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1.
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.  相似文献   

2.
以叔丁氧基钾为引发剂合成了由甲基丙烯酰基封端的聚氧化乙烯大单体,用VPO、GPC与UV进行了表征。其数均官能度接近0.90,分子量分布较窄(Mw/Mn<1.10)。将这类大单体与苯乙烯经自由基共聚,制备了接技共聚物。初步考察了这类接技共聚物对酚类化合物与环氧氯丙烷或β-溴乙苯反应时的相转移催化作用,发现产物收率随接技共聚物中氧化乙烯含量的增加而提高。  相似文献   

3.
Abstract

The mechanism of the reactions of diphenyl N-bromosulfilimine (I) with such nucleophiles as sulfides, phosphines and tertiary amines was investigated. In the presence of water, (I) reacts with sulfides or phosphines to afford the corresponding sulfoxides or the phosphine oxides in moderate yields; however, the reaction with tertiary amine gave only the N-t-aminosulfilimine derivative. The effect of ring size in the reaction with cyclic sulfides suggests that the reaction proceeds via initial bromine transfer from the nitrogen atom to the sulfur atom of the cyclic sulfides followed by SN2 type substitution of bromide on the sulfur atom of the cyclic sulfide with the sulfilimino group. The phosphine oxide obtained in the reaction of (I) with optically active methyl n-propyl phenyl phosphine was racemized but retained a small portion of the optical activity. In the case of tertiary amines, even 1,4-diazabicyclo-(2,2,2)-octane (DABCO), in which the back side of the nitrogen atom is blocked, reacted smoothly to afford the corresponding ammonium salts, suggesting the reaction to be of SN2 type on the nitrogen atom of the sulfilimine.  相似文献   

4.
5.
Abstract— Recent reports that have appeared in the literature concerning the reactions in aqueous media of hydroxyl radical with some transition-metal compounds containing bound organic molecules are discussed and experimental results on the reactions of hydroxyl radical with some platinum complex ions are presented. Emphasis is placed on the comparison of the behavior of the free ligand relative to that of the complexed and protonated forms. The occurrence of metal-ion complexation can modify to varying degrees the reactivity of organic entities towards hydroxyl radical and the subsequent behavior of the products. The influence of the metal center is considered to involve its Lewis acidity, π-bonding capabilities as well as features such as its formal oxidation state.  相似文献   

6.
Four series of new phosphorus compounds with general formulas Ⅰ, Ⅱ, Ⅲ and Ⅳ have been prepared by the reactions of phosphoro-(or phosphono-)bis-(isothiocyanatido)-thioates separately with amines. The structures of these compounds have been confirmed by IR and ~1HNMR. In addition, some of them have been further identified by MS and X-ray.  相似文献   

7.
Abstract

In contradiction to reports by others, it was shown that sulphinylamines do not give products of cycloaddition on reaction with aldehydes in aprotic solvents. However, in the presence of a protonogenic agent, crystalline products were precipitated for which an ammonium α-aminosulphonate salt structure was confirmed. These salts are formed as a result of consecutive hydrolysis of sulphinylamines, condensation of aldehydes with the resulting amines, and bisulphite anion addition to Schiff bases.  相似文献   

8.
新试剂APDNBT双波长法光度测定痕量银   总被引:3,自引:0,他引:3  
报道了以1-(4-安替比林基)-3-(2,4二硝基苯基)三氮烯(APDNBT)作显色剂,用双波长法光度测定痕量Ag(I)的显色条件.在Tween-80存在和pH为10.5~12.5范围,试剂与Ag(I)形成1:1的黄色配合物,其对试剂空白在478nm和548nm有最大和最负吸收峰,双波长法光度测定时,表观摩尔吸光系数为1.1×10~5.符合比耳定律的线性范围为0~12μg/25ml.方法用于合成试样及照相显影液中银含量的测定,回收率为97%~102%,相对标准偏差小于3.3%.  相似文献   

9.
Alkylene (dialkyl) dithiophosphate derivatives of thionyl chloride of the general formula (S)SS(O)Cl and (RO)2(S)SS(O)Cl where G = ─ CH2(CH3)2CCH2─, ─ CH2CH2CH(CH3)─, ─ C(CH3)2CH2CH(CH3)─ and R = i-C3H7, have been synthesized by reacting thionyl chloride with alkylene/dialkyl dithiophosphates in a 1:1 molar ratio in refluxing benzene. A similar reaction in a 1:2 molar ratio yields the corresponding products of the type (S2)2S═O and [(RO))2PS2]2S═O. It is interesting to note here that the sulfur atom of the thionyl chloride has been retained in the product, which is evidenced by sulfur analysis. The products thus obtained are light yellow colored semi solid (1:1 products) and orange colored liquids (1:2 products); and are soluble in common organic solvents. These new compounds have been characterized by elemental analysis, molecular weight measurements, and spectroscopic [IR and NMR (1H and 31P)] studies. These compounds are found to be biologically active against bacteria S.aureus and E.coli.  相似文献   

10.
Abstract

Thiourea and its derivatives easily form the complexes with compounds of CuII, FeIII, PtIV etc. By the formation of complexes as a rule redoxprocess proceeds to give an appropriate thiourea disulphide. It has been shown, that redoxprocess goes on prejudice on the derivatives of thiourea in that case when the thion-thiol tautomerism is possible.  相似文献   

11.
Abstract

The addition of the lithium carbanion of (R)-(+)-3,4-dimethoxybenzyl 2-methoxy-1-naphthyl sulfoxide 3 to cyclic nitrone 4, under kinetically controlled conditions gave isoquinoline sulfoxide derivatives 5 and 6 in high diastereoselectivities, Under equilibrium controlled conditions poor diastereoselectivity results. The chiral (R)-(+)-3,4-dimethoxybenzyl 2-methoxy-I -naphthyl sulfoxide 3 was easily prepared by the reaction of 3.4-dimethoxyben-zylmagnesium chloride 2 with (-)-(S)menthyl 2-methoxy-naphthalenesulfinate 1 in dry benzene. This methodology allows for the synthesis of the isoquinoline alkaloid (R)-(-)-norlaudanosine 8 in three efficient synthetic steps.  相似文献   

12.
13.
在浓硫酸和3-巯基丙酸催化下,3′-三氟甲基苯基-2,2,2-三氟苯乙酮(1)和甲苯于40~50℃下缩合反应8 h,制得中间体-1,1-二(4-甲基苯基)-1-(3′-三氟甲基苯基)-2,2,2-三氟甲基乙烷(2),继而在光照和N-溴代丁二酰亚胺促进下,将中间体氧化得到二羧酸-1,1-二(4-羧基苯基)-1-(3′-三氟甲基苯基)-2,2,2-三氟甲基乙烷(3),二步反应总收率为77.4%.采用Yamazaki体系,3和9,9-二[(4-氨基苯氧基)苯基]呫吨进行溶液亲核缩聚反应,制得了一种高分子量的(数均分子量为43000,分子量分布为1.8)新型含三氟甲基和呫吨结构的聚酰胺.该聚酰胺为非晶态结构并具有良好的透光率(λcutoff=330 nm),其玻璃化转变温度(Tg)为242℃,在氮气气氛中5%的热失重温度(Td5)为465℃,800℃时的残炭率为50%.聚合物易溶于N,N-二甲基乙酰胺(DMAc)、N-甲基吡咯烷酮(NMP)、间甲酚、吡啶(Py)和四氢呋喃(THF)等有机溶剂中,并可浇注得到韧性好和透明的薄膜,其拉伸强度为85 MPa,拉伸模量为2.0 GPa,断裂伸长率为10%.同时,该聚合物的体积电阻、表面电阻和介电常数分别为2.85×1015Ωcm,4.23×1014Ω和3.55(100 Hz),呈现了良好的电绝缘性能.  相似文献   

14.
Abstract

The structure and the coordination properties of sulfur compounds such as RS-(CH2)n-SR, (I), n=1-10 and RS-(CH2)nCOOR' (II), n=1,2 have been investigated by dipole moment, calorimetrie, IR-spectroscopy and cryoscopy methods.  相似文献   

15.
16.
Abstract

The reaction of triorganotin chlorides with sodium dialkyl thiophosphites proceeds to completion on refluxing the reactants in a 1:1 molar ratio for about ten hours. Similar reactions of triorganotin chloride with dialkyl thiophosphonate do not give comparable yields in the presence of triethylamine. The products formed are colorless volatile liquids having pungent odour, are miscible with common organic solvents and are found to be monomeric. Exposure of these compounds to atmospheric oxygen the thiophosphite [Sn-S-P] linkage was oxidized to a thiophosphate [Sn-O-P(S)] linkage. These complexes have been characterized by elemental analyses, molecular weight determination, IR, 1H NMR and 31P NMR spectral data.  相似文献   

17.
Abstract

The synthesis of some novel sulfur-containing spiroindole derivatives is reported, 2,3-Dihydrospiro [cycloalka[3,4][1,5] benzothiazepine-2,3′-[3H]indole]-2′-(1′H)-ones (V) were prepared by the reaction of 1,3-dihydro-3-(2-oxocycloalkylidene)indole-2(1H)-one (II) with 2-aminothiophenol in dry toluene. The compounds have been characterized on the basis of elemental and spectral studies.  相似文献   

18.
离子交换树脂法直接从卤水中制备溴化钠工艺研究   总被引:1,自引:0,他引:1  
本文在考查了Br2—Br-—Cl-—H2O体系中强碱性阴离子交换树脂对氯、溴的分离效果基础上,设计出二次树脂交换法直接从卤水中提取溴化钠的工艺路线,并对工艺中各操作条件进行了试验,依此工艺,溴化钠产品纯度达97%以上,溴的回收率为76%。  相似文献   

19.
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   

20.
一些芳族二元酸与二元醇的聚酯化反应过程包含非均相和均相两个反应阶段,针对这一反应特性,提出了二元酸在反应混合物中溶解度及反应清晰点的两个计算方程,并据此将Chen和Wu提出的自催化聚酯化反应的动力学模型修改为两个分别适用于非均相和均相反应阶段的速率方程.将这两个速率方程应用于双(对 羧苯基)苯基氧化膦与乙二醇的恒温自催化聚酯化反应,计算值与实验数据相一致,并计算得到了该反应的速率常数和活化能  相似文献   

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