CONFORMATIONAL INVESTIGATION OF SOME SYMMETRICALLY SUBSTITUTED DIALKYL MONO-SULFIDES AND DISULFIDES BY IR SPECTROSCOPY

Abstract

Several infrared and Raman studies have been performed on compounds containing the disulfide group in the region of C-S and S-S stretching modes (1–4) in order to get a better insight of the correlations between molecular conformation and peculiar geometry parameters of the dihedral angle CS-SC.     

THE CRYSTALLIZATION BEHAVIOR OF URETHANE SUBSTITUTED POLYDIACETYLENE

The crystalline behavior of urethane substitute polydiacetylene was studied by using pohrized light and electron microscopy. The lamellar morphological structure was observed in the crystallized films. The thickness of lamellae is about 300A, being independent of the crystalline temperature. But the size and density of lamellae were dependent on the crystallization temperature. If the molten film was sheared during the crystallzation process the oriented lamellae grew with their long axes perpendicular to the direction of shear and the chain direction was normal to the lamellar surface.     

THE EFFECT OF MIXED MICELLES OF SURFACTANTS ON THE ALKALINE HYDROLYSIS OF ESTERS

The alkaline hydrolysis of aromatic and normal aliphatic acid esters have been studied at 25°C In mixed micellar solution of surfactants (Brij35—SDS, Brij35 — DTAB, Brij35—TTAB.Brij35-CTAB. Triton X—100 —CTAB, Triton X— 100 —SDS) with UV spectrophotometry and the method of thermokinetics The critical mice liar concentrations of the corresponding systems have also been measured with UV spectrophotometry in this paper. K_jnln micellar pseudo-phase has been calculated- The ratios of ki.to ki.for all mixed micellar systems Investigated are less than 1. The results indicate that these reactions are inhibited by the mixed micelles and the mixed micelles exhibit a greater effect of Inhibition on the reactions than those do In corresponding single ones. The reason for this is that the micropolarity of the compact Stern layer of mixed micelle is lower, and the micro viscidity Is higher. The Inhibition effect! also depend on the hydrophobic chain length of the surfactants and the hydrophobicity of the substrate.     

吐温-80对固定化脂肪酶催化酮基布洛芬氯乙酯对映体选择性水解反应的影响

酮基布洛芬为2-芳基丙酸类非甾体抗炎药的一种,其药效与立体构型有很大关系[1].生物法催化的动力学拆分是获得单一对映体酮基布洛芬的有效方法之一[2,3].最近,我们发现在利用皱褶假丝酵母(Candida rugosa)脂肪酶Lipase OF催化拆分酮基布洛芬氯乙酯时,向反应体系中加入非离子表面活性剂吐温-80,不仅可大幅度提高反应速度,而且更重要的是解决了原来Lipase OF选择性较差的问题,从而为酮基布洛芬的对映体拆分提供了一种新方法.     

PRODUCTS OF THE ALKALINE HYDROLYSIS OF S-CHLOROMETHYL AND S-(N-ETHOXYCARBONYL-N-METHYLCARBAMOYLMETHYL) O,O-DIETHYL PHOSPHORODITHIOATE

Abstract

The alkaline hydrolysis of S-chloromethyl O,O-diethyl phosphorodithioate (chlormephos) and of S-(N-ethoxycarbonyl-N-methylcarbamoylmethyl) O,O-diethyl phosphorodithioate (mecarbam) may involve attack by hydroxide ion at phosphorus with phosphorus-sulfur cleavage, at the substituted S-methyl carbon atom with sulfur-carbon cleavage or, in the case of mecarbam. at the carbonyl carbon atom with carbonyl-nitrogen cleavage. Further reaction of the initially-formed O,O-diethyl hydrogen phosphorodithioate with chlormephos may lead to the formation of additional products.     

活性炭纤维对氙的动态吸附性能研究

采用动态吸附实验装置，研究了吸附温度、原料气浓度和原料气流量对活性炭纤维动态吸附氙性能的影响。结果表明：在低温条件下（≤273K)，随着温度的升高，活性炭纤维对氙的平衡吸附量明显下降／同时，活性炭纤维对氙的平衡吸附量分别随着原料气浓度及原料气流量的增大而增大。     

螺旋构象的微环境效应——7.二甲基亚砜-水二元溶剂的组成对糖淀粉催化或抑制酯水解行为的影响

我们在研究Me_2SO—H_2O二元体系中糖淀粉[A]的物理和化学行为的基础上,又就溶剂组成对十二酸对-硝基苯酚酯水解行为的影响进行了研究。我们测量了硼酸缓冲液体系中五个不同φ值的k_(obs)对糖淀粉浓度的依赖关系(图1),φ值为混合溶剂中Me_2SO的体积分数~([1])。初看起来结果是复杂的,在[A]=0,即糖淀粉不存在的情况下,速度常数(k_(nn))随溶剂中Me_2SO量的增加而增加,即φ=0.5<0.6<0.7<0.8<0.9。加入糖淀粉后,曲线开始互相交叉。φ[A]>1.1×10~(-4)时,其次序几乎发生倒转,即φ=0.9<0.8<0.7<0.5<0.6。而且,=0.5,0.6,0.7的曲线随[A]增大而下     

沥青基球状活性炭气相吸脱附行为研究

本文利用热重法研究了一系列沥青基球状活性炭对蒸汽及正已烷蒸汽的动态吸脱附曲线。结果表明,PSAC对苯蒸汽的吸附及再生性能优良。随吸附温度的降低、比表面积的增大、总孔容及微孔容的增大,PSAC对苯蒸汽的吸附容量增大。PSAC对正已烷的吸附速度大于对苯蒸汽的吸附速度,但其对正已烷的平衡吸附容量小于对苯蒸汽的平衡吸附容量。     

DYNAMIC PROCESS OF VALENCE CHANGE OF EUROPIUM ION IN EUROPIUM DIFLUORIDE AT HIGH TEMPERATURE

The dynamic process of the ionic valence changing from Eu~(2+) to Eu~(3+) in EuF_2 at high temperature has been investigated by ESCA, high,temperature X-ray diffraction, high temperature spectrum, high temperature magnetic Isusceptibility and Mssbauer spectrum. It has been shown that the formed Eu~(3+) exists in different compounds when EuF_2 is heated to high temperature in different atmospheres. In air, Eu~(3+) exists in the form of hexagonal EuOF, in nitrogen, in the form of orthogonal EuF_3 and non-hexagon EuOF. This is because decomposition or disproportionation of EuF_2 is different with different atmospheres. The magnetic susceptibility measurement showed quantitatively that the change rate from Eu~(2+) to Eu~(3+) is about 95% in air, and about 75% in nitrogen when it is heated to 900℃. A small amount of Eu~(2+) coexists with Eu~(3+) in the final product.     

APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

A use of sulfonate ester as a linker in synthesis of w-aminoalkanols was reporte.Diols were tethered onto polystyryl sulfonyl chloride resin,yielding sulfonate resins(2).After cleaved by diethyl amine,diisopropylamine and propylamine respectively,three w-aminoalkanlos were obtained.     

NEW DERIVATIVES OF 4,5-BENZO-1,3,2-OXAZA (OR D1AZA)-PHOSPHOLANE FROM CONVENIENT CONDENSATION OF SUBSTITUTED UREA WITH TRIS(DIALKYLAMINO)PHOSPHINE

Abstract

The condensation of N-phenyl-N′-(2-hydroxylphenyl)urea or N-phenyl-N′-(2-aminophenyl)urea with tris(dia1kylamino)phosphine afforded derivatives of 4,5-benzo-1,3,2-oxaza (or diaza)-phospholane which formed intramolecular hydrogen bond. The cleavage of the amide bond to give N,N-dialky1-N′-phenylurea together with polymers of 1,3,2-benzodiazaphosphole was observed in the latter reaction.     

DYNAMIC PROPERTIES OF MAIN SOUNDER IN BLACK CICADA (C. atrata Fabricius)~*

In this paper, the dynamic properties of the main sounder (the sounding muscle (SMc) and the sounding membrane (SM)) and the generating mechanism of amplitude-modulation pulse train (AMPT) are given. The acting process of SMc is a quasi-simple harmonic contraction vibration. The amplitudes of soundless and sounding contracting motion are about 17.2 /μm and 29.4/μm, respectively, and the efficiency of dynamic sounding is about 17％, The unsounded motion of SM is a quasi-simple harmonic vibration, and the amplitude is about 7.81/μm. The sounding motion of SM is a complex vibration, and the amplitude is about 12.66 μm. In each syllable of the song, AMPT_(1,2,3) are separately produced by driving vibrations (V_1,2,3)) of three long ribs in the upper half of SM, and the peaks of V_(1,2,3) lead the first pulse of high amplitude in AMPT_(1,2,3) by 0.156 ms, respectively. The membrane structure in the lower half of SM is mainly to transmit contracting movement of SMc.     

dppm与CH2Cl2在Pd（OAc）2作用下反应stopped—flow动态学研究

ｄｐｐｍ与ＣＨ２Ｃｌ２在Ｐｄ（ＯＡｃ）２作用下反应ｓｔｏｐｐｅｄ＿ｆｌｏｗ动态学研究韦凤萍黄永仁（华东师范大学分析测试中心上海２０００６１）汪汉卿（中国科学院物理研究所兰州７３００００关键词动态学Ｐｄ（ＯＡｃ）２ｄｐｐｍＣＨ２Ｃｌ２停－流中图分类号Ｏ...     

固定床中树脂催化油脂副产物制备生物柴油

以棕榈油脱臭馏出物(PFAD)和无水乙醇为原料,强酸性阳离子交换树脂为固体酸催化剂,在自制的固定床反应器中进行酯化反应,成功合成了脂肪酸乙酯(生物柴油).固定床反应器尺寸为φ1.62 cm×72.7 cm.结果表明,酯化反应的最佳物料比为n(乙醇)/n(PFAD)=13.2;反应温度在乙醇正常沸点783℃以下时,反应温度越高,酯化率越大;酯化率随催化接触时间增大而增大,但增大速度逐渐趋缓.当在常压下,75℃反应55min时,脂肪酸乙酯的一次转化率可达76%左右.     

固定床中树脂催化油脂副产物制备生物柴油

以棕榈油脱臭馏出物(PFAD)和无水乙醇为原料,强酸性阳离子交换树脂为固体酸催化剂,在自制的固定床反应器中进行酯化反应,成功合成了脂肪酸乙酯(生物柴油).固定床反应器尺寸为Φ1.62cm×72.7cm.结果表明,酯化反应的最佳物料比为n(乙醇)/n(PFAD)=13.2;反应温度在乙醇正常沸点78.3℃以下时,反应温度越高,酯化率越大;酯化率随催化接触时间增大而增大,但增大速度逐渐趋缓.当在常压下,75℃反应55min时,脂肪酸乙酯的一次转化率可迭76%左右.     

聚马来松香乙二醇酯Cu(Ⅱ)配合物固定化漆树漆酶的研究

制备了聚马来松香乙二醇酯(MEEP)Cu2 、Ni2 、Ca2 和Mg2 金属离子配合物,并分别以4种配合物为载体固定化漆树漆酶,初步探讨了反应时间对酶固定化的影响,考察了固定化酶的性质.实验结果表明,在反应温度为25℃条件下,漆树漆酶的最佳固定化时间为16h;MEEPCu2 配合物固定化酶的固定化结果较好,重复使用6次后,酶相对保留活力为55.0%;该固定化酶的最适作用温度为40℃,pH值范围为5.89～9.23,固定化漆树漆酶具有比游离酶更好的热稳定性和更广泛的pH值适用范围.     

聚马来松香乙二醇酯Cu(II)配合物固定化漆树漆酶的研究

制备了聚马来松香乙二醇酯(MEEP)Cu2 、Ni2 、Ca2 和Mg2 金属离子配合物,并分别以4种配合物为载体固定化漆树漆酶,初步探讨了反应时间对酶固定化的影响,考察了固定化酶的性质。实验结果表明,在反应温度为25℃条件下,漆树漆酶的最佳固定化时间为16h;MEEPCu2 配合物固定化酶的固定化结果较好,重复使用6次后,酶相对保留活力为55.0%;该固定化酶的最适作用温度为40℃,pH值范围为5.89~9.23,固定化漆树漆酶具有比游离酶更好的热稳定性和更广泛的pH值适用范围。     

ORGANIC PHOSPHORUS COMPOUNDS 90.l A CONVENIENT,ONE-STEP SYNTHESIS OF ALKYL- AND ARYLPHOSPHONYL DICHLORIDES

Abstract

N,N-Disubstituted formamides such as dimethylformamide. N-formylpyrrolidine, N-formylpiperidine etc. and also pyridine and hexamethylphosphonic acid triamide catalyze the chlorination of phosphonates with thionyl chloride to give phosphonyl dichlorides in high yield. Thus RP(O)CI₂, R ? CH₃, C₂H₅, n-C₁₂H₂₅, C₆H₅, have been isolated in better than 90 per cent yield. The procedure is less satisfactory for the production of 2-chloroethylphosphonyl dichloride. Only a 34 per cent yield was realized.

The chlorination proceeds very likely through the intermediate formation of the halfesters, RP(O)(OR)CI since these could be isolated under favorable circumstances.     

APPLICATION OF THE SULFONATE ESTER GROUP AS A LINKER FOR SOLID PHASE ORGANIC SYNTHESIS

1. INTRODUCTIONIn recent years, solid phase organic synthesis (SPOS) has been increasingly used in the synthesis of small organic molecules [1]. The rapid development of SPOS brings with it the need for expanding a variety of linkers in order to accommodate new synthesis methods[2], and especially in the case of combinatorial chemistry, to allow additional diversity elements.Recently, Rueter and coworkers reported the use of a sulfonate ester as a linker in SPOS [3,4] and the compati…