Iron Corrole-catalyzed [4+2] Cycloaddition of Dienes and Aldehydes

We have developed cationic iron(IV) corrole-catalyzed formal hetero-Diels-Alder reaction of aldehydes with dienes, which opens the way for divergent synthesis of pyrans. The potential utility of the catalyst was also demonstrated by carrying out cycloaddition of alpha,beta-unsaturated aldehyde with a diene to give pyran selectively. Furthermore, the catalytic reactivity of iron corrole complex on the cycloaddition was determined by comparing that of iron porphyrin complex.