Highly Selective Copper-Catalyzed Ring Expansion of Vinyl Thiiranes: Application to Synthesis of Biotin and the Heterocyclic Core of Plavix
摘要:
We report herein a new, highly selective, mild copper-catalyzed vinyl thiirane ring-expansion protocol for the formation of 2,5-dihydrothiophenes. Preliminary substrate scope and applications of this new synthetic disconnection to the formal racemic total synthesis of biotin and the synthesis of the antiplatelet blockbuster pharmaceutical agent Plavix are described.
Production of 2,5-Dihydrofurans and Analogous Compounds
申请人:Njardarson Jon
公开号:US20090131691A1
公开(公告)日:2009-05-21
Vinyl oxiranes are rearranged to 2,5-dihydrofuran using catalyst (III) or (IV). The 2,5-dihydrofuran can be reduced to tetrahydrofuran. 3,4-Epoxy-1-butene substrate is converted to 2,5-dihydrofuran which in turn is converted to tetrahydrofuran. Substrate for making 3-methyltetrahydrofuran is prepared from isoprene. Substrate for making 2-methyltetrahydrofuran is prepared from piperylene. Reactions analogous to that with vinyl oxiranes are carried out with vinyl thiiranes and vinyl aziridines.