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Ylide-Functionalization via Metalated Ylides: Synthesis and Structural Properties.

ABSTRACT: The ?-metallated ylides [Ph₃P-C-Z]^-M⁺ (with Z=SO₂Tol or CN and M=Na or K) were used as versatile nucleophiles for the facile access to ylide-substituted compounds. Halogenations, alkylations, carbonylations and functionalization reactions with main group element halides were easily accomplished by simple trapping reactions with the appropriate electrophiles. X-ray crystallographic studies of all compounds - including the first structures of ?-fluorinated P-ylides - showed remarkable differences in the ylide backbone depending on the substituents. In the fluorinated compounds, a change from a fully planar to a pyramidalized ylidic carbon centre was observed despite the strongly anion-stabilizing ability of the yldiide substituent. ?-Donation from the ylide substituent also resulted in geometric restrictions depending on the steric and electronic properties of the introduced substituents.

SUBMITTER: Schwarz C

PROVIDER: S-EPMC6519319 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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