(CH2But)2 (4) were established by X-ray diffraction analysis. Complexes 13 were found to be isostructural. The coordination environment about the Mo atom can be described as a distorted tetrahedron. Complex 4 has a similar structure. The Mo-C distance tends to decrease with increasing electron donating ability of the EMe3 group.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 597–600, March, 2005.  相似文献   

15.
Thermal energy gaps, ΔEs–t; enthalpy gaps, ΔHs–t; and Gibbs free energy gaps, ΔGs–t between the singlet (s) and triplet (t) states of X2C2H2C, 1X (X = CH, N, P, As, and Sb) were calculated and compared with those analogues, XC2H3C, 1′X (X = N, P, As, and Sb) at the B3LYP/6-311++G** level of theory. Density functional theory (DFT) calculations indicated that the ΔGs-t, for 1X (X = N and P) should be lower with respect to their monosubstituted 1′X . In contrast, the ΔGs-t for 1X (X = As and Sb) should be larger with respect to 1′X . The ΔGs-t for 1X and 1′X were increased in the following order: 1Sb > 1As > 1C > 1P > 1N ; 1′Sb > 1′As > 1′P > 1C > 1′N , respectively.

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 free supplemental file.  相似文献   

16.
The radical–molecule reaction mechanism of CH2Cl with NO2 has been explored theoretically at the B3LYP/6–311G(d,p) and MC–QCISD (single-point) levels of theory. Our results indicate that the title reaction proceeds mostly through singlet pathways, less go through triplet pathways. The initial association between CH2Cl and NO2 is found to be the carbon-to-nitrogen attack forming the adduct a H2ClCNO2 with no barrier, followed by isomerization to b 1 H2ClCONO-trans which can easily convert to b 2 H2ClCONO-cis. Subsequently, the most feasible pathway is the C–Cl and O–N bonds cleavage along with the N–Cl bond formation of b (b 1 , b 2 ) leading to product P 1 CH2O + ClNO, which can further dissociate to give P 5 CH2O + Cl + NO. The second competitive pathway is the 1,3-H-shift associated with O–N bond rupture of b 1 to form P 2 CHClO + HNO. Because the intermediates and transition states involved in the above two favorable channels all lie below the reactants, the CH2Cl+NO2 reaction is expected to be rapid, as is confirmed by experiment. The present results can lead us to understand deeply the mechanism of the title reaction and may be helpful for further experimental investigation of the reaction.  相似文献   

17.
Heating 1-alkyl- or 1-aryldihydro-6-methyl-2(1H)-pyrimidinethiones5, 6 in an inert medium causes rearrangement to 4-alkylamino-(4-arylamino-)-5,6-dihydro-2(1H)-pyridinethiones11, 12, probably via the methylene form29, by thermal heterolysis of the N1/C2 bond and exchange of the alkylamino (arylamino) group 1 through the carbon atom of the methylene group 6. The aminodihydropyridinethiones11, which can be regarded as cyclic derivatives of 3-aminothiocrotonamide, react with bistrichlorophenylmalonate under diacylation, and with formaldehyde and primary amines to yield aminodialkylation products of the enamine system, tetrahydro-4-hydroxy-7,7-dimethyl-5-thioxopyrido[4,3-b]pyridine-2(1H)-ones13, 14 and hexahydro-7,7-dimethylpyrido[4,3-d]pyrimidine-5(6H)-thiones18, 19, 21 respectively. H2O2 converts11 to the corresponding 4-aminodihydro-2(1H)-pyridones22, which can be reconverted into11 with P4S10.11 reacts with alkyl halides to 2-alkylthiodihydropyridines23, 24, 25. The mechanism of the methylpyrimidine-pyridine rearrangement is discussed.  相似文献   

18.
By employing an unprecedented tri-triazole ligand, 4-amino-3,5-bis-(1H-1,2,4-triazole)-1,2,4-triazole (H2L), two Zn(II)/Cd(II) metal-organic frameworks (MOFs), [ZnL]·3H2O (1) and [CdL]·H2O (2), were successfully synthesized and characterized. In the two complexes, M(II) centers are chelated and bridged by L bridges to form a one-dimensional (1-D) 41 helical chain in 1 with high-symmetry Pbca, and a 21 helical chain in 2 with lower symmetry P21/n, respectively. The two chains are further linked by L into two structure-correlated three-dimensional (3-D) architectures. PXRD and TG analysis confirmed the phase purity and stability of 1 and 2. The solid-state fluorescence properties of the prepared MOF revealed a maximum emission at 382?nm and 393?nm (λex = 330?nm), ascribing to the intra-ligand transitions. Interestingly, an additional strong emission peak at 516?nm can be observed in 1 (below 400?°C), while the emission was silenced in 2. The additional emission band may be attributed to the subtle difference of architectural features and coordination configurations between in 1 and 2.  相似文献   

19.
Via an oxidation reaction of Cu(I) iodide with pyridine-2,6-dicarboxylic acid (H2L) in DMF three copper(II) complexes, [(CH3)2NH2]2[CuL2] (1), K2[CuL2]?H2L?H2O (2) and [Cu(L)(H2O)]n (3), were synthesized and characterized. The structures of 1–3 were determined by single crystal X-ray diffraction studies. In-situ DMF decomposition produces dimethylamine base under solvothermal conditions and a proton transfer reaction takes place for the complex formation of 1. 3-D networks are stabilized in 1 and 2 via hydrogen bonds. Complex 3 is a 1-D coordination polymer with Cu-O semi-coordination bonds. Thermal decomposition of the complexes results in the corresponding metal oxides. Also, the electrochemical behavior of 1 was determined to be a metal-centered and diffusion-controlled, one-electron reduction process.  相似文献   

20.
Two transition metal (Zn, Cu) complexes with a Schiff base (salicylideneglycine) and 1,10-phenanthroline: (C9H7NO3)Zn(C12H8N2)(H2O) (1) and (C9H7NO3)Cu(C12H8N2) (2) have been synthesized and characterized, including crystal structures, spectral characterization, thermogravimetric analyses and quantum chemistry calculations. X-ray crystallographic analysis shows the zinc to be six-coordinate mode, forming a slightly distorted octahedral geometry. The structure of 2 can be evaluated by the Addison distortion index (τ = 0.17), which indicates that the coordination environment of Cu is distorted slightly from square pyramidal (SP). The superoxide dismutase mimetic activity of the complexes was investigated by NBT-illumination. Complex 2 (IC50 = 6.15 µM) has better SOD–like activity than 1 (IC50 = 0.79 µM), although the SOD-like activity for 2 is not higher than some reported, it shows the possibility of SOD-like activity for the complexes with this amino-Schiff-base ligand (salicylideneglycine).  相似文献   

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