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Pd-catalyzed γ-arylation of γ,δ-unsaturated O-carbamates via an unusual haptotropic rearrangement.

ABSTRACT: An unusual γ-selectivity was observed in the arylation of γ,δ-unsaturated O-carbamates involving directed lithiation, transmetallation to zinc and Negishi coupling, when a specific combination of aryl electrophile and phosphine ligand is employed. Mechanistic studies indicate that an unusual, stereospecific haptotropic rearrangement of the palladium-diene intermediate is involved.

SUBMITTER: Royal T

PROVIDER: S-EPMC6385668 | biostudies-other | 2019 Feb

REPOSITORIES: biostudies-other

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Pd-catalyzed γ-arylation of γ,δ-unsaturated O-carbamates via an unusual haptotropic rearrangement.

Royal Titouan T Baudoin Olivier O

Chemical science 20181226 8

An unusual γ-selectivity was observed in the arylation of γ,δ-unsaturated O-carbamates involving directed lithiation, transmetallation to zinc and Negishi coupling, when a specific combination of aryl electrophile and phosphine ligand is employed. Mechanistic studies indicate that an unusual, stereospecific haptotropic rearrangement of the palladium-diene intermediate is involved. ...[more]

PMID: 30881660

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