12624-24-7Relevant academic research and scientific papers
Synthesis of glycidamide from acrylonitrile using basic hydrotalcite catalyst in the presence of aqueous hydrogen peroxide and unsaturated amide
Fujiwara, Shinpei,Nishimura, Shun,Ebitani, Kohki
, p. 1716 - 1718 (2014)
Glycidamide (GA) can be synthesized from acrylonitrile (AN) by using hydrotalcite as a solid base catalyst and 25% aqueous H2O2 as an oxidant, in the presence of acrylam ide (AA) as a cocatalyst in methanol solvent at 313K for 18 h. The GA yield and H2O2 utilization efficiency reached 74% and 60%, respectively. The hydrotalcite catalyst could be easily separated from the reaction mixture and reused at least once.
Toward a kinetic model for acrylamide formation in a glucose-asparagine reaction system
Knol, Jeroen J.,Van Loon, Wil A. M.,Linssen, Jozef P. H.,Ruck, Anne-Laure,Van Boekel, Martinus A. J. S.,Voragen, Alphons G. J.
, p. 6133 - 6139 (2005)
A kinetic model for the formation of acrylamide in a glucose-asparagine reaction system is proposed. Equimolar solutions (0.2 M) of glucose and asparagine were heated at different temperatures (120-200°C) at pH 6.8. Besides the reactants, acrylamide, fructose, and melanoidins were quantified after predetermined heating times (0-45 min). Multiresponse modeling by use of nonlinear regression with the determinant criterion was used to estimate model parameters. The proposed model resulted in a reasonable estimation for the formation of acrylamide in an aqueous model system, although the behavior of glucose, fructose, and asparagine was slightly underestimated. The formation of acrylamide reached its maximum when the concentration of sugars was reduced to about 0. This supported previous research, showing that a carbonyl source is needed for the formation of acrylamide from asparagine. Furthermore, it is observed that acrylamide is an intermediate of the Maillard reaction rather than an end product, which implies that it is also subject to a degradation reaction.
Nanoscopic Naked Cu/Pd Powder as Air-Resistant Active Catalyst for Selective Hydration of Acrylonitrile to Acrylamide
Wang, Yuan,Liu, Hanfan,Toshima, Naoki
, p. 19533 - 19537 (1996)
Nanoscopic naked Cu/Pd alloy powders, particle size in 1-5 nm, were prepared by a cold alloying process.The formation of nanoscopic bimetallic hydroxide colloids as precursors of the nanoscopic alloy powders was studied by means of TEM, XRD, and a titration method.These bimetallic alloy powders have provided the first example of Cu-based catalysts with high activity, selectivity, and stability against air for the selective hydration of acrylonitrile to acrylamide.
Analyzing the function of the insert region found between the α and β-subunits in the eukaryotic nitrile hydratase from Monosiga brevicollis
Yang, Xinhang,Bennett, Brian,Holz, Richard C.
, p. 1 - 7 (2018)
The functional roles of the (His)17 region and an insert region in the eukaryotic nitrile hydratase (NHase, EC 4.2.1.84) from Monosiga brevicollis (MbNHase), were examined. Two deletion mutants, MbNHaseΔ238?257 and MbNHaseΔ219?272, were prepared in which the (His)17 sequence and the entire insert region were removed. Each of these MbNHase enzymes provided an α2β2 heterotetramer, identical to that observed for prokaryotic NHases and contains their full complement of cobalt ions. Deletion of the (His)17 motif provides an MbNHase enzyme that is ～55% as active as the WT enzyme when expressed in the absence of the Co-type activator (ε) protein from Pseudonocardia thermophila JCM 3095 (PtNHaseact) but ～28% more active when expressed in the presence of PtNHaseact. MbNHaseΔ219?272 exhibits ～55% and ～89% of WT activity, respectively, when expressed in the absence or presence of PtNHaseact. Proteolytic cleavage of MbNHase provides an α2β2 heterotetramer that is modestly more active compared to WT MbNHase (kcat = 163 ± 4 vs 131 ± 3 s?1). Combination of these data establish that neither the (His)17 nor the insert region are required for metallocentre assembly and maturation, suggesting that Co-type eukaryotic NHases utilize a different mechanism for metal ion incorporation and post-translational activation compared to prokaryotic NHases.
DJ-1 family Maillard deglycases prevent acrylamide formation
Richarme, Gilbert,Marguet, Evelyne,Forterre, Patrick,Ishino, Sonoko,Ishino, Yoshizumi
, p. 1111 - 1116 (2016)
The presence of acrylamide in food is a worldwide concern because it is carcinogenic, reprotoxic and neurotoxic. Acrylamide is generated in the Maillard reaction via condensation of reducing sugars and glyoxals arising from their decomposition, with asparagine, the amino acid forming the backbone of the acrylamide molecule. We reported recently the discovery of the Maillard deglycases (DJ-1/Park7 and its prokaryotic homologs) which degrade Maillard adducts formed between glyoxals and lysine or arginine amino groups, and prevent glycation damage in proteins. Here, we show that these deglycases prevent acrylamide formation, likely by degrading asparagine/glyoxal Maillard adducts. We also report the discovery of a deglycase from the hyperthermophilic archaea Pyrococcus furiosus, which prevents acrylamide formation at 100?°C. Thus, Maillard deglycases constitute a unique enzymatic method to prevent acrylamide formation in food without depleting the components (asparagine and sugars) responsible for its formation.
Biomimetic-functionalized, tannic acid-templated mesoporous silica as a new support for immobilization of nhase
Gao, Jun-kai,Zhang, Zi-jun,Jiang, Yan-jun,Chen, Yan,Gao, Shu-feng
, (2017)
Tannic acid-templated mesoporous silica (TAMS) was synthesized using a simple nonsurfactant template method and dopamine-functionalized TAMS (Dop-TAMS), which was prepared via a biomimetic coating, was developed as a new support for immobilization of NHase (NHase@Dop-TAMS). The Dop-TAMS was thoroughly characterized by the transmission electron microscopy (TEM), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), and Fourier transform infrared (FT-IR) and the results showed that the Dop-TAMS possessed sufficiently large pore size and volume for the accommodation of NHase. Studying the thermal stability, storage, shaking stability, and pH stability of the free and immobilized NHase indicated that the catalytic properties of NHase@Dop-TAMS were significantly enhanced. Moreover, the NHase@Dop-TAMS exhibited good reusability. All the results demonstrated that Dop-TAMS could be used as an excellent matrix for the immobilization of NHase.
Water soluble diphosphine ligands based on 1,3,5-triaza-7-phosphaadamantane (PTA-PR2): Synthesis, coordination chemistry, and ruthenium catalyzed nitrile hydration
Sears, Jeremiah M.,Lee, Wei-Chih,Frost, Brian J.
, p. 248 - 257 (2015)
Two chiral chelating 1,3,5-triaza-7-phosphaadamantane (PTA) derivatives were synthesized, in racemic form, by addition of ClPiPr2 or ClP(NiPr)2(CH2)2 to lithiated PTA. PTA-PiPr2 (1) and PTA-P(NiPr)2(CH2)2 (2) were isolated in good yield, 73% and 56% respectively, and fully characterized by multinuclear NMR spectroscopy, mass spectrometry, and X-ray crystallography. PTA-PiPr2 is highly air sensitive, but stable and somewhat soluble in degassed water. PTA-P(NiPr)2(CH2)2 (2) is air-stable, but decomposes in water over the course of hours. Two tungsten tetracarbonyl complexes were prepared by addition of the PTA-PR2 to [W(CO)4(pip)2] and characterized by NMR and IR spectroscopies and X-ray crystallography in the case of [W(CO)4(PTA-PiPr2)]. Based on IR spectroscopy PTA-PiPr2 (1) is more electron donating than PTA-P(NiPr)2(CH2)2 (2) or the previously published PTA-PPh2. Products isolated from the reaction of [(η6-toluene)RuCl2]2 with two equivalents of 1 were found to contain monodentate (κ1), bidentate (κ2), and possibly bridging coordination modes of PTA-PiPr2. These ruthenium complexes were explored as catalysts for aqueous phase nitrile hydration. Of the ruthenium complexes explored [(η6-toluene)RuCl2(κ1-PTA-PiPr2)] (7) was the most active towards nitrile hydration. In the presence of air at 100°C 7 converted various nitriles to the respective amides with 43-99% conversions in 7 h.
Production of acrylamide using alginate-immobilized E. coli expressing Comamonas testosteroni 5-MGAM-4D nitrile hydratase
Mersinger, Lawrence J.,Hann, Eugenia C.,Cooling, Frederick B.,Gavagan, John E.,Ben-Bassat, Arie,Wu, Shijun,Petrillo, Kelly L.,Payne, Mark S.,DiCosimo, Robert
, p. 1125 - 1131 (2005)
A thermally-stable nitrile hydratase produced by Comamonas testosteroni 5-MGAM-4D has been expressed in Escherichia coli, and the alginate-immobilized transformant evaluated as catalyst for the conversion of acrylonitrile to acrylamide. In batch reactions with catalyst recycle, the catalyst productivity decreased with increasing acrylonitrile concentration or reaction temperature, but was relatively insensitive to acrylamide concentration. A total of 206 consecutive batch reactions with catalyst recycle were run at 5°C and produced 1035 g acrylamide/g dry cell weight and 95 g acrylamide/L; the initial and final volumetric productivities of this series of recycle reactions were 197 and 96 g acrylamide/L/h, respectively. A packed column reactor yielded lower catalyst productivity than consecutive batch recycle reactions, presumably due to contact of the fixed-bed catalyst with a constant high concentration of acrylonitrile.
Aqueous and biphasic nitrile hydration catalyzed by a recyclable Ru(ii) complex under atmospheric conditions
Lee, Wei-Chih,Frost, Brian J.
, p. 62 - 66 (2012)
[RuCl2(PTA)4] (PTA = 1,3,5-triaza-7- phosphaadamantane) was found to be a highly active catalyst for aqueous phase nitrile hydration at 100 °C in air. Near quantitative conversion of aromatic, alkyl, and vinyl nitriles to their corresponding amides was observed. The reaction tolerated ether, hydroxyl, nitro, bromo, formyl, pyridyl, benzyl, alkyl, and olefinic functional groups. Some amides were isolated by simple decantation from the aqueous phase catalyst. Catalyst loading down to 0.001 mol% was examined with turnover numbers as high as 22000 observed. The catalyst was stable for weeks in solution and could be reused more than five times without significant loss of activity.
Liquid-Phase Hydration of Acrylonitrile on Skeletal Copper Catalysts Prepared from Cu-Ti and Cu-Zr Amorphous Alloys
Funabiki, Takuzo,Yamashita, Hiromi,Yase, Makoto,Omatsu, Toshihiro,Yoshida, Satohiro
, p. 2133 - 2136 (1993)
Liquid-phase hydration of acrylonitrile has been carried out on the skeletal copper catalysts which were prepared by treating pulverized amorphous Cu-Ti and Cu-Zr alloys with an HF solution.The catalysts from amorphous alloys were more effective to produce acrylamide selectively than those from crystalline alloys.This high activity was brought about by the highly homogeneous structure of the amorphous alloys.
