Synthetic methods of selenium- and tellurium variants of tetrathiafulvalene electron donors

Two very useful, versatile reactions applicable to the synthesis of TTF-type electron donors are presented: the one-pot preparation of 1,3-dichalcogenole-2-chalcogenones from readily available terminal alkynes and the ready formation of heterocyclic rings fused on TTF by transalkylation on a chalcogen atom. These reactions in combination with a conventional trialkyl phosphite-promoted coupling reaction of 1,3-dichalcogenole-2-chalcogenones provide a ready access to novel selenium- and tellurium- variants of TTF-type electron donors. A variety of synthetic examples of these compounds, especially inaccessible ones of six-membered heterocycle-fused type, five-membered heterocycle-fused type, dimeric type, and cyclophane type, are demonstrated.