Siloxane-based cross-coupling of bromopyridine derivatives: studies for the synthesis of streptonigrin and lavendamycin.

Org Lett

Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.

Published: December 2003

Highly functionalized 4-bromopyridines were prepared and found to undergo fluoride-promoted, Pd-catalyzed cross-coupling with aryltrialkoxysilanes to give sterically demanding biaryls. The 3-nitro-4-bromopyridine derivative coupled in good yield with TBAT (tetrabutylammonium triphenyldifluorosilicate) to provide a biaryl adduct that serves as a model system for the total synthesis of the antitumor antibiotics streptonigrin and lavendamycin. [reaction: see text]

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http://dx.doi.org/10.1021/ol0357503DOI Listing

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