202604-00-0Relevant academic research and scientific papers
A new procedure for highly stereoselective and regioselective synthesis of 2-ethynyl-3-hydroxytetrahydropyran derivatives based on alkyne-Co2(CO)6 complex
Mukai, Chisato,Sugimoto, Yu-Ichi,Ikeda, Yoshitaka,Hanaoka, Miyoji
, p. 823 - 850 (1998)
Treatment of trans-epoxides 3 with Co2(CO)8 gave the corresponding cobalt complexes, which were subsequently exposed to a catalytic amount of BF3·OEt2 at -78°C to provide exclusively cis-2-ethynyl-3- hydroxytetrahydropyran derivatives via endo mode cyclization pathway. cis- Congeners, cis-3 afforded the corresponding trans tetrahydropyran derivatives exclusively. This novel cyclization has been found to proceed with retention of configuration at the propynyl stereogenic center. Requirement for stereoselectivity in cyclization was discussed.
