- Using dialkyl amide: Via forming hydrophobic deep eutectic solvents to separate citric acid from fermentation broth
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Nowadays, developing appropriate technology is one of the biggest challenges for society to reduce environmental impact. In this research, to avoid the traditional calcium salt method which produces a large amount of waste gypsum residue, a new way of separating citric acid from fermentation broth was developed by forming hydrophobic deep eutectic solvents (DESs), in which amide and citric acid were used as the hydrogen bond acceptor and donor respectively when amide was in contact with the fermentation broth containing citric acid. Among these amides, C10H21NO was found to be an efficient hydrogen bond acceptor forming hydrophobic DESs with the citric acid based on the molecular size and shape and has the largest hydrophobic equilibrium constant of 3.14. The hydrophobic DES formation mechanism was studied by analyzing the chemical bonds using FT-IR and quantum chemical (QC) calculations. C10H21NO was regenerated by elevating the temperature of the hydrophobic DESs. The regenerated C10H21NO exhibited good recycling properties with no obvious reduction of the ability to form hydrophobic DESs. This effective way of obtaining high-quality citric acids provides new ideas for the separation of other carboxylic acids.
- Liu, Lijuan,Wei, Qifeng,Zhou, Yong,Ren, Xiulian
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- Spectrophotometric Analysis of Ternary Uranyl Systems to Replace Tri-N-butyl Phosphate (TBP) in Used Fuel Reprocessing
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In this report, the interaction of monoamide/diamide and monoamide/diglycolamide mixtures with UO22+ are investigated in pH = 1 methanolic nitric acid media. These monoamides include N,N-dimethylacetamide (DMAA), N,N-diethylacetamide (DEAA), N,N-dibutylacetamide (DBAA) and N,N-dibutylbutanamide (DBBA). N,N,N′N′-tetraethylmalonamide (TEMA) and N,N,N′,N′-tetraethyldiglycolamide (TEDGA), which were chosen as model diamides and diglycolamides, respectively. Complex stability constants for each ligand were modelled using the Stability Quotients Using Absorbance Data program using UV–visible data. Complex stoichiometry of ligand mixtures was determined using Job plots and UV–Vis spectrometry. Monoamides were confirmed to produce only disolvate complexes with UO22+ in solution. The log10(K) values for monoamides were found to be independent of amine-side chain length, but were slightly dependent on the carbonyl-side chain length. TEDGA was found to produce multiple uranyl complexes in solution. Job plot data indicated that the uranyl cation strongly prefers to bond either only with the monoamide or diamide in ternary monoamide–diamide–UO2 systems. Monoamide–diglycolamide–UO2 systems were more complicated, with Job plot data indicating the potential for multiple ternary species being present is dependent on the monoamide structure.
- Canner, Adam J.,Harwood, Laurence M.,Cowell, Joseph,Babra, Jasraj S.,Brown, Solomon F.,Ogden, Mark D.
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- Iron-catalyzed Cα-H oxidation of tertiary, aliphatic amines to amides under mild conditions
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De novo syntheses of amides often generate stoichiometric amounts of waste. Thus, recent progress in the field has focused on precious metal catalyzed, oxidative protocols to generate such functionalities. However, simple tertiary alkyl amines cannot be used as starting materials in these protocols. The research described herein enables the oxidative synthesis of amides from simple, noncyclic tertiary alkyl amines under synthetically useful, mild conditions through a biologically inspired approach: Fe-catalyzed Cα-H functionalization. Mechanistic investigations provide insight into reaction intermediates and allow the development of a mild Cα-H cyanation method using the same catalyst system. The protocol was further applied to oxidize the drug Lidocaine, demonstrating the potential utility of the developed chemistry for metabolite synthesis. Let′s iron it out! The title reaction enables the oxidative synthesis of amides directly from tertiary, noncyclic alkyl amines under synthetically useful, mild conditions through a biologically inspired approach employing oxidative iron catalysis. Mechanistic studies suggest that hemiaminals are likely intermediates in this reaction and that the catalytic system can be employed for other Cα-H oxidations of amines.
- Legacy, Christopher J.,Wang, Anqi,O'Day, Brian J.,Emmert, Marion H.
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supporting information
p. 14907 - 14910
(2016/02/05)
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- Catalyst-free amidation of aldehyde with amine under mild conditions
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A highly efficient, catalyst-free and one-pot procedure for the direct synthesis of amides from aldehydes and amines under mild conditions has been developed. Both aliphatic and aromatic aldehydes with primary or secondary amines are successfully converted to the corresponding amides, and it is observed that reactions can proceed in either aqueous or organic media.
- Yang, Hongyin,Hu, Wenjian,Deng, Shengjue,Wu, Tiantian,Cen, Haiman,Chen, Yiping,Zhang, Dela,Wang, Bo
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supporting information
p. 5912 - 5915
(2015/08/11)
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- Iron-catalyzed oxidative amidation of tertiary amines with aldehydes
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Unconventional couple: A new oxidative coupling protocol for amide bond formation has been developed (see scheme). The method provides an efficient and practical route for the synthesis of tertiary amides from readily available tertiary amines and aldehydes in the presence of a simple FeCl2 catalyst. Mechanistic studies indicated that a peroxide and an iminium ion act as the reactive intermediates in this oxidative amidation.
- Li, Yuanming,Jia, Fan,Li, Zhiping
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supporting information
p. 82 - 86
(2013/03/13)
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- Diesters of carbonic acid endowed with antiviral and anti-inflammatory activity
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Diesters of carbonic acid disubstituted with primary, secondary or tertiary amine groups, pharmaceutically acceptable salts thereof, and their use as antiviral and inti-inflammatory agents.
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- A facile one-pot transformation of carboxylic acids to amides
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Carboxylic acids, converted in situ into carboxylic-(p-nitrobenzene)sulfonic anhydrides using p-nitrobenzenesulfonyl chloride, Et3N, and DMAP in CH3CN, react with primary or secondary amines, to give amides in high yields.
- Lee,Cho,Lee,Cho
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p. 2877 - 2881
(2007/10/02)
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- Formation and Characterisation of Enamine Complexes of Palladium(II) Chloride. Crystal Structure Analysis of Di-μ-chlorodichlorobisdipalladium(II).
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Reaction of certain tertiary amines with PdCl2*2RCN (R=Ph or Me) gives palladium(II) enamine complexes in which the palladium is coordinated in a η1-fashion to the β carbon atom.Complexes of this type have also been prepared (i) by direct reaction of enamines with PdCl2*2RCN, (ii) from enol ether complexes of Pd(II) by vinyl exchange, and (iii) from a β-diethylaminoalkyl-palladium(II) species.
- McCrindle, Robert,Ferguson, George,Arsenault, Gilles J.,McAlees, Alan J.,Stephenson, Donald K.
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p. 3301 - 3344
(2007/10/02)
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