Synthesis and Diels-Alder Reactions of N-Methylthionomaleimide

Article abstract of DOI:10.1021/jo00040a046

N-Methylthionomaleimide (6) has been synthesized.It is the first example of a thionomaleimide unsubstituted on the olefinic C atoms.Its dienophilic behavior at the olefinic center, with representative dienes (symmetrical and unsymmetrical), has been investigated.There is appreciable regioselectivity with terminally oxygenated unsymmetrical dienes, the O-substituted carbon of the diene adding preferentially to the thiono-substituted end of the olefin.