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1.
Abstract

A study of the synthesis of phosphoramidates from phosphites and benzothiazol-2-yl-sulphenamides, indicates that a quinquecovalent phosphorane is an intermediate. Since the initial step in this reaction does not involve attack of phosphorus on nitrogen, it is unlikely that these sulphenamides will act as electrophilic aminating agents towards non-phosphorus nucleophiles. An efficient new method for preparing benzothiazol-2-yl-sulphenamides is reported.  相似文献   

2.
(Organylthio)chloroacetylenes react with aliphatic 1,2-dithiols in dimethyl sulfoxide at 20–25°C in the presence of a two-fold molar excess of alkali to form 2-[(alkylthio)methyliden]-1,3-dithiolanes in up to 66% yield.  相似文献   

3.
Abstract

Dialkylsulfoxylates undergo reactions with alkylhalides and other alkylating agents to give sulfinic acid esters, which were characterized by IR-, 1H-NMR- and mass-spectra.  相似文献   

4.
Abstract

The dialkylphosphinic acids, 5a-5e, can be obtained by reacting bis(trimethylsiloxy)phosphine with the highly reactive alkyl halides, 2a-2e, in the presence of chlorotrimethylsilane and triethylamine, followed by ethanolysis of the resulting trimethylsilyl dialkylphosphinates, 4a-4e.  相似文献   

5.
Abstract

Photochemical reactions of elemental sulfur with several olefins were studied. Irradiation of a mixture of elemental sulfur and norbornylene with 3500 Å light afforded 3,4,5-trithiatricyclo[5.2.1.0]decane (1) and 2,3-epithionorbornane (2). Similarly, several thiane derivatives (4–6) were found to be formed by the photolysis of a mixture of cyclohexene and sulfur.  相似文献   

6.
Reaction of the Lawesson's reagent (LR) with aliphatic 1,2- and 1,3-diols as well as with aromatic 2,2′-dihydroxybiphenyl led to new products. Stable di-tert-butylammonium salts of bis-anisyldithiophosphonic acids 6 were isolated and were then converted into unique 9-, 9-, and 10-membered cyclic disulfides 7 and into S,S-dimethyl esters 8. The salts of bis-anisyldithiophosphonic acids 6 were shown to be capable of splitting the disulfide bond of Ellman's reagent.  相似文献   

7.
环戊烷选择性氧化用VPO催化剂的合成新方法   总被引:4,自引:1,他引:4  
陈胜利  邵汉成 《催化学报》1999,20(5):553-556
研究了VPO催化剂时还原溶剂对VPO的结构及催化性能的影响,VPO的合成方法如下:(1)V2O5与H3PO4反应生成磷酸钒;(2)用不同的还原溶剂还原磷酸钒得到VPO催化剂前身;(3)活化VPO催化剂前身,研究的还原溶剂有;异丁醇,异丁醇-苯甲醇,异丁醇-石油醚和正己醇。结果表明,使用异丁醇-石油醚作还原溶剂,只能生成VOHPO4.0.5H2O晶体;使用其它溶剂则会生成VO(H2PO4)2和VOH  相似文献   

8.
Abstract

The reaction of electron-rich alkynes such as ethoxyacetylene or propynyldiethylamine with a transient terminal phosphinidene complex such as [PhP?W(CO)5] directly yields the corresponding phosphole complexes via a formal [2 + 2 + I] cycloaddition involving two molecules of alkyne and one phosphorus center.  相似文献   

9.
Abstract

2-Amino-1.1.3-tricyanoprop-l-ene (1) reacted with thioglycollic acid to afford the key compound for this study namely: 2-amino-I,I-dicyano-3(2-thiazolin-4-on-2-yl)prop-1-ene 2. 2 reacted with hydrazines to afford the thiazolylmethylaminopyrazole derivatives 3 and 4. The reaction of 2 with diazotised primary aromatic amines afforded coupling products which were cyclised to the hydrazothiazolonylpyridazine derivatives 7. The reaction with aromatic aldehydes gave the his-ylidene derivatives 8. Structures are assigned based on elemental and spectroscopic analysis.  相似文献   

10.
在略高溫度下,通过氯化锂和金属钠在氫气氛中的反应,得到了氢化锂和氯化钠的混合物。用通常的Schlesinger法将得到的混合物用于合成氢化铝锂。反应的副产物是氯化锂和氯化钠的混合物,可用不同方法将其分离,所得氯化锂用于再循环。  相似文献   

11.
12.
4,4′—二硝基重氮氨基本(DNAAB)是一种测定镉、汞等金属离子的优良的三氮烯试剂[1],其合成一般是用H2SO4—NaNO2作重氮化试剂,分重氮化和偶联两步加入反应物合成[2]。但在H2SO4作用下,NaNO2易放出NO2有毒气体。我们摸索出以亚硝酸正丁酯为重氮化试剂,以本方法合成,克服了上面缺点,并且产品纯度高,收率也较文献方法好[3]。研究了其与Cd2 的显色反应,以双峰双波长法测定,摩尔吸光系数达2.52×105L·mol-1·cm-1,用拟定方法测定了人发中镉含量,结果令人满意。1 实验部分1.1 仪器与试剂仪器:752型紫外光栅分光光度计(上海申化仪表自…  相似文献   

13.
报道了新试剂7-(苯并噻唑-2-偶氮)-8-羟基喹啉-5-磺酸(BTHQSA)的合成方法,研究了该试剂与钴显色反应情况.结果表明,在pH3.94乙酸-乙酸钠、乳化剂OP存在下,Co-BTHQSA-OP配合物最大吸收波长为582nm,表观摩尔吸光系数ε_(582)=-5.7×10~4,钴的含量在0~12μg/25ml内,服从比耳定律.  相似文献   

14.
Photosensitized oxidation of the eye lens proteins, the crystallins, is thought to lead to protein crosslinks and high molecular weight aggregates. Such protein modifications may be important factors in the formation of lens opacities or cataracts. We focus attention here on type 2 photo-oxidation involving the reaction of singlet oxygen (1O2) with crystallins and some "control" proteins. We find that: (1) trp residues are oxidized to N-formyl kynurenine and related products, but this in itself does not lead to the production of high molecular weight protein aggregates of the protein; (2) tyr residues react with 1O2 but we do not detect dihydroxyphenylalanine or bityrosine nor are protein crosslinks formed as a result; (3) oxidation of his residues appears necessary for high molecular weight protein covalent aggregates to form. Proteins devoid of his, e.g. melittin or bovine pancreatic trypsin inhibitor, do not form high molecular weight products upon reaction with 1O2. Prior reaction and blocking of his inhibits the crosslinking reactions. (4) The oxidized protein is seen to be more acidic than the parent and has an altered tertiary structure. (5) Among the crystallins, reactivity towards 1O2 varies in the order gamma greater than beta greater than alpha and also gamma A/E greater than gamma D greater than gamma B crystallin.  相似文献   

15.
研究了新配体TTBA与二阶铜离子生成配合物的光度特征和电化学 特征。在较宽的PH范围内,新试剂和铜离子形成1:2的棕黄色配合物,并且在一定范围内具有良好的线性关系。通过电化学方法和光度法都可以证明,文中合成的新试剂氮三没食子酸三乙胺测定Cu^2 具有很高的灵敏度和选择性,在实际生产中具有一定的应用价值。  相似文献   

16.
17.
Abstract

The reaction of organophosphorus disulfides with trialkylsilylcyanide has been investigated. It provided direct evidence for the intermediacy of thiocyanidate >P(X)SCN, X=O, S in this type of reaction. The disulfides studied involved phosphoryl, phosphonyl and/or phosphinyl disulfides. They have been shown to follow the common mechanism. The studied reaction of thiophosphoryl disulfides with trimethylsilylcyanide represents a new and highly efficient route to tetraalkylpyrophosphoro-trithioates.  相似文献   

18.
研究了对羧基苯基荧光酮与铀(Ⅵ)的显色反应。在pH6.5氨水-乙酸缓冲溶液和阳离子表面活性剂溴化十六烷基三甲铵存在下,铀(Ⅵ)与对羧基苯基荧光酮发生灵敏的显色反应,其配合物最大吸收峰位于570nm,表观摩尔吸光系数为7.52×104L.mol-1.cm-1。铀(Ⅵ)浓度在0~100μg/25mL符合比耳定律。在室温下,试剂与铀(Ⅵ)的显色反应立即完成,配合物吸光度至少可以稳定12h。体系具有较好的选择性,绝大多数金属离子有较高的允许量,铀(Ⅵ)的伴生元素钍和稀土允许量达10mg,方法已应用于水样中痕量铀的测定,结果满意。  相似文献   

19.
<正> 近年来,有机化学家应用不溶性聚合物试剂α-二醇、β-二醇树脂对二元醛酮单功能化反应做了大量的工作。笔者在相转移催化下,用交联的氯甲基化聚苯乙烯与2,3-二巯基丙醇(BAL)进行Williamson反应,合成了一个新的不溶性聚合物醛酮保护试剂——BAL-树酯Ⅲ(巯基容量=2.5m mol/g)。并利用鱼钓原理以Ⅲ与对称二醛(对苯二甲  相似文献   

20.
陈祖兴 《应用化学》1993,10(4):92-94
茉莉酮和二氢茉莉酮是一类名贵的香料,此类化合物的合成一直是人们所关注的问题。已有许多报道,其中包括庚醛、1-硝基庚烷与甲基乙烯基酮进行Michael加成和以硝代甘缩酮与庚醛进行硝-醛缩合制得1,4-二酮,再进行分子内缩合为二氢茉莉酮。这些合成方法,有的对反应条件要求较苛刻,不易操作,有的则反应步骤较多,收率低。最近,白俊才等以甲基乙烯基酮和1-己烯为原料,合成了二氢茉莉酮,此法虽然新颖,但氧硼杂环己烷中间体  相似文献   

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