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Emília Valena Ferreira de Arago Luca Mancini Noelia Faginas-Lago Marzio Rosi Dimitrios Skouteris Fernando Pirani 《Molecules (Basel, Switzerland)》2022,27(7)
The reaction between the cyano radical CN and cyanoacetylene molecule HCN is of great interest in different astronomical fields, from star-forming regions to planetary atmospheres. In this work, we present a new synergistic theoretical approach for the derivation of the rate coefficient for gas phase neutral-neutral reactions. Statistic RRKM calculations on the Potential Energy Surface are coupled with a semiempirical analysis of the initial bimolecular interaction. The value of the rate coefficient for the HCN + CN → H + NCCCCN reaction obtained with this method is compared with previous theoretical and experimental investigations, showing strengths and weaknesses of the new presented approach. 相似文献
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Roberto Ballini Noelia Araújo Bazn Giovanna Bosica Alessandro Palmieri 《Tetrahedron letters》2008,49(24):3865-3867
A variety of primary and secondary amines give the conjugate reaction with β-nitroacrylates, via an anti-Michael addition, without any catalyst and/or solvent, allowing good yields of β-nitro-α-amino esters. 相似文献
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Elena Gómez Noelia Calvar Ángeles Domínguez Eugénia A. Macedo 《The Journal of chemical thermodynamics》2010,42(11):1324-1329
In this paper, the ionic liquids 1,2-diethylpyridinium ethylsulfate, EEpyESO4; 1-methylpyridinium methylsulfate, MpyMSO4; 1,3-dimethylpyridinium methylsulfate, MMpyMSO4; and 2-ethyl-1-methylpyridinium methylsulfate, EMpyMSO4; were synthesized in our laboratory, and their experimental densities, speeds of sound, dynamic viscosities, and refractive indices were studied as a function of temperature at atmospheric pressure. Thermal expansion coefficient, molar volume, and molar refraction of these ionic liquids were calculated from the experimental density and refractive index values. 相似文献
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Fast Exfoliation and Functionalisation of Two‐Dimensional Crystalline Carbon Nitride by Framework Charging 下载免费PDF全文
Dr. Jingjing Jia Dr. Edward R. White Dr. Adam J. Clancy Dr. Noelia Rubio Theo Suter Dr. Thomas S. Miller Kit McColl Prof. Paul F. McMillan Dr. Veronika Brázdová Prof. Furio Corà Dr. Christopher A. Howard Robert V. Law Dr. Cecilia Mattevi Prof. Milo S. P. Shaffer 《Angewandte Chemie (International ed. in English)》2018,57(39):12656-12660
Two‐dimensional (2D) layered graphitic carbon nitride (gCN) nanosheets offer intriguing electronic and chemical properties. However, the exfoliation and functionalisation of gCN for specific applications remain challenging. We report a scalable one‐pot reductive method to produce solutions of single‐ and few‐layer 2D gCN nanosheets with excellent stability in a high mass yield (35 %) from polytriazine imide. High‐resolution imaging confirmed the intact crystalline structure and identified an AB stacking for gCN layers. The charge allows deliberate organic functionalisation of dissolved gCN, providing a general route to adjust their properties. 相似文献
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A systematic study on phase behavior of the mixture of nonionic surfactants with alcohols at 30.0+/-0.1 degrees C was carried out. The total surfactant concentration was kept to 0.1 M varying the mole ratio of n-octyl beta-d-glucopyranoside (OG) and tetraethylene glycol monododecyl ether. Two uniphasic regions were found, the lamellar phase at low OG mole fraction and micelles at high OG mole fraction. The presence of OG favors the lamellae-micelle transition. Alkanols and benzyl alcohol were used as cosurfactants. The more hydrophobic alcohols (octanol and decanol) increase the OG content in the mixed bilayers. On the contrary, benzyl alcohol is not as favorable to the OG incorporation in the lamellar phase as in the mixed micelles. The L(3) phase has only been found as a uniphasic region with hexanol. 相似文献
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Fondo M García-Deibe AM Ocampo N Sanmartin J Bermejo MR 《Dalton transactions (Cambridge, England : 2003)》2004,(14):2135-2141
The heptadentate Schiff base H(3)L can react with zinc acetate to form the discrete dinuclear complex Zn(2)L(OAc)(H(2)O), 1.H(2)O. The reaction of 1.H(2)O with NMe(4)OH.5H(2)O both in air and under an argon stream has been investigated. On one hand, this reaction in air yields the tetranuclear complex (Zn(2)L)(2)(CO(3))(H(2)O)(6), 2.5H(2)O, by spontaneous absorption of adventitious carbon dioxide. This process can be reverted in an acetic acid medium, whereas the treatment of 2.5H(2)O with methanoic acid yields crystals of [Zn(2)L(HCOO)].0.5MeCN.1.25MeOH.2H(2)O, 3.0.5MeCN.1.25MeOH.2H(2)O. On the other hand, the interaction under an argon atmosphere of 1.H(2)O with NMe(4)OH.5H(2)O in methanol allows the isolation of the dinuclear complex Zn(2)L(OMe)(H(2)O)(4), 4.4H(2)O. Recrystallisations of 1.H(2)O, 2.5H(2)O and 4.4H(2)O, in different solvents, yielded single crystals of 1.MeCN.2.5H(2)O, 2.4MeOH and 4.3MeOH.H(2)O, respectively. The crystal structure of 2.4MeOH can be understood as resulting from an unusual asymmetric tetranuclear self-assembly from two dinuclear units, and shows three different geometries around the four zinc atoms. 相似文献
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Hill JP Subbaiyan NK D'Souza F Xie Y Sahu S Sanchez-Ballester NM Richards GJ Mori T Ariga K 《Chemical communications (Cambridge, England)》2012,48(33):3951-3953
Tetrapyrazinoporphyrazine substituted at its periphery with eight antioxidant 3,5-di-t-butyl-4-hydroxyphenyl groups behaves as a turn-on fluorescent sensor for fluoride anions. Conversely, the precursor antioxidant-substituted 1,2-phthalonitrile was found to act in turn-off mode suggesting that the origin of the phenomenon lies at the phenolate-substituted 1,4-pyrazinyl moiety. 相似文献
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The high-pressure asymmetric Diels-Alder reactions of d-galacto- (1a) and d-manno-3,4,5,6,7-penta-O-acetyl-1,2-dideoxy-1-nitrohept-1-enitol (1b) with 2,5-dimethylfuran (2) afforded mixtures of cycloadducts, from which the (2S,3R)-3-exo-nitro (3a and 3b), (2R,3S)-3-exo-nitro (4a and 4b), and (2R,3S)-1′,2′,3′,4′,5′-penta-O-acetyl-1′-C-(1,4-dimethyl-3-endo-nitro-7-oxabicyclo[2.2.1]hept-5-en-2-exo-yl)-d-galacto-pentitol (5b) were isolated pure. Deacetylation of these compounds led to new chiral mono-, bi-, and tricyclic ethers, being their asymmetric centers arising from the chiral inductor used in the cycloaddition reaction. A ring opening mechanism through a 1-nitro-1,3-cyclohexadiene intermediate has been proposed. 相似文献