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Acyl(chloro)phosphines RC(O)P(Cl)( t -Bu) have been prepared by formal insertion of tert -butyl phosphinidene ( t -Bu–P) from t -BuP A ( A = C 14 H 10 or anthracene) into the C–Cl bond of acyl chlorides. We show that the under-explored acyl(chloro)phosphine functional group provides an efficient method to prepare bis(acyl)phosphines, which are important precursors to compounds used industrially as radical polymerization initiators. Experimental and computational investigations into the mechanism of formation of acyl(chloro)phosphines by our synthetic method reveal a pathway in which chloride attacks a phosphonium intermediate and leads to the reductive loss of anthracene from the phosphorus center in a P( v ) to P( iii ) process. The synthetic applicability of the acyl(chloro)phosphine functional group has been demonstrated by reduction to an acylphosphide anion, which can in turn be treated with an acyl chloride to furnish dissymmetric bis(acyl)phosphines.
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This content will become publicly available on July 25, 2026
A general leaving group assisted strategy for synthesis of pentafluorosulfanyl allylic compounds
Fluorine-containing allyl compounds are prevalent in drugs and bioactive molecules. Here, we report a straightforward and efficient radical pentafluorosulfanylation of allyl sulfones using sulfur chloride pentafluoride (SF5Cl) to synthesize structurally diverse pentafluorosulfanyl allylic compounds. This transformation exhibits excellent functional group tolerance and achieves an impressive isolated yield of up to 98% in just 1 minute under ultraviolet light. Mechanistic studies suggest that the sulfonyl group acts as a free radical leaving group, with the capability of abstracting the chlorine atom from SF5Cl. This radical chain propagation pathway facilitates the rapid regeneration of the sulfur pentafluoride radical, resulting in a notably high quantum yield. Moreover, this light-driven radical pentafluorosulfanylation simplifies the synthetic pathway to modify complex and bioactive molecules. In addition, the drug-modified pentafluorosulfanyl compounds exhibited promising effects in inhibiting cancer cell proliferation, both in vitro and in vivo. Therefore, this protocol provides a practical synthetic route to radical pentafluorosulfanylation, highlighting its potential in drug discovery.
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- Award ID(s):
- 1955284
- PAR ID:
- 10639284
- Publisher / Repository:
- AAAS
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 11
- Issue:
- 30
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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