Alkyne hydroamination is an effective approach for the production of enamines and enamine-containing
N-heterocycles. However, stereoselectivity control is a considerable challenge in this reaction because of the electronic repulsion between an incoming nitrogen lone pair and the alkyne π-system. Herein, we propose a methodology involving β-regio- and
Z-selective alkyne hydroamination by using tetrafluoro-λ
6-sulfanyl (SF
4) alkynes under superbasic, naked anion conditions. The reaction is compatible with a wide variety of
N-heterocycles, including indoles, carbazoles, pyrazoles, and imidazoles, and selectively furnishes SF
4-linked
Z-vinyl enamines with β-regioselectively. Moreover, the method can be extended to the β- and
Z-controlled, base-mediated alkyne hydrophenoxylation with phenols to provide SF
4-linked
Z-vinyl ethers in high yields. As the SF
4 unit has attracted attention as a bioisostere for alkynes,
p-benzenes, bicyclo[1.1.1]pentyl (BCP) groups, and cubanes in medicinal chemistry, this chemistry represents an effective approach to creating novel drug candidates incorporating SF
4-containing molecules.
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