Stereoselective construction of cis-2,6-disubstituted tetrahydropyrans via an intramolecular bismuth-mediated oxa-conjugate addition reaction
نویسندگان
چکیده
منابع مشابه
Diastereoselective construction of anti-4,5-disubstituted-1,3-dioxolanes via a bismuth-mediated two-component hemiacetal oxa-conjugate addition of γ-hydroxy-α,β-unsaturated ketones with paraformaldehyde.
The bismuth-mediated two-component hemiacetal oxa-conjugate addition of γ-hydroxy-α,β-unsaturated ketones with paraformaldehyde affords anti-4,5-disubstituted-1,3-dioxolanes in an efficient and stereoselective manner. The reaction provides a practical, inexpensive and atom-economical approach to these types of heterocycles, which represent useful intermediates for target-directed synthesis and ...
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ژورنال
عنوان ژورنال: Tetrahedron Letters
سال: 2005
ISSN: 0040-4039
DOI: 10.1016/j.tetlet.2005.06.100