Double cationic propargylation: from linear to polycyclic ethers.
[reaction: see text]. The trapping of cations generated from Co2(CO)6-bispropargylic alcohols provided diethers in good yield. The procedure is also valid when two vicinal acetylenes are present. The methodology can be applied to the synthesis of symmetrical or unsymmetrical linear or cyclic propargylic ethers. The use of substrates with a stereochemically defined secondary nucleophilic alcohol provided cyclic ethers with a high degree of stereocontrol.
Díaz
D
D
Instituto Universitario de Bio-Orgánica Antonio González, Universidad de La Laguna, C/Astrofísico Francisco Sánchez, 2, 38206 La Laguna, Tenerife, Spain.
Martín
T
T
Martín
V S
VS