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Understanding Site Selectivity in the Palladium-Catalyzed Cross-Coupling of Allenylsilanolates.

ABSTRACT: Allenylsilanolates can undergo cross-coupling at the ?- or ?-terminus, and site selectivity appears to be determined by the intrinsic transmetalation mechanism. Fine-tuning of concentration, nucleophilicity, and steric bulk of the silanolate moiety allows for the selective formation of one isomer over the other. Whereas the ?-isomer can be obtained in synthetically useful yield, the ?-isomer is favored only when employing reaction conditions that are inevitably associated with diminished reactivity.

SUBMITTER: Denmark SE

PROVIDER: S-EPMC5997285 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Understanding Site Selectivity in the Palladium-Catalyzed Cross-Coupling of Allenylsilanolates.

Denmark Scott E SE Ambrosi Andrea A

Synlett : accounts and rapid communications in synthetic organic chemistry 20170712 18

Allenylsilanolates can undergo cross-coupling at the α- or γ-terminus, and site selectivity appears to be determined by the intrinsic transmetalation mechanism. Fine-tuning of concentration, nucleophilicity, and steric bulk of the silanolate moiety allows for the selective formation of one isomer over the other. Whereas the α-isomer can be obtained in synthetically useful yield, the γ-isomer is favored only when employing reaction conditions that are inevitably associated with diminished reactiv ...[more]

PMID: 29904234

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