Synthesis of heterocyclic-fused benzopyrans <i>via</i> the Pd(<small>II</small>)-catalyzed C&#x2013;H alkenylation/C&#x2013;O cyclization of flavones and coumarins

다국어 초록 (Multilingual Abstract)

<P>An efficient and practical method for effecting a tandem C–H alkenylation/C–O cyclization has been achieved <I>via</I> the C–H functionalization of flavone derivatives. The synthetic utility of the one-pot sequence was demonstrated by obtaining convenient access to coumarin-annelated benzopyrans. The reaction scope for the transformation was found to be fairly broad, affording good yields of a wide range of flavone- or coumarin-fused benzopyran motifs, which are privileged structures in many biologically active compounds.</P>

<P>Graphic Abstract</P><P>An efficient and practical method for effecting a tandem C–H alkenylation/C–O cyclization has been achieved <I>via</I> the C–H functionalization of flavone derivatives.
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