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Dealkenylative Alkynylation Using Catalytic Fe^II and Vitamin C.

ABSTRACT: In this paper, we report the synthesis of alkyl-tethered alkynes through ozone-mediated and Fe^II-catalyzed dealkenylative alkynylation of unactivated alkenes in the presence of alkynyl sulfones. This one-pot reaction, which employs a combination of a catalytic Fe^II salt and l-ascorbic acid, proceeds under mild conditions with good efficiency, high stereoselectivity, and broad functional group compatibility. In contrast to our previous Fe^II-mediated reductive fragmentation of α-methoxyhydroperoxides, the Fe^II-catalyzed process was devised through a thorough kinetic analysis of the multiple competing radical (redox) pathways. We highlight the potential of this dealkenylative alkynylation through multiple post-synthetic transformations and late-stage diversifications of complex molecules, including natural products and pharmaceuticals.

SUBMITTER: Swain M

PROVIDER: S-EPMC9731399 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Dealkenylative Alkynylation Using Catalytic FeII and Vitamin C.

Swain Manisha M Bunnell Thomas B TB Kim Jacob J Kwon Ohyun O

Journal of the American Chemical Society 20220804 32

In this paper, we report the synthesis of alkyl-tethered alkynes through ozone-mediated and FeII-catalyzed dealkenylative alkynylation of unactivated alkenes in the presence of alkynyl sulfones. This one-pot reaction, which employs a combination of a catalytic FeII salt and l-ascorbic acid, proceeds under mild conditions with good efficiency, high stereoselectivity, and broad functional group compatibility. In contrast to our previous FeII-mediated reductive frag ...[more]

PMID: 35929075

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Dealkenylative Alkynylation Using Catalytic Fe^II and Vitamin C.

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Dealkenylative Alkynylation Using Catalytic Fe<sup>II</sup> and Vitamin C.

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