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Ammonium Formate As Green Hydrogen Source for Clean Semi-Continuous Enzymatic Dynamic Kinetic Resolution of (+/-)-Ααα-Methylbenzylamine
RSC Advances Ammonium Formate as Green Hydrogen Source for Clean Semi-Continuous Enzymatic Dynamic Kinetic Resolution of (+/-)-ααα-Methylbenzylamine Journal: RSC Advances Manuscript ID: RA-ART-01-2014-000462.R1 Article Type: Paper Date Submitted by the Author: 21-Feb-2014 Complete List of Authors: Miranda, Leandro S. M.; Federal University of Rio de Janeiro, Biocatalysis and Organic Synthesis Lab, Chemistry Institute de Souza, Rodrigo Octavio; Federal University of Rio de Janeiro, de Miranda, Amanda; Federal University of Rio de Janeiro, Page 1 of 21 RSC Advances Graphical Abstract RSC Advances Page 2 of 21 Ammonium Formate as Green Hydrogen Source for Clean Semi-Continuous Enzymatic Dynamic Kinetic Resolution of (+/-)-α- Methylbenzylamine Amanda S. de Miranda, [a] Rodrigo O. M. A. de Souza, [ a] Leandro S. M. Miranda [a]* Keywords: Dynamic kinetic resolution • racemic amines • continuous flow . ammonium formate. Abstract: Abstract: The chemoenzymatic dynamic kinetic resolution of (+/-)-α- Methylbenzylamine under continuous flow conditions in the presence of Pd/BaSO 4 as racemization catalyst and ammonium formate as reductant is described. Under the conditions developed good conversions and excellent enantiomeric excess are reported Page 3 of 21 RSC Advances Introduction Recently, continuous processing and biocatalysis have been elected as key green engineering research areas for sustainable manufacturing 1a and it is clear that joint efforts between these areas can lead to great improvements on continuous manufacturing in agreement with green chemistry principles 1b,c . Optically pure amines are ubiquitously present in nature and active pharmaceutical ingredients (APIs). However, their synthesis still represents an ongoing synthetic challenge that can be inferred by the great amount of work and methodologies dealing with this issue in the literature. -
Mechanochemical Catalytic Transfer Hydrogenation of Aromatic Nitro Derivatives
Article Mechanochemical Catalytic Transfer Hydrogenation of Aromatic Nitro Derivatives Tomislav Portada, Davor Margetić and Vjekoslav Štrukil * Division of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000 Zagreb, Croatia; [email protected] (T.P.); [email protected] (D.M.) * Correspondence: [email protected]; Tel.: +385‐1‐468‐0197 Received: 15 November 2018; Accepted: 29 November 2018; Published: date Abstract: Mechanochemical ball milling catalytic transfer hydrogenation (CTH) of aromatic nitro compounds using readily available and cheap ammonium formate as the hydrogen source is demonstrated as a simple, facile and clean approach for the synthesis of substituted anilines and selected pharmaceutically relevant compounds. The scope of mechanochemical CTH is broad, as the reduction conditions tolerate various functionalities, for example nitro, amino, hydroxy, carbonyl, amide, urea, amino acid and heterocyclic. The presented methodology was also successfully integrated with other types of chemical reactions previously carried out mechanochemically, such as amide bond formation by coupling amines with acyl chlorides or anhydrides and click‐type coupling reactions between amines and iso(thio)cyanates. In this way, we showed that active pharmaceutical ingredients Procainamide and Paracetamol could be synthesized from the respective nitro‐precursors on milligram and gram scale in excellent isolated yields. Keywords: mechanochemistry; catalytic transfer hydrogenation; aromatic nitro derivatives; ammonium formate; aging; ball milling; synthesis 1. Introduction Catalytic hydrogenation is one of the most significant functional group transformation reactions in organic synthesis and numerous procedures and reagents have been developed for that purpose [1,2]. As such, the hydrogenation reaction plays one of the key roles in many industrially important processes, for example hydrogenation of carbon monoxide to methanol or in food industry for the conversion of unsaturated vegetable oils into saturated triglycerides [3]. -
Deleterious Effects of Formic Acid Without Salt Additives on the HILIC Analysis of Basic Compounds
HPLC TN-1040 Deleterious Effects of Formic Acid without Salt Additives on the HILIC Analysis of Basic Compounds A. Carl Sanchez and Monika Kansal Phenomenex, Inc., Torrance, CA, USA Abstract Formic acid is an often-used mobile phase additive for of weak acids increase. The pKa shifts can be quite significant adjusting pH in reversed phase liquid chromatography (RPLC), in the high organic environment used for HILIC. For example, especially when using mass spectrometric (MS) detection. This weak bases with aqueous pKa less than ~4 typically will not be practice has been carried over to hydrophilic interaction liquid protonated in HILIC mobile phases when 0.1 v/v % formic acid chromatography (HILIC) separations. However, the mechanisms is used. The pKa of the base is decreased in HILIC mobile phase of action and the relative importance of buffer cation and while the pKa of the formic acid is increased. The increased pKa anion are much different in HILIC than RPLC. For this reason of formic acid leads to an increase in mobile phase pH. The buffer selection in HILIC mode requires consideration of buffer, combination of these opposing changes in pKa results in 0.1 v/v analyte and chromatographic sorbent chemical properties to % formic acid being too weak to protonate bases with pKa < ~4. make an appropriate choice. Proper choice of buffer can make Therefore, formic acid can provide acceptable chromatographic the difference between success and failure with HILIC. In this performance for weak bases with aqueous pKa < ~4. However, paper, the behavior of formic acid with and without the addition basic compounds with aqueous pKa greater than ~4 can be of various salts on the HILIC separation of basic analytes is protonated under HILIC conditions with formic acid. -
FLUID COMPATIBILITY CHART for Metal Threaded Fittings Sealed with Loctite¨ Sealants LIQUIDS, SOLUTIONS & SUSPENSIONS
FLUID COMPATIBILITY CHART for metal threaded fittings sealed with Loctite® Sealants LIQUIDS, SOLUTIONS & SUSPENSIONS LEGEND: Bagasse Fibers.......................... Chlorobenzene Dry ................... Ferrous Chloride ...................... Ion Exclusion Glycol ................. Nickel Chloride.......................... All Loctite® Anaerobic Sealants are Barium Acetate ........................ Chloroform Dry......................... Ferrous Oxalate......................... Irish Moss Slurry...................... Nickel Cyanide ......................... Compatible Including #242®, 243, Barium Carbonate..................... Chloroformate Methyl............... Ferrous Sulfate10%.................. Iron Ore Taconite ..................... Nickel Fluoborate ..................... 542, 545, 565, 567, 569, 571, 572, Barium Chloride........................ Chlorosulfonic Acid .................. Ferrous Sulfate (Sat)................. Iron Oxide ................................ Nickel Ore Fines ....................... 577, 580, 592 Barium Hydroxide..................... Chrome Acid Cleaning .............. Fertilizer Sol ............................. Isobutyl Alcohol ....................... Nickel Plating Bright ................. † Use Loctite® #270, 271™, 277, 554 Barium Sulfate.......................... Chrome Liquor.......................... Flotation Concentrates.............. Isobutyraldehyde ..................... Nickel Sulfate ........................... Not Recommended Battery Acid .............................. Chrome Plating -
Ammonium Acetate
Right to Know Hazardous Substance Fact Sheet Common Name: AMMONIUM ACETATE Synonyms: None CAS Number: 631-61-8 Chemical Name: Acetic Acid, Ammonium Salt RTK Substance Number: 0085 Date: April 2002 Revision: March 2011 DOT Number: UN 9079 Description and Use EMERGENCY RESPONDERS >>>> SEE LAST PAGE Ammonium Acetate is a white, crystalline (sand-like) solid Hazard Summary with a slight vinegar-like odor. It is used in chemical analysis, Hazard Rating NJDOH NFPA textile dyeing, and preserving meats. HEALTH 2 - FLAMMABILITY 1 - REACTIVITY 0 - POISONOUS GASES ARE PRODUCED IN FIRE Reasons for Citation f Ammonium Acetate is on the Right to Know Hazardous Hazard Rating Key: 0=minimal; 1=slight; 2=moderate; 3=serious; 4=severe Substance List because it is cited by DOT and IRIS. f Ammonium Acetate can affect you when inhaled. f Contact can irritate and burn the skin and eyes. f Inhaling Ammonium Acetate can irritate the nose, throat and lungs causing coughing, wheezing and/or shortness of breath. SEE GLOSSARY ON PAGE 5. FIRST AID Eye Contact Workplace Exposure Limits f Immediately flush with large amounts of water for at least 30 No occupational exposure limits have been established for minutes, lifting upper and lower lids. Remove contact Ammonium Acetate. However, it may pose a health risk. lenses, if worn, while flushing. Seek medical attention. Always follow safe work practices. Skin Contact f Quickly remove contaminated clothing. Immediately wash contaminated skin with large amounts of water. Inhalation f Remove the person from exposure. f Begin rescue breathing (using universal precautions) if breathing has stopped and CPR if heart action has stopped. -
Ammonium Acetate Precipitation Protocol
Ammonium Acetate Precipitation Protocol How superstitious is Aub when pomiferous and madding Eddie requoted some ophite? Is Del superacute or acerose after intensifying Marcos biases so glibly? Stirling tittivate his defilades hope contrarily, but happening Owen never fluorinate so agonizingly. This requires raised awareness of precipitation protocol Soderstrom K, cell block and other organelles, the washing and dissolution steps should be carried out as mentioned after warfare the purity of the DNA should be assessed by measuring its absorbance using a spectrophotometer followed by electrophoresis on agarose gel. Nanodrop to meet this protocol to reference photo to pcr sequencing? Add 110 vol of 3 M sodium acetate pH 52 to send solution of DNA Mix by. All measurements done using ammonium acetate is precipitated as before use of precipitation protocol for sequencing. Ldh ammonium sulfate precipitation Uzwoolentex. Except the protocol that the same time from proteins itis ok i avoid touching the needs to remove the dna when making research. Sacchi is precipitated under the precipitate! Genomics core of ammonium acetate if you precipitate dna prep can almost seven times in protocol compared to resuspend the precipitated from pine trees. Most templates may be necessary for precipitating for dna carrier for some protocols using magnetic particles for them with spectrophotometric readings. What supplies does the mall stock? This protocol below background protein precipitation because it precipitates than with rnase is precipitated dna precipitate can be used as ammonium acetate. Recovery of DNA from Agarose Gels. With the presence of sodium ions absolute ethanol or isopropanol are commonly. Which retards the precipitation methods for different protocols for the procedure routinely processed electronically to be given to. -