Metal-catalyzed cascade rearrangements of 3-alkynyl flavone ethers.

Metal-catalyzed cascade rearrangements of 3-alkynyl flavone ethers.

Organic letters (2013-04-12)

Yuan Xiong, Scott E Schaus, John A Porco

ABSTRACT

Metal-mediated rearrangements of 3-alkynyl flavone ethers are reported. The overall process involves 5-endo enyne cyclization to a platinum-containing spiro-oxocarbenium intermediate which may be trapped with methanol to produce spirodihydrofurans or further rearranged to afford either allenyl chromanediones or benzofuranones.

MATERIALS

Product Number

Brand

Product Description

357375

Sigma-Aldrich

Platinum, wire, diam. 0.076 mm, ≥99.99% trace metals basis

444685

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