REACTIONS OF TETRAPHOSPHORUS DECASULFIDE AND LAWESSON'S REAGENT WITH SILANES CONTAINING A FEW Si-O BONDS

Abstract

The reactions of tetraphosphorus decasulfide and Lawesson's reagent with tetra-, tri- and dialkoxysilanes were studied. On the basis of these reactions, new S-silyl esters of phosphorus(V) thioacids have been prepared. The prepared compounds were identified by IR, ¹H, and ³¹P NMR and mass spectra as well as elemental analyses.     

SYNTHESIS AND CHARACTERIZATION OF THE FIRST BORANE ADDUCTS AND BORON CATIONS OF SOME N-ALKYL AND N-AMINOTRIPHENYLPHOSPHORANIMINES

Abstract

The first borane adducts of N-alkyl and N-aminotriphenylphosphoranimines, Ph₃P[dbnd]N—R, were prepared by two different general synthetic methods. The first method involved displacement of THF (tetrahydofuran) from THF-borane by the free imines, and the second employed the reaction of LiBH₄ with iminium bromides, Ph₃P[dbnd]N(R)HBr, in diethyl ether. Imine boranes, Ph₃P[dbnd]N(R)BH₃, were synthesized where R [dbnd] methyl, ethyl, n-propyl, isopropyl, isobutyl, t-butyl. dimethylamino, phenylamino, and methyl, phenylamino as the nitrogen attached groups. Symmetrical boron cations, (Ph₃P[dbnd]NR)₂, BH₂ ⁺, where R = methyl, ethyl, and n-propyl, were synthesized by displacement of iodide from in-situ generated iodoborane adducts, Ph₃P[dbnd]N(R)BH₂I, by the free imines. An attempt to form an unsymmetrical boron cation from (CH₃)₃ NBH₂I and Ph, P[dbnd]N(n-C₃H₇) resulted only in a mixture of the corresponding symmetrical boron cations. Physical, chemical and spectral properties of the borane adducts and boron cations, namely thermal and hydrolytic stabilities, infrared and NMR data are presented. Oxidative and reductive stabilities of the boron cations were studied. The borane adducts can be chlorinated with either HCI or Ph₃CCI. Relative base strengths of some imines were determined by following the exchange of BH₃ between borane adducts of (CH₃)₃ N or 4- (CH₃)C₅H₄ N and the imines via NMR.     

SYNTHESIS OF THE NOVEL CHIRAL POLYMERS WITH MULTIDENTATE LIGAND AND RESOLUTION OF DL-AMINO ACIDS

A new way for synthesizing styrenic type of chiral resins grafting to multidentate ligand has been found. The synthetic scheme is proved to be practical by means of elemental anaysis, IR spectra and metal adsorbility. The resolving power of the new chiral ligand resins coordinated with copper (Ⅱ) as stationary phases has been discussed based on HPLC, and some points of view about the compositions of mobil phase and mechanism of resolution are presented.     

NEW RADIOHALOGENATED ALKENYL TELLURIUM FATTY ACIDS

Abstract

Radiolabeled long-chain fatty acids have diagnostic value as radiopharmaceutical tools in myocardial imaging. Some applications of these fatty acids are limited due to their natural metabolic degradation in vivo with subsequent washout of the radioactivity from the myocardium. The identification of structural features which will increase the myocardial residence time without decreasing the heart uptake of long-chain fatty acids is of interest. Fatty acids containing the tellurium heteroatom were the first modified fatty acids developed and show unique prolonged myocardial retention and low blood levels. Our detailed studies with radioiodinated vinyliodide substituted tellurium fatty acids demonstrate that heart uptake is a function of the tellurium position. New techniques of tellurium and organoborane chemistry have been developed for the synthesis of a variety of radioiodinated iodoalkenyl tellurium fatty acids.     

提硼离子交换树脂研究进展

简单介绍了离子交换树脂法提取硼的原理,从葡甲胺、多元醇、糖类、邻-二元酚类不同功能基以及聚苯乙烯、聚丙烯酸酯、无机-有机复合型树脂及天然高分子等不同基质材料的角度综述了提硼离子交换树脂的研究现状,认为葡甲胺是目前使用效果最好的功能基化试剂,而基质材料则各有优缺点.同时对硼离子交换树脂在水处理、环境保护、提取分离等领域的应用进行了概括,并对新型提硼树脂的研究进行了展望.     

N-酰基氨基酸系列表面活性剂的合成和应用

本文综合评述和介绍了N－酰基氨基酸系列表面活性剂的合成及应用（特别在农业、生物化学和药物制造领域的应用）的一些近年来的研究,进展指出了进一步的研究方向,并报道了我公司开发此类产品的情况。     

电感耦合等离子体质谱法测定香精香料中的硼元素

采用微波消解-电感耦合等离子体质谱法(ICP-MS)测定香精香料中硼元素的含量。对微波消解样品前处理条件和仪器参数进行了优化,该方法硼元素检出限为1.005 ng/mL、平均回收率为106.1%、精密度为6.15%(n=5),并用茶叶国家标准物质(GBW10016)对分析方法进行了校准。该方法适合于香精香料中硼元素的测定。     

微波消解-ICP—AES法测定钴基合金中的硼

采用微波消解-ICP-AES法测定钴基合金中硼元素。通过试验探讨了钴基高温合金中基体元素,主量元素如铬、钨、钼等对硼元素分析谱线的光谱干扰情况,采用基体匹配法对基体干扰进行校正,确定了合适的分析谱线。方法的线性范围为0～8 mg/L,检出限为0.0003%。测定结果的相对标准偏差为1.88%～6.04%(n=6),回收率为92.0%～104.2%。     

SUBSTITUENT DIRECTIVE EFFECTS IN THE FRIEDEL-CRAFTS SYNTHESIS OF SUBSTITUTED PHENOXAPHOSPHINIC ACIDS

Abstract

Although meta-substituents on diphenyl ethers block attack at the para-position in the reaction with phosphorus trichloride and aluminium chloride, in some cases phosphorylation occurs in the even sterically more shielded ortho-position, leading to mixtures of isomeric phenoxaphosphinic acids. This effect and the obtained ratios of isomers can be explained by different substituent directive effects in a two step reaction mechanism.     

SYNTHESIS AND STRUCTURE OF 1,2-BIS(DIPHENYLPHOSPHINO)ETHANE COMPLEXES OF COPPER(I) ACETATE. CATALYSTS FOR THE DECARBOXYLATION OF CARBOXYLIC ACIDS

Abstract

Several dimeric complexes of copper(I) acetate with bidentate phosphine ligands have been synthesized. The solid-state structure of one of these derivatives, dppe(CuO₂CCH₃)₂, where dppe = 1,2-bis(diphenylphosphino)ethane, has been determined. The complex is shown to exist in the solid-state as a polymeric chain of dimeric copper(I) units containing a dppe and two acetate ligands, with the dimers being linked together via weaker Cu-O interactions. The Cu-Cu bond length in the dimeric units is considerably longer, at 2.712(2) Å, than that observed in copper(I) acetate of 2.556(2) Å. The use of these derivatives as catalyst precursors for the catalytic decarboxylation of cyanoacetic acid to acetonitrile and carbon dioxide is discussed. Crystal data for dppe(CuO₂CCH₃)₂: space group P2_i/n,a = 14.976(6) Å, b = 11.676(3) Å, c = 16.999(6) Å, β = 107.59(3)°, Z = 4, R = 7.33%     

聚乙二醇相转移催化羧酸酯的合成

聚乙二醇相转移催化羧酸酯的合成谢筱娟，杨高升，杨富国，宋雪清（安徽师范大学化学系芜湖２４１０００）关键词聚乙二醇，相转移催化，酰化反应，羧酸酯通常羧酸酯的制备是利用醇与羧酸、酰氯或酸酐反应，但这个方法对有立体位阻的醇不太适宜［１］，为此，为寻找好的方...     

反式氢化茚酮的合成在全合成甾体上的应用

反式氢化茚酮是全合成甾体的合成子。本文综述了五种合成方法:即分子内 Diels-Alder 反应,分子内 Michael 反应;联合 Cope-Claisen 重排;Lewis 酸催化环合γ,δ-不饱和羰基化合物以及二环庚烷的裂解。     

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     

SYNTHESIS OF NEW ESTRONE DERIVATIVES OF AMINO ACIDS AND PEPTIDES

A series of estrone derivatives of amino acids and peptides haze beensynthesized by different coupling reagents and the binding affinity of deblocked derivativesto the estrogen receptor of rats uteri have been measured by a comptetive radiometric bind-ing assay.     

脂肪酸离子排斥分配色谱分离中的吸附作用

酸在氢型阳离子交换树脂柱上的分离机理已有研究,Glod等根据离子排斥色谱中的Donnan膜平衡,推导出分配系数K_d与酸离解常数K_a的关系,能大致预测酸的流出顺序,但不能说明为什么pK_a极为相近的有机酸却有较大的保留时间差别.Bafna等从分子吸附的角度考察了某些有机酸在阳离子交换树脂上的吸附平衡和洗脱行为.本文从有机酸离子排     

pH和盐对树脂吸附芳香酸的影响研究

通过三甲胺修饰超高交联聚苯乙烯树脂NJ-00制备了一种新型树脂(NJ-03),树脂性质表征说明,通过改性季胺基被成功引入,树脂骨架上增加了一定数量的碱性基团。研究了pH、盐浓度对芳香酸类化合物在NJ-03树脂上吸附的影响,并与商品大孔强碱阴离子交换树脂D-201以及大孔弱碱阴离子交换树脂D-301进行对比,探讨了pH和盐浓度影响吸附的机理。     

THE ASYMMETRIC SYNTHESIS OF AMINO ACIDS UNDER POLYMER-SUPPORTED PHASE TRANSFER CATALYTIC CONDITION

The optical α-amino acids were synthesized under room temperature byalkylation of N-(diphenyl methylene) glycine t-butyl ester under polymer-supported phasetransfer conditions using polymer-supported cinchonine (or quinine) alkaloids as chiralphase transfer catalysts and dichloromethane as solvent, followed by hydrolysis of theabove intermediates introduced to the final products-optical α-amino acids. This is anew method for the asymmetric synthesis of α-amino acids. The influences of catalyst,temperature, substrates, and organic solvents on the chemical yield and optical purities ofproducts were studied.     

PHOSPHORUS-CONTAINING AMINOCARBOXYLIC ACIDS. COMMUNICATION IV.1 A CONVENIENT METHOD OF PHOSPHONIC ACIDS SYNTHESIS

Abstract

The communication is concerned with the synthesis of phosphonic aminocarboxylic acids by phosphorylation of diethyl ω-halogen alkyl acetamidomalonates with tris(trimethylsilyl) phosphite, followed by alcoholysis and acid hydrolysis of the resulting intermediate esters.     

腐植酸接枝共聚物对赤红壤K~+吸附与解吸的影响

本文研究了经施用硝基腐植酸与丙烯酸、丙烯酰胺三元接枝共聚物的赤红壤中钾离子的吸附和解吸的影响。实验结果表明,施用共聚物的土壤可减少土壤对中钾离子的吸附,增加土壤对钾离子的解吸,提高钾离子的抗淋溶。改良后的土壤可减少土壤钾的损失,提高钾肥的利用率。     

薄壳型手性配体交换HPLC填料的合成及用于DL-氨基酸拆分

将含有少量二乙烯苯的丙烯酸甲酯涂敷于聚二乙烯苯珠体表面上进行聚合，得到了表面涂层树脂，通过红外光谱估算出涂层厚度为~2μm。涂层树脂依次与乙醇胺、环氧氯丙烷和L-脯氨酸反应，得到薄壳型手性配体交换树脂，此树脂的Cu（Ⅱ）络合物作为高效液相色谱的填料对DL-氨基酸进行了拆分。