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Novel organic–inorganic hybrid coating materials were developed using amino silanes and acetoacetylated soybean oil. The acetoacetylated soybean oil was prepared from soybean oil (a renewable resource) using a solvent-free method involving a thiol–ene and transesterification reactions, and the chemical structure was characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), Fourier-transform infrared (FTIR) spectroscopy, and viscosity analyses. On the basis of the acetoacetylated soybean oil, several organic–inorganic hybrid coating materials were prepared using different amino silanes by a catalyst-free method involving one-step comprising two reactions (an amine–acetoacetate reaction and an in situ sol–gel technique), and their crosslinked structures were determined from their FT-IR and solid-state 29Si NMR spectra. The resulting coating materials have good mechanical/chemical performance. This method for preparing renewable organic–inorganic hybrid coating materials may have wide uses because plant oils contain many unsaturated CC bonds and easy access to acetoacetate functional groups.

A novel ambient-cured coating film obtained via a Knoevenagel and Michael addition reactions between modified acetoacetylated castor oil and a crosslinker that contain both aldehyde and acrylate groups was developed. The modified acetoacetylated castor oil was synthesized via thiol-ene coupling and transesterification reactions and was characterized by NMR, FTIR, and viscosity analyses. The coating films prepared by the Knoevenagel addition reaction, Michael addition reaction, and Knoevenagel and Michael addition reactions coating film are discussed. The tensile and thermal properties of the obtained coating films were investigated by dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results demonstrated that the Knoevenagel and Michael addition reactions coating film has a good balance of properties. Moreover, we also prepared films with different crosslinkers by Knoevenagel and Michael addition reactions and found that the films have good properties, including glass transition temperature (41%–54%), pencil hardness (3 H), and tensile properties (1.17 MPa – 2.23 MPa). Overall, the film made via Knoevenagel-Michael addition technology provides an excellent bio-based coating system.

A new anilido-imine tetra-azane ligand 1,2-[2′-(2′′,6′′-iPr2C6H3NCH)C6H4NH]2C6H4 (LH2) was synthesized and characterized. One-pot direct HCl-elimination reactions of LH2 with MCl4 (M = Ti, Zr, Hf) in toluene at room temperature at first and then at 140 °C under vacuum afforded LMCl2 [M = Ti (1a), Zr (1b), Hf (1c)] in high yields (57 ∼ 75%). It is for the first time the Zr and Hf complexes are being synthesized by the one-pot direct HCl-elimination reactions of MCl4 with a weak acidic amine-containing free ligand. All new complexes were characterized by 1H and 13C NMR spectroscopy and the molecular structures of 1a, 1b and 1c were determined by single crystal X-ray diffraction analysis. The metal centers in all complexes are six-coordinated with a distorted octahedral geometry. Upon activation with MAO or AliBu3/Ph3C+B(C6F5)4−, these complexes exhibit moderate catalytic activity for ethylene polymerization. The AliBu3/Ph3C+B(C6F5)4− activated catalyst systems produce polyethylene with ultra-high molecular weight (viscosity-averaged molecular weight Mη up to 4.29 × 106 Dalton) while the MAO activated catalyst systems show relatively good thermostability.

Two new anilido-imine tetra-azane ligands, 1,2-[(2′-(ArNH)C6H4HC N)]2C6H4 (Ar = 2,6-Me2C6H3 (L1H2) and 2,6-iPr2C6H3 (L2H2)), were synthesized by the condensation reaction of o-phenylenediamine with the corresponding 2-(arylamino)benzaldehyde, and their zirconium and hafnium complexes, L1MCl2 (M = Zr (1b), Hf (1c)) and L2MCl2 (M = Zr (2b), Hf (2c)), were synthesized in high yields (61–66%) by the reactions of L1Li2 and L2Li2 with MCl4 in toluene. Direct HCl-elimination reactions of L1H2 with MCl4 (M = Ti, Zr, Hf) in toluene at 140 °C under vacuum afforded the products L1HMCl3 [M = Ti (1a′), Zr (1b′), Hf (1c′)] with a partially deprotonated tridentate ligand in good to high yields (48–70%). All the new complexes were characterized by 1H and 13C NMR spectroscopy and the molecular structures of 1b and 2c were determined by single crystal X-ray diffraction analysis. The metal centers in both complexes are six-coordinated with a distorted octahedral geometry. Upon activation with MAO or AlR3/Ph3CB(C6F5)4, complexes 1b–1c and 2b–2c all exhibit moderate catalytic activity for ethylene polymerization and produce linear polyethylene with ultra-high molar masses (100–184 × 104 g/mol).

Through the collection, collation and analysis of the data about damage of Water tower in Shaanxi Provence during 12 May 2008 Wenchuan Earthquake, the mechanism of long-period damage of the water tower is given. The analysis shows that, in Hanzhong basin, Ankang basin, and Weihe basin, serious damage should be caused by the long-period effect of basin of large earthquake in the far field. That magnitude of Wenchuan Earthquake is high, three basins are at the direction where the Wenchuan Earthquake wave propagated, and the epicentre is from 400 to 600km determines that the Wenchuan earthquake has the condition producing long-period effect in the three basins. In addition, the basins have very thick deposits, as well as possible basin edge effect may enhance long period damage. The damage of long-period of water tower results from the resonance between water tower and long-period ground motion.

The N,N,N-tridentate quinolinyl anilido–imine ligands 2-(ArNC(H))C6H4–HNC9H6N (LaH, Ar = 2,6-Me2C6H3; LbH, Ar = 2,6-iPr2C6H3) and 2-(C9H6N)NC(H)C6H4–HNAr (LcH, Ar = 2,6-Me2C6H3; LdH, Ar = 2,6-iPr2C6H3) were synthesized and characterized. Reactions of these ligands with nBuLi and subsequent additions of NiCl2(DME) afford the N,N,N-tridentate nickel complexes [2-(ArNC(H))C6H4–NC9H6N]NiCl (Ar = 2,6-Me2C6H3 (1a), 2,6-iPr2C6H3 (1b)) and [2-(C9H6N)NC(H)C6H4–NAr]NiCl (Ar = 2,6-Me2C6H3 (2a), 2,6-iPr2C6H3 (2b)). All the complexes were fully characterized by NMR and elemental analyses. X-ray diffraction analyses of 1b and 2b revealed an almost square-planar geometry around the metal center. When activated with MAO, these nickel complexes can be used as catalysts for the vinyl addition polymerization of norbornene affording high molecular weight polymer.

A series of tridentate anilido-imine [N,N,O] ligands 2-(2-(R12-2,6-C6H3NH)C6H4)HC═N(4-tBu-6-R2-C6H2OH) [R1 = Me, R2 = tBu (LaH2); R1 = Et, R2 = tBu (LbH2); R1 = iPr, R2 = tBu (LcH2); R1 = Me, R2 = Ad (LdH2); R1 = Et, R2 = Ad (LeH2); R1 = iPr, R2 = Ad (LfH2)] were synthesized and characterized. Reaction of the free ligand LdH2 with TiCl4 in toluene at low temperature affords the zwitterionic complex Ld+H2Ti–Cl4 (1d). The zwitterionic complex can be dissolved in THF to form THF-solvated complex 1d′. Heating 1d in toluene at 40 °C affords the neutral complex LdHTiCl3 (2d) by losing a HCl. Complex 2d can be fully converted to the final complex LdTiCl2 (3d) at 140 °C under vacuum by losing another HCl. Complexes 3a–3c, 3e, and 3f were also synthesized in high yields in the same one-pot procedure. All complexes were characterized by 1H and 13C NMR spectroscopy, and the molecular structures of 1d′, 3b, 3d, and 3e were determined by single-crystal X-ray diffraction analysis. The titanium centers in complexes 3b, ...

2-Amino 3-substituted-quinazolin-4(3H)-one derivatives were synthesized from Pbf-isothiocyanate and methyl anthranilate. The construction of the guanidine-containing quinazolinone heterocyclic skeleton was achieved using Pbf-activated thiourea treated with primary amines via iodine-mediated guanidinylation. The desired compounds were obtained after Pbf cleavage by trifluoroacetic acid.

Reactions of 2,6-(ArN═CH)2C6H3Li with CrCl2(THF)2 afford two trinuclear bis(imino)aryl NCN pincer Cr(II) complexes {[2,6-(ArN═CH)2C6H3]Cr(μ-Cl)2}2Cr [Ar = 2,6-Me2C6H3 (1a), 2,6-Et2C6H3 (1b)], and a mononuclear bis(imino)aryl NCN pincer Cr(II) complex [2,6-(ArN═CH)2C6H3]Cr(μ-Cl)2Li(THF)2 [Ar = 2,6-iPr2C6H3 (1c)], respectively. Similar reactions of 2,6-(ArN═CH)2C6H3Li with CrCl3(THF)3 produce only mononuclear bis(imino)aryl NCN pincer Cr(III) complexes [2,6-(ArN═CH)2C6H3]CrCl2(THF) [Ar = 2,6-Me2C6H3 (2a), 2,6-Et2C6H3 (2b), 2,6-iPr2C6H3 (2c)]. X-ray crystallographic analysis reveals that the terminal Cr(II) atoms in 1a and 1b and the Cr(II) atom in 1c possess a distorted trigonal bipyramidal coordination environment with the Cipso atom of the pincer ligand and two chloride atoms in the equator and the two imine nitrogen atoms in the apical positions, while the Cr(III) complexes 2a, 2b, and 2c all adopt a distorted octahedral geometry around the chromium metal. Upon activation with trialkylaluminum and [Ph3C]...

The graft copolymerization of butyl acrylate onto poly(vinyl alcohol) with eerie ammonium nitrate as redox initiator in a aqueous medium has been investigated. The formation of graft copolymer was confirmed by means of IR, scanning electron microscopy (SEM), and wide-angle X-ray diffraction (WAXD). The percentage of mononer conversion and percentage of grafting varied with concentrations of initiator, nitric acid, monomer, macromolecular backbone (X-n = 1750, M = 80 000), reaction temperature and reaction time. Some inorganic salts and organic solvents have a great influence upon grafting. The reaction mechanism has been explored, and rate equations for the reaction are established. (C) 2000 John Wiley & Sons, Inc.

Substituted 2-(N-alkylamino)-pyrimidin-4-ones were synthesized from N-alkyl β-amino acid esters starting with guanidinylation using Pbf-activated thiourea. The six-membered pyrimidinones were obtained in good yields via intramolecular cyclization during TFA cleavage of the Pbf protecting group.

Title compounds are prepared using the Pbf-activated thiourea moiety as guanidinylating reagent in the ring closure reaction step.

Five new chiral liquid crystal systems induced by intermolecular hydrogen bonding between 4-[(s)-2-chloro-3-methyl]butyroyloxy-4′-stilbazole (MBSB, proton acceptor) and 4-alkoxybenzoic acids (nBA, proton donors) were prepared. Their liquid crystalline properties were investigated by DSC and polarized optical microscopy. Chiral nematic and chiral smectic phases were observed, and the thermal stability of one complex was studied through temperature dependent infrared spectroscopy.

Reactions of N,N,N-tridentate quinolinyl anilido-imine ligands with AlMe(3) afford mononuclear aluminum complexes {κ(3)-[{2-[ArN=C(H)]C(6)H(4)}N(8-C(9)H(6)N)]}AlMe(2) (Ar = 2,6-Me(2)C(6)H(3) (1a), 2,6-Et(2)C(6)H(3) (1b), 2,6-(i)Pr(2)C(6)H(3) (1c)) or dinuclear complexes AlMe(3){κ(1)-[{2-[ArN=C(H)C(6)H(4)]N(8-C(9)H(6)N)}-κ(2)]AlMe(2) (R = 2,6-Me(2)C(6)H(3) (2a), 2,6-Et(2)C(6)H(3) (2b), 2,6-(i)Pr(2)C(6)H(3) (2c)) depending on the ratios of reactants used. Similar reactions of ZnEt(2) with these ligands give the monoligated ethyl zinc complexes {κ(3)-[{2-[ArN=C(H)]C(6)H(4)}N(8-C(9)H(6)N)]}ZnEt (Ar = 2,6-Me(2)C(6)H(3) (3a), 2,6-Et(2)C(6)H(3) (3b), 2,6-(i)Pr(2)C(6)H(3) (3c)) or bisligated complexes {κ(3)-[{2-[ArN=C(H)]C(6)H(4)}N(8-C(9)H(6)N)]}Zn{κ(2)-[{2-[ArN=C(H)]C(6)H(4)}N(8-C(9)H(6)N)]} (Ar = 2,6-Me(2)C(6)H(3) (4a), 2,6-Et(2)C(6)H(3) (4b), 2,6-(i)Pr(2)C(6)H(3) (4c)). These complexes were well characterized by NMR and the structures of 1a, 2a, 2c, 3b and 4c were confirmed by X-ray diffraction analysis. The aluminum and zinc complexes were tested to initiate lactide polymerization in which the zinc complexes show moderate to high activities in the presence of benzyl alcohol.

A number of new half-sandwich zirconium(IV) complexes bearing N,N-dimethylaniline-amido ligands with the general formula Cp*ZrCl(2)[ortho-(RNCH(2))(Me(2)N)C(6)H(4)] [R = 2,6-Me(2)C(6)H(3) (1), 2,6-(i)Pr(2)C(6)H(3) (2), (i)Pr (3), (t)Bu (4)] were synthesized by the reaction of Cp*ZrCl(3) with the corresponding ortho-(Me(2)N)C(6)H(4)CH(2)NRLi. All new zirconium complexes were characterized by (1)H and (13)C NMR, elemental analyses and single crystal X-ray diffraction analysis. The molecular structural analysis reveals that the NMe(2) group does not coordinate to the zirconium atom in all cases. Complexes 1-4 all have a pseudo-tetrahedral coordination environment in their solid state structures and adopt a three-legged piano stool geometry for the zirconium atoms with the amide N atom and the two Cl atoms being the three legs and the Cp* ring being the seat. Variable-temperature (1)H NMR experiments for all complexes 1-4 were performed to investigate the possible intramolecular interaction between the N atom in the NMe(2) group and the central zirconium atom in solution. Upon activation with Al(i)Bu(3) and Ph(3)CB(C(6)F(5))(4), complexes 1-4 all exhibit moderate to good catalytic activity for ethylene polymerization and copolymerization with 1-hexene, producing linear polyethylene or poly(ethylene-co-1-hexene) with moderate molecular weight and reasonable 1-hexene incorporation.

A series of new titanium(IV) complexes with symmetric or asymmetric cis-9,10-dihydrophenanthrenediamide ligands, cis-9,10-PhenH(2)(NR)(2)Ti(O(i)Pr)(2) [PhenH(2) = 9,10-dihydrophenanthrene, R = 2,6-(i)Pr(2)C(6)H(3) (2a), 2,6-Et(2)C(6)H(3) (2b), 2,6-Me(2)C(6)H(3) (2c)], cis-9,10-PhenH(2)(NR(1))(NR(2))Ti(O(i)Pr)(2) [R(1) = 2,6-(i)Pr(2)C(6)H(3), R(2) = 2,6-Et(2)C(6)H(3) (2d); R(1) = 2,6-(i)Pr(2)C(6)H(3), R(2) = 2,6-Me(2)C(6)H(3) (2e)], and [cis-9,10-PhenH(2)(NR(1))(2)][o-C(6)H(4)(CH=NR(2))]TiO(i)Pr [R(1) = 2,6-(i)Pr(2)C(6)H(3), R(2) = 2,6-Et(2)C(6)H(3) (3a); R(1) = 2,6-(i)Pr(2)C(6)H(3), 2,6-Me(2)C(6)H(3) (3b)], have been synthesized from the reactions of TiCl(2)(O(i)Pr)(2) with o-C(6)H(4)(CH=NR)Li [R = 2,6-(i)Pr(2)C(6)H(3), 2,6-Et(2)C(6)H(3), 2,6-Me(2)C(6)H(3)]. The symmetric complexes 2a-2c were obtained from the reactions of TiCl(2)(O(i)Pr)(2) with 2 equiv of the corresponding o-C(6)H(4)(CH=NR)Li followed by intramolecular C-C bond-forming reductive elimination and oxidative coupling processes, while the asymmetric complexes 2d-2e were formed from the reaction of TiCl(2)(O(i)Pr)(2) with two different types of o-C(6)H(4)(CH=NR)Li sequentially. The complexes 3a and 3b were also isolated from the reactions for complexes 2d and 2e. All complexes were characterized by (1)H and (13)C NMR spectroscopy, and the molecular structures of 2a, 2b, 2e, and 3a were determined by X-ray crystallography.

Following the Gould—Jacobs reaction, a series of 4-quinolinol-3-carboxylic acids (III) is prepared and investigated for their antioxidant properties in chemical and biological experiments.

Reactions of CrCl(2)(THF)(2) with N-aryl-9,10-iminophenanthraquinone in CH(2)Cl(2) give the monoimine chromium complexes (Ar)IPQCrCl(2)(THF)(2) (1, Ar = 2,6-Me(2)C(6)H(3); 2, Ar = 2,6-Et(2)C(6)H(3); 3, Ar = 2,6-(i)Pr(2)C(6)H(3)). Molecular structures of 1 and 3 were revealed to be monomeric with the chromium atoms in distorted octahedral geometries. Similar reactions of CrCl(2)(THF)(2) with N,N-bis(arylimino)phenanthrene ligands afford the diimine complexes (Ar1,Ar2)BIPCrCl(μ-Cl)(3)Cr(THF)(Ar1,Ar2)BIP (4, Ar(1) = Ar(2) = 2,6-Me(2)C(6)H(3); 5, Ar(1) = Ar(2) = 2,6-Et(2)C(6)H(3); 6, Ar(1) = Ar(2) = 2,6-(i)Pr(2)C(6)H(3); 7, Ar(1) = 2,6-Me(2)C(6)H(3), Ar(2) = 2,6-(i)Pr(2)C(6)H(3)). The X-ray diffraction analysis shows that 4, 5, and 7 are chlorine-bridged dimers with each chromium atom in a distorted octahedral geometry. Upon activation with MAO, all these complexes exhibit good catalytic activities for isoprene polymerization affording polyisoprene with predominantly a cis-1,4 unit.

The title compound, C(32)H(32)N(2), has crystallographic twofold rotation symmetry, with two C atoms lying on the rotation axis. The dihedral angle between the substituted benzene ring and the naphthalene ring system is 79.8 (1)°. The crystal structure is stabilized by C-H⋯N inter-actions, which form a chain motif along the b-axis direction.

The title dinuclear titanocene, [Ti(2)(C(8)H(9)O)(C(18)H(25)Si)(2)Cl(3)O], contains one Ti atom tetra-hedrally coordinated by two Cl atoms, a bridging O atom and the substituted cyclo-penta-dienyl ligand, and another Ti atom tetra-hedrally coordinated by a Cl atom, a bridging O atom, the 2,6-dimethyl-phenolate ligand and the substituted cyclo-penta-dienyl ligand. The bridging O atom lies on a twofold rotation axis.