Three-Component Ring Transformation Using
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Amide Bond Formation and Peptide Coupling
Tetrahedron 61 (2005) 10827–10852 Tetrahedron report number 740 Amide bond formation and peptide coupling Christian A. G. N. Montalbetti* and Virginie Falque Evotec, 112 Milton Park, Abingdon OX14 4SD, UK Received 2 August 2005 Available online 19 September 2005 Contents 1. Introduction ................................................................. 10828 2. Amide bond formation: methods and strategies ....................................... 10828 2.1. Acyl halides . .......................................................... 10829 2.1.1. Acyl chlorides .................................................... 10829 2.1.1.1. Acyl chloride formation ...................................... 10829 2.1.1.2. Coupling reactions with acyl chlorides ........................... 10831 2.1.1.3. Limitations of acyl chlorides .................................. 10831 2.1.2. Acyl fluorides .................................................... 10831 2.1.3. Acyl bromides .................................................... 10832 2.2. Acyl azides . .......................................................... 10832 2.3. Acylimidazoles using CDI ................................................. 10833 2.4. Anhydrides . .......................................................... 10834 2.4.1. Symmetric anhydrides .............................................. 10834 2.4.2. Mixed anhydrides .................................................. 10834 2.4.2.1. Mixed carboxylic anhydrides .................................. 10834 2.4.2.2. Mixed carbonic anhydrides ................................... -
215-216 HH W12-Notes-Ch 15
Chem 215 F12 Notes Notes – Dr. Masato Koreeda - Page 1 of 17. Date: October 5, 2012 Chapter 15: Carboxylic Acids and Their Derivatives and 21.3 B, C/21.5 A “Acyl-Transfer Reactions” I. Introduction Examples: note: R could be "H" R Z R O H R O R' ester O carboxylic acid O O an acyl group bonded to R X R S acid halide* R' an electronegative atom (Z) thioester O X = halogen O R' R, R', R": alkyl, alkenyl, alkynyl, R O R' R N or aryl group R" amide O O O acid anhydride one of or both of R' and R" * acid halides could be "H" R F R Cl R Br R I O O O O acid fluoride acid chloride acid bromide acid iodide R Z sp2 hybridized; trigonal planar making it relatively "uncrowded" O The electronegative O atom polarizes the C=O group, making the C=O carbon "electrophilic." Resonance contribution by Z δ * R Z R Z R Z R Z C C C C O O O δ O hybrid structure The basicity and size of Z determine how much this resonance structure contributes to the hybrid. * The more basic Z is, the more it donates its electron pair, and the more resonance structure * contributes to the hybrid. similar basicity O R' Cl OH OR' NR'R" Trends in basicity: O weakest increasing basiciy strongest base base Check the pKa values of the conjugate acids of these bases. Chem 215 F12 Notes Notes –Dr. Masato Koreeda - Page 2 of 17. -
21.1 Introduction Carboxylic Acids 21.1 Introduction Carboxylic Acids
4/25/2012 21.1 Introduction Carboxylic Acids 21.1 Introduction Carboxylic Acids • Carboxylic acids are abundant in nature and in • The US produces over 2.5 million tons of acetic acid per pharmaceuticals. year, which is primarily used to produce vinyl acetate. – Vinyl acetate is used in paints and adhesives. • Carboxylic acid derivatives, such as vinyl acetate, are very common, and they play a central role in organic chemistry. Copyright 2012 John Wiley & Sons, Inc. 21-1 Klein, Organic Chemistry 1e Copyright 2012 John Wiley & Sons, Inc. 21-2 Klein, Organic Chemistry 1e 21.2 Nomenclature of Carboxylic 21.2 Nomenclature of Carboxylic Acids Acids • Monocarboxylic acids are named with the suffix • When the carboxylic acid group is “oic acid.” attached to a ring, it is named as an alkane carboxylic acid. • There are also many common names for carboxylic acids. • The carbon of the carboxylic acid moiety is assigned the locant position 1. Copyright 2012 John Wiley & Sons, Inc. 21-3 Klein, Organic Chemistry 1e Copyright 2012 John Wiley & Sons, Inc. 21-4 Klein, Organic Chemistry 1e 21.2 Nomenclature of Carboxylic 21.3 Structure and Properties of Acids Carboxylic Acids • Dicarboxylic acids are named with • The carbon atom of the carboxylic acid the suffix “dioic acid.” has a trigonal planar geometry. WHY? • There are also many common names for dicarboxylic • The acid moiety is capable of strong hydrogen (H‐) acids: bonding including H‐bonding between acid pairs. • As a result, carboxylic acids generally have high boiling points. • Practice with CONCEPTUAL CHECKPOINTs – Consider the BPs of acetic acid (118 °C) and 12.1 through 12.3. -
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. -