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14: Reactions with stabilized carbanion intermediates, part II

  • Page ID
    984
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    A complete PDF version of Organic Chemistry With a Biological Emphasis is available here as a free download.

     

    We saw in Chapter 13 how stabilized carbanions - enols, enolated enamines - are key intermediates in biological isomerization reactions and in carbon-carbon bond-forming and bond-breaking events. In this chapter, we will look at two more important reaction types, called Michael additions and β-eliminations, which involve stabilized carbanion species as intermediates. In a Michael addition, a nucleophile and a proton are 'added' to the two carbons of an alkene that is conjugated to a carbonyl. In a beta-elimination, the reverse process occurs:

     

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    The rich and fascinating chemistry of coenzymes plays a large role in this chapter. We will examine several carbanion-intermediate reactions that involve the participation of pyridoxal phosphate (vitamin B6), a very important carbanion-stabilizing coenzyme. Finally, we will see how the coenzyme thiamine (vitamin B1) allows a carbonyl carbon to act as the nucleophile in a unique class of carbon-carbon bond-forming reaction.

    Organic Chemistry With a Biological Emphasis by Tim Soderberg (University of Minnesota, Morris)


    This page titled 14: Reactions with stabilized carbanion intermediates, part II is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.


    This page titled 14: Reactions with stabilized carbanion intermediates, part II is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Tim Soderberg via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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