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DOI: 10.1055/sos-SD-104-00395

Delvos, L. B.; Oestreich, M.Science of Synthesis Knowledge Updates, (20171142.

A recent report demonstrated that ynoates 208 react with silylboronic ester 19 in the presence of tributylphosphine as organocatalyst in a fundamentally different silaboration reaction to form trans-difunctionalized enoates 209 as single stereoisomers (Scheme 85).[‌114‌] Here, the Si—C bond formation occurs exclusively α to the carboxy group, and the boronic ester subunit is attached to the β-position of the triple bond. A variety of functionalized aryl and alkyl substituents at the β-carbon atom are tolerated, demonstrating broad functional-group tolerance. The target compounds are formed in good to excellent yields from equimolar amounts of acceptor and silicon pronucleophile.

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