109-73-9Relevant articles and documents
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Vaughan et al.
, p. 819,821 (1955)
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Kinetics of Amine Addition to Benzylidenemalonodialdehyde in 50percent Me2SO-50percent water
Bernasconi, Claude F.,Stronach, Michael W.
, p. 1993 - 2001 (1991)
The kinetics of the reaction of benzylidenemalonodialdehyde with piperidine, morpholine, n-butylamine, 2-methoxyethylamine, glycinamide, glycine ethyl ester, cyanomethylamine, and semicarbazide have been determined in 50percent aqueous Me2SO at 20 deg C.The reaction leads to a zwitterionic adduct, PhCH(RR'NH(1+))C(CHO)2(1-) (TA(+/-)), that is in fast acid-base equilibrium with the anionic adduct, PhCH(RR'N)C(CHO)2(1-) (TA(1-)).With strongly basic amines at high pH there is also attack of the amine on one of the carbonyl groups, which acts as a rapid preequilibrium.Rate constants for the formation of TA(+/-) (k1) and its reverse (k-1), as well as equilibrium constants (K1 = k1/k-1) and the pKa of TA(+/-) were determined for all the amines.Intrinsic rate constants (k0 = k1 = k-1 when K1 = 1) were calculated.The intrinsic rate constants are lower than those for amine addition to benzylidene Meldrum's acid.This is consistent with the greater role played by resonance in stabilizing TA(+/-) derived from benzylidenemalonodialdehyde.However, k0 for piperidine/morpholine addition to benzylidenemalonodialdehyde is much higher than for the reaction of benzylideneacetylacetone with the same amines, indicating that the rate-depressing effect of intramolecular hydrogen bonding in TA(+/-) derived from benzylidenemalonodialdehyde is much smaller than that in TA(+/-) derived from benzylideneacetylacetone.Even though semicarbazide is an α-effect nucleophile, no enhancement of k1 was observed, but K1, estimated on the basis of a structure-reactivity relationship, is larger than expected based on the pKa of the amine.This result is attributed to a low νnucn value.
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Davis,Yelland
, p. 1998 (1937)
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Kinetic and equilibrium studies of σ-adduct formation and nucleophilic substitution in the reactions of trinitro-activated benzenes with aliphatic amines in acetonitrile
Crampton, Michael R.,Lord, Simon D.
, p. 369 - 376 (1997)
Rate and equilibrium constants are reported for reactions in acetonitrile of butylamine, pyrrolidine and piperidine with 1,3,5-trinitrobenzene, 1, and with ethyl 2,4,6-trinitrophenyl ether, 4a, and phenyl 2,4,6-trinitrophenyl ether, 4b. Rapid nucleophilic attack at unsubstituted ring-positions may yield anionic σ-adducts via zwitterionic intermediates, while slower attack at the 1-position of 4a and 4b may lead to substitution to give 2,4,6-trinitroaniline derivatives. Base catalysis in the substitution reaction reflects rate-limiting proton transfer which may be from the zwitterionic intermediates to amine in the case of 4b, or from a substituted ammonium ion to the ethoxy leaving group in the case of 4a. Comparisons with values in DMSO indicate that values of overall equilibrium constants for adduct formation are ca. 104 lower in acetonitrile, while rate constants for proton transfer are ca. 104 higher. These differences may reflect strong hydrogen-bonding between DMSO and -NH+ protons in ammonium ions and in zwitterions. In acetonitrile homoconjugation of substituted ammonium ions with free amine is an important factor.
Charged states of proteins. Reactions of doubly protonated alkyldiamines with NH3: Solvation or deprotonation. Extension of two proton cases to multiply protonated globular proteins observed in the gas phase
Peschke, Michael,Blades, Arthur,Kebarle, Paul
, p. 11519 - 11530 (2002)
The apparent gas-phase basicities (GBapp'S) of basic sites in multiply protonated molecules, such as proteins, can be approximately predicted. An approach used by Williams and co-workers was to develop an equation for a diprotonated system, NH
Electron Spin Resonance Monitoring of Ligand Ejection Reactions Following Solid-State Reduction of Cobalt Globin and Cobalt Protoporphyrin Complexes
Dickinson, L. Charles,Symons, M. C. R.
, p. 917 - 921 (1982)
Cobaltihemoglobin, isolated α and β chains, and cobaltimyoglobin in aqueous solution at neutral pH were irradiated at 77 K with 3 Mrd of 60Co γ-rays.These diamagnetic Co(III) species are converted to paramagnetic Co(II) species in high yield.The EPR spectra are identical with those of authentic six-coordinate cobalt(II) porphyrins.Upon partial annealing of the species, the EPR spectrum transforms irreversibly to that of a five-coordinate species, indicating that at 77 K these cobaltiglobins are cobaltichromes in analogy to the hemichromes of the native iron species.Differences are seen among all of the six-coordinate, reduced protein ligated species.This ejection of the sixth ligand with thermal annealing after addition of one electron to the dz2 orbital of the cobalt porphyrin also occurs in aqueous glasses of cobalt protoporphyrin IX in pyridine, n-butylamine, or quinuclidine.The five-coordinate species in aqueous media are stable with annealing to room temperature.
Selective Transformations of Triglycerides into Fatty Amines, Amides, and Nitriles by using Heterogeneous Catalysis
Jamil, Md. A. R.,Siddiki, S. M. A. Hakim,Touchy, Abeda Sultana,Rashed, Md. Nurnobi,Poly, Sharmin Sultana,Jing, Yuan,Ting, Kah Wei,Toyao, Takashi,Maeno, Zen,Shimizu, Ken-ichi
, p. 3115 - 3125 (2019)
The use of triglycerides as an important class of biomass is an effective strategy to realize a more sustainable society. Herein, three heterogeneous catalytic methods are reported for the selective one-pot transformation of triglycerides into value-added chemicals: i) the reductive amination of triglycerides into fatty amines with aqueous NH3 under H2 promoted by ZrO2-supported Pt clusters; ii) the amidation of triglycerides under gaseous NH3 catalyzed by high-silica H-beta (Hβ) zeolite at 180 °C; iii) the Hβ-promoted synthesis of nitriles from triglycerides and gaseous NH3 at 220 °C. These methods are widely applicable to the transformation of various triglycerides (C4–C18 skeletons) into the corresponding amines, amides, and nitriles.
Amination of ω-Functionalized Aliphatic Primary Alcohols by a Biocatalytic Oxidation-Transamination Cascade
Pickl, Mathias,Fuchs, Michael,Glueck, Silvia M.,Faber, Kurt
, p. 3121 - 3124 (2015)
Amination of non-activated aliphatic fatty alcohols to the corresponding primary amines was achieved through a five-enzyme cascade reaction by coupling a long-chain alcohol oxidase from Aspergillus fumigatus (LCAO-Af) with a ω-transaminase from Chromobacterium violaceum (ω-TA-Cv). The alcohol was oxidized at the expense of molecular oxygen to yield the corresponding aldehyde, which was subsequently aminated by the PLP-dependent ω-TA to yield the final primary amine product. The overall cascade was optimized with respect to pH, O2 pressure, substrate concentration, decomposition of H2O2 (derived from alcohol oxidation), NADH regeneration, and biocatalyst ratio. The substrate scope of this concept was investigated under optimized conditions by using terminally functionalized C4-C11 fatty primary alcohols bearing halogen, alkyne, amino, hydroxy, thiol, and nitrile groups.
Reilly, J.,Hickinbottom, W. J.
, p. 974 - 985 (1918)
N,N-Chelate nickel(II) complexes bearing Schiff base ligands as efficient hydrogenation catalysts for amine synthesis
Xu, Mengyin,Wang, Yang,Zhou, Yifeng,Yao, Zi-Jian
, (2021/12/09)
Five N, N-chelate nickel (II) complexes bearing N-(2-pyridinylmethylene)-benzylamine ligands with different substituent groups were synthesized in good yields. The nickel complexes exhibited prominent catalytic efficiency toward amine synthesis from nitro compounds by using NaBH4 or H2 as hydrogen source through two catalytic systems. Various amines with different substituents were obtained in moderate to excellent yields. All substrates with electron-donating and electron-withdrawing properties were tolerated in the two reduction systems. Given the efficient catalytic activity, broad substance scope, and mild reduction conditions, the nickel catalysts have potential applications in industrial production.
Synthesis, Structure, and Catalytic Hydrogenation Activity of [NO]-Chelate Half-Sandwich Iridium Complexes with Schiff Base Ligands
Lv, Wen-Rui,Li, Rong-Jian,Liu, Zhen-Jiang,Jin, Yan,Yao, Zi-Jian
, p. 8181 - 8188 (2021/05/26)
A series of N,O-coordinate iridium(III) complexes with a half-sandwich motif bearing Schiff base ligands for catalytic hydrogenation of nitro and carbonyl substrates have been synthesized. All iridium complexes showed efficient catalytic activity for the hydrogenation of ketones, aldehydes, and nitro-containing compounds using clean H2 as reducing reagent. The iridium catalyst displayed the highest TON values of 960 and 950 in the hydrogenation of carbonyl and nitro substrates, respectively. Various types of substrates with different substituted groups afforded corresponding products in excellent yields. All N,O-coordinate iridium(III) complexes 1-4 were well characterized by IR, NMR, HRMS, and elemental analysis. The molecular structure of complex 1 was further characterized by single-crystal X-ray determination.
