PERFLUORO-AND POLYFLUORO-SULFONIC ACIDS (ⅩⅤ)——GENERATION OF DIFLUOROCARBENE AND FLUOROSULFONYLDIFLUOROMETHIDE ION FROM METHYL α-FLUOROSULFONYLDIFLUOROACETATE

The decarbomethoxylation reactions of MeOCOCF_2SO_2F (1) can be induced readily by a varietyof nucleophiles. For example, X~- (Cr~-, Br~-, I~-), CNS~-, Et_3N, C_5H_5N make facile attack onmethyl carbon of 1 with subsequent elimination of CO_2, SO_2 and F~- resulting in generation of CF_2:. Innonaqueous organic solvents fragmentation of 1 was extremely fast and apparently might take place withsimultaneous elimination of SO_2 and F~- and formation of CF_2:. In aqueous organic solvents the inter-mediate FSO_2CF_2~- may be trapped by protonation into HCF_2SO_2F (2) as well as predominantly furthereliminate SO_2 and F~- yielding CF_2:. Alkoxide ions could not decompose 1 to produce CF_s:, but wereable to attack the sulfur atoms to afford the corresponding sulfonates, MeOCOCF_2SO_2Z (10) (Z=OCH_2-CF_2CF_2H, OC_6H_5). In the absence of solvent Et_2NH mainly induced the decomposition of 1 to form CF_2:with some attack on carboxyl carbon to give the corresponding amide FO_2SCF_2CONE_(t2).     

SYNTHESIS AND CRYSTAL STRUCTURE OF TWO NOVEL CARBENE AND CARBYNE COMPLEXES OF RHENIUM

The cationic carbyne complex of rhenium, [π-C_5H_5(CO)_2ReCC_6H_5] BBr_4(Ⅰ), in tetrahy-drofuran reacted with 1-lithiocarborane at low temperature, with addition of the carbo-ranyl anion to earbyne earbon and carbonyl carbon atoms to give two novel carbene andcarbyne complexes of rhenium, π-cyclopentadienyl (dicarbonyl) [(1-earboranyl) (phenyl)carbene] rhenium π-C_5H_5 (CO)_2ReC (C_2HB_(10)H_(10)) C_6H_5, (Ⅱ) and π-cyclopentadienyl-(carbonyl)(1-carboranylformacyl) (phenylcarbyne) rhenium π-C_5H_5 (CO) (COC_2HB_(10)H_(10)) ReCC_6H_5 (Ⅲ).This fact indicates that there are two electrophilic centers in the cationic carbyne complexⅠ. At room temperature the complex Ⅲ in solution transformed gradually into the complexⅡ. The complexes Ⅱ and Ⅲ were identified by elemental analyses, IR, ~1H NMR and massspectra, and finally by their single crystal X-ray structure determinations. The possiblereaction mechanism is suggested and discussed in this paper.     

STUDY ON POLYMERIZATION MECHANISM OF 3, 9,-DIALLYL-3, 9, -DIBENZYL-1, 5, 7, 11-TETRAOXASPIRO [5, 5] UNDECANE

A new monomer, 3,9-diallyl-3, 9-dibenzyl-1, 5,7,11 - tetraoxa- spiro [5,5] undecane (6) was prepared by the reaction of 2- allyl- 2' - benzyl- propanediol - 1.3 with dibutyltin oxide, and then treated with CS_2. Monomer 4 could be initiated by cationic initiators to give a viscous polymer (white powder in the case of polymerization at 0℃). Upon the NMR and IR spectra of the obtained polymer, the components and their relative amount were estimated. The polymerization mechanism was discussed.     

SYNTHESIS OF POLY(SILPHENYLENE-SILOXANE) THROUGH DEHYDROCARBON POLYCONDENSATION OF 1,4-BIS(DIMETHYLSILYL)BENZENE AND DIALKOXYSILANE

Poly(silphenylene-siloxane)s had been synthesized through dehydrocarbon polycondensation of 1,4- bis(dimethylsilyl)benzene(BDSB)and dialkoxysilane.The polymer composition and structure was characterized by ~(29)Si-NMR.The influence of temperature,B(C_6F_5)_3 concentration and monomer structure on the composition and the microstructure of the copolymers were investigated.It shows that elevating reaction temperature or using substrate (R'O)_2R_2R_1Si with bulk organic group of R_1 or R_2 augments the run n...     

Addition of polyfluoroalkyl halides to 1-octeneinitiated by dichlorobis(π-cyclopentadienyl)-titanium and iron

Addition of various polyfluoroalkyl halides including 1,2-dihalopolyfluoroalkanes to1-octene is effected by using a catalytic amount of Cp_2TiCl_2(IV) and iron powder to give 1:1 adductsin excellent yields. The reaction is performed in EtOH or THF. A Cp_2TiCl(Ⅲ) mediatedradical mechanism is proposed. Radical reactivity of polyfluoroalkanes toward 1-octene was foundto be --CF_2I> -CF_2Br >-CF_2CCl_3.     

The reaction of perfluoroalkanesulfonyl halides Ⅶ. Preparation and reactions of trifluoromethanesulfonyl bromide

The reaction between sodium trifluoromethanesulfinate, which was prepared from trifluorome-thyl bromide, with bromine in aqueous solution resulted in the formation of trifluoromethanesulfonylbromide (CF_3SO_2Br). CF_3SO_2Br reacted with alkenes and alkyne to give the corresponding adductswith the loss of SO_2 in good yields, and with compounds containing active hydrogen to give brominatedderivatives. A radical reaction mechanism was proposed and confirmed by EPR study.     

Synthesis and Crystal Structure of a New Zn(Ⅱ) Coordination Polymer Constructed by 1,2,4,5-Benzenetetracarboxylate

A new Zn(Ⅱ) coordination polymer [Zn3(btec)(OH)2(H2O)2]n (1, btec = 1,2,4,5- benzenetetracarboxylate) has been synthesized by hydrothermal reaction and its structure was determined by single-crystal X-ray diffraction analysis. The title compound crystallizes in mono- clinic, space group C2/c, with a = 19.580(3), b = 5.0137(8), c = 15.975(3), β = 121.629(2)°, V = 1335.3(4)3, C10H8O12Zn3, Mr = 516.27, Z = 4, Dc = 2.568g/cm3, μ = 5.419 mm-1, F(000) = 1016, R = 0.0590 and Rw = 0.1279 for 1110 observed reflections (I > 2σ(I)). X-ray analysis shows that the asymmetric unit of the title compound contains two crystallographically unique Zn(Ⅱ) atoms which are connected through the bridging carboxylate oxygen atoms of the btec ligands and μ2-bridging oxygen atoms of water molecules to generate an infinite one-dimensional chain. The adjacent chains are linked together through the benzene rings of the btec ligands to form a two-dimensional polymeric network. The adjacent two-dimensional layers are further connected together by the benzene rings of btec ligands to give the final three-dimensional structure. The benzene rings act as pillars between two layers.     

SYNTHESIS AND POLYMERIZATION OF OLIGO (OXYETHYLENE) MACROMONOMER

This paper reports the synthesis of methoxyoligo (oxyethylene) methacrylate (MEO_n , n is the repeating unit number of (CH_2CH_2O) in the macromonomer), and its polymerization in different solvents. MEO_n is prepared through such two independent reactions as (1) anionic polymerization of oxirane initiated by potassium alkoxide and (2) end-capping of methoxy oligo(oxyethylene) by methacrylic group. The n value can be conveniently controlled over the range of 5 ～30 by varying the molar ratio of oxirane to initiator and the molecular weight distribution of MEO_n be narrowed by increasing reaction time only in step (1). MEO_n thus obtained shows a rapid polymerization in water and benzene respectively, and both give water-soluble polymers as long as suitable conditions are used.     

Construction of a 2D Cd(Ⅱ) Network with Homohelical Chains Based on 1,3-Dipyridyl Benzene(Dpb) and 4,4'-Sulfonyldibenzoic Acid(H_2sdb)

A two-dimensional(2D) coordination polymer {[Cd2(sdb)2(dpb)2]·3H2O}n(1) was prepared by solvothermal reaction of two types of V-shaped ligands: 1,3-dipyridyl benzene(dpb) and deprotonated 4,4'-sulfonyldibenzoic acid(H2sdb). It was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. Complex 1 crystallizes in the monoclinic system, space group Fdd2 with a = 46.247(10), b = 9.994(2), c = 24.267(6) , V = 11216(4) 3, C60H46Cd2N4O15S2, Mr = 1387.97, Dc = 1.559 g/cm3, F(000) = 5296.0, μ = 0.902 mm-1 and Z = 8. Each [Cd(COO)]2 cluster links four sdb2- anions to form infinitely ABAB stacked 2D wave-like sheets, in which each sheet contains the same helical chains, and the helical directions of sheets A and B are reversed. Dpb links the rest coordinated sites of [(COO)Cd]2 cluster to form a 2D network. In addition, the solid fluorescence of 1 and dpb is also studied.     

Direct synthesis of per(poly)fluoroalkylmethyl-substituted electrophilic cyclopropane derivatives

A convenient and direct per(poly)fluoroalkylmethyl-mtroducing cyclopropanation reaction was described. In the presence of CrCl3/Fe, per(poly)fluoroalkyl iodides reacted with diethyl allylmalonate and its analogs to give per(poly)fluoroalkylmethyl-substituted electrophilic cyclopropane derivatives in high yields. This reaction was considered to proceed by two steps: radical addition followed by cyclopropanation.     

Non-Isothermal Decomposion Kinetics of Supermolecule Compound [Eu(C_(10)H_9N_2O_4)(C_(10)H_8N_2O_4)(H_2O)_3]_2·phen·4H_2O

Europium(Ⅲ) compound with 2-oxopropionic acid salicyloyl hydrazone (C_(10)H_(10)N_2O_4,H_3L) and 1,10-phenan-throline (C_(12)H_8N_2,phen) has been prepared.A yellow prismatic crystal of the compound was obtained,and themolecule crystallized in the triclinic space group P-1.There are two 9-coordinated complex molecules in everystructure unit,where every Eu atom is coordinated by three water molecules and two tridentate C_(10)H_(10)N_2O_4 ligands,forming two stable pentacycles.The coordination polyhedron around Eu~(3+) was described as a single cap squareantiprism.In the crystal cell,there are one free 1,10-phenanthroline and four water molecules.The thermaldecomposition of the compound and its kinetics were studied by non-isothermal thermogravimetry.The Kissinger'smethod and Ozawa's method were used to calculate the activation energy value of the first-step decomposition.Thestages of the decompositions were identified by TG-DTG-DSC curve.The non-isothermal kinetic data were ana-lyzed by means of integral and differential methods.The possible reaction mechanism and the kinetic equationswere investigated by comparing the kinetic parameters.     

CHROMATOGRAPHIC SEPARATION ON GRAPHITE OF FULLERENE-C_(60) AND-C_(70)

The mixture of fullerene—C_(60) and —C_(70) was successfully separated in larger amount by liquid chromatogra-phy on graphite column.The column was first eluted with a mixture of hexane and toluene,and then withtoluene.The eluates were monitored by UV/visible absorption spectroscopy.Graphite column shows high perfor-mance for separation.and much larger quantities of pure C_(60) can be easily obtained.The synthesis of fullerenes(C_(60) and C_(70))in macroscopic quantities has stimulated scientists to study on themethod for separating C_(60) and C_(70).Because of the poor solubility of fullerenes C_(60)/C_(70) in most organic solvents,theseparation of C_(60) and C_(70) proved to be a challenging task.Most attempts at the separation have used silica and alu-mina as the stationary phase and a mixture of hexane and benzene(or toluene)as the mobile phase.Fullerenes,however,have only limited solubility in hexane,these separations are usually only achieved by limit-ing the amount of sample to a few milligrams.The hexane-silica technique using phenylglycine based HPLCcolumns appears to offer good separation,but only for submilligram amounts. The use of graphite powder as the stationary phase in liquid chromatography is an advanced separation tech-nique for fullerenes C_(60)/C_(70).The technique is based on that the fullerene-C_(60) is different from C_(70) in the de-gree of electron delocalisation,and C_(60) is much less diamagnetic than C_(70).It is expected that the dissimilarity willcause the C_(60)/C_(70) molecules to exhibit different interactions with graphite,and can be separated from each other onthis basis.     

Synthesis and Crystal Structure of [Cd(NBA)(μ_3-OH)(4,4′-bipy)_(1/2)]_n

A new cadmium polymer [Cd(NBA)(μ3-OH)(4,4′-bipy)1/2]n 1 (NBA = m-nitrobenzoic acid and 4,4′-bipy = 4,4-bipyridine) has been synthesized by hydrothermal reaction. Its structure was determined by single-crystal X-ray diffraction method, and characterized by elemental analysis and IR spectrum. The crystal is of monoclinic, space group C2/c, with a = 15.6912(9), b = 25.9394(15), c = 6.7332(4) ′, β = 114.7700(10)°, V = 2488.4(3) 3, C12H9CdN2O5, Mr = 373.61, Z = 8, Dc = 1.995 g/cm3, μ = 1.776 mm-1, F(000) = 1464, R = 0.0411 and wR = 0.1128 for 2130 observed reflections (I > 2σ(I)). X-ray diffraction studies reveal that the compound features a layered structure, in which 4,4′-bipy ligands bridge Z type of double chains [Cd(μ3-OH)]n and NBA ligands locate at the two sides of the layer. The π-π interactions between the benzene rings of NBA ligands of two adjacent layers lead to the 3D framework.     

A 2D Layer Copper(Ⅱ) Coordination Polymer with 3-Nitrophthalic Acid: Synthesis,Crystal Structure and Copper 3-Nitrophthalate Metal-organic Framework-graphene Oxide Nanocomposite

A 2D layer Cu(Ⅱ) coordination polymer [Cu(npth)(H_2O)]n(1) was crystallized from a mixture of 3-nitrophthalic acid and Cu(OAc)_2·H_2O in water under room temperature and structurally characterized by single-crystal X-ray diffraction, FT-IR and TGA. Compound 1 was applied to make a nanocomposite with graphene oxide(GO). A highly dispersible and stable nanocomposite of Cu(npth)-GO was successfully synthesized by a simple ultrasonication method. SEM, TEM, UV-vis, FT-IR and TGA were used to characterize the morphology and structure of the prepared composite. In accordance with the characterization results, we suspected that the binding mechanism of Cu(npth) and GO was assigned to be the cooperative interaction of Cu–O coordination, π-π stacking and hydrogen bonding.     

Synthesis,Structure, and Properties of {[Mn(ADA)(Phen)]·(H_2O)_2}_n Constructed from Azobenzene-4,4?-dicarboxylic Acid and 1,10-Phenanthroline

One coordination polymer(CP) {[Mn(ADA)(Phen)](H_2O)_2}_n(1, H_2ADA = azobenzene-4,4?-dicarboxylic acid, Phen = 1,10-phenanthroline), has been synthesized via hydrothermal reactions. CP 1 was characterized by elemental analyses, IR spectra, thermal behaviors, and X-ray single-crystal diffraction. In CP 1, each ADA~(2-) ligand bridges two Mn~(2+) to give one-dimensional zigzag chains with the Mn···Mn separations of 17.6911 and 16.3976 ?, which generates a three-dimensional supramolecular structure by means of strong π···π interaction and hydrogen bonding. It crystallizes in triclinic, space group P1, with a = 7.6200(13), b = 9.1530(15), c = 18.262(2) ?, α = 88.467(3)o, β = 84.145(2)o, γ = 77.542(2)o, V = 1237.2(3) ?~3, Z = 2, C_(26)H_(20)MnN_4O_6, Mr = 539.40, Dc = 1.448 g/cm~3, F(000) = 554, S = 1.018, R = 0.0531 and w R = 0.1094. In addition, natural bond orbital analysis was performed by the B3 LYP/LANL2 DZ method of Gaussian 09 Program. The fluorescence, magnetic, and electrochemical properties of 1 have been investigated.     

Synthesis,Structure and Luminescent Properties of Cd(Ⅱ) Coordination Polymers Based on 4-Nitrobenzoic Acid and Bis(imidazol) Ligand

A new Cd(Ⅱ) coordination polymer, [Cd_(0.5)(nba)(bib)_(0.5)]_(2n)(1, Hnba = 4-nitrobenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane), was synthesized at room temperature condition and characterized by IR spectra, elemental analyses, single-crystal and powder X-ray diffractions. Complex 1 belongs to the monoclinic system, C2/c space group, with a = 26.0600(14), b = 6.7889(4), c = 16.5825(9) ?, β = 118.8120(10)°, V = 2570.6(2) ?3, Z = 4. It shows one-dimensional chains and is further linked by π-π stacking interactions to yield a three-dimensional supramolecular structure. Thermal stability and luminescence of 1 were investigated.     

Structure and Fluorescence Property of a 2D Bilayer Cd(Ⅱ) Coordination Polymer Induced by H-bonding and π-π Interaction

Solvothermal reactions of 4,4'-oxybis(benzoic acid) (H2oba) with 1,3-dipyridyl benzene (1,3-dpb) produced a two-dimensional (2D) cadmium(Ⅱ) coordination polymer {[Cd(oba)(dpb)]·H2O}n (1). The complex was characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/c with a = 13.6692(9), b = 25.9647(17), c = 8.7912(6) , α = 125.0370(10), γ = 2544.7(3)°, V = 2544.7(3) 3, C30H22N2O6Cd, Mr = 618.91, Dc =1.609 g/cm3, F(000) = 1248, μ = 0.904 mm-1 and Z = 4. The neighboring Cd(Ⅱ) ions are linked by oba2-anions and 1,3-dpb to form an infinitely 2D wavelike sheet, and two such 2D sheets are interlocked with each other by H-bonding to form a 2D → 2D structure. The adjacent two groups of interlocked structures are further linked to form a bilayer 2D supramolecular network by π-π interactions. In addition, the fluorescence property of 1 was also studied.     

POLYBINAPHTHYLS INCORPORATING (R)-2,2''''-BINAPHTHO-20-CROWN-6 AND NAPHTHYL MOITIES

Chiral polymer was synthesized by the polymerization of (R)-6,6'-bistributylstannyl-2,2'-binaphtho-20-crown-6 (M-1) with 1,4-dibromo-2,3-bisbutoxy-naphthyl (M-2) by Pd(PPh3)4 catalyzed Stille coupling reaction. Both monomer and polymer were analyzed by NMR, MS, FT-IR, UV, polarimetry, DSC-TGA, CD, fluorescent spectroscopy and GPC. The major difference between monomer and polymer is that a long wavelength Cotton Effect was observed for the polymer due to its more extended conjugation in the repeating unit and a highly rigid backbone in the polymer chain. Polymer has strong blue fluorescence due to the efficient energy migration from the extended n-electronic structure of the repeating unit of the polymer to the chiral binaphthyl core and is expected to have potential application in the materials of fluorescent sensors and chiral chromatographic packing for resolution of racemic amino acid.     

Synthesis,Crystal Structure and Luminescence Properties of a Cadmium(Ⅱ) Complex Based on 2-Hydroxy-6-methylisonicotinic Acid

A new cadmium(Ⅱ) complex[Cd(Hminic)(IP)]_n(1,Hminic = 2-hydroxy-6-methylisonicotinic acid,IP = imidazo[4,5-f]-l,10-phenanthroline),has been synthesized by the reaction of a Hminic and auxiliary N-containing ligands with Cd(Ⅱ) ion under hydrothermal conditions.The complex was studied by elemental analysis,IR spectroscopy and X-ray crystallography.It is formulated as C_(20)H_(13)CdN_5O_3,crystallizes in monoclinic system,space group C2/c with α=9.6764(8),b = 26.767(2),c = 14.1332(11) A and β= 97.4510(10)°.V= 3629.7(5) A~3,Z = 8,Mr=483.75,D_c = 1.770 g/cm~3,F(000) = 1484 and μ= 1.237 mm~(-1).The final refinement gave R = 0.0309 and wR = 0.0703 for 4151 reflections with I 2σ(I).In the structure of 1,two Cd(Ⅱ) atoms are joined by a pair of μ_2-hydroxyl oxygen atoms giving rise to a dinuclear Cd(Ⅱ) unit which is bridged by Hminic linkers to form a 1D ladder-like polymer chain.The chelating ligand IP coordinated to the Cd(Ⅱ) atom,and alternately attached to both sides of the ladder-like polymer chain.Adjacent chains are further bound together by strong intermolecular hydrogen bonds and face-to-face π…πinteractions,resulting in the formation of a 3D supramolecular architecture.Furthermore,the thermal stability and luminescent properties of this complex and the free ligands have been investigated.     

Synthesis,Characterization and Thermostability of a Novel Pb(Ⅱ) Coordination Polymer with Mixed Ligands

A novel mixed-ligand coordination polymer [Pb(phen)(NNDS)(H2O)]n·n H2O(1) was obtained from the reaction of 1,10-phenanthroine(phen), Pb(OAc)2 and sodium 1-nitroso-2-naphthol-3,6-disulfonate(Na2NNDS) in a mixed solvent. The complex was characterized by elemental analysis, IR and X-ray single-crystal diffraction. Crystal data for 1: monoclinic, space group P21/c, a = 11.5835(9), b = 14.6334(11), c = 13.9030(11) ?, β = 98.4180(10)o, V = 2331.3(3) ?3, Z = 4, Mr = 754.70, Dc = 2.150 mg/m3, μ = 7.483 mm-1, F(000) = 1456, the final R = 0.0430 and w R = 0.0841 for 4221 observed reflections with I 2σ(I). The Pb(II) center is coordinated by six O and two N atoms showing a distorted dodecahedron configuration. The multidentate ligand of NNDS dianion exhibits peculiar coordination mode, and the two O atoms of two sulfonate anions bridge two Pb(II) cations into a dimer, and the O atom of nitroso group links the other dimer into 2D sheets extending in the [011] plane. There exist significant π-π stacking interactions between adjacent phen and NNDS. The 3D network is formed by 2D sheets interlinked by hydrogen bonds and π-π stacking interactions. The thermostability of 1 was investigated by TG and DSC.