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Synthesis of cyclic alkenylsiloxanes by semihydrogenation: a stereospecific route to (Z)-alkenyl polyenes.

ABSTRACT: Cyclic alkenylsiloxanes were synthesized by semihydrogenation of alkynylsilanes-a reaction previously plagued by poor stereoselectivity. The silanes, which can be synthesized on multigram scale, undergo Hiyama-Denmark coupling to give (Z)-alkenyl polyene motifs found in bioactive natural products. The ring size of the silane is crucial: five-membered cyclic siloxanes also couple under fluoride-free conditions, whilst their six-membered homologues do not, enabling orthogonality within this structural motif.

SUBMITTER: Elbert BL

PROVIDER: S-EPMC4531823 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Synthesis of cyclic alkenylsiloxanes by semihydrogenation: a stereospecific route to (Z)-alkenyl polyenes.

Elbert Bryony L BL Lim Diane S W DS Gudmundsson Haraldur G HG O'Hanlon Jack A JA Anderson Edward A EA

Chemistry (Weinheim an der Bergstrasse, Germany) 20140604 28

Cyclic alkenylsiloxanes were synthesized by semihydrogenation of alkynylsilanes-a reaction previously plagued by poor stereoselectivity. The silanes, which can be synthesized on multigram scale, undergo Hiyama-Denmark coupling to give (Z)-alkenyl polyene motifs found in bioactive natural products. The ring size of the silane is crucial: five-membered cyclic siloxanes also couple under fluoride-free conditions, whilst their six-membered homologues do not, enabling orthogonality within this struct ...[more]

PMID: 24899240

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