チオンおよびセロンを用いた複素環化合物の合成

抄録

Benzothietes and benzoselenates were synthesized by the reaction of benzyne with thiones or selones. The reaction of di-tert-butyl selenoketone with propiolic acid gave 2H, 6H-1, 3-oxaselenin-6-one, whereas the reaction of di-tert-butyl thioketone with propiolic acid resulted in the recovery of the starting thioketone almost quantitatively. Other isolable thiones reacted with propiolic acid to give thiodioxenones in good yields. Thionation of thiones at room temperature afforded 1, 2, 4-trithiolanes via thiosulfine intermediates. Thionation of di-tert-butyl-thioketene S-oxide afforded 3, 3-di-tert-butyl-thiirane-2-thione (α-dithiolactone), which is the first example of an isolable α-dithiolactone. Sterically congested cis- and trans-1, 3, 4-selenadiazolines were isolated by one-pot reaction of ketone hydrazones with diselenium dibromide, which suggested the in situformation of selenoketone and diazoalkane intermediates. The reaction of acetophenone hydrazones with diselenium dibromide afforded 2, 5-diarylselenophenes in moderate yields.