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Stereoselective Synthesis of Substituted Oxocene Cores by Lewis Acid Promoted Cyclization.

ABSTRACT: Substituted oxocene derivatives have been synthesized by Lewis acid catalyzed reactions of ?-hydroxyalkene and substituted aromatic aldehydes. The Cu(OTf)2-bis-phosphine catalyzed reaction typically provides substituted dihydropyran derivatives through an olefin migration followed by a Prins cyclization. The corresponding reaction catalyzed by TMSOTf or BF3·OEt2 provided eight-membered cyclic ethers (oxocenes), selectively. This methodology provides convenient access to a variety of 2,4,8-trisubstituted oxocenes in good yields and excellent diastereoselectivities.

SUBMITTER: Ghosh AK

PROVIDER: S-EPMC5317094 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Stereoselective Synthesis of Substituted Oxocene Cores by Lewis Acid Promoted Cyclization.

Ghosh Arun K AK Tomaine Anthony J AJ Cantwell Kelsey E KE

Organic letters 20160127 3

Substituted oxocene derivatives have been synthesized by Lewis acid catalyzed reactions of ε-hydroxyalkene and substituted aromatic aldehydes. The Cu(OTf)2-bis-phosphine catalyzed reaction typically provides substituted dihydropyran derivatives through an olefin migration followed by a Prins cyclization. The corresponding reaction catalyzed by TMSOTf or BF3·OEt2 provided eight-membered cyclic ethers (oxocenes), selectively. This methodology provides convenient access to a variety of 2,4,8-trisub ...[more]

PMID: 26829580

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