The oxo-dielsalder reaction is a particular case of the dielsalder reaction, wherein an oxygen atom (as heteroatom) is part of the dienophile (as a carbonyl group). Dihydropyran derivatives are deformed:
The first oxo-diels-age reaction, published in 1949, used 2-methyl-1,3-pentadiene and formaldehyde as reactants:
The reaction works quite well when the carbonyl group is in the dienophile electron arm, by the presence of electron withdrawing substituents. An example of a good dienophile is carbonyldicyanide. Also see
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