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 Chapter 18: Enols and Enolates 
Ch 18 contents
Conjugate Addition with Organocopper reagents

conjugate addition of organocopper reagents

Reaction type : Nucleophilic Addition

Summary

STUDY TIPS:
  • Remember that like enolates, organometallic compounds are a source of nucleophilic C systems   e.g. RMgX is equivalent to R-
  • So it is "useful" to impose ionic character on organometallics e.g. RMgX is equivalent to R- Mg2+ X- or  R2CuLi is equivalent to (R-)2 Cu+ Li+

 

Related reactions

MECHANISM OF THE ORGANOCUPRATE ADDITION*
Step 1:
The nucleophilic C in the cuprate attacks the conjugated ketone at the electrophilic alkene C in a nucleophilic addition type process with the electrons being pushed through to the electronegative O, giving an intermediate enolate.
mechanism of the conjugate addition of a cuprate

Step 2:
On acidic work-up, the enolate is protonated at the α-C  creating the more favourable carbonyl group.
 
 

* This is a simplified representation of the mechanism

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© Dr. Ian Hunt, Department of Chemistry, University of Calgary