Diastereodivergent Addition of Allenylzincs to Aryl Glyoxylates
摘要:
A diastereodivergent addition of allenylzincs to aryl glyoxylates was observed depending on the method used for the preparation of the allenylzinc reagent. The allenylzincs were prepared from propargylic benzoates in the presence of a palladium catalyst or by metalation of alkynes.
Synthesis of Furo[2,3-<i>b</i>]pyran-2-ones through Ag(I)- or Ag(I)–Au(I)-Catalyzed Cascade Annulation of Alkynols and α-Ketoesters
作者:Sagar S. Thorat、Priyanka Kataria、Ravindar Kontham
DOI:10.1021/acs.orglett.7b04027
日期:2018.2.2
Ag(I)- or Ag(I)–Au(I)-catalyzed cascade annulation of alkynols (5-hexyn-1-ol systems) with α-ketoesters involving a dual activation process (π and σ) has been developed for the first time. This reaction proceeds through cycloisomerization of alkynol to give the 6-endo-enol ether followed by annulation with an α-ketoester to furnish furo[2,3-b]pyran-2-ones in good yields. Chemical structures of all
已经开发了Ag(I)-或Ag(I)-Au(I)催化的炔烃(5-己炔-1-醇系统)与α-酮酸酯的级联环化反应,涉及双活化过程(π和σ)。第一次。该反应通过炔醇的环异构化进行,得到6-内-烯醇醚,然后用α-酮酸酯环化,以良好的产率提供呋喃[2,3 - b ]吡喃-2-酮。所有产品的化学结构均通过单晶X射线分析和类似物严格确认。