CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC...
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ORGANIC - BROWN 8E
CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
CONCEPT: NUCLEOPHILIC ADDITION
□ One of the most important ways that carbonyl compounds react is through nucleophilic addition.
● The carbonyl carbon is _____________________________
Nucleophilic Addition General Mechanism:
Nucleophilic Addition General Reactions:
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CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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CONCEPT: PREPARATION OF ORGANOMETALLICS
□ Organometallics are alkylating agents that have mostly group IA or group IIA metals bonded to a carbon structure
● They can also react as strong ____________. Beware of cross-reactions with acidic hydrogens.
1. Sodium Alkynides
2. Grignard Reagents
3. Organolithium Reagents
4. Gilman Reagents
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CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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CONCEPT: REACTIONS OF ORGANOMETALLICS
1. Substitution/Elimination on Alkyl Halides
2. Nucleophilic Addition on Ketones and Aldehydes
3. Nucleophilic Acyl Substitution on Esters
4. Base-Catalyzed Epoxide Ring Opening
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CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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CONCEPT: USE OF PROTECTING GROUPS
□ Organometallics are powerful bases. They will react with any acidic protons available, ruining the reagent.
We can use tert-butyl or silyl ethers to protect alcohols from deprotonation by organometallic reagents
● p-Toluenesulfonic acid is an acid commonly used for this step (abbrev. TsOH or pTSA)
EXAMPLE: Provide the mechanism and final product for the following transformation
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CONCEPT: CYCLOPROPANATION
□ Carbenes are reactive intermediates. They are unstable because they violate the ___________ ___________.
□ There are 4 methods commonly used to introduce carbene intermediates:
1.
2.
3.
4.
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CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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PRACTICE: Predict the product of the following reaction.
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CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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PRACTICE: Predict the product of the following reaction.
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CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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PRACTICE: Predict the product of the following reaction.
ORGANIC - BROWN 8E
CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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PRACTICE: Predict the product of the following reaction.
ORGANIC - BROWN 8E
CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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PRACTICE: Propose a synthesis to accomplish the following transformation.
ORGANIC - BROWN 8E
CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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PRACTICE: Propose a synthesis to accomplish the following transformation.
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CH. 15 - AN INTRODUCTION TO ORGANOMETALLIC COMPOUNDS
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PRACTICE: Propose a synthesis to accomplish the following transformation (Hint: 4 steps)
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