Pt(II) ASSISTED DEOXYGENATION OF COORDINATED SULFOXIDES BY HYDROCHLORIC- OR HYDROBROMIC ACID

Abstract

The interaction of the complexes (Et₄ N)[Pt(R₂ SO)X₃] (R = Me, Et, CH₂ Ph, X [dbnd] C1; R [dbnd] Me, X [dbnd] Br) and cis-[Pt(Me₂ SO)₂ Cl₂] with concentrated HX (X [dbnd] Cl. Br) results in the reduction of the coordinated sulfoxides and oxidation of Pt(II) to Pt(IV). As a result [Pt(R₂ S)X₅ and [Pt(R₂S)₂ X₄] are formed. Ligands R₂ S can be removed from the complexes and isolated in a free state.     

THE REACTION OF ANHYDROUS HCI/CHLOROFORM WITH DIARYL SULFOXIDES

Abstract

The reaction of variously substituted diaryl sulfoxides with anhydrous HCl in chloroform was examined. The products ranged from the corresponding sulfides to mono- and dichlorinated sulfides and sulfoxides. The same reaction in the presence of phenol afforded primarily the corresponding sulfides accompanied by o- and p-chlorophenol. The latter reaction is an efficient means for deoxygenating diaryl sulfoxides. The mechanism of the reaction and the nature of the chlorinating species are discussed.     

OCCURRENCE OF LIGAND COUPLING IN THE REACTIONS OF VARIOUS SULFOXIDES WITH GRIGNARD REAGENTS

Abstract

Ligand coupling reactions take place not only between benzyl and 2-pyridyl groups and two 2-pyridyl groups in the treatment of benzyl, alkyl and aryl 2-pyridyl sulfoxides with Grignard reagents, but also between such groups as p-benzenesulfonylphenyl, 4-pyridyl, 2-quinolyl and 2-pyrimidyl, and the benzyl group. There are cases in which ligand exchange precedes ligand coupling, especially with 2-heteroaryl groups. In addition, even some alkyl groups were found to couple with the 2-pyridyl group. The ease of coupling seems to be associated with the electronegativity of the coupling carbon atom of the ligand, when one compares the ¹³C NMR chemical shifts.     

ASYMMETRIC REDUCTION OF CHIRAL SULFOXIDES BY OPTICALLY ACTIVE LITHIUM ALUMINUM HYDRIDE COMPLEXES WITH ALCOHOLS

Abstract

Optically active sulfoxides of low optical purity have been obtained by partial reduction of racemic sulfoxides using optically active lithium aluminum hydride-alcohol complexes as reducing agents. The steric course of the asymmetric reductions was found to be dependent on the composition of the complexes and on the configurations of optically active alcohols used. No configurational relationship between chirality at the sulfur and carbon atoms was observed.     

含硫醚结构均苯型聚酰亚胺的合成及表征

以4,4′-二氨基二苯硫醚(SDA)和均苯四酸酐(PMDA)为原料,通过溶液缩聚法-热酰亚胺/化学酰亚胺化的方法制备了一种含硫醚结构均苯型聚酰亚胺.利用高级旋转流变仪建立了在线跟踪反应进程的方法,采用热失重分析仪研究反应条件对热酰亚胺化及化学酰亚胺化法的影响,这些方法的建立为进一步制备高性能的聚酰亚胺提供有效的实验手段.采用小角激光光散射法、红外光谱、元素分析、接触角仪、DSC等方法对聚合物的结构与性能进行表征.结果显示,硫醚结构的引入,可有效改善聚合物薄膜的表面性能,其与铜箔之间的粘附功明显大于传统聚酰亚胺,在无胶挠性线路板应用方面显示出较好的应用前景.所获聚合物的Mw为(6.7±1.6)×104,分解温度均高于560℃;DSC的结果显示所制备的两种酰亚胺化聚合物均具有较高的玻璃化转变温度,相比之下,化学酰亚胺化更有利于获得高酰亚胺化程度的聚合物,产物的玻璃化转变温度也更高.     

KINETICS AND MECHANISM OF THE THERMOLYSIS OF SULFOXIDES

Abstract

The thermolysis of sulfoxides possessing β-hydrogen atoms is a versatile and mild method to prepare olefins. The reaction is generally accepted to proceed via a concerted mechanism. Accordingly, solvent effects are not large, and appear to be associated with the initial states. The reverse process has been documented for R = t-Bu; MeSOH or PhSOH can also be employed.     

SYNTHESIS OF CHIRAL SULFOXIDES BY ASYMMETRIC OXIDATION

Abstract

The main chemical or enzymatic methods of asymmetric oxidation of sulfides are reviewed. A new approach to chiral sulfoxides is described, which uses tertiobutyl hydroperoxide in presence of a chiral titanium complex. The results obtained during the last two years are summarized. The best enantiomeric excess amounts to 95% in the case of formation of cyclopropyl phenyl sulfoxide.     

葡萄糖酸根插层水滑石的制备、表征及对硼的吸附研究

采用离子交换法制备出了葡萄糖酸根插层的类水滑石,并对其进行了XRD、FT-IR、TG等表征。将这一新型吸附剂应用于吸附溶液中的硼,并对影响其吸附容量的条件进行了实验研究。结果表明,该吸附剂比MgAl-NO3--LDH对硼有较高的吸附容量,且吸附容量随着接触时间的延长而增大,随硼浓度的增大而增大,随着pH的增加而增大,随着氯离子浓度的增大而减小。     

MICROWAVE-CATALYZED REACTION OF NORBORNANE OXIDE WITH (CHLOROMETHYL) METHYL SULFIDE

Microwave-catalyzed reaction of (chloromethyl) methyl sulfide with exo-norbornane oxide furnishes fourteen compounds. The probable mechanism of their formation and their mass spectral characterization are presented in this communication.     

聚苯硫醚及其聚砜共混物的结晶形态研究

应用偏光显微镜、扫描电子显微镜及蚀刻的方法,研究了聚苯硫醚及其与聚砜共混物的结晶形态与织构。结果表明,经固相空气热处理的聚苯硫醚,其本体与表面区域的结晶形态有显著的不同;蚀刻择优发生于球晶的晶界上;随着聚砜组份的增加,共混物的织构从聚苯硫醚为连续相逐渐转变为聚砜为连续相,聚苯硫醚的球晶形态也逐渐变得不规整。     

聚苯硫醚及其聚醚砜共混物结晶形态的研究

本文借用偏光显微镜(PLM)、扫描电子显微镜(SEM)、小角激光光散射仪(SALS)及蚀刻的方法,研完了聚苯硫醚及其与聚醚砜共混物的结晶形态和织构,讨论了共混方法及其共混组成对其共混物的结晶形态的影响。结果表明,聚苯硫醚在应力作用下能生成横晶;溶液共混物和粉末机械共混物呈现不同的共混结晶形态;随着聚醚砜组分的增加,共混物的织构从聚苯硫醚为连续相逐渐转变为聚醚砜为连续相,同时,聚醚砜的聚集区域从分散在聚苯硫醚的球晶之间转变为聚集在聚苯硫醚的球晶内,使聚苯硫醚的球晶形态逐渐变得不规整。     

HIGH TEMPERATURE REACTIONS OF HYDROGEN SULFIDE AND THIOLS WITH ORGANIC COMPOUNDS

Abstract

The high temperature reaction of hydrogen sulfide with chloro- and bromosubstituted aromatic and heteroaromatic compounds is a convenient method for synthesis of the corresponding thiols and sulfides. The reaction of hydrogen sulfide with ortho-dihalosubstituted aromatic compounds may be directed toward the formation of thianthrene or dibenzo thiophene and their derivatives. The high temperature reaction of thiophenol with chloro- and bromoderivatives of aromatic and heteroaromatic compounds affords the corresponding mixed sulfides. The reaction with ortho-substituted halogen derivatives leads to formation of the sulfur heterocycles of the thianthrene, thioxanthene and dibenzothiophenene series.

The high temperature reaction of hydrogen sulfide with vinyl chloride gives vinylthiol and thiophene. Hydrogen sulfide initiates pyrolytic transformations of thiophene, aniline and benzaldehyde into dithienyls, 5.10-dihydrophenazine and stilbene, respectively. The reaction mechanism has been discussed.     

聚苯硫醚/尼龙6共混物界面对结晶行为的影响

高分子作为材料时 ,其力学性能受其结晶形态的影响 ,而其结晶形态与其结晶行为有关 .结晶性聚合物共混物中结晶组分由于第二组分存在 ,改变了结晶组分在熔体时的化学与物理环境 .因此 ,其结晶组分的结晶行为不仅取决于两组分在熔体时的相容性 ,而且与第二组分是否起到异相晶核作用和 /或两组分间界面是否诱导成核作用有关 ,从而影响共混物中结晶组分的结晶行为 ,导致共混物力学性能的改变[1～ 4] .在ＰＰＳ/ＰＡ6共混物中 ,由于ＰＰＳ的熔点和熔体结晶温度都比ＰＡ6的高 ,共混物熔体降温结晶ＰＰＳ是在ＰＡ6熔体存在下发生结晶 ,而ＰＡ6是在…     

CHEMOSELECTIVE REDUCTION OF AZIDES WITH SODIUM SULFIDE HYDRATE UNDER SOLVENT FREE CONDITIONS

Sodium sulfide hydrate has been employed for an efficient reduction of a variety of azides to the primary amines in good-to-excellent yields under solvent-free system and without perturbing many active functionalities such as ether, carbonyl, sulfonyl, and nitro.     

ORGANOPHOSPHORUS COMPOUNDS,XXVIII. THE REACTION OF TRIPHENYLPHOSPHINE SULFIDE WITH TETRACHLOROBENZOQUINONES

Abstract

The reaction of triphenylphosphine sulfide with tetrachloro-o-benzoquinone gives a complex of the corresponding hydroquinone and triphenylphosphine oxide. Elemental sulfur is the other product. The tetrachloro-p benzoquinone does not react to any noticeable extent under similar conditions. Several mechanisms are proposed to explain the results.     

D-葡萄糖D-果糖与硼的有机物形成配合物的稳定性研究

葡萄糖异构酶加速葡萄糖与果糖的平衡,平衡时果糖含量为42％左右,体系中加入一些硼酸盐,果糖的含量提高到80％左右,究其原因可能是由于葡萄糖和果糖与硼酸盐形成不同稳定性的配合物。虽然Roy,Conner,Daris,Belcher,Lorand等都已报导了这些配合物的稳定常数,概括结果分歧较大。Belcher曾首次报导了硼酸与D-果糖的配位数为     

手性亚砜类化合物的包结拆分

本文简要综述了手性亚砜类化合物的包结拆分研究,介绍了吡啶亚砜类化合物（包括苯并咪唑类抗胃溃疡药物）的包结拆分研究的最近进展。