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Stereocontrolled regeneration of olefins from epoxides.

ABSTRACT: Through treatment with NaI and trifluoroacetic anhydride, which presumably forms trifluoroacetyl iodide in situ, epoxides can be converted to olefins. This reaction now has been shown to tolerate remote olefins without loss of their individual stereochemistry. A reaction sequence involving regiospecific epoxidation of an isoprenoid alcohol, conversion of the alcohol to an azide, and cycloaddition with an acetylene, followed by conversion of the epoxide back to the original olefin, has allowed stereocontrolled preparation of triazole bisphosphonates with a farnesyl or a geranylgeranyl substituent. This strategy may be applicable selective protection of an alkene in other polyolefins, including substrates for metathesis reactions.

SUBMITTER: Wills VS

PROVIDER: S-EPMC4778745 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Stereocontrolled regeneration of olefins from epoxides.

Wills Veronica S VS Zhou Xiang X Allen Cheryl C Holstein Sarah A SA Wiemer David F DF

Tetrahedron letters 20160301 12

Through treatment with NaI and trifluoroacetic anhydride, which presumably forms trifluoroacetyl iodide <i>in situ</i>, epoxides can be converted to olefins. This reaction now has been shown to tolerate remote olefins without loss of their individual stereochemistry. A reaction sequence involving regiospecific epoxidation of an isoprenoid alcohol, conversion of the alcohol to an azide, and cycloaddition with an acetylene, followed by conversion of the epoxide back to the original olefin, has all ...[more]

PMID: 26955189

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