jo9b03055_si_004.cif (27.35 kB)

Synthesis of 5‑Membered Sulfur Heterocycles via Tin-Catalyzed Annulation of Mercapto Ketones with Activated Alkenes

Download (27.35 kB)
posted on 06.01.2020, 12:03 by Itaru Suzuki, Yuki Sakamoto, Yuta Seo, Yoriko Ninomaru, Kodai Tokuda, Ikuya Shibata
Efficient conversion of α-mercapto ketones 1 with activated alkenes 2 into S-heterocycles was developed with Sn­(Oct)2–2MeOH acting as a catalyst. Two types of products, dihydrothiophene 3 and thiolane 4, were obtained. The selectivity of the products was dependent on the reaction temperature and on the rearrangement of the S-heterocycles from 3 to 4 under heating conditions. The dihydrothiophenes 3 were transformed into useful thiolactones 68 and thiophene 9.