Enantio- and diastereo-selective synthesis of spirocyclic compounds

Abstract

Spirocyclic diones such as (R)-spiro[4.4]nonane-1,6-dione 1a, (R)-spiro[4.5]decane-1,6-dione 1b and (R)-spiro[5.5] undecane-1,7-dione 1c, and the corresponding cis,cis-diols 2a–c have been enantio- and diastereo-selectively synthesized by asymmetric alkylation and reduction using C₂-symmetric cycloalkane-1,2-diols as a chiral auxiliary.