The first addition of silyl enol ethers to internal unactivated alkynes

✍ Scribed by Ken-ichiro Imamura; Eiji Yoshikawa; Vladimir Gevorgyan; Yoshinori Yamamoto

• Publisher: Elsevier Science
• Year: 1999
• Tongue: French
• Weight: 227 KB
• Volume: 40
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(99)00654-1

✦ Synopsis

The EtAICl2-mediated intramolecular addition of silyl enol ethers to both terminal and internal unactivated alkyttes, bearing alkyl and phenyl susbstituents at the alkyne moiety, proceeded exclusively in the endo-fashion to give mono-and bicyclic p,T-unsaturated ketones in good to excellent yields. The mechanism of this regiospecific Lewis acid-assisted carbocyclization is proposed.