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New hyperbranched polymers have been synthesized through the 1,3-dipolar polycycloaddition of the AB2 monomer—2-azido-4,6-bis(propynyloxy)-[1,3,5]-triazine. The polymers contain conjugated heteroaromatic triazine and triazole cycles and terminal acetylene groups. The products have been characterized by exclusion liquid chromatography and IR and 1H NMR studies.  相似文献   

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Reaction of 2-methylthio-thieno[2.3-d]pyrimidin-4(3H)-ones with heterocyclic secondary amines, ethanolamine and hydrazine, resp., gave the corresponding derivatives with a basic substituent in position 2. Cyclization of the hydrazino compounds with formic acid gave derivatives of thieno[2.3-d]-1.2.4-triazolo[4.3-a]pyrimidine and [1]benzothieno[2.3-d]-1.2.4-triazolo[4.3-a]pyrimidine, two new heterocyclic systems.  相似文献   

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Trovacene Chemistry. 13 [1] On Being Lead and Mislead in the Synthesis of Di([5]trovacenyl)ketone Di([5]trovacenyl)ketone ( 3¨ ) has been prepared from lithio‐[5]trovacene and dimethylcarbamoyl chloride and studied by X‐ray diffraction, cyclic voltammetry, magnetic susceptometry and EPR spectroscopy. Slight variation of the synthetic protocol affords an unusual trinuclear complex 5 ? that is also fully characterized. Spin‐spin exchange interaction is smaller in 3¨ than in 1,1‐di([5]trovacenylethene ( 2¨ ), which differs from 3¨ by a replacement of O for CH2. The novel trinuclear complex 5 ? , however, displays exchange coupling very similar to that observed in 1‐methoxy‐2,5,6‐tri([5]trovacenyl)benzene ( 7 ? ). In both cases, an unsymmetrical triangular arrangement of S = 1/2 centers is encountered. These findings are discussed in terms of the nature of the respective spacers.  相似文献   

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The title compound is functionalized by a series of reactions to yield derivatives in the forms of hydroxides, ketones, ketals, lactones, etc. Their structures are analyzed by NMR spectroscopy.  相似文献   

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We report the measurement of 113Cd NMR chemical shift data for homoleptic thioether and related aza and mixed aza/thiacrown complexes. In a series of Cd(II) complexes containing trithioether to hexathioether ligands, we observe solution 113Cd NMR chemical shifts in the range of 225 to 731 ppm. Upfield chemical shifts in these NMR spectra are seen whenever: (a) the number of thioether sulfur donors in the complex is decreased, (b) a thioether sulfur donor is replaced by a secondary nitrogen donor, or (c) the size of the macrocycle ring increases without a change in the nature or number of the donor atoms. Changes in the identity of non-coordinating anions such as perchlorate or hexafluorophosphate have little effect upon the 113Cd NMR chemical shift in solution. We report the X-ray structure of the complex [Cd([12]aneS4)2](ClO4)2 ([12]aneS4 = 1,4,7,10-tetrathiacyclododecane) (1) which shows the first example of octakis(thioether) coordination of a metal ion, forming an unusual eight-coordinate square antiprismatic structure. We report the X-ray structure of the complex [Cd([9]aneS3)2](PF6)2 ([9]aneS3 = 1,4,7-trithiacyclononane) (3a) which shows hexakis(thioether) coordination to form a distorted octahedral structure. We have also prepared and characterized the Cd(II) complex of a mixed azathiacrown, [Cd([18]aneS4N2)](PF6)2 ([18]aneS4N2 = 1,4,10,13-tetrathia-7,16-diazacyclooctadecane) (6). Its X-ray structure shows a distorted octahedral S4N2 environment around the Cd(II) with the ligand coordinated in the rac fashion. We observe a solvent- and temperature-dependent 14N-1H coupling in the 1H NMR spectrum of the complex which is not present in analogous complexes with this ligand.  相似文献   

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Adamantylammonium (ADNH3+) was complexed with [18]crown-6, forming a supramolecular cation of (ADNH3+)([18]crown6), which was introduced into a [Ni(dmit)2]- salt as a supramolecular rotor. The cation layers were alternately arranged with [Ni(dmit)2]- layers in the crystal, in which the molecular rotation of (ADNH3+)([18]crown-6) was confirmed from the temperature-dependent solid-state 1H NMR.  相似文献   

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From the study of the hypothetical series Pb[PbInc–2pSbc]O6+p (O ? p < 1; 0 ? c < 2), the existence of the cubic pyrochlore Pb2II[In0.5Sb1.5]O6.5 has been established. This compound was obtained as an orange yellow powder, S.G. Fd4 m (No. 227), Z = 8, a = 10.5892(1) Å, V = 1187.38(3) Å3, Dc = 8.48 M gm?3. For Pb in 16(c) positions, In and Sb (1:3) randomly distributed in 16(d), oxygen atoms in 48(f) and in a half of the 8(a) sites, and oxygen positional parameter x = 0.429 (origin at center, 3 m), R = 0.062. The apparent interatomic distances (Å) are determined: Pb? O = 2.612; (In, Sb)? O = 2.019.  相似文献   

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