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1.
Abstract

The photochemical, thermo-catalytical and thermal reactions of diazoalkanes with dialkyl (thio)phosphites were studied.

Thus, the photolysis of dimethyldiazomalonate and methyl-diazoacetate with dialkyl(thio)phosphites gives P-H insertion products only upon triplet-sensitized conditions (i), whereas diphenyldiazomethane gives P-H insertion products upon direct photolysis as well (ii). The investigation of 31 the reaction mechanism is based on CIDNP 31P method. The catalytical reactions (iii) are a convenient method of preparing (thio)phosphonates.  相似文献   

2.
Mixed Dicyanamido (thio) cyanato-cobaltates(II) Preparation and properties of mixed anionic pseudohalide-complexes of cobalt(II) [CoX2Y2]2? and [CoX3Y]2? (X = NCS, NCO, Y = N(CN)2) are reported. The structures of the complexes are discussed using the results of infrared and electronic spectroscopy and of magnetic measurements.  相似文献   

3.
The reaction of the potassium salt of the N-(thio)phosphorylated thioureas AdNHC(S)NHP(O)(OiPr)2 (HLI , Ad = Adamantyl) and MeNHC(S)NHP(S)(OiPr)2 (HLII ) with Co(II) and Zn(II) in aqueous EtOH leads to [MLI,II 2] chelate complexes. They were investigated by UV-vis, 1H and 31P NMR spectroscopy, and microanalysis. The molecular structures of [MLI 2] were elucidated by single crystal X-ray diffraction analysis. The metal centers in both complexes are found to be in a distorted-tetrahedral O2S2 environment formed by the C=S sulfur atoms and the P=O oxygen atoms of two deprotonated LI ligands. The photoluminescence properties of [ZnLII 2] are also reported.  相似文献   

4.
Abstract

The analysis of all known synthesis methods of N-(thio)phosphorylthiómides of the common formula RC(S)NHP(X)R'2 (1), where R=Alk, Ar; R'=óIk, ór, SAIk, SAr. Alk, Ar; X=O,S has been gave in this report. We worked out the simple and convenient syntheses methods of this class compounds.  相似文献   

5.
Abstract

A new and straightforward procedure has been developed for the preparation of symmetrical and unsymmetrical 6-(N-alkyl(aryl)amino)- and 6-(N,N-bisalkyl(aryl)amino)-2,4-bis(alkyl(aryl)thio)pyrimidines. The two identical or different alkylthio groups were successfully introduced into the pyrimidine ring of 4-amino-6-hydroxy-2- mercaptopyrimidine via S-alkylation with alkyl halides, and via a nucleophilic displacement with sodium alkylmercaptides, affording the key intermediate symmetrical and unsymmetrical 2,4-bis(alkyl(aryl)thio)-6-aminopyrimidines. Subsequently, N-alkylation of the 2,4-bis(alkyl(aryl)thio)-6-aminopyrimidines with alkyl halides conveniently gave the desired products. The human anti-platelet activities of all the synthesized new compounds were also evaluated.

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   

6.
The Diels–Alder cycloaddition of anthracene and nitrostyrene catalyzed by the squaramide‐derived aminocatalysts ( Sq ) recently reported by Jørgensen and co‐workers (Angew. Chem.­ 2012 , 124, 10 417; Angew. Chem. Int. Ed.­ 2012 , 51, 10 271) has been studied by using modern tools of computational quantum chemistry. This catalyst is compared with analogous urea‐, thiourea‐, and thiosquaramide‐derived aminocatalysts. Ultimately, a thiosquar‐amide‐derived catalyst is predicted to result in the lowest free‐energy barrier, while retaining the same high degree of enantioselectivity as Sq . This stems in part from the superior hydrogen‐bonding ability of thiosquaramides, compared to squaramides and (thio)ureas. We also examine the hydrogen‐bonding ability of (thio)ureas and (thio)‐squaramides in model complexes. In contrast to previous work, we show that aromaticity does not contribute significantly to the enhanced hydrogen‐bonding interactions of squaramides. Overall, thiosquaramide, which has not been explored in the context of either organocatalysis or molecular recognition, is predicted to lead to strong, co‐planar hydrogen bonds, and should serve as a potent hydrogen‐bonding element in a myriad of applications.  相似文献   

7.
制备了4-苯基-1-(吡啶-2-亚甲基)氨基脲(PPMSC)和4-苯基-1-(吡啶-2-亚甲基)氨基硫脲(PPMTC).用元素分析、MS、1HNMR、UV吸收光谱、X射线单晶衍射和固体CD光谱等对其进行了表征.晶体结构数据显示PPMSC属于Sohncke P212121空间群,单个分子之间通过氢键形成一个一维螺旋链状结构,沿a轴形成左手螺旋结构.固体CD光谱和重结晶实验证明,PPMSC手性晶体的形成是结晶诱导的绝对不对称合成.PPMTC的固体CD光谱和重结晶实验具有与PPMSC类似现象.  相似文献   

8.
The ring-opening difluoromethylation-halogenation of cyclic (thio)ethers is reported through a simple strategy relying on carbon-chalcogen bond activation with difluorocarbene. The reaction proceeds through in situ protonation of the previously little-known difluoromethylene oxonium or sulfonium ylide intermediate followed by ring-opening with halide ion to afford halogenated acyclic difluoromethyl (thio)ethers that can then be employed for further elaboration. TMSCF2X (X=Br, Cl) are unique reagents to achieve this synthetic purpose, which serve as both the difluorocarbene source and the halide ion source.  相似文献   

9.
The electrochemical behavior of crown-containing N-(thio)phosphoryl(thio)ureas and their complexes with 3d transition metals was studied by dc voltammetry on a graphite electrode in acetone. Crown-containing N-(thio)phosphoryl(thio)ureas are not reduced but are oxidized on solid electrodes in the examined range of potentials; the electrons are transferred via the (thio)urea group. Electrooxidation of macrocyclic Co(II), Ni(II), and Cu(II) complexes probably occurs via formation of M(III) complex species. Electroreduction of these metal complexes involves stepwise electron transfer, with the oxidation state of the metal atom decreasing to 0, followed by dissociation of the electrochemical reaction products.  相似文献   

10.
Abstract

The new 1,1-disubstituted 3-diphenoxy(thio)phosphoryl-(thio)ureas, R1R2NC(X)NHP(0Ph)2, HA, with X,Y = O,S, were synthesized by addition of secondary mines to the corresponding P-iso(thio)cyanates. This reaction is reversible if X,Y = S. (PhO)2P(Y)Cl reacts with H2NC(X)NR2 in the presence of an HCl acceptor only if X,Y a 0. Side reactions are observed. Phosphorylated derivatives of biuret were isolated from such a reaction mixture.  相似文献   

11.
Two new (NS)2 Schiff bases, (4-NO2Ph)2dapte (N,N′-di-(4-nitrobenzaldimine)-1,2-di(o-aminophenylthio)ethane) (1) and (thio)2daptx (N,N′-di-(thiophenedimine)-1,4-di(o-aminophenylthio)xylene) (2), and their 1-D copper(I) coordination polymers [Cu2(μ-Br)2(μ-(4-NO2Ph)2dapte)] n (3), [Cu2(μ-I)2(μ-(4-NO2Ph)2dapte)] n (4), and [Cu2(μ-I)2(μ-(thio)2daptx)] n (5) have been synthesized and characterized by elemental analyses and IR, UV-Vis, and 1H NMR spectroscopy. The structures of 4 and 5 have been determined by X-ray crystallography and were shown to consist of Cu2(μ-I)2 secondary building units (SBUs) bridged by (4-NO2Ph)2dapte or (thio)2daptx ligands. The CuNSI2 coordination sphere is a distorted tetrahedral in both cases. Both (4-NO2Ph)2dapte and (thio)2daptx are N2S2-bis-bidentate chelating ligands with the two imine nitrogens and two thioether sulfurs in a trans configuration generating dinuclear [Cu2(μ-(4-NO2Ph)2dapte)] and [Cu2(μ-(thio)2daptx)]. These units are connected by two bridging iodides to form 1-D copper(I) coordination polymers. The electrochemical properties of 35 are also reported and discussed.  相似文献   

12.
Abstract

A series of novel oligodentate ligands has been designed by the modular assembly of ortho-(thio)phosphorylated anilines with a range of commercially available carbonyl compounds. The new ligands readily form complexes with a series of metal ions (Pd(II), Cu(II), Ni(II), and Re(I)) both in neutral and deprotonated forms, providing OO, SN, ONO, SNO, SNS, SNN, and ONN donor sets. The structure and composition of the resulting complexes depend on the nature and mutual disposition of the donating groups as well as on the reaction conditions.  相似文献   

13.
《Analytical letters》2012,45(7-8):747-753
Abstract

Dissociation constants pKa1 and pKa2 of 4- (2-pyridylazoresorcinol) were determined spectrophotometrically in the presence of CPB and CPTB. The effect of a strong electrolyte, NaCl, was studied.  相似文献   

14.
Two new thio/selenidogermanates [Ni2(μ‐teta)(teta)2]Ge4S10·H2O ( 1 ) and [Ni(teta)2]2Ge4Se10·0.5H2O ( 2 ) (teta = triethylenetetramine) were solvothermally synthesized and structurally characterized. Both 1 and 2 consist of discrete [Ge4Q10]4– (Q = S, Se) adamantane‐like anions with complex cations as counterions. The [Ge4Q10]4– (Q = S, Se) anions are composed of four nearly tetrahedral GeIV atoms to which are bonded four terminal Q atoms and six bridging Q atoms. Although numerous thio/selenidogermanates with complex cations have been reported, their anions are usually dimeric [Ge2Q6]4– (Q = S, Se) species. 1 and 2 represent the rare examples of the adamantane‐like thio/selenidogermanates with complex cations. The optical absorption spectra indicate that 1 and 2 are wide‐band‐gap semiconductors.  相似文献   

15.

A facile and rapid synthesis of thio compounds, analogues to ciprofloxacin, and norfloxacin is described.  相似文献   

16.
2-Nitrodiene compound 1 was stirred with p-fluorothiophenol for a long time and compound 3 was obtained. Compound 1 gave bis(thio)substituted 2-nitrodiene compound 4 and tris(thio)substituted compound 5 with 2 moles of p-fluorothiophenol in the presence of NaOH in ethanol. The compounds 9a–g have been prepared from 8a–g and 3. Compound 7 was obtained from the reaction of mono(thio)substituted 2-nitrodiene with morpholine. Compound 3 gives 11a–d in the reaction with piperidines in CH2Cl2 (or ether). Compound 13a–b have been obtained from the reaction of compound 3 with primary amines 12a–b. Compound 3 gives 15 and 16 in the reaction with 2,5-dimethylpiperazine in CH2Cl2.

  相似文献   

17.
Abstract

The preparation of 2-aryl-3,3-bis((perfluoroalkyl)thio)acrylonitriles is described. The electrogenerated cyanomethyl base/anion obtained from electroreduction of acetonitrile promotes reactions between arylacetonitrile, carbon disulfide, and perfluoroalkyl iodides. The new fluorinated acrylonitriles were obtained in good yields under mild reaction conditions.  相似文献   

18.
《Electroanalysis》2002,14(24):1728-1732
An electrochemical study related to the electrooxidation of 4‐amino‐3‐thio‐5‐methyl‐1,2,4‐triazole (I), 4‐amino‐3‐thio‐5‐phenyl‐1,2,4‐triazole (II) and 3‐thio‐5‐phenyl‐1,2,4‐triazole (III), in 10% v/v methanol‐acetate buffer pH 4.6 has been performed. A variety of electrochemical techniques such as differential pulse voltammetry, cyclic voltammetry, double‐potential step chronoamperometry, rotating‐disk electrode voltammetry and coulometry, were employed to clarify that the mechanism of the electrode process follows the oxidation of thiol compounds. All the compounds exhibit similar redox behavior under the given conditions. They display one irreversible oxidation peak, which is diffusion controlled. From the plot of current function in cyclic voltammetry and the ratio of ic/ia less than one in double‐potential step chronoamperometry, it was established that these compounds undergo an one electron oxidation followed by a dimerization process involving the formation of disulfide derivative (EC mechanism). The pKa values were obtained by the dependence of limiting current and potential with in the wide pH interval. The transfer coefficients, the diffusion coefficients and rate constant of coupled chemical reaction were also reported. The substituent effects were also investigated.  相似文献   

19.
Abstract

Among the new compounds of N-(thio)phosphorylthiómides. the copper(II) complex with N-diisopropoxyphosphorylthiohenzamide (Cul. 2) exhibits series of unusual properties which have been extcnsively investigated in the present work. The X-ray structure of CuL2 has been determined Crystals of CuL2 are monoclinic. P21/c, a = 15.610, b = 11.880, and c = 18.320 Å, β = 106.74°. Z = 4. The CuL2 complex has the cis-structure with Cu-S distances ranging from 2.238 to 2.253 Å and Cu-O distances being from 1.919 to 1.937 Å (Figure).  相似文献   

20.
Abstract

Five new complexes ZnL2(ClO4)2 (1), CdL2(ClO4)2 (2), CdL2(BF4)2 (3), CdLCl2 (4), and CdL(NO3)2 (5) [L = ((Me2N)2PSe)2NMe] have been synthesized and characterized by elemental analysis, infrared (IR) and multinuclear (31P, 77Se, and 113Cd), and nuclear magnetic resonance (NMR) spectroscopy. The 31P and 77Se NMR data showed that the title ligand is coordinated in a bidentate fashion to the metal center via its both P=Se groups. The solution structure of the cadmium complexes was further confirmed by its 113Cd NMR spectra, which displayed a quintuplet for the perchlorate complex and a triplet for each of the nitrate and chloride complexes, respectively due to coupling with four (two ligands) and two (one ligand) equivalent phosphorus nuclei, consistent with a four-coordinate tetrahedral geometry for the cadmium center. The results are discussed and compared with the corresponding oxo and thio analogues.  相似文献   

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