diels - alder reaction

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ORGANIC CHEMISTRY
CYCLIC ADDITION DIELS ALDER REACTION
PROF.DR . NAZ M ATABAY DEPARTMENT OF CHEMISTRY
FATIH UNIVERSITY
MSc.student . NABEEL B AZEEZ
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OUTLINES

• INTRODUCTION
• THE REACTION
• REACTION MECHANISM
• STEREOSELECTIVITY
• RETROSYNTHETIC ANALYSIS
• RECENT LITERATURE
• REFRENCES

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1950
Kurt Alder
Otto Diels
Diels-Alder Reaction
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INTRODUCTION

• diene synthesis has developed into one of the
  most important working methods in organic
  chemistry .
• The method has also proved valuable in a great
  many ways in research into the constitution of
  complex natural products .
• formed by diene synthesis are usually stable.

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DIELS ALDER REACTION
The reaction is taken place between a
conjugated diene and a substituted alkene,
commonly termed the dienophile, to form a
substituted cyclohexene system
conjugated diene
cyclohexene
dienophile
The DielsAlder reaction is particularly useful
in synthetic organic chemistry as a reliable
method for forming 6-membered systems with good
control over regio- and stereo chemical
properties. The underlying concept has also been
applied to other p-systems, such
as carbonyls and imines, to furnish the
corresponding heterocyclic, known as
the hetero-DielsAlder reaction. DielsAlder
reactions can be reversible under certain
conditions the reverse reaction is known as
the retro-DielsAlder reaction.
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THE MECHANISM
A conjugated diene reacts with a double-bonded
dienophile
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THE MECHANISM
Normally, dienes are electron-rich dienophiles
are electron-poor
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THE MECHANISM
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STEREOSELECTIVITY

• DielsAlder reactions, as concerted
  cycloadditions, are tereospecific, i.e. stereo
  chemical information in the reactants is retained
  in the products. E- and Z-dienophiles, for
  example, give rise to the adducts with
  corresponding syn or anti-stereochemistry

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STEREOSELECTIVITY
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Retro synthetic analysis using the Diels-Alder
reaction
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RECENT LITERATURE
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References

• Organic chemistry Clayden, J. Greeves, N.
  Warren, S. Wothers, P. Oxford University Press,
  Oxford, 2006.
• Lewis Acids and Selectivity in Organic
  Synthesis Santelli, M. Pons, J. CRS Press, USA,
  1995. \ http//www.organic-chemistry.org/namedrea
  ctions/diels-alder-reaction.shtm
• Wikipedia.co.uk

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