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Borylation and rearrangement of alkynyloxiranes: a stereospecific route to substituted α-enynes.

ABSTRACT: 1,3-Enynes are important building blocks in organic synthesis and also constitute the key motif in various bioactive natural products and functional materials. However, synthetic approaches to stereodefined substituted 1,3-enynes remain a challenge, as they are limited to Wittig and cross-coupling reactions. Herein, stereodefined 1,3-enynes, including tetrasubstituted ones, were straightforwardly synthesized from cis or trans-alkynylated oxiranes in good to excellent yields by a one-pot cascade process. The procedure relies on oxirane deprotonation, borylation and a stereospecific rearrangement of the so-formed alkynyloxiranyl borates. This stereospecific process overall transfers the cis or trans-stereochemistry of the starting alkynyloxiranes to the resulting 1,3-enynes.

SUBMITTER: Fuentespina RP

PROVIDER: S-EPMC6604752 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Borylation and rearrangement of alkynyloxiranes: a stereospecific route to substituted α-enynes.

Fuentespina Ruben Pomar RP Garcia de la Cruz José Angel JA Durin Gabriel G Mamane Victor V Weibel Jean-Marc JM Pale Patrick P

Beilstein journal of organic chemistry 20190627

1,3-Enynes are important building blocks in organic synthesis and also constitute the key motif in various bioactive natural products and functional materials. However, synthetic approaches to stereodefined substituted 1,3-enynes remain a challenge, as they are limited to Wittig and cross-coupling reactions. Herein, stereodefined 1,3-enynes, including tetrasubstituted ones, were straightforwardly synthesized from cis or trans-alkynylated oxiranes in good to excellent yields by a on ...[more]

PMID: 31293691

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