C:Corrosive;
110-91-8Relevant articles and documents
Selective electrochemical deprotection of cinnamyl ethers, esters, and carbamates
Hansen, Jeff,Freeman, Stanley,Hudlicky, Tomas
, p. 1575 - 1578 (2003)
Electrochemical deprotection of the cinnamyl moiety from ethers, esters, and carbamates was studied with the focus on O- versus N- selectivity as well as selectivity over allyl or benzyl systems.
EXAMINATION OF HIGH-LOADED NICKEL CATALYSTS BY IR SPECTROSCOPY: EFFECT OF THE SUPPORT AND Pd ON SURFACE PROPERTIES
Jiratova, Kveta,Moravkova, Lenka,Snajdaufova, Hana,Paukshtis, Evgenii A.
, p. 2575 - 2582 (1992)
Activation of the ammonia molecule and subsequent adsorption of the NH2 fragment on the surface of the NiO + Pd/TiO2 catalysts, in contrast to NiO + PdSiO2 catalysts, was demonstrated by IR spectroscopy.The decrease in the NiO + Pd/TiO2 catalyst acidity was manifested in the higher catalyst stability in reductive amination of diethylene glycol to morpholine.
Manganese-Catalyzed Sequential Hydrogenation of CO2 to Methanol via Formamide
Kar, Sayan,Goeppert, Alain,Kothandaraman, Jotheeswari,Prakash, G. K. Surya
, p. 6347 - 6351 (2017)
Mn(I)-PNP pincer catalyzed sequential one-pot homogeneous CO2 hydrogenation to CH3OH by molecular H2 is demonstrated. The hydrogenation consists of two parts - N-formylation of an amine utilizing CO2 and H2, and subsequent formamide reduction to CH3OH, regenerating the amine in the process. A reported air-stable and well-defined Mn-PNP pincer complex was found active for the catalysis of both steps. CH3OH yields up to 84% and 71% (w.r.t amine) were obtained, when benzylamine and morpholine were used as amines, respectively; and a TON of up to 36 was observed. In our opinion, this study represents an important development in the nascent field of base-metal-catalyzed homogeneous CO2 hydrogenation to CH3OH.
Experimental investigations of thermal stability of some morpholinecarbamic acid complexes of copper(II) and zinc(II)
Kalia, Shashi B.,Kumar, Rajesh,Bharti, Monika,Christopher
, p. 1291 - 1306 (2017)
Some new carbamates, viz. M(MorphcbmH)2X2 (MorphcbmH?=?morpholinecarbamic acid, M?=?Cu, X?=?Cl, ClO4,NO3; M?=?Zn, X?=?Cl, ClO4, NO3, CH3COO and X2?=?SO4), h
On-resin N-terminal peptoid degradation: Toward mild sequencing conditions
Proulx, Caroline,No?, Falko,Yoo, Stan,Connolly, Michael D.,Zuckermann, Ronald N.
, p. 726 - 736 (2016)
A novel approach to sequentially degrade peptoid N-terminal N-(substituted)glycine residues on the solid-phase using very mild conditions is reported. This method relies on the treatment of resin-bound, bromoacetylated peptoids with silver perchlorate in THF, leading to an intramolecular cyclization reaction to liberate the terminal residue as a N-substituted morpholine-2,5-dione, resulting in a truncated peptoid upon hydrolysis and a silver bromide byproduct. Side-chain functional group tolerance is explored and reaction kinetics are determined. In a series of pentapeptoids possessing variable, non-nucleophilic side-chains at the second position (R2), we demonstrate that sequential N-terminal degradation of the first two residues proceeds in 87% and 74% conversions on average, respectively. We further demonstrate that the degradation reaction is selective for peptoids, and represents substantial progress toward a mild, iterative sequencing method for peptoid oligomers.
Kinetics and mechanism of large rate enhancement in an acidic aqueous cleavage of the tertiary amide bond of N-(2-methoxyphenyl)-N′-morpholinophthalamide (1)
Sim, Yoke-Leng,Ariffin, Azhar,Khan, M. Niyaz
, p. 178 - 182 (2008)
The rate of conversion of 1 to N-(2-methoxyphenyl)phthalimide (2) within [HCl] range 5.0 × 10-3-1.0 M at 1.0 M ionic strength (by NaCl) reveals the presence of both uncatalyzed and specific acid-catalyzed kinetic terms in the rate law. Intramolecular carboxamide group-assisted cleavage of amide bond of 1 reveals rate enhancement of much larger than 106-fold compared to the expected rate of analogous intermolecular reaction.
New Allyl Group Acceptors for Palladium Catalyzed Removal of Allylic Protections and Transacylation of Allyl Carbamates.
Dessolin, Michele,Guillerez, Marie-George,Thieriet, Nathalie,Guibe, Francois,Loffet, Albert
, p. 5741 - 5744 (1995)
Key words: allylic protecting groups, palladium catalysis, transacylation, phenyltrihydrosilane, N-methyl-N-(trimethylsilyl)trifluoroacetamide.Allyl carboxylates, carbamates and phenoxides may be cleaved or transacylated in the presence of palladium catalyst and either phenyltrihydridosilane or N-methyl-N-(trimethylsilyl)trifluoroacetamide.These reactions are totally compatible with the presence of Boc and, as far as phenyltrihydrosilane is concerned, Fmoc protections.
Infrared studies of amine, pyridine, and phosphine derivatives of tungsten hexacarbonyl
Angelici, Robert J.,Malone, Mary Diana
, p. 1731 - 1736 (1967)
Seventeen complexes, LW(CO)5, where L = amine, pyridine, or phosphine, have been prepared and examined in the C-O stretching region of their infrared spectra. The C-O stretching frequencies and force constants in the amine, pyridine, and phosphine series decrease as the basicity of L increases, and the magnitude of this decrease is virtually the same for all three groups of ligands. The results suggest that W-L π bonding, even for the phosphines, need not be invoked to explain the C-O stretching frequency shifts in these metal carbonyl complexes.
Thermodynamics and equilibrium solubility of carbon dioxide in diglycolamine/morpholine/water
Al-Juaied, Mohammed,Rochelle, Gary T.
, p. 708 - 717 (2006)
Carbon dioxide solubility was studied in 3.5 m (23.5 wt %) morpholine (MOR), 17.7 m (65 wt %) 2-aminoethoxyethanol (diglycolamine or DGA), and 3.6 m MOR + 14.7 m DCA (11 wt % MOR + 53 wt % DGA). CO2 solubility was determined by dynamic measurements with a wetted wall contactor. Carbamate and bicarbonate concentrations were determined by 13C NMR in solutions loaded with 13CO2. The data are represented by the electrolyte NRTL model. At a given CO2 loading (mol/mol amine), the CO2 vapor pressure over 3.5 m MOR is 10 to 1000 times greater than 17.7 m DGA. In 3.6 m MOR + 14.7 m DGA, the CO2 vapor pressure is 5 to 7 times greater than in 17.7 m DGA at high CO2 loading, but the same below 0.2 loading. MOR carbamate is less stable than DGA carbamate by a factor of 7 to 10 from (300 to 333) K. The model predicts that MOR vapor pressure is 100 times greater than DGA over 3.6 m MOR + 14.7 m DGA from (313 to 333) K. The heat of CO2 absorption in the blend is equivalent to 17.7 m DGA up to 0.35 loading but is 40 % lower at 0.5 loading. The working capacity of the blend is 17 % less than 17.7 m DGA.
The pyridoxamine action on Amadori compounds: A reexamination of its scavenging capacity and chelating effect
Adrover, Miquel,Vilanova, Bartolome,Frau, Juan,Munoz, Francisco,Donoso, Josefa
, p. 5557 - 5569 (2008)
Amadori compounds act as precursors in the formation of advanced glycation end products (AGEs) by non-enzymatic protein glycation, which are involved in ensuing protein damage. Pyridoxamine is a potent drug against protein glycation, and can act on several pathways in the glycation process. Nevertheless, the pyridoxamine inhibition action on Amadori compounds oxidation is still unclear. In this work, we have studied the Schiff base formation between pyridoxamine and various Amadori models at pH 7.4 at 37 °C in the presence of NaCNBH3. We detected an adduct formation, which suggests that pyridoxamine reacts with the carbonyl group in Amadori compounds. The significance of this mechanism is tested by comparison of the obtained kinetics rate constants with that obtained for 4-(aminomethyl)-pyridine, a structural analogue of pyridoxamine without post-Amadori action. We also study the chelating effect of pyridoxamine on metal ions. We have determined the complexation equilibrium constants between pyridoxamine, N-(1-deoxy-d-fructos-1-yl)-l-tryptophan, aminoguanidine, and ascorbic acid in the presence of Zn2+. The results show that the strong stability of pyridoxamine complexes is the key in its post-Amadori inhibition action. On the other hand results explain the lack of inhibition of aminoguanidine (a glycation inhibitor) in the post-Amadori reactions.
