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The Phospha-Bora-Wittig Reaction.

ABSTRACT: We report the phospha-bora-Wittig reaction for the direct preparation of phosphaalkenes from aldehydes, ketones, esters, or amides. The transient phosphaborene Mes*P═B-NR₂ reacts with carbonyl compounds to form 1,2,3-phosphaboraoxetanes, analogues of oxaphosphetane intermediates in the classical Wittig reaction. 1,2,3-Phosphaboraoxetanes undergo thermal or Lewis acid-promoted cycloreversion, yielding phosphaalkenes. Experimental and density functional theory studies reveal far-reaching similarities between classical and phospha-bora-Wittig reactions.

SUBMITTER: Borys AM

PROVIDER: S-EPMC8431359 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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The Phospha-Bora-Wittig Reaction.

Borys Andryj M AM Rice Ella F EF Nichol Gary S GS Cowley Michael J MJ

Journal of the American Chemical Society 20210826 35

We report the phospha-bora-Wittig reaction for the direct preparation of phosphaalkenes from aldehydes, ketones, esters, or amides. The transient phosphaborene Mes*P═B-NR<sub>2</sub> reacts with carbonyl compounds to form 1,2,3-phosphaboraoxetanes, analogues of oxaphosphetane intermediates in the classical Wittig reaction. 1,2,3-Phosphaboraoxetanes undergo thermal or Lewis acid-promoted cycloreversion, yielding phosphaalkenes. Experimental and density functional theory studies reveal far-reachin ...[more]

PMID: 34437805

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