- Stereoselective aldol-type cyclization reaction mediated by dibutylboron triflate/diisopropylethylamine.
Stereoselective aldol-type cyclization reaction mediated by dibutylboron triflate/diisopropylethylamine.
Organic letters (2004-01-03)
Sanjib Das, Lian-Sheng Li, Subhash C Sinha
PMID14703366
ZUSAMMENFASSUNG
[reaction: see text] Dibutylboron triflate/diisopropylethylamine mediated aldol-type cyclization provides an expedient route for the stereoselective synthesis of cyclic ethers in a single step. The method is highly efficient for the stereoselective synthesis of 4-cis-tetrahydropyranones. The reaction is proposed to proceed via an S(N)1-type mechanism through a chair-like transition state, in which both substituents occupy equatorial positions.