Titanium cis-1,2-diaminocyclohexane (cis-DACH) salalen catalysts for the asymmetric epoxidation of terminal non-conjugated olefins with hydrogen peroxide.
Chiral Ti salalen complexes catalyze the asymmetric epoxidation of terminal non-conjugated olefins with hydrogen peroxide. Modular ligands based on cis-1,2-diamino-cyclohexane (cis-DACH) were developed, giving high yields and enantiomeric excesses (ee, up to 96 %) at catalyst loadings as low as 0.1-0.5 mol %, and even under solvent-free conditions.
University of Cologne, Department of Chemistry, Organic Chemistry, Greinstrasse 4, 50939 Cologne (Germany), Fax: (+49) 221-470-5102.
Qifang
Q
Wang
Jörg-M
JM
Neudörfl
Albrecht
A
Berkessel
asymmetric synthesis; epoxidation; hydrogen peroxide; terminal olefins; titanium