手性亚砜法合成粉 虫性信息素

5-氯-2-戊酮(2)经四步反应制得(R)-(+)-4-甲基-3-戊烯基对甲苯基亚砜(6), 化合物6与乙醛进行不对称加成反应得手性醇(7), 7经兰尼镍还原性脱硫反应即合成出目标产物粉 虫性信息素(1), 其光学纯度可达45%。     

Synthesis and properties of poly(dipropargyl sulfoxide)

The preparation and cyclopolymerization of dipropargyl sulfoxide were studied. The polymerization of dipropargyl sulfoxide was carried out by various transition metal catalysts. WCl₆–EtAlCl₂, MoCl₅, and PdCl₂ catalyst systems were very effective. The resulting poly(dipropargyl sulfoxide) structures were characterized by NMR (¹H and ¹³C), IR, and elemental analysis to have conjugated polyene units. Poly(dipropargyl sulfoxide) prepared by PdCl₂ was mostly soluble in organic solvents such as DMF and DMSO. Thermal and oxidative properties of poly(dipropargyl sulfoxide) were also studied. The electrical conductivity of iodine-doped poly(dipropargyl sulfoxide) was 5.2 × 10^?2 Ω^?1 cm^?1. Comparisons of poly(dipropargyl sulfoxide) properties with other similar polymers from dipropargyl sulfur derivatives such as dipropargyl sulfide and dipropargyl sulfone were also carried out. © 1993 John Wiley & Sons, Inc.     

亚砜还原法合成聚苯醚硫醚的结构与性能研究

以氟苯和氯化亚砜反应合成了4,4’-二氟二苯亚砜,并将其与4,4’二羟基二苯硫醚在N-甲基吡咯烷酮溶剂中进行亲核取代反应合成了聚苯醚硫醚醚亚砜,用乙二酰氯/四丁基碘化铵还原该亚砜聚合物制备了聚苯醚硫醚。用红外光谱和核磁共振谱对合成单体的结构进行了确认,同时对聚合物进行了红外光谱、核磁共振、元素分析、X射线光电子能谱、X射线衍射、DSC分析、TG/DTG以及溶解性测试。结果表明聚苯醚硫醚样品具有氧醚和硫醚交替的线性结构,特性粘度为0.55 dL/g的PPSE熔点达236℃,在氮气条件下,样品起始分解温度和最大分解速率处温度分别为359℃和514℃,在700℃时的重量保留率为43.3%,且在加热条件下能溶解于N-甲基吡咯烷酮(NMP)、二甲基乙酰胺(DMAc)、二甲基甲酰胺(DMF)等极性有机溶剂中。     

Synthesis of polyacetylene with titanocene-aluminum hydride catalysts

Heterometallic hydride titanocene-aluminum complexes Cp₂Ti(-H)₂AlH(X) and (Cp₂Ti)₂AlH₄X are highly efficient homogeneous catalysts for acetylene polymerization. The binuclear complex of the composition Cp₂Ti(-H)₂AlH₂ at 2.2–3.2M concentrations in ether-toluene solutions exhibits the maximum activity in this reaction. It is believed that the mechanisms of the isomerization of olefins and the polymerization of acetylene are similar and, correspondingly, the compositions and structures of the active sites in both processes are close to each other. The polyacetylene formed with hydride catalysts (mostly thecis-isomer) after doping with iodine has an electrical conductivity of 1.5–2.0 · 10⁴ Ohm^–1 cm^–1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 405–409, March, 1994.The work was carried out with the financial support of the Russian Foundation for Basic Research, project No. 93-03-5757.     

Synthesis of graft copolymer by ATRP of MMA from poly(phenylacetylene)

The present report describes the synthesis of a densely grafted copolymer consisting of a rigid main chain and flexible side chains by the atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) from an ATRP initiator‐bearing poly(phenylacetylene) [poly(BrPA)]. Poly(BrPA) was obtained by the polymerization of 4‐ethynylbenzyl‐2‐bromoisobutyrate using [Rh(NBD)Cl]₂ in the presence of Et₃N. The ¹H NMR spectrum showed that poly(BrPA) was in the cis‐transoid form. Upon heating at 30 °C for 24 h the cis‐transoid form was maintained. ATRP of MMA from the poly(BrPA) was carried out at 30 °C using CuX (X = Br, Cl) as the catalyst and N,N,N′,N′,N′‐pentamethyldiethylenetriamine as the ligand, and the resulting graft copolymers were investigated with ¹H NMR and SEC. To analyze the graft structure in more detail, the graft copolymers were hydrolyzed with KOH and the resultant poly(MMA) part was investigated with ¹H NMR and SEC. The polydispersity indexes of 1.25–1.45 indicated that the graft copolymers have well‐controlled side chains. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6697–6707, 2006     

互穿网络高吸水树脂IPN的合成

采用溶液聚合制备了聚乙烯醇(PVA)和部分中和的丙烯酸-丙烯酰胺共聚物复合的互穿网络高吸水树脂(IPN)。通过正交实验研究了单体浓度,交联剂用量对IPN吸水率的影响。PVA的加入能有效提高IPN的吸水能力。在较适宜的反应条件下,IPN吸蒸馏水量达1481倍,吸0.9%NaCl溶液为130倍。     

原子转移自由基悬浮聚合制备PVC-g-PMMA共聚物

原子转移自由基悬浮聚合制备PVC-g-PMMA共聚物;聚氯乙稀;甲基丙烯酸甲酯;原子转移自由基悬浮聚合     

Investigation at the chain segmental level of the miscibility of poly(vinyl chloride)/atactic poly(methyl methacrylate) blends

We employed high‐resolution ¹³C cross‐polarization/magic‐angle‐spinning/dipolar‐decoupling NMR spectroscopy to investigate the miscibility and phase behavior of poly(vinyl chloride) (PVC)/poly(methyl methacrylate) (PMMA) blends. The spin–lattice relaxation times of protons in both the laboratory and rotating frames [T₁(H) and T_1ρ(H), respectively] were indirectly measured through ¹³C resonances. The T₁(H) results indicate that the blends are homogeneous, at least on a scale of 200–300 Å, confirming the miscibility of the system from a differential scanning calorimetry study in terms of the replacement of the glass‐transition‐temperature feature. The single decay and composition‐dependent T_1ρ(H) values for each blend further demonstrate that the spin diffusion among all protons in the blends averages out the whole relaxation process; therefore, the blends are homogeneous on a scale of 18–20 Å. The microcrystallinity of PVC disappears upon blending with PMMA, indicating intimate mixing of the two polymers. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2390–2396, 2001     

Synthesis and structural studies of a bis(carbamoyl methyl) sulfoxide complex of uranyl nitrate

A new tri-functional ligand ⁱBu₂NCOCH₂SOCH₂CONⁱBu₂ was prepared and characterized. The coordination chemistry of this ligand with uranyl nitrate was studied with IR, ¹H NMR, electrospray mass–spectrometry, thermogravimetry, and elemental analysis. The structure of [UO₂(NO₃)₂(ⁱBu₂NCOCH₂SOCH₂CONⁱBu₂)] was determined by single-crystal X-ray diffraction. The uranium(VI) ion is surrounded by eight oxygens in a hexagonal bipyramidal geometry. Four oxygens from two nitrates and two oxygens from the ligand form a planar hexagon. The ligand is a bidentate chelate, bonding through sulfoxo and one of the carbamoyl groups to uranyl nitrate.     

Synthesis and spectroscopic characterization of new metal(II) complexes with methionine sulfoxide

Methionine sulfoxide complexes of iron(II) and copper(II) were synthesized and characterized by chemical and spectroscopic techniques. Elemental and atomic absorption analyses fit the compositions K₂[Fe(metSO)₂]SO₄·H₂O and [Cu(metSO)₂]·H₂O. Electronic absorption spectra of the complexes are typical of octahedral geometries. Infrared spectroscopy suggests coordination of the ligand to the metal through the carboxylate and sulfoxide groups. An EPR spectrum of the Cu(II) complex indicates tetragonal distortion of its octahedral symmetry. ⁵⁷Fe Mössbauer parameters are also consistent with octahedral stereochemistry for the iron(II) complex. The complexes are very soluble in water.     

聚甲基丙烯酸甲酯与聚醋酸乙烯酯共混的红外光谱研究

用红外光谱(FTIR)研究了聚甲基丙烯酸甲酯(PMMA)与聚醋酸乙烯酯(PVAc)共混体系相容性,在160℃以上共混体系发生相分离;分相体系与非分相体系的FTIR谱明显不同;共混体系的FTIR谱不能从两统组分红外光谱简单加和得到;结果表明大分子构象发生了变化,PMMA/PVAc体系相容可能是大分子构象熵变所致。     

Sulfurization of polymers. 6. Poly(vinylene polysulfide), poly(thienothiophene), and related structures from polyacetylene and elemental sulfur

Polyacetylene obtained by the dehydrochlorination of polyvinyl chloride in the NaOH—DMSO system undergoes sulfurization with elemental sulfur at 120—300 °C to liberate hydrogen sulfide and to form electroconducting (0.7·10^–12—5.8·10^–15Sm nm^–1) and paramagnetic (1.5·10¹⁷—1.7·10¹⁹sp g^–1, g = 2.0035—2.0045, H= 0.44—0.66 mT) dark powders with a metallic luster. Their IR spectra and comparison with the samples of sulfurized polyethylene show that sulfurized polyacetylene contains poly(vinylene polysulfide), poly(thienothiophene), and related structures. The polymers afford the cathode discharge capacity of lithium batteries up to 950 mA h g^–1(in the first cycle) and stable cycling at a level of 500—300 mA h g^–1(25 cycles).     

Synthesis and characterization of ran-copoly (p-phenylene sulfide sulfone/ketone)s

Random copoly(p-phenylene sulfide sulfone/ketone)s (PPSS/K) are prepared in high yield by the polycondensation of sodium hydrosulfide (NaSH) with bis(4-chlorophenyl) sulfone (BCPS) and 4,4′-dichlorobenzophenone (DCBP). The polymerization is conducted between 200–220°C, depending on the composition of the copolymer, and in the presence of water without any detrimental effects to the molecular weight. The copolymers with sulfone/ketone mole ratios (S : K) > 25 : 75 are amorphous, while the copolymers with S : K ratios ≤ 25 : 75 are crystalline. These materials form tough, creaseable films and exhibit a linear increase in the glass transition temperature with increasing sulfone content. Sulfuric acid solutions of the copolymers are dark orange to red and display an increasing λ_max in the uv-visible spectra as the S:K ratio of the copolymers decreases. © 1994 John Wiley & Sons, Inc.     

Preparation and properties of poly(alkyl vinyl ether-2-ethyl-2-oxazoline) diblock copolymers

A method for the synthesis of well-defined poly(alkyl vinyl ether–2-ethyl-2-oxazoline) diblock copolymers with hydrolytically stable block linkages has been developed. Monofunctional poly(alkyl vinyl ether) oligomers with nearly Poisson molecular weight distributions were prepared via a living cationic polymerization method using chloroethyl vinyl ether together with HI/ZnI₂ as the initiating system and lithium borohydride as the termination reagent. Using the resultant chloroethyl ether functional oligomers in combination with sodium iodide as macroinitiators, 2-ethyl-2-oxazoline was polymerized in chlorobenzene/NMP to afford diblock copolymers. A series of poly(methyl vinyl ether–2-ethyl-2-oxazoline) diblock materials were found to have polydispersities of ≈ 1.3–1.4 and are microphase separated as indicated by two T_g's in their DSC thermograms. These copolymers are presently being used as model materials to study fundamental parameters important for steric stabilization of dispersions in polar media. © 1993 John Wiley & Sons, Inc.     

STUDIES OF A.C. CONDUCTIVITY OF POLY(VINYL BORATE) AND ITS CALCIUM DERIVATIVE IN SOLID STATE

An attempt has been made in the present work to prepare poly(vinyl borate),PVBO and its calcium derivative by homogeneous esterification of PVA with boric acid in non-aqueous medium in the presence of a catalyst ethyl nitrate dimethyl sulfoxide.The compounds were characterized by IR and ~1H-NMR spectra.Conductivities were determined from 30℃to 90℃in solid state within a frequency range of 42 Hz to 100 kHz.The compounds so formed showed ionic conductivity and their conductivities were dependent on frequen...     

Interactions and prediction of phase diagrams in ternary blends comprising poly(vinyl acetate), poly(vinyl p‐phenol), and poly(methyl methacrylate)

This study investigated and discovered a new miscible ternary blend system comprising three amorphous polymers: poly(vinyl acetate) (PVAc), poly(vinyl p‐phenol) (PVPh), and poly(methyl methacrylate) (PMMA) using thermal analysis and optical and scanning electron microscopies. The ternary compositions are largely miscible except for a small region of borderline ternary miscibility near the side, where the binary blends of PVAc/PMMA are originally of a borderline miscibility with broad T_g. In addition to the discovering miscibility in a new ternary blend, another objective of this study was to investigate whether the introduction of a third polymer component (PVPh) with hydrogen bonding capacity might disrupt or enhance the metastable miscibility between PVAc and PMMA. The PVPh component does not seem to exert any “bridging effect” to bring the mixture of PVAc and PMMA to a better state of miscibility; neither does the Δχ effect seem to disrupt the borderline miscible PVAc/PMMA blend into a phase‐separated system by introducing PVPh. Apparently, the ternary is able to remain in as a miscible state as the binary systems owing to the fact that PVPh is capable of maintaining roughly equal H‐bonding interactions with either PVAc or PMMA in the ternary mixtures to maintain balanced interactions among the ternary mixtures. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1147–1160, 2006     

Synthesis and properties of poly(oxyethylene)s containing thioether,sulfoxide, or sulfone groups

Poly[oxy(ethylthiomethyl)ethylene] (ETE) was prepared from poly[oxy (chloromethyl)ethylene] (CE) by reaction with sodium ethanethiolate. Sulfoxide and sulfone analogues were synthesized by oxidation of the poly[oxy(ethylthiomethyl)ethylene]. By changing the chloromethyl/sodium ethanethiolate ratio, poly[oxy (chloromethyl)ethylene-co-oxy(ethylthiomethyl)ethylene] (CE-ETEs) were easily made. Poly[oxy(ethylsulfinylmethyl)ethylene] (ESXE), poly[oxy(chloromethyl)ethylene-co-oxy(ethylsulfinylmethyl)ethylene] (CE-ESXEs), poly[oxy(ethylsulfonylmethyl)ethylene] (ESE), and poly[oxy(chloromethyl)ethylene-co-oxy(ethylsulfonylmethyl)ethylene] (CE-ESEs) were obtained by oxidation of ETE or CE-ETEs. There was little if any chain degradation. The (co)polymer structures were confirmed by FTIR and ¹H-NMR spectroscopic studies. Their thermal properties were studied by DSC and TGA. T_gs of ETE, ESXE, and ESE were -57, 36, and 57°C, respectively, and T_d,os (initial decomposition temperature, TGA) were 331, 198, and 308°C, respectively. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 793–801, 1998     

Application of Ultrasonic Attenuation Measurements in the Studies on Macromolecular Conformational Behaviors

——Phase Behavior of the Aqueous Solution of Poly(vinyl methyl ether) Sensitive to Temperature and the Modification of the Behavior by Using Poly(acrylic acid) The phase behavior of the aqueous solution of poly(vinyl methyl ether) (PVME) sensitive to temperature and the modification of the behavior by using poly(acrylic acid) (PAA) have been studied by ultrasonic attenuation measurements and fluorescence probe techniques. It has been observed that PVME solution is transparent at room temperature and becomes turbid upon heating. The solution turns clear again as soon as the temperature is decreased to room temperature. The heating and cooling process can be repeated for many times. The phase behavior of the solution sensitive to temperature is attributed to the conformational changes of the polymer. PVME may adopt an open coil conformation at room temperature. With this conformation, the polymer is well miscible with the solvent, water, and thereby the system is a real solution. The polymer may adopt a compact coil conformation when the temperature is higher than a specific value, which is called the LCST (the lower critical solution temperature) of PVME. In this case, the polymer tangles to each other and forms various aggregates, which can scatter incident light and ultrasonic waves greatly, resulting in the phase separation. Introduction of PAA decreases the temperature sensitivity of the phase behavior of the polymer. The nature of the inhibition is attributed to the complexation of PAA with PVME and the strong hydrophilicity of PAA. Results from fluorescence probe studies are in accordance with those from ultrasonic attenuation measurements, indicating again that the ultrasonic attenuation method can be successfully used for the qualitative studies of polymer conformations and complexation between polymers.     

Synthesis and properties of an ionic polyacetylene with aromatic heterocycles

A new ionic polyacetylene with two aromatic heterocycles (pyridyl and thienyl) was prepared by the activation polymerization of 2‐ethynylpyridine by using 3‐(6‐bromohexyloxy)methylthiophene without any additional initiator or catalyst. The activated acetylenic triple bond of N‐substituted‐2‐ethynylpyridinium bromide, formed at first quaternarization process, was susceptible to linear polymerization. The instrumental analysis data on the polymer structure revealed that the polymer have the conjugated polyene backbone structure with the designed two aromatic heterocycles. The photoluminescence peak is located at 510 nm corresponding to a photon energy of 2.43eV. The electrochemical properties of this ionic polyacetylene were also measured and discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5679–5685, 2007