- Self-Healing Molecular Crystals
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One of the most inevitable limitations of any material that is exposed to mechanical impact is that they are inexorably prone to mechanical damage, such as cracking, denting, gouging, or wearing. To confront this challenge, the field of polymers has developed materials that are capable of autonomous self-healing and recover their macroscopic integrity similar to biological organisms. However, the study of this phenomenon has mostly remained within the soft materials community and has not been explored by solid-state organic chemists. The first evidence of self-healing in a molecular crystal is now presented using crystals of dipyrazolethiuram disulfide. The crystals were mildly compressed and the degree of healing was found to be 6.7 %. These findings show that the self-healing properties can be extended beyond mesophasic materials and applied towards the realm of ordered solid-state compounds.
- Commins, Patrick,Hara, Hideyuki,Naumov, Pan?e
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- Synthesis and Properties of Tetra-4-{[(1,1'-biphenyl)-4-yl]oxy}phthalocyanines and Their Sulfonic Acid Derivatives
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The template condensation of 4-{[(1,1'-biphenyl)-4-yl]oxy}phthalonitrile with cobalt, copper, and magnesium acetate resulted in the synthesis of metal phthalocyanines. Sulfochlorination of the latter followed by hydrolysis gave the corresponding sulfonic acid derivatives. The spectral characteristics and chemical properties of the synthesized compounds were studied.
- Tikhomirova,Peledina,Maizlish,Vashurin,Shaposhnikov
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- A new water-soluble sulfonated cobalt(II) phthalocyanines: Synthesis, spectral, coordination and catalytic properties
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Novel complexes of cobalt(II) with sulfonated derivatives of phthalocyanines are synthesized. The influence of the sulfonated group's number in peripheral substituent on solubility of macrocycle and ability to form ordered structures in solution is showed. Transition from H-aggregates to monomeric phthalocyanine structures and sandwich-type dimers was found during formation of metallophthalocyanine complexes with 1,4-diazabicyclo[2.2.2]octane. The catalytic activity of metallophthalocyanines was studied on the model of Merox process
- Vashurin, Artur,Filippova, Anna,Znoyko, Serafima,Voronina, Alena,Lefedova, Olga,Kuzmin, Ilya,Maizlish, Vladimir,Koifman, Oscar
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- Catalytic properties of cobalt complexes with tetrapyrazino porphyrazine and phthalocyanine derivatives
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The catalytic activity of cobalt complexes with octaphenyltetrapyrazinoporphyrazine and phthalocyanine derivatives containing branched peripheral substituents is studied in heterogeneous catalysis of the oxidation of sodium diethyldithiocarbamate (SDC) with atmospheric oxygen. Cobalt phthalocyanines are shown to display higher catalytic activity than cobalt complexes with octaphenyltetrapyrazinoporphyrazine. The highest efficiency of heterogeneous catalysts is attained at temperatures of 298-303 K.
- Vashurin,Kuzmin,Litova,Petrov,Pukhovskaya,Golubchikov
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- ESR spectra and electronic structure of the MoO3+ complex with the dithiocarbamate ligand
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ESR spectra of liquid and frozen benzene solutions of isotope-enriched 95,97,98MoVO(dtc)3 complexes ([xMo] > 95%, dtc is the N,N-diethyl dithiocarbamate ligand) and their solid solutions in a matrix of tetraethylthiuram disulfide were studied in the X-range. Comparison of the experimental and calculated parameters of the ESR spectra shows that the axial symmetry of the magnetic tensors does not contradict the low symmetry of the complex, in which the "ylic" oxygen and five of six S atoms in three dithiocarbamate ligands form the coordination sphere of the metal.
- Rakitin,Ivanov
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- Non-covalent associates of metal phthalocyanines: the role of axial ligand and catalytic activity
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The problem about the role of the coordinated exobidentate ligand in the formation of dimeric structures of sulfonated cobalt phthalocyanine derivatives is considered. The size of the peripheral substituent of the macrocycle and remoteness of the ionogenic group from the macrocycle play the key role in the formation of dimers of a specified type. As the extension of the peripheral substituent of the macrocycle increases, the stability of dimeric associates of the Н-type decreases and that of the associates formed due to the donor—acceptor interaction (J- and Т-aggregates) increases. The latter can be stabilized by hydrogen bonds at the periphery of the macromolecule. A series of catalytic activity of the macrocycles under study is inverted compared to the series of stability of the H-dimers.
- Vashurin
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- Electrochemically Controlled Cationic Polymerization of Vinyl Ethers
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Control of polymer initiation, propagation and termination is important in the development of complex polymer structures and advanced materials. Typically, this has been achieved chemically, electrochemically, photochemically or mechanochemically. Electrochemical control has been demonstrated in radical polymerizations; however, regulation of a cationic polymerization has yet to be achieved. Through the reversible oxidation of a polymer chain end with an electrochemical mediator, temporal control over polymer chain growth in cationic polymerizations was realized. By subjecting a stable organic nitroxyl radical mediator and chain transfer agent to an oxidizing current, control over polymer molecular weight and dispersity is demonstrated and excellent chain end fidelity allows for the synthesis of block copolymers.
- Peterson, Brian M.,Lin, Song,Fors, Brett P.
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- Catalytic properties of polymer matrix-immobilized cobalt complexes with sulfonated phthalocyanines
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Enhancement of the catalytic activity of phthalocyanine catalysts by their immobilizing on polymer matrices has been studied. It has been found that the immobilization of sulfonated cobalt phthalocyanines on polymers enhances their catalytic activity in the oxidation of sodium diethyldithiocarbamate with air oxygen under mild conditions.
- Vashurin,Badaukaite,Futerman,Pukhovskaya,Shaposhnikov,Golubchikov
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- Interaction of Diethyldithiocarbamate with n-Type Cadmium Sulfide and Cadmium Selenide: Efficient Photoelectrochemical Oxidation to the Disulfide and Flat-Band Potential of the Semiconductor as a Function of Adsorbate Concentration
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The behavior of sodium diethyldithiocarbamate, Na, at n-type semiconducting CdX (X = S, Se) in CH3CN/0.2 M NaClO4 has been studied.The Et2NCS2- interacts strongly with the CdX surface and shifts the flat-band potential, EFB, up to 1.0 V more negative with increasing Et2NCS2- concentration.The concentration dependence of the shift in EFB has been studied in the range 0-0.2 M, with 0.01 M Et2NCS2- being sufficient to shift EFB the maximum amount.The shift in EFB is due to excess negative charge on the CdX surface due to the presence of adsorbed dithio carbamate.The shift in EFB is assumed to be proportional to Et2NCS2- coverage.A plot of EFB with change in bulk concentration of Et2NCS2- can be modeled by using Langmuir adsorption isotherms.Adsorption data for two bis(dithiocarbamates), Na+2->2 and Na+2->2, show that maximum shifts of EFB are obtained at lower solution concentrations than for Et2NCS2-.The data show that the equilibrium constant for dithiocarbamate binding is somewhat greater (by a factor of 2) for CdS than CdSe.The value of EFB in the presence of 0.2 M Et2NCS2- measured by interfacial capacitance accords well with the electrode potential corresponding to onset of photoelectrochemical oxidation upon illumination with light of energy greater than the band gap, Eg, of the semiconductor.High current efficiency (at least 98percent) can be maintained to large extent conversion (70percent) in the photoelectrochemical oxidation of Et2NCS2- to 2 at either illuminated CdS or CdSe.Oxidation of Et2NCS2- can be effected at an electrode potential significantly more negative than of Et2NCS2-/2, showing that visible light can be used to drive the oxidation in an uphill sence.Compared to a Pt anode, the CdX (X = S, Se) photoanodes allow a voltage savings of the order of 1.0 V.The photoanodes are durable and show constant output of at least 10 mA/cm2 for greater than 48 h.
- Thackeray, James W.,Natan, Michael J.,Ng, Pohleng,Wrighton, Mark S.
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- One Pot Synthesis of Dinuclear Tungsten(V) Compounds Containing 2+ (X = O, S; Y = O, S) Cores by Thermally Induced Internal Electron-Transfer Processes
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New synthetic methods for the preparation of dimeric tungsten(V) complexes are described containing the core 2+ (X = O, S; Y = O, S).The synthesized complexes have been characterized by a variety of spectroscopic techniques. has been found to react with cyanide to give
- Ansari, Mohammad A.,Chandrasekaran, Jayanthi,Sarkar, Sabyasachi
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- Aza-substitution, benzo-annulation effects and catalytic activity of β-octaphenyl-substituted tetrapyrrolic macroheterocyclic cobalt complexes. I. heterogeneous catalysis
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The influence of the size of conjugated π-system on catalytic activity of cobalt complex with β-octaphenylporphyrin and its tetraaza-, tetrabenzo and tetrabenzotetraaza derivatives was studied in present work. It is found that catalytic activity for oxidation of sulfur-containing compounds increases under extension of conjugated macrocycle system according to the following series CoP??CoBP?≤?CoPz??CoPPz???CoPc.
- Vashurin, Artur,Maizlish, Vladimir,Kuzmin, Ilya,Petrov, Oleg,Razumov, Mikhail,Pukhovskaya, Svetlana,Golubchikov, Oleg,Koifman, Oscar
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- Method for preparing tetraalkyl thiuram disulfide through photocatalytic oxidation
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The invention relates to a method for preparing tetraalkyl thiuram disulfide by photocatalytic oxidation. The method comprises the following steps: carrying out mixed reaction on secondary amine, carbon disulfide and a catalyst in a medium to generate an intermediate product; and carrying out catalytic oxidation reaction on the intermediate product under illumination to obtain tetraalkyl thiuram disulfide. According to the invention, the method is high in reaction speed and mild in condition, and energy conservation and efficiency improvement are achieved; the used medium and catalyst can be recycled, so that the resource utilization rate is improved; and the method does not produce inorganic salt by-products, and the product has high yield and high purity.
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Paragraph 0079-0086
(2021/02/13)
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- Continuous-flow step-economical synthesis of thiuram disulfidesviavisible-light photocatalytic aerobic oxidation
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A continuous-flow photocatalytic synthesis of the industrially important thiuram disulfides has been developed, utilizing O2as the oxidant and Eosin Y as the photoredox catalyst. This highly atom- and step-economical method features much reduced reaction time as well as excellent product yield and purity, making it a sustainable and potentially scalable process for industrial production.
- Xu, Hao-Xing,Zhao, Ze-Run,Patehebieke, Yeersen,Chen, Qian-Qian,Fu, Shun-Guo,Chang, Shuai-Jun,Zhang, Xu-Xu,Zhang, Zhi-Liang,Wang, Xiao
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supporting information
p. 1280 - 1285
(2021/02/26)
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- Microfluidic electrosynthesis of thiuram disulfides
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An electrolytic approach to sodium dithiocarbamates based on a microfluidic reactor is proposed for the green synthesis of thiuram disulfides, which are versatile free radical initiators. The electro-oxidation reactions avoid the over-oxidation of sodium dithiocarbamates and the generation of waste salts, which have perplexed the industry for a long time. This microfluidic electrolysis method prevents solid deposition by introducing liquid-liquid Taylor flow into the microchannel, and promotes the synthesis efficiency of thiuram disulfides with the enlargement of the electrode-specific surface area. The highest yield of thiuram disulfide was 88% in the experiment without any oxidation by-products. The Faraday efficiencies of most reactions are higher than 96%, showing the excellent electronic utilization. In addition to improving the environmental friendliness of sodium dithiocarbamate oxidation, the electrosynthesis method helps to create a cyclic technology of thiuram disulfide synthesis via the combination of sodium dithiocarbamate generation in a packed bed reactor. The cyclic technology finally achieved >99% atom utilization in thiuram disulfide synthesis from secondary amines and carbon disulfide. This journal is
- Zheng, Siyuan,Wang, Kai,Luo, Guangsheng
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supporting information
p. 582 - 591
(2021/01/28)
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- Synthesis and Properties of Metal Complexes with Octa(4-cyclohexylphenoxy)phthalocyanines
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Abstract: Phthalonitriles bearing p-cyclohexylphenoxy groups have been obtained on the basis of 4-bromo-5-nitrobenzene-1,2-dicarbonitrile and transformed into the octasubstituted cobalt and copper phthalocyanines. The obtained compounds have been characterized by spectral methods.
- Znoiko,Tolstykh,Mikhailova,Novikov,Vashurin,Maizlish
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p. 2289 - 2295
(2021/02/12)
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- Thiuram disulfide compound and synthesis process thereof
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The invention belongs to the field of rubber additives and particularly relates to a thiuram disulfide compound and a synthesis process thereof. The synthesis process comprises the following steps: (1) mixing secondary amine with alkaline liquid, then dropwise adding carbon disulfide, wherein the molar ratio of the secondary amine to the alkaline liquid to the carbon disulfide is 1 to (1-2) to (1-2), and reacting at the temperature of 30-60 DEG C to obtain a sodium dithioformate intermediate; (2) mixing and stirring the sodium dithioformate intermediate obtained in the step (1), dimethylsulfoxide and a dispersant, dropwise adding a strong acid catalyst and reacting at the temperature of 30-80 DEG C, wherein the molar ratio of the sodium dithioformate intermediate to the dimethylsulfoxide to the strong acid catalyst is 2 to (1-1.8) to (2-4), and the molar amount of the catalyst is metered by hydrogen ions; and generating a target product. The product yield of the reaction can reach 95%or above; through HPLC test of the product, the purity can reach up to 96%.
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Paragraph 0029-0032
(2019/03/25)
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- Photocatalytic H2-Evolution by Homogeneous Molybdenum Sulfide Clusters Supported by Dithiocarbamate Ligands
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Irradiation at 460 nm of [Mo3(μ3-S)(μ2-S2)3(S2CNR2)3]I ([2a]I, R = Me; [2b]I, R = Et; [2c]I, R = iBu; [2d]I, R = CH2C6H5) in a mixed aqueous-polar organic medium with [Ru(bipy)3]2+ as photosensitizer and Et3N as electron donor leads to H2 evolution. Maximum activity (300 turnovers, 3 h) is found with R = iBu in 1:9 H2O:MeCN; diminished activity is attributed to deterioration of [Ru(bipy)3]2+. Monitoring of the photolysis mixture by mass spectrometry suggests transformation of [Mo3(μ3-S)(μ2-S2)3(S2CNR2)3]+ to [Mo3(μ3-S)(μ2-S)3(S2CNR2)3]+ via extrusion of sulfur on a time scale of minutes without accumulation of the intermediate [Mo3S6(S2CNR2)3]+ or [Mo3S5(S2CNR2)3]+ species. Deliberate preparation of [Mo3S4(S2CNEt2)3]+ ([3]+) and treatment with Et2NCS21- yields [Mo3S4(S2CNEt2)4] (4), where the fourth dithiocarbamate ligand bridges one edge of the Mo3 triangle. Photolysis of 4 leads to H2 evolution but at ~25% the level observed for [Mo3S7(S2CNEt2)3]+. Early time monitoring of the photolyses shows that [Mo3S4(S2CNEt2)4] evolves H2 immediately and at constant rate, while [Mo3S7(S2CNEt2)3]+ shows a distinctive incubation prior to a more rapid H2 evolution rate. This observation implies the operation of catalysts of different identity in the two cases. Photolysis solutions of [Mo3S7(S2CNiBu2)3]+ left undisturbed over 24 h deposit the asymmetric Mo6 cluster [(iBu2NCS2)3(μ2-S2)2(μ3-S)Mo3](μ3-S)(μ3-η2,η1-S′,η1-S″-S2)[Mo3(μ2-S)3(μ3-S)(S2CNiBu2)2(μ2-S2CNiBu2)] in crystalline form, suggesting that species with this hexametallic composition and core topology are the probable H2-evolving catalysts in photolyses beginning with [Mo3S7(S2CNR2)3]+. When used as solvent, N,N-dimethylformamide (DMF) suppresses H2-evolution but to a greater degree for [Mo3S4(S2CNEt2)4] than for [Mo3S7(S2CNEt2)3]+. Recrystallization of [Mo3S4(S2CNEt2)4] from DMF affords [Mo3S4(S2CNEt2)4(η1,κO-DMF)] (5), implying that inhibition by DMF arises from competition for a Mo coordination site that is requisite for H2 evolution. Computational assessment of [Mo3S4(S2CNMe2)3]+ following addition of 2H+ and 2e- suggests a Mo(H)-μ2(SH) intermediate as the lowest energy species for H2 elimination. An analogous pathway may be available to the Mo6 cluster via dissociation of one end of the μ2-S2CNR2 ligand, a known hemilabile ligand type, in the [Mo3S4]4+ fragment.
- Fontenot, Patricia R.,Shan, Bing,Wang, Bo,Simpson, Spenser,Ragunathan, Gayathri,Greene, Angelique F.,Obanda, Antony,Hunt, Leigh Anna,Hammer, Nathan I.,Webster, Charles Edwin,Mague, Joel T.,Schmehl, Russell H.,Donahue, James P.
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p. 16458 - 16474
(2019/12/24)
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- Nucleophilic Substitution in 4-Bromo-5-nitrophthalodinitrile: XVI.1 4-(1H-Benzotriazol-1-yl)-5-[(4-carboxyphenyl)oxy/sulfanyl]- phthalonitriles and Cobalt Phthalocyanines Thereof
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A method of synthesis of 4-(1H-benzotriazol-1-yl)-5-[(4-carboxyphenyl)oxy]- and -5-[(4-carboxyphenyl) sulfanyl]phthalonitriles starting with 4-bromo-5-nitrophthalonitriles was developed. The synthesized phthalonitriles were used to prepare cobalt tetra-4-(1H-benzotriazol-1-yl)-tetra-5-[(4-carboxyphenyl)oxy/sulfanyl]phthalocyanines. The spectral and catalytic properties of the resulting octasubstituted phthalocyanines were studied.
- Znoiko,Kuz’min,Tikhomirova,Smirnov,Maizlish,Vashurin,Shaposhnikov
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p. 751 - 757
(2018/06/14)
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- Mechanistic Insight into the Photocontrolled Cationic Polymerization of Vinyl Ethers
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The mechanism of the recently reported photocontrolled cationic polymerization of vinyl ethers was investigated using a variety of catalysts and chain-transfer agents (CTAs) as well as diverse spectroscopic and electrochemical analytical techniques. Our study revealed a complex activation step characterized by one-electron oxidation of the CTA. This oxidation is followed by mesolytic cleavage of the resulting radical cation species, which leads to the generation of a reactive cation - this species initiates the polymerization of the vinyl ether monomer - and a dithiocarbamate radical that is likely in equilibrium with the corresponding thiuram disulfide dimer. Reversible addition-fragmentation type degenerative chain transfer contributes to the narrow dispersities and control over chain growth observed under these conditions. Finally, the deactivation step is contingent upon the oxidation of the reduced photocatalyst by the dithiocarbamate radical concomitant with the production of a dithiocarbamate anion that caps the polymer chain end. The fine-tuning of the electronic properties and redox potentials of the photocatalyst in both the excited and the ground states is necessary to obtain a photocontrolled system rather than simply a photoinitiated system. The elucidation of the elementary steps of this process will aid the design of new catalytic systems and their real-world applications.
- Michaudel, Quentin,Chauviré, Timothée,Kottisch, Veronika,Supej, Michael J.,Stawiasz, Katherine J.,Shen, Luxi,Zipfel, Warren R.,Abru?a, Héctor D.,Freed, Jack H.,Fors, Brett P.
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supporting information
p. 15530 - 15538
(2017/11/06)
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- Pyruvate dehydrogenase kinase inhibitor and application thereof
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The invention provides a pyruvate dehydrogenase kinase inhibitor and an application thereof, specifically a compound as shown in a formula I described in the specification or pharmaceutically acceptable salts thereof. The compound has excellent effects of inhibiting pyruvate dehydrogenase kinase activity and resisting tumors. The invention also provides a pharmaceutical composition containing the compound provided by the invention and the application thereof in the aspect of inhibiting pyruvate dehydrogenase kinase.
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Paragraph 0107; 0108; 0109; 0110; 0111; 0112; 0113; 0114
(2017/08/28)
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- Symmetrical and difunctional substituted cobalt phthalocyanines with benzoic acids fragments: Synthesis and catalytic activity
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Difunctional and symmetric phthalonitriles were synthesized by nucleophilic substitution of brome and nitro-group in 4-bromo-5-nitro-phthalonitrile for residues 4-amino-, 4-hydroxyl- and 4-sulfanyl benzoic acid. Symmetrical and difunctional substituted cobalt phthalocyanines were obtained by template synthesis based on mentioned phthalonitriles. Their spectral properties and catalytic activity in aerobic oxidation of sodium N,N-carbomoditiolate were investigated.
- Vashurin, Artur,Maizlish, Vladimir,Kuzmin, Ilya,Znoyko, Serafima,Morozova, Anastasiya,Razumov, Mikhail,Koifman, Oscar
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- Novel Co(II) phthalocyanines of extended periphery and their water-soluble derivatives. Synthesis, spectral properties and catalytic activity
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Novel complexes of cobalt and copper with substituted phthalocyanines were synthesized and characterized. Their water-soluble derivatives were obtained by sulfonation under mild conditions and structurally proved. Aggregation equilibrium in water mediums was shown and influence of geometrical and electron parameters of macroheterocycle peripheral substituents on these processes was established. Catalytic activity upon liquid-phase oxidation of N,N-diethylcarbamodithiolate to thiuram E was studied. Kinetic parameters of substrate oxidation in presence of cobalt phthalocyanines were considered.
- Filippova, Anna,Vashurin, Artur,Znoyko, Serafima,Kuzmin, Ilya,Razumov, Mikhail,Chernova, Alena,Shaposhnikov, Gennady,Koifman, Oscar
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- 3,6-Di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) mediated metal-free mild oxidation of thiols to disulfides in aqueous medium
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Thiols are efficiently oxidized to disulfides (RSSR) in the presence of 3,6-di(pyridin-2-yl)-1,2,4,5-tetrazine (pytz) in aqueous medium, as well as in the absence of a solvent under mild and metal-free conditions. A broad range of alkyl, aryl and heterocyclic symmetrical disulfides can be easily obtained in almost quantitative yields. The X-ray single crystal structure of 2-aminocyclopent-1-ene-1-carbothioic dithioperoxyanhydride (disulfide obtained from 2-aminocyclopentene-1-dithiocarboxylic acid, ACDA) is reported. The reaction mechanism has been studied thoroughly. It is shown that the reaction proceeds through the formation of an organosulphur radical. Pytz interacts with thiol to accept one electron and produces an organosulphur radical. Pytz ultimately accepts two electrons to form H2pytz and is capable of oxidizing 2 equivalents of thiols.
- Samanta, Suvendu,Ray, Shounak,Ghosh, Abhisek Brata,Biswas, Papu
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p. 39356 - 39363
(2016/06/01)
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- Coupling of gem-difluorinated organozinc reagents with S-electrophiles
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gem-Difluorinated organozinc reagents, which were prepared by insertion of CF2-fragment into C[sbnd]Zn bond, couple with diethyl dixanthogen, di(benzothiazolyl) disulfide, and tetraethylthiuram disulfide. The reaction is promoted either by a copper(I) catalyst or by irradiation with blue light in the presence of Eosin Y disodium salt.
- Ashirbaev, Salavat S.,Levin, Vitalij V.,Struchkova, Marina I.,Dilman, Alexander D.
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p. 143 - 148
(2016/10/24)
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- Metal-Free Photocatalytic Aerobic Oxidation of Thiols to Disulfides in Batch and Continuous-Flow
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Disulfides represent significant molecular and structural features in various biologically active compounds and fine chemicals. Therefore, the development of mild, efficient and sustainable methods to access disulfides is of great importance. Here, we describe the development of a mild metal-free photocatalytic aerobic oxidation of thiols to disulfides using Eosin Y and visible-light irradiation. A continuous flow procedure was developed to accelerate the photocatalytic process, enabling the preparation of disulfides with high purity in a timeframe of minutes. The mildness and applicability of our method was exemplified by the flow synthesis of the cyclic peptide hormone, oxytocin, requiring only a 200s reaction time and an efficient one-pot batch protocol for the preparation of the therapeutic thiuram disulfide, disulfiram.
- Talla, Ali,Driessen, Brian,Straathof, Natan J. W.,Milroy, Lech-Gustav,Brunsveld, Luc,Hessel, Volker,No?l, Timothy
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supporting information
p. 2180 - 2186
(2015/07/27)
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- Sulfonated Co(II) phthalocyanines covalently anchored at organic polymers as catalyst for mild oxidation of mercaptans
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Current work is devoted to covalent immobilization of sulfonated derivatives of cobalt phthalocyanines "Merox catalysts" on the surfaces of polypropylene and polyethylene terephthalate. Their catalytic activity in reaction of mild oxidation of sulfur compounds to disulfides with oxygen of the air was studied. Anchoring of the catalyst on this polymer prevents its leaching and promotes its efficient recovering and recycling without significant loss of catalytic activity.
- Vashurin, Artur,Kuzmin, Ilya,Razumov, Mikhail,Pukhovskaya, Svetlana,Golubchikov, Oleg,Voronina, Alena,Shaposhnikov, Gennady,Koifman, Oscar
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p. 1159 - 1167
(2016/02/03)
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- Novel aqueous soluble cobalt(II) phthalocyanines of tetracarboxyl-substituted: Synthesis and catalytic activity on oxidation of sodium diethyldithiocarbamate
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Enhancement of the catalytic activity of phthalocyanine catalysts by immobilizing them on polymer matrix has been studied. It has been found that the immobilization of cobalt(II) phthalocyanines on polymers enhances their catalytic activity in the oxidation of sodium diethyldithiocarbamate by air oxygen under mild conditions.
- Vashurin, Artur,Maizlish, Vladimir,Pukhovskaya, Svetlana,Voronina, Alena,Kuzmin, Ilya,Futerman, Natalya,Golubchikov, Oleg,Koifman, Oskar
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p. 573 - 581
(2015/05/05)
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- Cerium ammonium nitrate-catalyzed aerobic oxidative coupling of dithiocarbamates: Facile synthesis of thioureas and bis(aminothiocarbonyl)disulfides
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Diverse disubstituted and trisubstituted thioureas were synthesized by the condensation of dithiocarbamate TEA (or DABCO) salts and amines using cerium ammonium nitrate (CAN) as a catalyst in high yields at room temperature. It is a one-pot method and it is unnecessary to isolate isothiocyanates. This reaction probably took place through nucleophilic addition of amines to isothiocyanates, which were generated by oxidative coupling of dithiocarbamates and the following decomposition of bis(aminothiocarbonyl)disulfides. When secondary amines and CS2served as the reactants, bis(aminothiocarbonyl)disulfides were obtained via tandem nucleophilic addition/oxidative coupling reactions in moderate to excellent yields. In all the coupling reactions, the oxidant was air and CAN possibly acted as an SET catalyst.
- Li, Tian-Tian,Song, Xiang-Hai,Wang, Mei-Shuang,Ma, Ning
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p. 40054 - 40060
(2014/12/10)
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- Reduced graphene oxide as recyclable catalyst for synthesis of Bis(aminothiocarbonyl)disulfides from secondary amines and carbon disulfide
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The reaction of secondary amines with CS2 under mild conditions using reduced graphene oxide (rGO) as a green catalyst was reported, which provided an efficient access to the one-pot synthesis of bis(aminothiocarbonyl) disulfides. The rGO can be recycled at least four times without any loss of catalytic activity. A plausible mechanism was proposed.
- Wang, Meishuang,Song, Xianghai,Ma, Ning
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p. 1233 - 1239
(2014/07/21)
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- Development of an improved method for conversion of thiuram disulfides into N,N-dialkylcarbamoyl halides and derivatives
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A convenient procedure for preparing N,N-disubstituted carbamoyl halides is reported. It consists of two steps: (1) reaction of carbon disulfide and a secondary amine in the presence of a polar organic solvent and oxygen to produce the corresponding tetraalkyl thiuram disulfides and (2) reaction of tetraalkyl thiuram disulfide with a halide in the presence of an aprotic organic solvent to produce the corresponding N,N-disubstituted carbamoyl halide. Copyright Taylor & Francis Group, LLC.
- Adeppa,Rupainwar,Misra, Krishna
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experimental part
p. 285 - 290
(2011/03/20)
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- Bis(dialkylaminethiocarbonyl)disulfides as potent and selective monoglyceride lipase inhibitors
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Monoglyceride lipase (MGL) inhibition may offer an approach in treating diseases in which higher 2-arachidonoyglycerol activity would be beneficial. We report here the synthesis and pharmacological evaluation of bis(dialkylaminethiocarbonyl)disulfide derivatives as irreversible MGL inhibitors. Inhibition occurs through interactions with MGL C208 and C242 residues, and these derivatives exhibit high inhibition selectivity over fatty acid amide hydrolase, another endocannabinoid-hydrolyzing enzyme. 2009 American Chemical Society.
- Kapanda, Coco N.,Muccioli, Giulio G.,Labar, Geoffray,Poupaert, Jacques H.,Lambert, Didier M.
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experimental part
p. 7310 - 7314
(2010/07/14)
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- METHOD FOR PREPARING ALKOXYAMINES BY PHOTOLYSIS OF DITHIOCARBAMATES
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The present invention relates to a novel process for preparing alkoxyamines from a nitroxide and a dithiocarbamate by photolysis reaction. This process, which does not generate effluent containing metals, may be carried out in batch or in continuous mode and takes place at a lower temperature than the known processes for synthesizing alkoxyamines.
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Page/Page column 3
(2009/09/08)
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- Carbon tetrabromide promoted reaction of amines with carbon disulfide: Facile and efficient synthesis of thioureas and thiuram disulfides
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A novel carbon tetrabromide promoted one-pot reaction of amines and carbon disulfide under mild conditions has been developed, which provides a straightforward and efficient access to thioureas and thiuram disufides, depending on the nature of the amines employed. The promotion effect is explained as the transient formation of a sulfenyl bromide intermediate from dithiocarbamate and carbon tetrabromide during the reaction. Georg Thieme Verlag Stuttgart · New York.
- Liang, Fushun,Tan, Jing,Piao, Chengri,Liu, Qun
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experimental part
p. 3579 - 3584
(2009/07/04)
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- Combinations for the treatment of fungal infections
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The invention features methods and compositions for treating a patient diagnosed with, or at risk for developing, a fungal infection.
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- A short, novel, and cheaper procedure for oligonucleotide synthesis using automated solid phase synthesizer
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Dimethylthiuram disulfide (DTD) has been developed as an efficient thiolation reagent during automated synthesis of oligonucleotides using phosphoramidite chemistry. Simultaneous thiolation and capping was accomplished by mixing DTD with capping solution B, which saved 20% of solvent consumption and compressed the four-step synthesis cycle to three. Large-scale (1 mmol) synthesis of phosphorothioate oligonucleotides has been demonstrated with excellent yield and purity.
- Song, Quanlai,Wang, Zhiwei,Sanghvi, Yogesh S.
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p. 629 - 633
(2007/10/03)
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- Trimethylchlorosilane (TMSCl) and cyanuric chloride (CC) catalyzed efficient oxidative coupling of thiols with dimethylsulfoxide
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Different types of thiols were rapidly and efficiently converted to disulfides using DMSO in the presence of catalytic amounts of either trimethylchlorosilane (TMSCl) or cyanuric chloride (CC).
- Karimi, Babak,Hazarkhani, Hassan,Zareyee, Daryoush
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p. 2513 - 2516
(2007/10/03)
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- Catalytic oxidation of thiols to disulfides with vanadyl acetylacetonate (VO(ACAC)2)
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Catalytic amounts of VO(acac)2 coupled with t-butylhydroperoxide chemoselectively oxidizes thiols to disulfides under mild reaction conditions and is generally useful for a wide variety of thiols.
- Raghavan,Rajender,Joseph,Rasheed
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p. 1477 - 1480
(2007/10/03)
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- Photoreduction of IrCl62- complex in alcohol solutions and its reaction with hydroxyalkyl radicals
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The photochemistry of IrCl62- complex in simple alcohols have been studied using laser-flash photolysis. Single electron transfer from the solvent molecule to the light-excited complex has been shown to be the primary photochemical process, Quantum yields of the photoreduction of IrCl62- complex and the rate constants of its reaction with hydroxyalkyl radicals were determined at 200-330 K. Deviations of the rate constants from Debye-Smoluchowski equation for diffusion-controlled reactions are discussed. 1998 John Wiley & Sons, Inc.
- Glebov,Plyusnin,Grivin,Ivanov,Tkachenko,Lemmetyinen
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p. 711 - 719
(2007/10/03)
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- A convenient synthesis of disulfides and sulfenamides
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We report the synthesis of disulfides from thiols through the use of morpholine-iodine complex.The method is yet another procedure for the preparation of the title compounds.
- Ramadas, Krishnamurthy,Srinivasan, Natarajan
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p. 4179 - 4184
(2007/10/03)
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- Sodium chlorite - Yet another oxidant for thiols to disulphides
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An efficicient oxidative coupling of thiols to disulphides is described using sodium chlorite which has good synthetic and commercial relevance.
- Ramadas,Srinivasan
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p. 227 - 234
(2007/10/02)
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- Electrocatalytic Oxidation of Thiols on a TEMPO Modified Electrode
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Monothiols were oxidized efficiently and quantitatively to disulfides on graphite felt electrode coated with 4-amino-2,2,6,6-tetramethylpiperidinyl-1-oxyl (4-amino-TEMPO).The 4-amino-TEMPO was immobilized through an amide linkage with poly(acrylic acid).The poly(acrylic acid) was crosslinked with 1,6-diaminohexane, and the residual carboxyl groups were methylated with diazomethane.The electrode was stable and could be used repeatedly.
- Kashiwagi, Yoshitomo,Ohsawa, Akio,Osa, Tetsuo,Ma, Zhenkun,Bobbitt, James M.
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p. 581 - 584
(2007/10/02)
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- OXIDATION OF DERIVATIVES OF DITHIOCARBAMIC ACID WITH NITROUS ACID
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The oxidation of derivatives of dithiocarbamic acid with nitrous acid was studied.Analysis of the kinetic relations showed that the rate-determining step of the reaction is the formation of the nitrosyl cation.
- Shavetov, V. A.,Zolotov, A. N.,Mokrushin, V. S.
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p. 739 - 742
(2007/10/02)
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- The Oxidation of Dithiocarbamate Anion by Substitution Inert Metal Complexes
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The kinetics of oxidation of dithiocarbamate anions to thiuram disulfides in aqueous acetone by 3- and 11 other substitution inert metal complexes have been investigated.Outer-sphere electron transfer, resulting in the formation of dithiocarbamate thio radicals, is the rate determining step.A Marcus cross reaction treatment allows an estimate for the redox potential for the dithiocarbamate radical/anion couple.For diethyldithiocarbamate, Edeg(edtc./edtc-) = 425+/-33 mV ν.s.c.e. and the outer-sphere electron self-exchange rate constant is logkex = 7.0+/-0.3.A comparison with thiophenolate oxidation is also given.
- Nichols, Peter J.,Grant, Michael W.
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p. 1085 - 1102
(2007/10/02)
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- PREPARATION AND REACTIONS OF NOVEL μ-OXO-BISANTIMONY AMINOALKOXIDE
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Novel μ-oxo-bis(diphenylhydroxyantimony) di (1) was obtained in the reaction of triphenylstibine oxide and 2-(methylamino)ethanol.Cyclic urethane derivatives were obtained by the reaction of 1 with CO2 or CS2 in good yields.
- Nomura, Ryoki,Kori, Masakuni,Matsuda, Haruo
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p. 579 - 580
(2007/10/02)
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- Process for the preparation of thiuram disulfides
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A process for the preparation of thiuram disulfides substituted with aliphatic cycloaliphatic, araliphatic, or aromatic hydrocarbon radicals, said process comprising reacting a suitably substituted secondary amine having a pKa ≥8 with carbon disulfide in a solvent and in the presence of oxygen or oxygen-containing gas, a solvent, and a metalliferous catalyst, at a temperature of between 0° C. and 200° C.
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- Process for the preparation of thiuram disulfides
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A process for the preparation of thiuram disulfides substituted with aliphatic, cycloaliphatic, araliphatic, or aromatic hydrocarbon radicals, said process comprising reacting a suitably substituted secondary amine with carbon disulfide and in the presence of a tertiary amine or ammonia, oxygen or oxygen-containing gas, a solvent, and a metalliferous catalyst, at a temperature of between 0° C. and 200° C.
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- Reduction Potentials of Thiuram Disulfide/Dithiocarbamate Couples in Acetone/Water
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Reduction potentials relative to the saturated calomel electrode, Eo, of a series of thiuram disulfide/dithiocarbamate couples have been measured in 30percent v/v water in acetone and at μ 0.2 mol l-1 (NaNO3) by a combination of potentiometric measurements and equilibrium constant determinations for thiolate/disulfide interchange reactions.Eo values lie in the range -250 to -340 mV which place dithiocarbamates as intermediate between thiophenolate (Eo -540 mV) and ethylxanthate (Eo -206 mV) in reducing properties.The significant effect on Eo of varying the substituents on the nitrogen in the dithiocarbamates correlates with the substituent effects on the acid dissociation constants of the parent dithiocarbamic acid and with trends in the half-wave potentials for metal-based oxidation and reduction of transition metal dithiocarbamate complexes.
- Nichols, Peter J.,Grant, Michael W.
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p. 2455 - 2463
(2007/10/02)
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