Gold-catalyzed cycloisomerization of alk-4-yn-1-ones.
نویسندگان
چکیده
Depending on the substitution pattern and the solvent, the gold-catalyzed cyclization of alk-4-yn-1-ones affords different oxygen heterocycles under mild reaction conditions. Alkynones with one substituent at C-3 undergo a 5-exo-dig cycloisomerization to substituted furans , whereas a 6-endo-dig cyclization to 4H-pyrans is observed with substrates bearing two substituents at C-3. In alcoholic solvents, alkylidene/benzylidene-substituted tetrahydrofuranyl ethers are formed in a tandem nucleophilic addition/cycloisomerization.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 7 6 شماره
صفحات -
تاریخ انتشار 2009