- Selective conversion of glycerol to lactic acid with iron pincer precatalysts
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A family of iron complexes of PNP pincer ligands are active catalysts for the conversion of glycerol to lactic acid with high activity and selectivity. These complexes also catalyse transfer hydrogenation reactions using glycerol as the hydrogen source.
- Sharninghausen, Liam S.,Mercado, Brandon Q.,Crabtree, Robert H.,Hazari, Nilay
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- Highly Efficient Iridium-Catalyzed Production of Hydrogen and Lactate from Glycerol: Rapid Hydrogen Evolution by Bimetallic Iridium Catalysts
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Mono- and bimetallic iridium complexes involving novel triscarbene ligands were synthesized and applied to the dehydrogenation of biomass-derived glycerol. This resulted in affording hydrogen and lactate with the excellent turnover number (TON; 3,240,000) and turnover frequency (TOF; 162,000 h–1). The triscarbene ligand in a single frame allowed the formation of bimetallic iridium complexes. This induced the cooperative effect of two iridium ions and rendered excellent TONs and TOFs in the production of hydrogen and lactate.
- Cheong, Yeon-Joo,Sung, Kihyuk,Kim, Jin-A,Kim, Yu Kwon,Jang, Hye-Young
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Read Online
- Cannabichromene and Δ9-Tetrahydrocannabinolic Acid Identified as Lactate Dehydrogenase-A Inhibitors by in Silico and in Vitro Screening
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Cannabis sativa contains >120 phytocannabinoids, but our understanding of these compounds is limited. Determining the molecular modes of action of the phytocannabinoids may assist in their therapeutic development. Ligand-based virtual screening was used to suggest novel protein targets for phytocannabinoids. The similarity ensemble approach, a virtual screening tool, was applied to target identification for the phytocannabinoids as a class and predicted a possible interaction with the lactate dehydrogenase (LDH) family of enzymes. In order to evaluate this in silico prediction, a panel of 18 phytocannabinoids was screened against two LDH isozymes (LDHA and LDHB) in vitro. Cannabichromene (CBC) and Δ9-tetrahydrocannabinolic acid (Δ9-THCA) inhibited LDHA via a noncompetitive mode of inhibition with respect to pyruvate, with Ki values of 8.5 and 6.5 μM, respectively. In silico modeling was then used to predict the binding site for CBC and Δ9-THCA. Both were proposed to bind within the nicotinamide pocket, overlapping the binding site of the cofactor NADH, which is consistent with the noncompetitive modes of inhibition. Stemming from our in silico screen, CBC and Δ9-THCA were identified as inhibitors of LDHA, a novel molecular target that may contribute to their therapeutic effects.
- Martin, Lewis J.,Cairns, Elizabeth A.,Heblinski, Marika,Fletcher, Charlotte,Krycer, James R.,Arnold, Jonathon C.,McGregor, Iain S.,Bowen, Michael T.,Anderson, Lyndsey L.
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p. 1469 - 1477
(2021/05/29)
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- Scope and limitations of reductive amination catalyzed by half-sandwich iridium complexes under mild reaction conditions
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The conversion of aldehydes and ketones to 1° amines could be promoted by half-sandwich iridium complexes using ammonium formate as both the nitrogen and hydride source. To optimize this method for green chemical synthesis, we tested various carbonyl substrates in common polar solvents at physiological temperature (37 °C) and ambient pressure. We found that in methanol, excellent selectivity for the amine over alcohol/amide products could be achieved for a broad assortment of carbonyl-containing compounds. In aqueous media, selective reduction of carbonyls to 1° amines was achieved in the absence of acids. Unfortunately, at Ir catalyst concentrations of 1 mM in water, reductive amination efficiency dropped significantly, which suggest that this catalytic methodology might be not suitable for aqueous applications where very low catalyst concentration is required (e.g., inside living cells).
- Nguyen, Dat P.,Sladek, Rudolph N.,Do, Loi H.
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supporting information
(2020/07/15)
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- Efficient and Bio-inspired Conversion of Cellulose to Formic Acid Catalyzed by Metalloporphyrins in Alkaline Solution
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A bio-inspired approach for efficient conversion of cellulose to formic acid (FA) was developed in an aqueous alkaline medium. Metalloporphyrins mimicking cytochrome P450 exhibit efficiently and selectively catalytic performance in catalytic conversion of cellulose. High yield of FA about 63.7% was obtained by using sulfonated iron(III) porphyrin as the catalyst and O2 as the oxidant. Iron(III)-peroxo species, TSPPFeIIIOO?, was involved to cleave the C-C bonds of gluconic acid to FA in this catalytic system. This approach used relatively high concentration of cellulose and ppm concentration of catalyst. This work may provide a bio-inspired route to efficient conversion of cellulose to FA.
- Liu, Qiang,Zhou, Doudou,Li, Zongxiang,Luo, Weiping,Guo, Cancheng
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supporting information
p. 1063 - 1068
(2017/07/24)
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- GLUCOSYLCERAMIDE SYNTHASE INHIBITORS FOR THE TREATMENT OF DISEASES
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Described herein are compounds of Formula I, methods of making such compounds, pharmaceutical compositions and medicaments containing such compounds, and methods of using such compounds to treat or prevent diseases or conditions associated with the enzyme glucosylceramide synthase (GCS).
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Paragraph 000602
(2015/04/15)
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- Platinum on carbonaceous supports for glycerol hydrogenolysis: Support effect
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Metal vapor synthesis (MVS) technique was applied to generate Pt-nanoparticles of different size (1.3 nm and 2.5 nm) deposited onto carbonaceous supports, mainly characterized by a different surface area. The supported catalysts were employed in the glycerol hydrogenolysis reaction carried out under basic reaction conditions at 433 and 453 K to obtain 1,2-propanediol as the main liquid product. Comparison of the composition of the liquid- and gas-phase products obtained by the different catalysts showed a clear dependence of aqueous-phase reforming, water-gas shift reaction activity as well as 1,2-propanediol chemoselectivity on the degree of Pt-sintering occurring on different carbon supports. High-resolution transmission electron microscopic and X-ray powder diffraction studies carried out on as-synthesized and recovered heterogeneous catalysts provided clear evidences that a high surface area carbon support, such as Ketjen Black EC-600JD, notably retards nanoparticle aggregation.
- Oberhauser, Werner,Evangelisti, Claudio,Jumde, Ravindra P.,Psaro, Rinaldo,Vizza, Francesco,Bevilacqua, Manuela,Filippi, Jonathan,Machado, Bruno F.,Serp, Philippe
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p. 111 - 117
(2015/09/28)
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- The selective oxidation of 1,2-propanediol to lactic acid using mild conditions and gold-based nanoparticulate catalysts
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The use of bio-renewable resources for the generation of materials and chemicals continues to attract significant research attention. It is well established that glycerol is an excellent starting material for the production of 1,2-propanediol by dehydration/hydrogenation and that this can subsequently be oxidised to lactic acid, which has the potential to be used as a major chemical in the production of biodegradable polymers. Previous studies using gold catalysts for the oxidation of 1,2-propanediol have used elevated temperatures and pressures. We now show that the oxidation of 1,2-propanediol to form lactic acid can be carried out selectively under mild reaction conditions with gold-platinum catalysts prepared using a sol-immobilisation method, with activated carbon as the support. Carrying out the reaction at ambient temperature with air significantly improves the reaction in terms of its environmental impact and its industrial attractiveness, as lactic acid can be obtained with high selectivity.
- Ryabenkova, Yulia,He, Qian,Miedziak, Peter J.,Dummer, Nicholas F.,Taylor, Stuart H.,Carley, Albert F.,Morgan, David J.,Dimitratos, Nikolaos,Willock, David J.,Bethell, Donald,Knight, David W.,Chadwick, David,Kiely, Christopher J.,Hutchings, Graham J.
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p. 139 - 145
(2013/08/24)
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- Process for the preparation of lactic acid or lactate from a magnesium lactate comprising medium
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The present invention relates to an improved process for the preparation of lactic acid and or lactate from a magnesium lactate comprising medium. In said process, magnesium lactate is reacted with a hydroxide of sodium, calcium, and/or ammonium at a pH range between 9 and 12, preferably between 9.9 and 11, to form a lactate of sodium, potassium, calcium and/or ammonia and magnesium hydroxide. With the process according to the invention a lactate salt is formed and magnesium hydroxide. It is essential that said so-called SWAP reaction is conducted within a specific pH range: It was found that when conducting the SWAP reaction at a pH range between 9 and 12 magnesium hydroxide particles are formed which can easily be separated from the lactate salt solution formed.
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Page/Page column 7
(2010/04/30)
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- Selective formation of lactate by oxidation of 1,2-propanediol using gold palladium alloy supported nanocrystals
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The use of bio-renewable resources, such as glycerol, a by-product from bio-diesel manufacture, can provide a viable way to make valuable products using greener technology. In particular, glycerol can be reduced to give 1,2-propanediol that can then be se
- Dimitratos, Nikolaos,Lopez-Sanchez, Jose Antonio,Meenakshisundaram, Sankar,Anthonykutty, Jinto Manjaly,Brett, Gemma,Carley, Albert F.,Taylor, Stuart H.,Knight, David W.,Hutchings, Graham J.
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experimental part
p. 1209 - 1216
(2010/05/17)
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- DIALYSIS SOLUTIONS CONTAINING PYROPHOSPHATES
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Dialysis solutions comprising pyrophosphates and methods of making and using the dialysis solutions are provided. In an embodiment, the present disclosure provides a dialysis solution comprising a stable and therapeutically effective amount of pyrophosphate. The dialysis solution can be sterilized, for example, using a technique such as autoclave, steam, high pressure, ultra-violet, filtration or combination thereof. The dialysis solution can be in the form of a concentrate.
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- PROCESS FOR THE PREPARATION OF LACTIC ACID OR LACTATE FROM A MAGNESIUM LACTATE COMPRISING MEDIUM
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The present invention relates to an improved process for the preparation of lactic acid and or lactate from a magnesium lactate comprising medium. In said process, magnesium lactate is reacted with a hydroxide of sodium, calcium, and/or ammonium at a pH range between 9 and 12, preferably between 9.9 and 11, to form a lactate of sodium, potassium, calcium and/or ammonia and magnesium hydroxide. With the process according to the invention a lactate salt is formed and magnesium hydroxide. It is essential that said so-called SWAP reaction is conducted within a specific pH range: It was found that when conducting the SWAP reaction at a pH range between 9 and 12 magnesium hydroxide particles are formed which can easily be separated from the lactate salt solution formed.
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Page/Page column 13-16
(2008/06/13)
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- Method for producing amines by homogeneously catalyzed reductive amination of carbonyl compounds
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The invention relates to the preparation of chiral or achiral amines by reaction of aldehydes or ketones with ammonia or primary or secondary amines in the presence of hydrogen and in the presence of homogeneous metal catalysts under mild conditions. Metal catalysts which can be used are complexes of late transition metals with chiral or achiral phosphorus-containing ligands.
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Page/Page column 13
(2010/02/11)
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- Carbon exchange in hot alkaline degradation of glucose
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The decomposition of 1-13C-D-glucose, 6-13C-D-glucose, and 1-13C-sodium lactate has been studied in hot (145 ± 3 °C) alkaline (3.5 M) sodium hydroxide solution in order to understand the mechanisms of carbon exchange in th
- Ellis, Amanda V.,Wilson, Michael A.
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p. 8469 - 8474
(2007/10/03)
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- Process for preparing carboxylic acids
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Aliphatic primary alcohols, including aliphatic primary alcohols possessing one or more oxygen, nitrogen and/or phosphorus heteroatoms that may be atoms substituting for carbon atoms in the alkyl group or component atoms of substituents on the alkyl group, were converted into salts of carboxylic acids by contacting an alkaline aqueous solution of the primary alcohol with a catalyst comprising cobalt, copper, and at least one of cerium, iron, zinc, and zirconium. Diethanolamine, for example, was converted to sodium iminodiacetate by treatment in an aqueous medium containing sodium hydroxide with a catalyst that was obtained by reducing a mixture of cobalt, copper, and zirconium oxides with hydrogen.
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- Condensed phase preparation of 2,3-pentanedione
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A condensed phase process for the preparation of purified 2,3-pentanedione from lactic acid and an alkali metal lactate is described. The process uses elevated temperatures between about 200° to 360° C. for heating a reaction mixture of lactic acid and an alkali metal lactate to produce the 2,3-pentanedione in a reaction vessel. The 2,3-pentanedione produced is vaporized from the reaction vessel and condensed with water.
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- Process for producing a carboxylic acid
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A nitrile compound or an amide compound is hydrolyzed in the presence of an inorganic acid or other acidic catalyst or an alkali metal hydroxide or other basic catalyst, and the by-produced ammonium salt of the acidic catalyst or the produced salt of a carboxylic acid and a base is electrodialysed to form an acid and ammonia or aqueous ammonia, or to form a base and ammonia. The obtained acid or base may be recycled as a catalyst for the hydrolysis of the nitrile compound or amide compound, and the obtained ammonia is reutilized as a nitrogen source for the nitrile compound or amide compound. Such amide compound may be produced by hydration of a nitrite compound in the presence of a manganese oxide.
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- Process for preparation of stable aqueous solutions of zirconium chelates
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Aqueous solutions of zirconium chelates are prepared by combining an alpha-hydroxycarboxylic acid salt with a solution of a zirconium compound. That preparation first involves formulating an alpha-hydroxycarboxylic acid salt through a stoichiometric reaction between an alpha-hydroxycarboxylic acids and a base. The stoichiometric reaction product consists of an approximately neutral solution of a corresponding alpha-hydroxycarboxylic acid salt. The alpha-hydroxycarboxylic acid salt is then added to a solution of a zirconium compound to produce a mildly acidic or basic solution of the corresponding zirconium alpha-hydroxycarboxylic chelate. Alternatively, the alpha-hydroxycarboxylic acid salt may be pre-prepared and added in solid or liquid form to the zirconium compound before the zirconium compound is placed in solution so that the corresponding zirconium alpha-hydroxycarboxylic chelate is produced.
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- Process for preparation of stable aqueous solutions of zirconium chelates
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The present invention comprises reacting ammonium, sodium or potassium hydroxide or water soluble amines or amine derivatives with alpha-hydroxy carboxylic acid to prepare a neutral solution of the corresponding alpha-hydroxy carboxylic salt in a stoichiometric reaction. The alkali metal, ammonium, amine or amine derivative, alpha-hydroxy carboxylic acid salt is then added to solutions of zirconium which may be zirconium oxychloride, zirconium hydroxy chloride, zirconium acetate and the like, ammonia, water soluble amines or amine derivatives, diisopropylamine or a mixture of two or more of these bases, as well as soluble carbonates and/or bicarbonates of ammonium and alkali metals such as sodium and potassium, while mixing the solutions. The procedure produces a mildly acidic or basic solution of the zirconium alpha-hydroxy carboxylic chelate.
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