1006591-46-3Relevant academic research and scientific papers
Scandium triflate and secondary amine promoted AA′B 2:1 coupling and formal inverse electron demand Diels-Alder reactions of dienals
Smith, Chris D.,Batey, Robert A.
, p. 652 - 663 (2008/09/16)
Reaction prospecting studies resulted in the discovery of a Sc(OTf)3 promoted novel AA′B 2:1 coupling of imidazolone or benzofuran substituted enals with morpholine. A related Sc(OTf)3/morpholine promoted reaction was demonstrated for the coupling of a benzofuran substituted enal with dihydrofuran. The formation of these adducts is consistent with formal inverse electron demand Diels-Alder cycloadditions, most likely in a stepwise manner via a domino Michael-Mannich annulation process, involving iminium ion activation of the diene. A purely amine promoted formal inverse electron demand Diels-Alder cycloaddition approach was also demonstrated in the 2:1 coupling of 2,4-hexadienal with methanol. These reactions demonstrate the concepts of dual metal/amine catalysis and amine promoted formal inverse electron demand Diels-Alder cycloadditions. They differ from known examples of organocatalyzed Diels-Alder reactions, in which iminium ion activation of the dienophiles or enamine activation of the dienes occur.
