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Transition metal-free cross-coupling of furan ring with haloacetylenes.

ABSTRACT: On the example of menthofuran, a naturally abundant compound, it has been shown for the first time that the furan ring can be readily cross-coupled with acylhaloacetylenes in the solid Al2O3 powder at room temperature to afford the corresponding 2-ethynyl derivatives in up to 88% yield. The reaction represents a ring closing/ring opening process that includes reversible formation of the intermediate cycloadducts further producing acetylene derivatives with elimination of HHal.

SUBMITTER: Sobenina LN

PROVIDER: S-EPMC7127138 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Transition metal-free cross-coupling of furan ring with haloacetylenes.

Sobenina Lyubov N LN Tomilin Denis N DN Gotsko Maxim D MD Ushakov Igor A IA Trofimov Boris A BA

Tetrahedron 20180212 13

On the example of menthofuran, a naturally abundant compound, it has been shown for the first time that the furan ring can be readily cross-coupled with acylhaloacetylenes in the solid Al<sub>2</sub>O<sub>3</sub> powder at room temperature to afford the corresponding 2-ethynyl derivatives in up to 88% yield. The reaction represents a ring closing/ring opening process that includes reversible formation of the intermediate cycloadducts further producing acetylene derivatives with elimination of HH ...[more]

PMID: 32287432

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