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Synlett 2017; 28(18): 2415-2420
DOI: 10.1055/s-0036-1588471
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© Georg Thieme Verlag Stuttgart · New York

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

Scott E. Denmark  *
University of Illinois at Urbana-Champaign, Department of Chemistry, 600 S Mathews Ave., Urbana, IL 61801, USA   Email: sdenmark@illinois.edu
,
Andrea Ambrosi
› Author AffiliationsWe are grateful to the National Science Foundation (NSF CHE-1151566) for generous financial support. A.A. thanks the University of Illinois and Eli Lilly and Co. for graduate fellowships
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Publication History

Received: 18 April 2017

Accepted after revision: 22 May 2017

Publication Date:
12 July 2017 (online)

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Published as part of the Cluster Silicon in Synthesis and Catalysis

Abstract

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 reactivity.

Key words

allenes - cross-coupling - organosilanes - palladium - site selectivity - transmetalation

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/s-0036-1588471.
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  • References and Notes

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