127-09-3Relevant articles and documents
Depree,Closson
, p. 2311 (1958)
A new, more efficient procedure for the preparation of potassium tris(malonto)cobaltate(III) dihydrate
Miodragovic, Zoran M.,Vuckovic, Gordana
, p. 1451 - 1461 (1999)
A new, very efficient and elegant procedure for the preparation of potassium tris(malonato)cobaltate(III) dihydrate, starting from Co(OH)3 and potassium hydrogenmalonate, is presented. The most important advantages of this procedure, in comparison to the previously reported ones, are: a relatively short time required, saving of the reagents and solvents, and a very good yield of pure product. The identification of the obtained complex was carried out by elemental analyses, electronic absorption and IR spectroscopy. The spectral data are in accordance with the previously reported literature data. Analogous procedure was also preliminary tested for the preparation of the corresponding tris(oxalato)-and tris(succinato)cobaltate(III). Finally, the described complex can be used as a starting material for the preparation of one mixed ligand Co(III) complex.
Efficient Iridium Catalysts for Formic Acid Dehydrogenation: Investigating the Electronic Effect on the Elementary β-Hydride Elimination and Hydrogen Formation Steps
Liu, Hong,Wang, Wan-Hui,Xiong, Huatian,Nijamudheen,Ertem, Mehmed Z.,Wang, Mei,Duan, Lele
, p. 3410 - 3417 (2021)
We report herein a series of Cp*Ir complexes containing a rigid 8-aminoquinolinesulfonamide moiety as highly efficient catalysts for the dehydrogenation of formic acid (FA). The complex [Cp*Ir(L)Cl] (HL = N-(quinolin-8-yl)benzenesulfonamide) displayed a high turnover frequency (TOF) of 2.97 × 104 h-1 and a good stability (>100 h) at 60 °C. Comparative studies of [Cp*Ir(L)Cl] with the rigid ligand and [Cp*Ir(L′)Cl] (HL′ = N-propylpypridine-2-sulfonamide) without the rigid aminoquinoline moiety demonstrated that the 8-aminoquinoline moiety could dramatically enhance the stability of the catalyst. The electron-donating ability of the N,N′-chelating ligand was tuned by functionalizing the phenyl group of the L ligand with OMe, Cl, and CF3 to have a systematical perturbation of the electronic structure of [Cp*Ir(L)Cl]. Experimental kinetic studies and density functional theory (DFT) calculations on this series of Cp*Ir complexes revealed that (i) the electron-donating groups enhance the hydrogen formation step while slowing down the β-hydride elimination and (ii) the electron-withdrawing groups display the opposite effect on these reaction steps, which in turn leads to lower optimum pH for catalytic activity compared to the electron-donating groups.
Synthesis and characterization of complexes of some hydroxyaryltellurium trichlorides with N-donor ligands
Verma,Dahiya, Reena,Soni, Daya
, p. 1033 - 1052 (1999)
Twenty new complexes of hydroxyaryltellurium trichlorides derived from isomeric cresols and ortho-chlorophenol with pyridine (Py), 2,2′-bipyridyl (Bipy) and piperidine (Pip) have been synthesized and characterized by elemental analyses, conductance, cryoscopy, infrared and proton magnetic resonance studies. Pyridine and piperidine form RTeCl3.L and RTeCl3.2L complexes, whereas 2,2′-bipyridyl which acts as a bidentate ligand and gives only RTeCl3.L complexes. Conductance and cryoscopic measurements reflect their weak or 1:1 electrolytic behaviour in solution of nitrobenzene, acetonitrile and acetone. Spectral studies indicate the linkage of these ligand molecules to the tellurium atom of the hydroxyaryltellurium group through nitrogen atoms. A square-pyramidal structure is suggested for RTeCl3.Py and RTeCl3.Pip, whereas 1:2 complexes of pyridine and piperidine along with RTeCl3.Bipy, have octahedral stereochemistry.
Interaction of cobalt(II) and copper(II) with polyoxometallates. Structure of Na3Co[IMo6O24]. 14H2O
Rosu, Cristina,Gomez-Garcia, Carlos Jose,Dickman, Michael H.,Rusu, Mariana
, p. 1123 - 1131 (1999)
Cobalt(II) and copper(II) complexes with the ligand anion [IMo6O24]5- (periodate 6-molybdoanion) of the general formula Na3M[IMo6O24].nH2O (where M = Co, Cu) have been prepared by the reaction of the corresponding metal salts with the ligand in aqueous media (pH = 6). The complexes were characterised by elemental and thermogravimetric analyses, spectral data (IR, UV-vis). The EPR spectrum of a copper(II) powder sample was recorded at both room temperature and 12 K indicating a weakly distorted octahedral copper(II) stereochemistry. The crystal structure of Na3CO[IMo6O24]. 14H2O has been determined by single-crystal X-ray diffraction technique.
Seyb, E.,Kleinberg, J.
, p. 115 - 117 (1951)
Selective formation of lactate by oxidation of 1,2-propanediol using gold palladium alloy supported nanocrystals
Dimitratos, Nikolaos,Lopez-Sanchez, Jose Antonio,Meenakshisundaram, Sankar,Anthonykutty, Jinto Manjaly,Brett, Gemma,Carley, Albert F.,Taylor, Stuart H.,Knight, David W.,Hutchings, Graham J.
, p. 1209 - 1216 (2009)
The use of bio-renewable resources, such as glycerol, a by-product from bio-diesel manufacture, can provide a viable way to make valuable products using greener technology. In particular, glycerol can be reduced to give 1,2-propanediol that can then be se
Carrol
, p. 143 (1918)
Beck
, p. 155 (1937)
No contribution of an inductive effect to secondary deuterium isotope effects on acidity
Perrin, Charles L.,Flach, Agnes
, p. 7674 - 7676 (2011)
Effect and cause: Secondary deuterium isotope effects on the acidity of the deuterated compounds 1-4 were measured by using an NMR titration method applicable to a mixture and capable of very high accuracy. Variable-temperature experiments show that these isotope effects are due only to changes in vibrational frequencies. These findings refute an inductive origin for these isotope effects. Copyright
MECHANISM OF CHLORAMINE-T OXIDATION OF METHYL VINYL KETONE AND ISOPROPYL METHYL KETONE IN AQUEOUS ALKALINE MEDIA
Singh, Bharat,Samant, A. K.,Saxena, B. B. L.
, p. 2591 - 2594 (1982)
The oxidation kinetics of methyl vinyl ketone and isopropyl methyl ketone by chloramine-T in aqueous alkaline solutions show first-order dependence on chloramine-T, both substrates and alkali.No effect of p-toluenesulphonamide was evident.Observed stoichiometry, negligible effect of ionic strength and a positive dielectric effect point to a mechanism involving interaction of enolate anions with chloramine-T in the rate determining step.Activation parameters and the isolation of the product formaldehyde are in agreement with the proposed mechanism.
Photoluminescence as a valuable tool in the optical characterization of acetaminophen and the monitoring of its photodegradation reactions
Baibarac, Mihaela,Daescu, Monica,Ion, Alina C.,Matea, Adelina,Negrila, Catalin,Serbschi, Constantin
, (2020/10/22)
In this work, new evidence for the photodegradation reactions of acetaminophen (AC) is reported by photoluminescence (PL), Raman scattering and FTIR spectroscopy. Under excitation wavelength of 320 nm, AC shows a PL band in the spectral range of 340–550 nm, whose intensity decreases by exposure to UV light. The chemical interaction of AC with the NaOH solutions, having the concentration ranging between 0.001 and 0.3 M, induces a gradual enhancement of the photoluminescence excitation (PLE) and PL spectra, when the exposure time of samples at the UV light increases until 140 min, as a result of the formation of p-aminophenol and sodium acetate. This behavior is not influenced by the excipients or other active compounds in pharmaceutical products as demonstrated by PLE and PL studies. Experimental arguments for the obtaining of p-aminophenol and sodium acetate, when AC has interacted with NaOH, are shown by Raman scattering and FTIR spectroscopy.
Br?nsted and Lewis Base Behavior of Sodium Amidotrihydridoborate (NaNH2BH3)
Chen, Xi-Meng,Li, Huizhen,Yang, Qiu-Yu,Wang, Rui-Rui,Hamilton, Ewan J. M.,Zhang, Jie,Chen, Xuenian
, p. 4541 - 4545 (2017/09/28)
The reactivity of sodium amidoborane (NaNH2BH3) as a Br?nsted and Lewis base was studied systematically. The [NH2BH3]– anion can act as a proton acceptor or a hydride donor in different types of reactions. In reactions with very weak Br?nsted acids such as cyclopentadiene, ammonia, and pyrazole, the [NH2BH3]– anion acts as a proton acceptor through the lone pair on N. The reactions of [NH2BH3]– with stronger Br?nsted acids are complicated. In the reaction with ammonium chloride or acetic acid, [NH2BH3]– accepts a proton, reforming NH3BH3. However, in the reaction with HCl or methanol, N–B bond cleavage occurs. [NH2BH3]– can also donate hydride in some reactions. The possible mechanisms of these reactions are discussed.