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Exploiting the radical reactivity of diazaphosphinanes in hydrodehalogenations and cascade cyclizations.

ABSTRACT: The remarkable reducibility of diazaphosphinanes has been extensively applied in various hydrogenations, based on and yet limited by their well-known hydridic reactivity. Here we exploited their unprecedented radical reactivity to implement hydrodehalogenations and cascade cyclizations originally inaccessible by hydride transfer. These reactions feature a broad substrate scope, high efficiency and simplicity of manipulation. Mechanistic studies suggested a radical chain process in which a phosphinyl radical is generated in a catalytic cycle via hydrogen-atom transfer from diazaphosphinanes. The radical reactivity of diazaphosphinanes disclosed here differs from their well-established hydridic reactivity, and hence, opens a new avenue for diazaphosphinane applications in organic syntheses.

SUBMITTER: Zhang J

PROVIDER: S-EPMC8159257 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Exploiting the radical reactivity of diazaphosphinanes in hydrodehalogenations and cascade cyclizations.

Zhang Jingjing J Yang Jin-Dong JD Cheng Jin-Pei JP

Chemical science 20200423 18

The remarkable reducibility of diazaphosphinanes has been extensively applied in various hydrogenations, based on and yet limited by their well-known hydridic reactivity. Here we exploited their unprecedented radical reactivity to implement hydrodehalogenations and cascade cyclizations originally inaccessible by hydride transfer. These reactions feature a broad substrate scope, high efficiency and simplicity of manipulation. Mechanistic studies suggested a radical chain process in which a phosph ...[more]

PMID: 34122935

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