• Study Resource
  • Explore Categories
    • Arts & Humanities
    • Business
    • Engineering & Technology
    • Foreign Language
    • History
    • Math
    • Science
    • Social Science

    Top subcategories

    • Advanced Math
    • Algebra
    • Basic Math
    • Calculus
    • Geometry
    • Linear Algebra
    • Pre-Algebra
    • Pre-Calculus
    • Statistics And Probability
    • Trigonometry
    • other →

    Top subcategories

    • Astronomy
    • Astrophysics
    • Biology
    • Chemistry
    • Earth Science
    • Environmental Science
    • Health Science
    • Physics
    • other →

    Top subcategories

    • Anthropology
    • Law
    • Political Science
    • Psychology
    • Sociology
    • other →

    Top subcategories

    • Accounting
    • Economics
    • Finance
    • Management
    • other →

    Top subcategories

    • Aerospace Engineering
    • Bioengineering
    • Chemical Engineering
    • Civil Engineering
    • Computer Science
    • Electrical Engineering
    • Industrial Engineering
    • Mechanical Engineering
    • Web Design
    • other →

    Top subcategories

    • Architecture
    • Communications
    • English
    • Gender Studies
    • Music
    • Performing Arts
    • Philosophy
    • Religious Studies
    • Writing
    • other →

    Top subcategories

    • Ancient History
    • European History
    • US History
    • World History
    • other →

    Top subcategories

    • Croatian
    • Czech
    • Finnish
    • Greek
    • Hindi
    • Japanese
    • Korean
    • Persian
    • Swedish
    • Turkish
    • other →
 
Profile Documents Logout
Upload
Organic Compounds Containing C, H and O
Organic Compounds Containing C, H and O

... Ans. i. a. Nitro (-NO2) group is an electron withdrawing whereas methoxy (-OCH3) group is electron releasing in nature. o-nitrophenol produces H+ ions easily but methoxyphenol does not. This is because o-nitrophenoxide ion is stabilised due to resonance. This is not true with o-methoxyphenoxide ion. ...
Organic Chemistry II
Organic Chemistry II

... Acetals can act as protecting groups for aldehydes and ketones in basic solutions due to their stability  For instance, to protect a carbonyl group, one can add a cyclic acetal in HCl. Then one can perform the desired reaction without worrying about the carbonyl group. Finally, to remove the cyclic ...
INTRODUCTION
INTRODUCTION

... Second generation breathalyzer tests measure the amount of water produced in the reaction, for a more accurate measure. Secondary alcohols (OH attached to a non-terminal carbon) may be oxidized in a single stage to the corresponding ketone. The general reaction is: secondary alcohol + oxidizing agen ...
Demonstrate skill in organic chemistry techniques.
Demonstrate skill in organic chemistry techniques.

... Organic Chemistry I is the first course in a two semester sequence which covers the structure, stereochemistry, physical properties, reactivity, reaction mechanisms and synthesis of carbon-containing compounds. Emphasis on alkanes, alkenes, alkynes, alcohols, alkyl halides, aldehydes, ketones, and c ...
Aldehydes and Ketones
Aldehydes and Ketones

... g) Addition of derivatives of Ammonia (Formation of imine).  Treatment of an aldehyde or ketone with a 1° amine affords an imine (also called a Schiff base).  Nucleophilic attack of the 1° amine on the carbonyl group forms an unstable carbinolamine, which loses water to form an imine. The overal ...
This exam will consist of 30-35 multiple choice or short answer
This exam will consist of 30-35 multiple choice or short answer

... What are some physical properties of the starting materials and product? What is petroleum ether? What is the purpose of using pet ether in this experiment? What is the mechanism of the reaction? Why must the reaction apparatus be dry? What happens if water is present? How are the theoretical and pe ...
Solutions
Solutions

... in a tautomeric form different from the one I usually draw, so that N9 is not protonated). ...
Demonstrate skill in organic chemistry techniques.
Demonstrate skill in organic chemistry techniques.

... Organic Chemistry I is the first course in a two semester sequence which covers the structure, stereochemistry, physical properties, reactivity, reaction mechanisms and synthesis of carbon-containing compounds. Emphasis on alkanes, alkenes, alkynes, alcohols, alkyl halides, aldehydes, ketones, and c ...
Organic Chemistry - Snow College | It's SNOWing
Organic Chemistry - Snow College | It's SNOWing

... (2.5) and H (2.1) is 0.4. • This creates a bond with low polarity • show little association by hydrogen bonding • have lower boiling points and are less soluble in water than alcohols of comparable MW ...
Chapter 19: Carboxylic Acid Derivatives
Chapter 19: Carboxylic Acid Derivatives

... Nucleophilic acyl substitution reactions of esters (Table 19.4). Esters are less reactive toward nucleophilic acyl substitution than acid chlorides or acid anhydrides. 1. Aminolysis (Ch.19.11): Esters react with ammonia, 1° and 2° amines to give amides ...
Chapter 14 – Aldehydes and Ketones
Chapter 14 – Aldehydes and Ketones

... In the presence of a large excess of water, the reaction will run in reverse. (When comparable amounts of water and alcohol are present the reaction is an equilibrium.) This is how the cyclic (hemiacetal) form of D-glucose polymerizes to form a carbohydrate chain. Have you ever noticed that if you c ...
Ethers, Sulfides, Epoxides - City University of New York
Ethers, Sulfides, Epoxides - City University of New York

... alcohol can set-up a better leaving group. Protonation of a carbonyl can create a ...
Table of K Values a pK
Table of K Values a pK

... Aldehyde ...
Addition of ketene to ethylene oxide
Addition of ketene to ethylene oxide

phenol - Knockhardy
phenol - Knockhardy

... • the OH group is electron releasing • it increases the electron density of the delocalised system • it makes substitution much easier compared to benzene • the electron density is greatest at the 2,4 and 6 positions • substitution takes place at the 2,4 and 6 positions • phenol reacts readily with ...
Epoxyalkyl peptide derivatives as active-site
Epoxyalkyl peptide derivatives as active-site

... strategically favoured position for a reaction with an amino acid side chain at the active site. They were prepared by epoxidation with p-chloroperbenzoic acid from their corresponding olefinic peptide precursors. The latter compounds were synthesized by Abbreviation used: OMe, methoxy (methyl ester ...
Chapter 12 - Alcohols from Carbonyl Compounds1
Chapter 12 - Alcohols from Carbonyl Compounds1

... 12.6 - Preparation of Organolithium and Organomagnesium Compounds - The general reaction to create organolithium compounds is, RX + 2 Li −→ RLi + LiX - Grignard reagents are organomagnesium halides and are prepared by, RX + Mg −→ RMgX 12.7 - Reactions of Organolithium and Organomagnesium Compounds - ...
Mechanism of Aldol Condensation
Mechanism of Aldol Condensation

... Aldol condensations are important in organic synthesis, providing a good way to form carbon– carbon bonds. For example, the Robinson annulation reaction sequence features an aldol condensation; the Wieland-Miescher ketone product is an important starting material for many organic syntheses. Aldol co ...
Syn Addition
Syn Addition

... Alkene must be 2-butene. But wait that could be either cis or trans! We want meso. Have to worry about stereochemistry ...
Chapter 1--Title
Chapter 1--Title

...  The Kolbe Reaction  Carbon dioxide is the electrophile for an electrophilic aromatic substitution with phenoxide anion ...
ESTERIFICATION
ESTERIFICATION

... flavor chemists often use esters, either one or several, to reproduce or enhance natural flavors. The table on the next page shows some examples of esters that are primary components of various odors and flavors. You will choose one of these esters to synthesize. Although esters are often used as fl ...
Organic Chemistry I Laboratory
Organic Chemistry I Laboratory

... isolated. Because only a very small percentage of the menthyl chloride molecules are in the less stable conformation at any time, the reaction is much slower than the reaction of neomenthyl chloride. This example shows that whenever a substrate yields the less stable alkene as a major product of an ...
ORGANIC REACTIONS IN A CLAY MICROENVIRONMENT
ORGANIC REACTIONS IN A CLAY MICROENVIRONMENT

OChem 1 Mechanism Flashcards Dr. Peter Norris, 2015
OChem 1 Mechanism Flashcards Dr. Peter Norris, 2015

... Acid-Base reactions are generally very fast (proton, H, is accessible) ...
Answers to “Tragic Flaws” 1. Can`t form an ether using an alcohol
Answers to “Tragic Flaws” 1. Can`t form an ether using an alcohol

... using POCl3 with pyridine – no control over which way the double bond will form – both sides would form a trisubstituted alkene. Multiple products! 13. Grignard additions form alcohols. Not ketones. Missing an oxidation in the sequence. 14. Tragic flaws all over the place. Need ketone FIRST to do co ...
< 1 ... 44 45 46 47 48 49 50 51 52 ... 65 >

Wolff rearrangement



The Wolff rearrangement is a reaction in organic chemistry in which an α-diazocarbonyl compound is converted into a ketene by loss of dinitrogen with accompanying 1,2-rearrangement. The Wolff rearrangement yields a ketene as an intermediate product, which can undergo nucleophilic attack with weakly acidic nucleophiles such as water, alcohols, and amines, to generate carboxylic acid derivatives or undergo [2+2] cycloaddition reactions to form four-membered rings. The mechanism of the Wolff rearrangement has been the subject of debate since its first use. No single mechanism sufficiently describes the reaction, and there are often competing concerted and carbene-mediated pathways; for simplicity, only the textbook, concerted mechanism is shown below. The reaction was discovered by Ludwig Wolff in 1902. The Wolff rearrangement has great synthetic utility due to the accessibility of α-diazocarbonyl compounds, variety of reactions from the ketene intermediate, and stereochemical retention of the migrating group. However, the Wolff rearrangement has limitations due to the highly reactive nature of α-diazocarbonyl compounds, which can undergo a variety of competing reactions.The Wolff rearrangement can be induced via thermolysis, photolysis, or transition metal catalysis. In this last case, the reaction is sensitive to the transition metal; silver (I) oxide or other Ag(I) catalysts work well and are generally used. The Wolff rearrangement has been used in many total syntheses; the most common use is trapping the ketene intermediate with nucleophiles to form carboxylic acid derivatives. The Arndt-Eistert homologation is a specific example of this use, wherein a carboxylic acid may be elongated by a methylene unit. Another common use is in ring-contraction methods; if the α-diazo ketone is cyclic, the Wolff rearrangement results in a ring-contracted product. The Wolff rearrangement works well in generating ring-strained systems, where other reactions may fail.
  • studyres.com © 2025
  • DMCA
  • Privacy
  • Terms
  • Report