Diels-Alder Reaction

Cyclohexenes from Dienes and Dienophiles

The Basic Diels-Alder Reaction:

The Diels-Alder reaction is a simultaneous movement of 6 electrons, breaking 3 bonds and forming 3 new bonds. The blue color in the product shows the new bonds. In the Diels-Alder reaction written in the forward direction as above, there is a loss of 3 pi bonds and a gain of one new pi bond and two new sigma bonds. This accounts for the general favorability of the reaction as written, but it does not prevent the reaction from running in reverse.

Common Diels-Alder Dienes.

Note the cisoid conformation required for successful Diels-Alder reaction. The terminal carbons of each diene are the ones involved in the formation of the new bonds.

Common Diels-Alder Dieneophiles.

Note electron-withdrawing groups.

Example Products

3-D images of the products B+N and D+O are available, if you have Chime or Rasmol configured to help you look at PDB files.

Stereoselectivity of the Diels-Alder reaction

The Diels-Alder reaction is very stereoselective. For a discussion of this stereoselectivity, click on over to the Diels-Alder Reaction Stereochemistry page. Specific topics on the stereochemistry page are: