A. Skowronska et al., THE DIELS-ALDER REACTIONS OF (Z)-1,2-DIHETEROSUBSTITUTED-1,3-DIENES -SULFUR AS A REGIOCHEMICAL CONTROL, Tetrahedron letters, 36(44), 1995, pp. 8133-8136
Thermal and Lewis acid catalysed cycloadditions of dienes 1 to dienoph
iles proceed with complete regio- and stereo-selectivity and provide a
route to the cyclic enones.