Download Examples of Reactions with Grignard Reagents

Examples of Reactions with
Grignard Reagents
•
Numbers above and below arrows mean the acid is not added until
the Grignard reagent has reacted with the carbonyl compound.
•
When a reaction creates an asymmetric center from achiral reactants
the product is a racemic mixture.
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Enzyme-Catalyzed Carbonyl Additions
•  If a product with an asymmetric center is formed in an enzyme-catalyzed
reaction, only one enantiomer will be formed.
•  The enzyme blocks one face of the carbonyl compound so that only
the other face is available for attack.
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Esters React with Grignard Reagents
to Form Alcohols
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Acyl Chlorides React with Grignard Reagents
to Form Alcohols
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Retrosynthetic Analysis
•
Work backwards to decide what alcohol and alkyl bromide could be used
to synthesize a ketone.
• Write the reaction scheme with all reagents and conditions.
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Reaction of Acetylide Ions
with Carbonyl Compounds
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Reaction of Aldehydes and Ketones
with Cyanide Ion
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Reactions of Cyanohydrins
In base,
decomposition to the
carbonyl compound.
In acid, hydrolysis to an
α-hydroxycarboxylic acid.
Reduction to a primary
amine with an OH group
on the β-carbon.
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Reactions of Aldehydes and Ketones
with Hydride Ion
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Reactions of Acyl Chlorides
with Hydride Ion
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A Weak Hydride Donor Reduces
an Acyl Chloride to an Aldehyde
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Reactions of Esters with Hydride Ion
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Reactions of Carboxylic Acids
with Hydride Ion
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A Weak Hydride Donor Reduces
an Ester to an Aldehyde
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The Reactions of Amides
with Hydride Ion
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Mechanism for the Reaction of an
N-Substituted Amide with Hydride Ion
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Reductions Happen in Different Ways
•  An organic compound is reduced when hydrogen is added to it.
•  Hydrogen can be added as a hydride ion and a proton.
•  Hydrogen can be added as two hydrogen atoms.
•  Hydrogen can be added as two electrons and two protons.
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Hydrogen Can Be Added
as a Hydride Ion and a Proton
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Catalytic Hydrogenation Reduces
Carbon—Carbon Double and Triple Bonds
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Catalytic Hydrogenation Reduces
Carbon—Nitrogen Double and Triple Bonds
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