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1.
Oligomers and polymers of the general types [RR′P(O)OA1F2]n, I, and [F2AlOP(R)(O)OAlF2]n, II, were prepared by the addition of phosphonic or phosphinic acids and hydrogen fluoride to etherated alanes. The hydrocarbon moieties (R,R′) on the phosphonic and phosphinic acids were important determinants of physical and chemical properties. When the alkyl moieties contained six or more carbon atoms type I oligomers were partially crystalline, soluble in tetrahydrofuran, and fused below 415°C. Type II polymers were soluble in tetrahydrofuran when n-octyl or larger alkyl moieties were used, but these polymers tended to be amorphous and liberated solvated tetrahydrofuran below 225°C. Data are presented in support of inter-monomer fluorine bridge bonding; that is, Al? F? Al bonds.  相似文献   

2.
A series of coordination polymers, poly[bis(phosphinatoalanyl)phosphonates], [X(Y)AlOP(R)(O)OAl(Y′)(X′)]n, were synthesized in which the terminal alanyl substituents (X,Y,X,′Y′) consisted of phosphinato (OPRR′O) or fluoro (F) moieties. The properties of the polymers were primarily dependent upon the type of terminal substituent and the hydrocarbon moieties (R,R′) on phosphorus. Polymers with four phosphinato moieties gave molecular weights M?n to 120000 with intrinsic viscosities [η] from 1.5 to 18; the corresponding solids were partially crystalline, melted before decomposition, and were film-forming when larger phosphorus substituents were incorporated. Sequential replacement of the phosphinato moieties with fluorine resulted in molecular weights below 10000 and low viscosities. The properties of the polymers are examined, and the roles of substituents on probable structures are discussed.  相似文献   

3.
A new class of coordination polymers, polybis(phosphinato)fluoroalanes, [Al(F) (OPRR′O)2n], where R,R′ are alkyl, phenyl, or benzyl, was prepared and studied. The properties of these polymers are influenced by the phosphinate (R) substituents; polymers having n-alkyl groups with more than five carbons are flexible and exhibit unusual hydrolytic stability. A polymer was obtained with a degree of polymerization of 104 by incorporating a 2:1 ratio of benzyl(n-heptyl) and di-n-octyl phosphinate groups. The properties of the flexible materials are consistent with linear rather than highly crosslinked or network systems. Feasible structures are proposed for the polymers.  相似文献   

4.
Dependencies of various physicochemical constants of organic compounds (A) versus number of carbon atoms in the molecule within different homologous series [Af(n C )] usually are non-linear. The simplest recurrent equation A(n + 1) = a A(n) + b, connecting A-values for homologues (n + 1 carbon atoms) with the values of the same constants for previous members of series (n carbon atoms), indicates practically “ideal” linear character for most properties of organic compounds. It is the reasonable basis for approximation (or extrapolation) any physicochemical constants within any homologous series using the standard approach without special selection of appropriate algebraic functions. Principal mathematical properties of the function A(n + 1) = aA(n) + b and some of its chemical applications are considered.  相似文献   

5.
Cadmium acetate reacts with sulfamethoxazole (5‐methyl‐3‐isoxazolyl sulfanilamide) and with DMF / DMSO / pyridine to give the crystalline polymers [Cd(sulfamethoxazolato)2(L2)]n {L = DMF ( 1 ), DMSO ( 2 )} and [Cd(sulfamethoxazolato)2(Py)2]n·n(Py) ( 3 ). Complexes 1 , 2 and 3 confirm the tectonic character of the [Cd(sulfamethoxazolato)2(L)2] moieties and the remarkable ability of the {Cd(sulfamethoxazolato)4} fragments to be non selectively stabilized by monodentate ligands. In the polymeric assemblies of the title complexes the cadmium(II) atoms are linked through sulfamethoxazolato anions which alternate in their coordination with the isoxazolic N‐atoms and the aromatic amino groups. The chains of vicinal rings build tunnels along the crystallographic c axis.  相似文献   

6.
Heating hydroxyaquochromium(III) bis(phosphinates) at temperatures up to 200°C under vacuum yields the corresponding anhydrous polymers [Cr(OH)(OPRR'O)2]x. The infrared and visible spectra and solution properties lead to the following conclusions. When R and R′ are phenyl groups, the hydroxyl groups appear to bridge between adjacent chromium atoms in the chain together with the phosphinate ligands to yield a linear, triple-bridged polymer. When at least one substituent on the phosphorus is an alkyl group, some of the hydroxyl groups crosslink between chains to yield less soluble polymers. Comparison of the properties of these new polymers with the parent polymers suggests that the latter should be formulated [Cr(H2O)n(OH)(OPRR′O)2]x·pH2O and that they contain more than one kind of monomer unit. The parent polymers can be readily prepared by a new method which involves reaction of a soluble chromium(III) salt with alkali metal phosphinates or of chromium(III) hydroxide with phosphinic acids in a water–tetrahydrofuran mixture.  相似文献   

7.
The straightforward self-assembly reaction of R3Sn+ and [Fe(CN)6]3? affords three-dimensional (3-D) coordination polymers [(n-Bu3Sn)2(R3Sn)Fe(CN)6] n , R = n-Bu(I) or Ph(II). The architecture of these coordination polymers is closely related to zeolite and acts as a host with wide internal cavities or channels capable of encapsulating voluminous organic compounds. Aniline derivatives acting as guest are encapsulated within the cavities of the 3-D-polymeric hosts I and II by tribochemical reaction producing host–guest supramolecular polymers. The structures and physical properties of these hosts and their host–guest systems were investigated by elemental analysis, X-ray powder diffraction, IR, UV-vis, EPR, and magnetic measurements. The morphology of these systems was examined by scanning electron microscopy (SEM). The interesting feature of these host–guest supramolecular polymers is the enhanced electrical conductivities over those of the 3-D-coordination polymeric hosts upon encapsulation of conductive polymers within their cavities.  相似文献   

8.
Three copper(II) coordination polymers [Cu(mbtz)2(NCS)2]n ( 1 ), [Cu(mbtz)2Cl2]n ( 2 ) and [Cu(mbtz)(btec)0.5]n ( 3 ) (mbtz=1,3‐bis(1,2,4‐triazol‐1‐ylmethyl)benzene, btec=1,2,4,5‐benzenetetracarboxylate) were synthesized. In 1 and 2 , two mbtz ligands are wrapped around each other and are held together by Cu(II) atoms to form one‐dimensional double chain. In 3 , each btec ligand connects four Cu(II) atoms through its four carboxylate groups, resulting in a planar two‐dimensional [Cu(btec)0.5]n network. The Cu(II) atoms are further coordinated mbtz ligands to fulfil their coordination geometry and construct new [Cu(btec)0.5(mbtz)]n network. 2 and 3 further form the three‐dimensional network through the π···π stacking interactions between the mbtz ligands. The thermal stabilities of 1 , 2 and 3 were measured.  相似文献   

9.
《Journal of Coordination Chemistry》2012,65(17-18):1591-1601
The reaction of ferrocenylacetylide compounds with Co2(CO)8 at room temperature affords four complexes bearing ferrocenyl units with approximately tetrahedral (μ-alkyne)dicobalt moieties [R–(C≡C) n –R′] [Co2(CO)6] n [R?=?C5H5FeC5H4-C(CH3)2-C5H4FeC5H4, R′?=?H, n?=?1, n′?=?1 (1); R?=?C5H5FeC5H4 [ferrocenyl (Fc)], R′?=?–CH=CHCl, n?=?1, n′?=?1 (2); R?=?Fc, R′?=?Fc, n?=?2, n′?=?1 (3), n′?=?2 (4)]. The compounds were characterized by elemental analysis, IR, 1H(13C) NMR, MS and single-crystal X-ray diffraction analysis. The X-ray analyses show that coordination of the carbon–carbon triple bond and the dicobalt unit result in the formation of a Co2C2 tetrahedral core, and the substituents on the acetylenic units show a distortion from linearity that reflects this coordination mode.  相似文献   

10.
Polytetramethyl-p-silphenylenesiloxane (I) and polymethylphenylsiloxane (II) were prepared and subsequently reacted with hexacarbonylchromium to generate their n6-Cr(CO)3 complexed analogs, III and IV, respectively. During the complexation reaction, completing decomposition to chromium salts took place. Furthermore a competing chain scission reaction took place resulting in lower molecular weights for the complexed polymers. Heating III and IV resulted in carbon monoxide evolution and the presence of n6-Cr(CO)3 moieties lowered the thermal stability of the polymers.  相似文献   

11.
The recent results of investigations involving the electrochemical formation of polymers containing fullerenes and studies of their properties and applications are critically reviewed. From a structural point of view, these polymers can be divided into four main categories including (1) polymers with fullerenes physically incorporated into the foreign polymeric network without forming covalent bonds, (2) fullerene homopolymers formed via [2+2] cycloaddition, (3) “pearl necklace” polymers with fullerenes mutually linked covalently to form polymer chains, and (4) “charm bracelet” polymers containing pendant fullerene substituents. The methods of electrochemical polymerization of these systems are described and assessed. The structural features and properties of the electrochemically prepared polymers and their chemically synthesized analogs are compared. Polymer films containing fullerenes are electroactive in the negative potential range due to electroreduction of the fullerene moieties. Related films made with fullerenes derivatized with electron-donating moieties as building blocks are electroactive in both the negative and positive potential range. These can be regarded as “double cables” as they exhibit both p- and n-doping properties. Fullerene-based polymers may find numerous applications. For instance, they can be used as charge-storage and energy-converting materials for batteries and photoactive units of photovoltaic cell devices, respectively. They can be also used as substrates for electrochemical sensors and biosensors. Films of the C60/Pt and C60/Pd polymers containing metallic nano-particles of platinum and palladium, respectively, effectively catalyze the hydrogenation of olefins and acetylenes. Laser ablation of electrochemically formed C60/M and C70/M polymer films (M=Pt or Ir) results in fragmentation of the fullerenes leading to the formation of hetero-fullerenes, such as [C59M]+ and [C69M]+.Dedicated to Professor Dr. Alan M. Bond on the occasion of his 60th birthday.  相似文献   

12.
Three lanthanide coordination polymers incorporating 5‐hydroxyisophthalate ( L ) and phen ligands, [Eu( L )(phen)]n ( 1 ) and [Ln( L )(phen)2]n [Ln = Sm ( 2 ) and Pr ( 3 )], were synthesized. X‐ray structural analysis reveals that 1 features a (3,6)‐connected 3D rtl topology. Complexes 2 and 3 are isostructural and have 2D sheets with 63 topology. Comparison of the structural differences between 1 and 2 (or 3 ) suggests that the different metal sources play an important role in the formation of such coordination networks. Compounds 1 and 2 show photoluminescence and their emission properties are closely related to their corresponding central LnIII atoms.  相似文献   

13.
Pure gas and hydrocarbon vapor transport properties of blends of two glassy, polyacetylene-based polymers, poly(1-trimethylsilyl-1-propyne) [PTMSP] and poly(1-phenyl-1-propyne) [PPP], have been determined. Solid-state CP/MAS NMR proton rotating frame relaxation times were determined in the pure polymers and the blends. NMR studies show that PTMSP and PPP form strongly phase-separated blends. The permeabilities of the pure polymers and each blend were determined with hydrogen, nitrogen, oxygen, carbon dioxide, and n-butane. PTMSP exhibits unusual gas and vapor transport properties which result from its extremely high free volume. PTMSP is more permeable to large organic vapors, such as n-butane, than to small, permanent gases, such as hydrogen. PPP exhibits gas permeation characteristics of conventional low free volume glassy polymers; PPP is more permeable to hydrogen than to n-butane. In PTMSP/PPP blends, both n-butane permeability and n-butane/hydrogen selectivity increase as the PTMSP content of the blends increases. © 1996 John Wiley & Sons, Inc.  相似文献   

14.
Poly(silylenemethylene)s of the types [SiMeRCH2]n and [SiHRCH2]n were prepared by the ring-opening polymerization (ROP) of 1,3-disilacyclobutanes (DSCBs) containing n-alkyl substituents, such as C2H5, n-C3H7, n-C4H9, n-C5H11, and n-C6H13, or a phenyl group on the Si. These new polymers include a monosilicon analog of poly(styrene), [SiHPhCH2]n. Improved synthesis routes to the DSCB monomers were developed which proceed through Grignard ring closure reactions on alkoxy-substituted chlorocarbosilanes. All of these asymmetrically substituted polymers were obtained in high molecular weight form, except for [SiHPhCH2]n. The configurations of all of the polymers were found to be atactic. The aryl-substituted polymers have higher glass transition temperatures (Tgs) and thermal stability than those of the alkyl-substituted poly(silylenemethylene)s. Unlike the polyolefins of the type [C(H)(R)CH2]n, where Tg drops continuously from R = Me to n-Hex, the Tgs of the n-CnH2n+1 (n = 2–6)-substituted [SiMeRCH2]n PSM's appear to reach a maximum (at −61°C) for the R = n-Pr-substituted polymer. Moreover, where it was possible to make direct comparisons among similarly substituted atactic polymers, all of the poly(silylenemethylene)s were found to have lower Tgs than their all-carbon analogs. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3193–3205, 1997  相似文献   

15.
Four coordination polymers, namely, [Zn2(TIYM)(2,6‐PYDC)2]n · n(CH3OH) · 3n(H2O) ( 1 ), [Cu(TIYM)(2,6‐PYDC)]n · 3n(H2O) ( 2 ), [Co(TIYM)(2,6‐PYDC)]n · n(CH3OH) · 3n(H2O) ( 3 ), and [Cd2(TIYM)(2,6‐PYDC)2(H2O)]n · n(H2O) ( 4 ) with the flexible N‐containing ligand [tetrakis(imidazol‐1‐ylmethyl)methane (TIYM)] and the N‐containing dicarboxylic acid [2,6‐pyridinedicarboxylic acid (2,6‐PYDC)] were prepared. Compounds 1 – 4 show various structures because of different N–Ccenter–N angles (θ) of TIYM ligands and changing coordination modes of 2,6‐PYDC. Compounds 1 , 2 , and 3 display a similar 1D ladder‐like chain, whereas 4 gives a 1D quad‐core lifting platform shaped belt. The structural diversities in 1 – 4 suggest that the multiple coordination modes or the different freely twist angles of ligands and the presence of different metal atoms play important roles in the resulting structures of the coordination polymers. Furthermore, the solid‐state luminescence properties of 1 and 4 , and the magnetic properties of 3 were investigated.  相似文献   

16.
Systematic variation of the 1,4-dioxane (dx) concentration during the precipitation of sparingly soluble [MgBr2(dx)2] from ethereal Grignard solutions of RMgBr has allowed the structural investigation of crystallized [R2Mg(dx)n] (n=1, 1.5, 2, and 3), which form during this dioxane method, depending on the bulkiness of R. The numbering of the complexes explored in this study is based on the number n of dioxane molecules per magnesium atom, followed by the substituent R; an apostrophe denotes coordination polymers. The following derivatives were studied by X-ray crystal-structure determination and NMR spectroscopy: n=1: [Me2Mg(μ-dx)] ( 1′-Me ) and [nPr2Mg(μ-dx)] ( 1′-nPr ); n=1.5: [{iPr2Mg(dx)}2(μ-dx)] ( 1.5-iPr ), [{oTol2Mg(dx)}2(μ-dx)] ( 1.5-oTol ), and [(Me3Si-C≡C)2Mg(dx)1.5] ( 1.5′-C2SiMe3 ); n=2: [tBu2Mg(dx)2] ( 2-tBu ) and [oTol2Mg(dx)2] ( 2-oTol ); n=3: [Ph2Mg(dx)3] ( 3-Ph ). In the structure types 1′ , 1.5 , and 2 , the magnesium atom exhibits the coordination number 4, whereas pentacoordinate metal atoms are observed in types 3 and 1.5′ . The structure type 2′ is realized for [(Ph-C≡C)2Mg(dx)2] ( 2′-C2Ph ), [MgCl2(dx)2] ( 2′-Cl ), and [MgBr2(dx)2] ( 2′-Br ) with hexacoordinate metal atoms. The solubility of the dioxane adducts in common organic solvents strongly depends on the degree of aggregation with the solubility decreasing from molecular to strand to layer structures.  相似文献   

17.
Si-containing mono- and disubstituted polyacetylenes(? [CMe?C(SiMe3)] n? , ? [CH?H(n? C5H11)SiMe3]n? , etc.) underwent degradation in air; many of them exhibited relatively high yields of main-chain scission (Gs > 1). The Gs values for the polymers having a long n-alkyl group were usually large (ca. 2). In contrast, no polymer degradation occurred in vacuum, indicating that oxygen is necessary for the radiolysis. The polymers irradiated in air contained C?O and Si? O groups, and dissolved in polar solvents, which are nonsolvents of the starting polymers. From the radiation sensitivity and thermal degradability of these polymers, it is concluded that disubstituted polymers with high Si contents (? [CMe?C(SiMe3)]n? , ? [CMe?C(SiMe2CH2SiMe3)]n? , etc.) are not only radiation-sensitive but also thermally stable.  相似文献   

18.
This work investigates effects of poly(γ-butyrolactone) (PγBL) with different initiation and termination chain ends on five types of materials properties, including thermal stability, thermal transitions, thermal recyclability, hydrolytic degradation, and dynamic mechanical behavior. Four different chain-end-capped polymers with similar molecular weights, BnO-[C(=O)(CH2)3O]n-R, R = C(=O)Me, C(=O)CH=CH2, C(=O)Ph, and SiMe2CMe3, along with a series of uncapped polymers R′O-[C(=O)(CH2)3O]n-H (R′ = Bn, Ph2CHCH2) with Mn ranging from low (4.95 kg mol−1) to high (83.2 kg mol−1), have been synthesized. The termination chain end R showed a large effect on polymer decomposition temperature and hydrolytic degradation, relative to H. Overall, for those properties sensitive to the chain ends, chain-end capping renders R-protected linear PγBL behaving much like cyclic PγBL. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2271–2279  相似文献   

19.
Two coordination polymers, [Ba(H2L)(H2O)]n·nH2O (1) and [La(HL)(H2O)]n·nH2O (2) (Na2H2L = 4,5-dihydroxy-1,3-benzenedisulfonic acid disodium salt), have been synthesized under hydrothermal conditions. The central metal ions are nine-coordinate with distorted tricapped trigonal prismatic arrangements. Compounds 1 and 2 have 3-D metal–organic framework (MOF) structures which are created by 2-D inorganic layers [Ba2S2O5]n and [La2S2O5]n through organic phenyl moieties of HL3? linkages. The inorganic layers and organic pillars are alternately arranged to generate the 3-D pillared-layered open frameworks with (411, 64) topologies. Results of fluorescence measurements reveal that two decayed emission bands centered at 435 and 408 nm may be caused by interactions of the ligands and the metal ions. The respective luminescence emission peaks appear at different wavelengths and intensities, which can be affected by the metal ions.  相似文献   

20.
Polymerization of 1-methylthio-1-alkynes (MeSC?CR; R = Et, n-Bu, n-C6H13, and n-C8H17) was studied by use of transition metal catalysts. A 1 : 2 mixture of MoCl5 and Ph3SiH provided polymers having M?w over 1 × 105 in 30–50% yields from these monomers. The length of the alkyl group hardly affected the polymerization. The monomer, MeSC?C-n-C6H13, showed low reactivity in homopolymerization, but higher reactivity than that of MeC?C-n-C5H11 in copolymerization. Poly(1-methylthio-1-alkyne)s were colorless solids, and those with long alkyl pendants (R = n-C6H13, n-C8H17) were soluble in various organic solvents. The present polymers were thermally more stable than poly(2-alkyne)s, the corresponding hydrocarbon polymers.  相似文献   

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