Diels-Alder Reaction: Endo Pre-coordination Complex between
E-1,3-Pentadiene and Maleic Anhydride


The precoordination complex of the endo cycloaddition of E-1,3-pentadiene and maleic anhydride. Van der Waals interactions hold this complex together and it is about 7.4 kcal/mol more stable than the isolated substrates. Note that there is a small preference of 0.4 kcal/mol for this endo arrangement over the exo arrangement.


Figure. The MP2(full)/6-31G* optimized precoordination complex of the endo cycloaddition of E-1,3-Pentadiene and Maleic Anhydride.