Diels-Alder reactions autocatalytic

Wang and Sutherland95 communicated an autocatalytic Diels-Alder reaction in which the adduct of diene 113 and olefin 114 catalyzed its own formation. This was accomplished through binding of both reactants in a pre-organized fashion by means of multiple hydrogen bonding (see complex below structures 113 and 114 overleaf). 

Figure 22 Diels-Alder reaction of maleimide 28 with furan 26 gives rise to two diastereoisomeric products, exo- and endo-30, which are both capable of accelerating their own formation in an autocatalytic manner. The two cycloadducts do not have any measurable catalytic effect on the formation of their partner diastereoisomer. Maleimide 27 was used as a control compound to give products exo-and endo-29 that highlight the importance of hydrogen bonding since the iV-methyl anihde is incapable of binding the carboxylic acid recognition site in 26.

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