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1.
Bis(N,N‐di­methyl­thio­carbamoyl­thio)­acetic acid, [(CH3)2NC(=S)S]2CHC(=O)OH or C8H14N2O2S4, exists as a centrosymmetric hydrogen‐bonded dimer [O?O 2.661 (3) Å].  相似文献   

2.
Bo Zhang  Silong Xu 《Tetrahedron》2008,64(40):9471-9479
In this report, the dipolarophile imines with easily removable activating group O,O-diethyl(thio)phosphoryl have been investigated in the nucleophilic phosphine-catalyzed [3+2] cycloaddition reaction of electron-deficient allenes. Under the catalysis of a tertiary phosphine, N-(thio)phosphorylimines readily undergo the [3+2] cycloaddition reaction with ethyl 2,3-butadienoate or ethyl 2,3-pentadienoate, affording the corresponding N-(thio)phosphoryl 3-pyrrolines in moderate to high yields with good diastereoselectivity. Removal of the (thio)phosphoryl group from the adducts has been successfully achieved via the acidic methanolysis of the P-N bond, giving the free amine 3-pyrrolines in fair to good yields without severe aromatization. Thus, a facile synthesis of N-unsubstituted 3-pyrrolines is established from the phosphine-catalyzed [3+2] cycloaddition reaction of allenes with imines.  相似文献   

3.
(+)-Poly[thio 1-(N-sec-butyl-N-methylaminomethyl) ethylene] (I) and (-)-poly[thio 1-(N-methyl-N-(1-phenylethyl)aminomethyl) ethylene] (II) are soluble in methanol or in a 10/90 dioxane-methanol mixture in the presence of CuCl2. This salting-in effect results from interactions between macromolecules and this salt. With a large excess of salt (molar ratio > 8) a precipitate is obtained whose composition is close to a CuCl2:monomer unit ratio of unity. Ultraviolet, optical rotatory dispersion (ORD) and circular dichroism (CD) spectra in solution are described. The three extrinsic Cotton effects observed between 300 and 800 nm are assigned to charge transfer and d-d electronic transitions of Cu(II) complexed with the macromolecules. In the same solvent system, Cu(II) shows similar induced optical activity in the presence of a nonaminated homolog, (+)-poly(propylene sulfide) taken as a model of the chains of I and II. No extrinsic Cotton effects are observed in the presence of an optically active tertiary amine without the thioether sulfur atom, (+)-N-sec-butyl-N-methyl-N-(oxirane-2-ylmethyl)amine. It is concluded that Cu(II) gives rise to charge-transfer complexes with sulfur atoms, while tertiary amine groups are probably protonated in this particular medium.  相似文献   

4.
Thermal and Photochemical Properties of Chloro Copper (II) Complexes in Acetonitrile. I. In the systems CuCl2? AN spontaneous redox changes take place. Acetonitrile as a ligand with π-acceptor properties causes a mutual interaction of ligands in the coordination sphere; the CuII gets reduced to CuI while the chloro ligand is oxidized. Probably the system σ (Cu→N) and π (Cu→N) is formed. Spectrophotometrically has been found that the concentration of [CuCl3(AN)]-ions, which above all undergo redox reactions, as also that of the ions [CuCl(AN)3]+ increase with increasing temperature while the concentration of CuCl2(AN)2 decreases. The relationship between the composition of the coordination sphere and the redox properties of chloro copper(II) complexes in acetonitrile was proved.  相似文献   

5.
A new tripeptide (dimer), bis[(L -cysteine-S-acetyl)-L -hemicystinyl(S2S2)-D -valine] ( 6 ) was synthesized by coupling N-(tert-butoxycarbonyl)-S-carboxymethyl-L -cysteine benzyl ester ( 1 ) with S-trityl-L -cysteinyl-D -valine benzyl ester and subsequent removal of the protecting groups. After reduction of the disulfide, the free tripeptide Cys (CH2CO-Cys-D -Val) ( Ib ) was used as a substrate of isopenicillin-N synthetase in a cell-free conversion to 6-[2-((D -2-amino-2-carboxyethyl)thio)acetamido]penicillanic acid ( IIa ).  相似文献   

6.
Semiempirical quantum-chemical calculations of the spatial arrangement and electronic structure of the tautomeric forms of N-[diisopropoxy(thio)phosphoryl](thio)benzamides were carried out by the PM3 method. The most energetically favorable forms were revealed, and the reasons for their stabilization were discussed.  相似文献   

7.
A new, highly efficient allylation reagent—lithium allyldibutylmagnesate (allylBu2MgLi)—was obtained by mixing allyl-magnesium chloride (1 equiv) and n-BuLi (2 equiv). N-Lithiated and N-methyl substituted 1H-pyridine-2-thiones and -ones were successfully and regioselectively allylated by treatment with allylBu2MgLi yielding 6-allyl-3,6-dihydro-1H-pyridine-2-(thio)ones and 4-allyl-3,4-di-hydro-1H-pyridine-2-(thio)ones. The latter were formed by a 3,3-sigmatropic Cope rearrangement of the former.  相似文献   

8.
The fragmentation pathways of 2-keto(thio)-6-methyl-5-carbethoxy(acetyl)-4-aryl-1,2,3,4-tetrahydropyrimidines were established using high resolution mass spectra and DADI spectra. An unusual rearrangement was observed, which involves cyclization of the aryl substituent in the 4 position with the oxygen of an ester group and elimination of a C2H5 radical.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 360–365, March, 1989.  相似文献   

9.
Zusammenfassung Neue gravimetrische, oxydimetrische und spektrophotometrische Methoden für die Bestimmung kleiner Wismutmengen (1–15 mg/ 25 ml) als [Bi(Thio)4] [Cr(NCS)4(Amin)2]3 (Thio=Thioharnstoff; Amin=Anilin bzw. Morpholin) wurden beschrieben und die Resultate statistisch verarbeitet.
Thiocyanato-chromium(III) complexes in chemical analysis
Summary New gravimetric, oxidimetric and spectrophotometric methods for determining small amounts of bismuth (1–15 mg Bi/25 ml test solution) as [Bi(thio)4][Cr(NCS)4(amine)2]3 (thio=thiourea; amine=aniline, morpholine) are described and the results analysed statistically.
  相似文献   

10.
Turquoise crystals of the title salt, propyl­ammonium di‐μ‐thio‐1:2κ4S‐di­thio‐2κ2S‐tris(2‐amino­ethyl)­amine‐1κ4N‐anti­mony(V)­nickel(II), (C3H10N)[NiSbS4(C6H18N4)] or [PAH][Ni(tren)SbS4] [where tren is tris(2‐amino­ethyl)­amine and PA is propyl­amine], were synthesized under solvothermal conditions by reacting [Ni(tren)2]Cl2, Sb and S in a solution of PA. The NiII ion is octahedrally surrounded by four N atoms of the tetradentate tren mol­ecule and by two S atoms of the tetrahedral [SbVS4]3? anion, thus forming the anionic [Ni(tren)SbS4]? part of the compound. Charge balance is achieved through the PAH+ cation. An extended intermolecular hydrogen‐bonding network is observed between the anion and the cation.  相似文献   

11.
The reaction of tetrachloro-phenylimido-tungsten(VI) [W(NPh)Cl4] with tert.-butyltrimethylsilylamine [tert. Bu(Me3Si)NH] gave the dimeric complex [W(NBu-tert.)(μ2-NPh)Cl2 (tert.-BuNH2)]2 which was shown by X-ray crystallography to contain bridging phenylimido and non-bridging (nearly linear) tertiary butylimido groups together with tertiary butylamine ligands coodinated to octahedral tungsten. The tert.-buty1amine NH2 protons were non-equivalent due to NH…Cl bridging within the dimer.  相似文献   

12.
The reaction of 5-chloro-2-nitrobenzonitrile with a variety of mercaptoheterocycles provided the corresponding 2-nitro-5-[(heterocyclic)thio]benzonitriles. Reduction to the amine followed by cyclization with chloroformamidine hydrochloride afforded a series of 2,4-diamino-6-[(hetero-cyclic)thio]quinazolines. Bromination, oxidation, and amidine formation were accomplished with 2,4-diamino-6-[(4-phenyl-2-thiazolyl)thio]quinazoline (23) to provide additional analogs. Several of these compounds exhibited suppressive antimalarial activity against drug-sensitive lines of Plasmodium berghei in mice.  相似文献   

13.
In the cationic complex present in the title compound, chloro­[2‐(4‐imidazolyl‐κN1)­ethyl­amine‐κN](1,10‐phenanthroline‐κ2N,N′)copper(II) chloride monohydrate, [CuCl(C5H9­N3)­(C12H8N2)]Cl·H2O, the metal centre adopts a five‐coordinate geometry, ligated by the two phenanthroline N atoms, two amine N atoms of the hist­amine ligand (one aliphatic and one from the imidazole ring) and a chloro ligand. The geometry around the Cu atom is a distorted compressed trigonal bipyramid, with one phenanthroline N and one imidazole N atom in the axial positions, and the other phenanthroline N atom, the histamine amine N atom and the chloro ligand in the equatorial positions. The structure includes an uncoordinated water mol­ecule, and a Cl ion to complete the charge. The water mol­ecule is hydrogen bonded to both Cl ions (coordinated and uncoordinated), and exhibits a close Cu⋯H contact in the equatorial plane of the bipyramid.  相似文献   

14.
N-Phenylamide and phenyl (thio)esters of 3-phenylpropiolic acid add benzene in the presence of CF3SO3H or AlX3 (X = Cl, Br) to give 4,4-diphenyl-3,4-dihydroquinolin-2-one, 4,4-diphenyl-3,4-dihydrocoumarin, and 4,4-diphenyl-3,4-dihydrothiocoumarin, respectively.  相似文献   

15.
Higher values of the energies of the highest occupied molecular orbitals for N-benzyl-4-[9-(thio)-xanthenyl]aniline, N-benzyl-4-(5-dibenzosuberenyl)aniline molecules and their zwitterions and the electron density increase on the reaction center (carbon atom in the CH2-group) for the latter were obtained in the quantum-chemical calculations by RHF/6-31G(d) method. This explains the possibility and the ease of dehydrogenation of N-benzyl-4-[9-(thio)xanthenyl]aniline with imines in trifluoroacetic acid due to effect of the substituents. The calculated data suggest the same possibility for N-benzyl-4-(5-dibenzosuberenyl)aniline: it is dehydrogenated already in the synthesis from N-benzylaniline and dibenzosuberenol in acetic acid.  相似文献   

16.
Ultra-violet, ORD and CD spectra of (?)poly[thio1-(N-N-diethylaminomethyl) ethylene] (Ia) prepared by stereoelective polymerization of racemic N-N-diethyl-N-(thiirane-2-ylmethyl) amine using ZnEt2-(—) 3-3-dimethyl-1,2 butanediol as initiator system, of (+)poly[thio1-(N-N-diethyl aminomethyl) ethylene] obtained from a partially resolved enantiomer using ZnEt2-CH3OH as initiator system, of poly[thio1-(N-methyl-N-sec-butyl aminomethyl) ethylene] and of poly[thio1-(N-methyl-N-(1-phenylethyl) aminomethyl) ethylene] in organic solvents (tertiary amine form) and in water (hydrochloride form) are described. Observed Cotton effects are associated with electronic transitions of chromophores by comparison with model molecules: N-methyl2-aminobutane, ethyl-thio-2-methylbutane and polypropylene sulfide. For polyamine (Ia), their contributions to optical rotatory powers in the visible are evaluated after decomposition of corresponding CD curves in Gaussian partial Cotton effects. The effects of other optically active electronic transitions located below 180 nm are deduced by difference. Influence of positions of chromophores with regard to chiral centers and of the protonation of nitrogen atoms on observed Cotton effects are discussed.  相似文献   

17.
The X‐ray structure of 2‐Chloro‐1, 3‐diisopropyl‐4, 5‐dimethylimidazolium dichlorophosphate ( 2 ) (obtained from 2‐chloro‐1, 3‐diisopropyl‐4, 5‐dimethylimidazolium chloride 1 and POCl3 in the presence of water) is reported.  相似文献   

18.
4‐Chloro‐5‐(2‐phenoxyethoxy)phthalonitrile, C16H11ClN2O2, (I), and 4‐chloro‐5‐[2‐(pentafluorophenoxy)ethoxy]phthalonitrile, C16H6ClF5N2O2, (II), show different types of electrostatic interaction. In (I), the phenoxy and phthalonitrile (benzene‐1,2‐dicarbonitrile) moieties are well separated in an open conformation and intermolecular C—H...π interactions are observed in the crystal packing. On the other hand, in (II), the pentafluorophenoxy moiety interacts closely with the Cl atom to form a folded conformation containing an intramolecular halogen–π interaction.  相似文献   

19.
以取代或未取代苯并(硫)吡喃-4-酮(1a1c)为原料, 分别与呋喃甲醛和6-氨基胡椒醛发生缩合反应合成了一系列的取代或未取代苯并(硫)吡喃衍生物2a2c3a3c, 化合物2a2c3a3c的结构经IR, 1H NMR, MS和元素分析进行鉴定和表征.  相似文献   

20.
The title compound, [(S)‐2‐(anilino­methyl)­pyrrolidine‐N,N′]‐chloro(η6para‐cymene)­ruthenium(II) chloride, [RuCl‐(C10H14)(C11H16N2)]Cl, has been synthesized by the reaction of [RuCl2(p‐cymene)]2 (p‐cymene is para‐iso­propyl­toluene) with (S)‐2‐(anilinomethyl)­pyrrolidine in triethyl­amine/2‐propanol. The Ru atom is in a pseudo‐tetrahedral environment coordinated by a chloride ligand, the aromatic hydro­carbon is linked in a η6 manner and the amine is linked via its two N atoms. The chloride anion is involved in hydrogen bonding with the di­amine moieties through N—H?Cl interactions, with N?Cl distances of 3.273 (4) and 3.352 (4) Å.  相似文献   

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