One-pot synthesis of enantiopure syn-1,3-diacetates from racemic syn/anti mixtures of 1,3-diols by dynamic kinetic asymmetric transformation.
A one-pot synthesis of enantiomerically pure syn-1,3-diacetates starting from readily accessible racemic diastereomeric mixtures of 1,3-diols has been realized by combining (i) enzymatic transesterification, (ii) ruthenium-catalyzed epimerization of a secondary alcohol in a diol or diol monoacetate, and (iii) intramolecular acyl migration in a syn-1,3-diol monoacetate. The in situ coupling of these three processes results in an efficient enantioselective synthesis of acyclic syn-1,3-diacetates via combined deracemization-deepimerization and constitutes a dynamic kinetic asymmetric transformation concept. Several differently substituted unsymmetrical, acyclic syn-1,3-diacetates were obtained in yields up to 73% with excellent enantioselectivities (>99%) and good diastereomeric ratios (>90% syn).
Edin
Michaela
M
Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
Steinreiber
Johannes
J
Bäckvall
Jan-E
JE