4466-24-4Relevant academic research and scientific papers
Photophysical Properties of Saturated Amines in Slightly Polar Media. Saturated Ethers
Halpern, Arthur M.
, p. 1682 - 1685 (1981)
The fluorescence properties of a prototype saturated amine, N,N-diethylmethylamine (DEMA), were examined in diethyl ether and in tetrahydrofuran (THF).In going from a nonpolar medium (n-hexane) to more polar media (diethyl ether and THF), the fluorescence of DEMA undergoes a substantial red shift (292-308-340 nm), along with a diminution in quantum efficiency and an increase in lifetime.The shift in the fluorescence spectrum occurs continuously as the amount of THF in THF/n-hexane mixed solvents in increased.These observations are discussed within the framework of universal and specific interactions.Consideration is also taken of the change in geometry of DEMA in the ground and excited states, and some properties of a "rigid" amine, 1-azabicyclooctane, are compared and discussed.The question of specific complexation of the amine excited state with the solvent molecules is raised (amine / ether exciplex), and it is concluded on the basis of the properties of aminoether model compounds that a 1:1 exciplex cannot account for the observed photophysical properties.It seems possible that the original view of Muto, Nakato, and Tsubomura that the ether solvent media stabilize the Rydberg or Rydberg-like excited state of the amines may account satisfactorily for the observations.
Characterization of initial reaction intermediates in heated model systems of glucose, glutathione, and aliphatic aldehydes
Wang, Tianze,Zhen, Dawei,Tan, Jia,Xie, Jianchun,Cheng, Jie,Zhao, Jian
, (2019/09/12)
To understand the effect of lipid degradation on Maillard formation of meaty flavors, initial reaction intermediates in model systems of glucose–glutathione with hexanal, (E)-2-heptenal, or (E,E)-2,4-decadienal were identified by HPLC–MS and by NMR. Besides Amadori compounds, hemiacetals and thiazolidines via addition of sulfhydryl to carbonyl or to the conjugated olefinic bond were found. Concentrations of all intermediates increased with reaction time while degradation of the intermediates with a glutathione moiety helped formation of thiazolidines with cysteinylglycine. The unsaturated aldehydes (E)-2-heptenal and (E,E)-2,4-decadienal exhibited high reactivity against glucose for glutathione, yielding higher levels of intermediate compounds than from glucose. Heating prepared intermediates reversibly released the original aldehydes, which caused various compounds formed by retro-aldol, oxidation, etc. to react with H2S and NH3. Among them, formation pathways including 3-nonen-2-one, 2-hexanoylfuran, and six dialkylthiophenes (e.g., 2-ethyl-5-(1-methylbutyl)thiophene) were proposed for the first time.
Nickel complex catalyzed efficient activation of sp3and sp 2c-h bonds for alkylation and arylation of oxygen containing heterocyclic molecules
Gartia, Yashraj,Ramidi, Punnamchandar,Jones, Darin E.,Pulla, Sharon,Ghosh, Anindya
, p. 507 - 515 (2014/06/24)
A nickel(II) complex (1) of N,N'-bis(2,6-diisopropylphenyl)-2,6- pyridinedicarboxamido (L) ligand was examined for catalytic coupling of Grignard reagents with the C-H bond of oxygen containing heterocyclic compounds such as tetrahydrofuran and furan. The nickel( II) complex showed excellent activity in catalyzing C-H activation and further coupling with various Grignard reagents. The effective activation of the C-H bond proceeded under ambient reaction conditions with a short reaction time (1-2 h). The catalyst (1) displays high turnover frequency of 4,130 h-1with catalyst loading as low as 0.01 mol%. This catalytic route could prove to be an efficient mode of activation of sp3and sp2C-H bonds in various heterocycles for the preparation of synthetically and pharmaceutically relevant molecules. Springer Science+Business Media New York 2013.
Activation of sp3 and sp2 C-H bonds of oxygen containing heterocyclic molecules for alkylation and arylation reactions catalyzed by an iron complex
Gartia, Yashraj,Ramidi, Punnamchandar,Cheerla, Sreevishnu,Felton, Charlette M.,Jones, Darin E.,Das, Bhaskar C.,Ghosh, Anindya
, p. 253 - 259 (2014/07/07)
Activation of both sp3 and sp2 CH bonds is reported using an efficient iron(III) complex (1) of a ligand (N2,N6-bis(2,6- diisopropylphenyl)pyridine-2,6-dicarboxamide: L). The iron(III) complex showed catalytic activity of CC coupling reaction of oxygen containing heterocycles, e.g. tetrahydrofuran (THF), with various alkyl, allyl and aryl Grignard reagents under ambient reaction conditions. Complex 1 demonstrated excellent activity and reactions were completed within 30 min to 1 h. A high turnover frequency (TOF) of 1700 h-1 using a low catalyst loading of 0.02 mol% was obtained for the reaction. Interestingly, the catalyst was selective in activation of the CH bond adjacent to the oxygen in various oxygen containing heterocyclic molecules to yield 2-substitituted products.
Catalytic conversion of furan to gasoline-range aliphatic hydrocarbons via ring opening and decarbonylation reactions catalyzed by Pt/γ-Al 2O3
Runnebaum, Ron C.,Nimmanwudipong, Tarit,Doan, Jonathan,Block, David E.,Gates, Bruce C.
experimental part, p. 664 - 666 (2012/10/07)
Conversion of furan in the presence of H2 catalyzed by Pt/γ-Al2O3 at 573 K and 1.4 bar leads to the formation of alkanes and alkenes, some in the gasolinerange, including C7 hydrocarbons, butenes, propene, and propane.
Synthesis of 2-substituted furans by iron- and palladium-catalyzed coupling reactions
Haner, Jamie,Jack, Kelsey,Nagireddy, Jaipal,Raheem, Mohammed Abdul,Durham, Robin,Tam, William
experimental part, p. 731 - 738 (2011/04/24)
The synthesis of 2-substituted furans via palladium- and iron-catalyzed coupling utilizing 2-bromofuran is described. Whereas palladium-catalyzed Suzuki coupling effectively provided the corresponding aryl furans, little or no product was obtained by palladium-catalyzed coupling with various alkyl nucleophiles. Iron-catalyzed coupling proved effective for the synthesis of primary and secondary alkyl furans in modest yields and aryl furans in low yields. Georg Thieme Verlag Stuttgart New York.
Amino acid catalysis of 2-alkylfuran formation from lipid oxidation-derived α,β-unsaturated aldehydes
Adams, An,Bouckaert, Capucine,Van Lancker, Fien,De Meulenaer, Bruno,De Kimpe, Norbert
experimental part, p. 11058 - 11062 (2012/02/06)
The formation of 2-alkylfurans from the corresponding lipid-derived α,β-unsaturated aldehydes under dry-roasting conditions was investigated in detail. The addition of an amino acid to an α,β- unsaturated aldehyde drastically increased 2-alkylfuran formation. Peptides and proteins as well were able to catalyze 2-alkylfuran formation from the corresponding α,β-unsaturated aldehydes. Further investigation of 2-alkylfuran formation showed the need of oxidizing conditions and the involvement of radicals in the reaction. This way, the formation of 2-methylfuran from 2-pentenal, 2-ethylfuran from 2-hexenal, 2-propylfuran from 2-heptenal, 2-butylfuran from 2-octenal, 2-pentylfuran from 2-nonenal, and 2-hexylfuran from 2-decenal was shown. The impact of amino acids on 2-alkylfuran formation from lipid-derived α,β-unsaturated aldehydes represents an interesting example of the complex role of amino acids in the multitude of chemical reactions occurring during thermal processing of lipid-rich foods.
One-pot hydrogenation conditions for a sequential process to (+)-monomorine
Kim, Guncheol,Jung, Sung-do,Lee, Eun-ju,Kim, Nakjeong
, p. 5395 - 5398 (2007/10/03)
(+)-Monomorine has been synthesized under mild hydrogenation conditions initiating deprotection followed by intramolecular, sequential reductive amination reactions. The precursors could be prepared concisely using B-alkyl Suzuki cross coupling of a chiral homoallylamine and a vinyl iodide or an iodofuran derivative.
Preparation of furans by palladium-catalyzed reaction of acylchromates and propargylic tosylates
Nakamura, Masaki,Yamane, Motoki,Sakurai, Hidehiro,Narasaka, Koichi
, p. 333 - 345 (2007/10/03)
Substituted furans are prepared by the palladium-catalyzed reaction of propargylic tosylates with acylchromates. The reaction is initiated by the oxidative additiion of propagylic tosylates to palladium(O) complexes to give 1,2-propadienylpalladium(II) co
Addition of carbon nucleophiles to aldehyde tosylhydrazones of aromatic and heteroaromatic-compounds: Total synthesis of piperine and its analogs
Chandrasekhar,Venkat Reddy,Srinivasa Reddy,Ramarao
, p. 2667 - 2670 (2007/10/03)
Addition of carbon nucleophiles to aldehyde tosylhydrazones of aromatic and heteroaromatic compounds is reported. New observations have been made wherein alkylative reduction is observed in some cases whereas alkylative fragmentation is noticed in others. These findings are exploited in the synthesis of the useful alkaloid piperine and its analogs. (C) 2000 Elsevier Science Ltd.
