Wills VS, Zhou X, Allen C, Holstein SA, Wiemer DF. Stereocontrolled regeneration of olefins from epoxides.
Tetrahedron Lett 2016;
57:1335-1337. [PMID:
26955189 PMCID:
PMC4778745 DOI:
10.1016/j.tetlet.2016.02.041]
[Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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.
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