烯丙基溴化钐与羰基化合物反应合成高烯丙基醇

高烯丙基醇是有机合成中的一类非常重要的中间体,以烯丙基金属试剂与羰基化合物加成反应为其主要合成方法,常用的金属烯丙基化合物有烯丙基锂(镁、锌、硼、铟、硅、锡、钛)等.由于烯丙基的Grignard试剂制备过程中常伴随着大量的烯丙基偶联反应,所以用烯丙基的Grignard试剂来合.     

脂肪酶催化作用下酰胺化反应的立体规则性研究

提出了在LipasefromCandidaAntrarctica(CAL)脂肪酶的催化作用下,含有手性中心C原子的胺类化合物酰胺化的异构选择性规则.与氨基相连的碳原子的立体结构对酰胺化反应有很大的影响.型胺类化合物呈R-型优先选择,型胺类化合物呈S-型优先选择.     

6-Halogenofulvenes and allylcyclopentadiene from nickelocene

In the presence of triphenylphosphine, nickelocene reacts with tetrachloromethane to give (trichloromethyl)cyclopentadiene, which can be dehydrohalogenated to 6,6-dichlorofulvene. It reacts analogously with tetrabromomethane and (trichloromethyl)benzene. 3-Bromopropene reacts with nickelocene to give allylcyclopentadiene.     

缩胺硫脲化合物的合成及其抗癌活性的研究

以肼基二硫代甲酸甲酯(Ⅱ)与相应的酮或醛反应,生成3-二取代甲撑基二硫代甲酸甲酯(Ⅲ).化合物与N-单取代哌嗪反应,制得不同取代基的标题化合物缩胺硫脲(Ⅰ),产率27～85.产物的结构用IR,NMR和元素分析证实,用磺酰罗丹明β蛋白染色法(SRB法)和四氮唑盐还原法(MTT法)检验了它们对鼠白血病(P-388)和人肺癌(A-549)细胞株的抑制活性.     

Electrophilic substitution of the acinitro group by an arylthio group in the dianion of 1,4-dinitrocyclooctatetraene

Conclusions The dianion of 1,4-dinitrocyclooctatetraene reacts with 2-nitrobenzenesulfenyl chloride by two parallel pathways: a) substitution of one of the acinitro groups by an arylthio group to form l-nitro-4-(2-nitrophenylthio)cyclooctatetraene and b) a two-electron oxidationreduction with the formation of 2,2'-dinitrodiphenyl disulfide. 4-Nitrobenzenesulfenyl chloride reacts with this dianion to give l-nitro-4-(4'-nitrophenylthio)cyclooctatetraene only upon activation with GaCl₃· 2,4-Dinitrobenzenesulfenyl chloride in the presence of GaCl3 reacts with this dianion only by the oxidation-reduction pathway.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 11, pp. 2590–2593, November, 1986.     

1—酰基—4—氯环己烷与取代芳烃的区域与立体选择性反应

从环己烯合成了１－酰基－４－氯环己烷，发现在其在ＡｌＣｌ３催化与苯，氯苯，溴苯等优先生成反式１－芳基－４－酰基环己烷，与联苯反应时选择性较差。     

On the Reaction of 3-Acetyl Coumarin with Alkyl Phosphites. Structural Confirmations Based on X-Ray Crystallography

3-Acetyl coumarin ( 1 ) reacts with dialkyl phosphites at 100°;C for 8 h to give the phosphonates 2 . Under the same experimental conditions, 1 reacts with trialkyl phosphites to form a mixture of the phosphonates 2 and 3 . The molecular structures of these products were elucidated by x-ray crystallography.     

Use of Alternating-Current Plasma Torch for Processing Potentially Hazardous Substances

The decomposition of tetrachloromethane and tetrafluoromethane by air plasma in the presence of methane has been studied using an ac plasma torch of up to 500 kW power with rail electrodes. Methane reacts with air in the partial oxidation mode to form hydrogen, which reacts with a halogen to produce the hydrogen halide.     

H_2O_2氧化N_2生成N_2O和H_2O机理的研究

采用量子化学计算方法研究了Ｈ２Ｏ２ 氧化Ｎ２ 生成Ｎ２Ｏ 和Ｈ２Ｏ 的机理．结果发现, Ｈ２Ｏ２ 氧化Ｎ２ 先通过１ 个四元环过渡态形成中间体Ｈ２Ｎ２Ｏ２ 分子,Ｈ２Ｎ２Ｏ２ 再通过一个五元环过渡态形成Ｎ２Ｏ和Ｈ２Ｏ．根据计算得到的每步反应的活化能,得知Ｈ２Ｏ２ 氧化Ｎ２ 生成中间体Ｈ２Ｎ２Ｏ２ 分子是整个反应的控制步骤．     

Direct kinetic studies of atom transfer and electron transfer reactions of hydroperoxo and high-valent oxo complexes of chromium

A macrocyclic hydroperoxo chromium complex reacts with triphenyl phosphine in an acid-catalyzed oxygen-atom transfer reaction, k = 850 M-2 s-1. In a competing process, the hydroperoxo complex is converted to a dioxo chromium(V) species, which reacts with PPh3 by electron transfer, k = 4.4 x 105 M-1 s-1.     

Pyridazine Derivatives and Related Compounds,Part 1. Some Reactions with 4-Cyano-5,6-Diphenyl-2,3-Dihydropyridazine-3-One

4-Cyano-5,6-diphenyl-2,3-dihydropyridazine-3-onc 1 reacts with phosphorous oxychloride to give 70% of the corresponding 3-chloro derivative 2. Treating 2 with anthranilic acid in butanol, 4-cyano-2,3-diphenyl-10H-pyridazino[6,1-b]quinoxaline-10-one, 3 was obtained. Compound 1 reacts with phosphorous pentasulphide to give 3-mercapto derivative 4, which was converted by acrylonitrile to S-(2-cyanoethyl)pyridazine derivative 5. Compound 4 reacts with ethyl bromoacetate and with phenacyl bromide gave the corresponding thieno[2,3-c] pyridazine derivatives 8, 9, Alkylation of 1 with ethyl chloroacetate afforded 3-0-carbethoxymethyl derivative 10. Compound 10 reacts with amines (aniline, hydrazine) to give the corresponding amide and acid hydrazide 13, 12 respectively. Hydrolysis of 10 with sodium hydroxide gave the corresponding acid derivative 11. Treating 1 with methyl iodide, 3-0-methyl derivative 14 was obtained, which was converted by ammonium acetate/acetic acid to 3-amino-4-cyano-5,6-diphenyl pyridazine 15. Compound 1 reacts with methyl magnesium iodide gave 4-acetyl derivative 16, which was reacted with hydrazine, phenyl hydrazine and with hydroxylamine to give the substituted I H pyrazolo [3,4-c] pyridazine 17 a,b and isoxazolo [5,4-c] pyridazine 18 derivatives respectively.     

A FACILE APPROACH FOR THE SYNTHESIS OF α -HALOGENATED ALKYLIDENEDIPHOSPHONATES BY REACTION OF ALKYLLITHIUM WITH CHLOROPHOSPHATE AND HALOGEN REAGENT

Alkyllithium reacts with chlorophosphate to generate the α -lithio- alkylidenediphosphonate, which further reacts with halogen reagents to afford corresponding α -halogenated alkylidenediphosphonates.     

β—环糊精衍生物的金属配合物催化RNA的水解

用 β-环糊精 (β- CD)与马来酸酐合成了双 (6 -氧 -丁烯二酸单脂 ) - β- CD(简称 E1 ) ,用 KI对 E1 进行取代 ,生成了双 (6 -碘 ) - β- CD,其与组氨酸在 Na OH溶液中反应 ,生成双 (6 -氮 -组胺酸 ) - β- CD(简称 E2 ) ,E2 分别与 Mg( )、Zn( )、Fe( )和 Fe( )形成配合物 .研究了这 4种金属配合物对 RNA的水解 ,并与 Na OH水解 RNA进行了比较 ,发现 E2 · Fe( )对 RNA的水解能力可达到 Na OH水解 RNA能力的 96 .9% .     

Reaction of gem-nitronitroso-compounds with triethyl phosphite

2-Nitro-2-nitrosopropane reacts with triethyl phosphite by deoxygenation of the nitroso- group to give 2-nitriminopropane; 1-nitro-1-nitrosocyclohexane reacts similarly. The reaction proceedsvia an intermediate detectable byNMR; possible structures for this intermediate and for the course of the reaction are discussed. Some reactions of nitrimines are also reported.     

The reaction of allyl iodide with ketones in the presence of cerium amalgam. An efficient method for the preparation of homoallylic alcohols

Allyl iodide reacts in situ with cerium amalgam to generate allyl cerium iodide, which in turn reacts with ketones to yield homoallylic alcohols in good yields.     

Formation and characterization of mononuclear and dinuclear manganese oxide-dioxygen complexes in solid argon

A manganese atom reacts with dioxygen to form the previously characterized MnO 2 molecule in solid argon under UV-visible light irradiation. Subsequent sample annealing allows the dioxygen molecules to diffuse and to react with MnO 2 to give the (eta (2)-O 2)MnO 2 complex, which is characterized to be a side-on bonded peroxo manganese dioxide complex. The manganese tetraoxide MnO 4, which was predicted to be less stable than the (eta (2)-O 2)MnO 2 isomer, was not observed. However, the (eta (2)-O 2)MnO 2 complex reacts with another weakly coordinated dioxygen to give the (eta (2)-O 2)MnO 4 complex via visible light irradiation, in which the manganese tetraoxide is coordinated and stabilized by a side-on bonded O 2 molecule. Manganese dimer reacts with dioxygen to form the cyclic Mn(mu-O) 2Mn cluster spontaneously upon annealing, which further reacts with dioxygen to give the (eta (2)-O 2) 2Mn(mu-O) 2Mn cluster, a side-on bonded disuperoxide complex with a planar D 2 h structure.     

Synthesis and Mechanistic Study of Triheterocyclic 4H‐Pyrimido[2,1‐b]benzothiazole derivatives,One‐Pot Three‐component Reaction under Solvent‐Free Conditions

An efficient method has been developed for the preparation of 4H‐pyrimido[2,1‐b]benzothiazole derivatives by the condensation of aldehydes, β‐ketoester, and 2‐amino benzothiazole under solvent and solvent‐free conditions using various catalysts. The reaction uses benzothiazole as a new component, and good yield is obtained at 60–65°C under solvent‐free conditions. Atom economies, good yield, environmentally benign, and easy to work‐up are some of the important features of this protocol. The present study suggests that acetic acid and metal catalysts follow different mechanism. In acetic acid, 2‐amino benzothiazole reacts with benzaldehyde, and resultant intermediate reacts with ethyl acetoacetate to give final product, whereas in the presence of metal catalysts, 2‐amino benzothiazole first reacts with ethyl acetoacetate, and resultant intermediate reacts with benzaldehyde to give pyrimido[2,1‐b]benzothiazole.     

Determination of benzoyl bisulphide by desulphurisation and solvolysis

Benzoyl disulphide is rapidly and quantitatively desulphurised to the monosulphide by reaction with triphenylphosphine in aqueous methanol at 25 degrees . The monosulphide reacts with methanol to form thiobenzoic acid and methyl benzoate. Benzoyl disulphide also reacts with methanol in solutions containing ammonium acetate or sodium acetate yielding thiobenzoic acid, methyl benzoate and elemental sulphur. Benzoyl disulphide and sulphur were detected by their polarographic reduction waves. Thiobenzoic acid was detected by its polarographic oxidation wave and yields were determined by amperometric silver nitrate titrations.     

Lewis acid mediated allylation of 2-alkanoyl-1,4-quinones with allylsilane and allylstannane

Allyltrimethylstannane reacts uith 2-alkanoyl-1,4-quinones regioselectively to afford conjugate addition products which can be derived to 2-alkanoyl- 3-allylhydroquinone diacetate, while allyltriphenylsilane reacts with the quinone to give naphthofuran.     

On the possibility of LiH formation on Li surfaces in wet electrolyte solutions

Fresh lithium reacts with gaseous hydrogen to form surface species which are probably LiH. Li may also react with the H₂ that is formed by its reaction with H₂O contamination in 1–3 dioxolane solutions. The LiH, when formed, is metastable because it reacts with trace water and the solvent.