Author/Authors :
Li، نويسنده , , Wenji and Thakur، نويسنده , , Santosh Singh and Chen، نويسنده , , Shu-Wei and Shin، نويسنده , , Chang-Kyo and Kawthekar، نويسنده , , Rahul B. and Kim، نويسنده , , Geon-Joong، نويسنده ,
Abstract :
The binuclear chiral (salen) Co complexes bearing Lewis acids of Al and Ga catalyze regio- and enantioselective ring opening of terminal epoxides with carboxylic acids. The ring opened product of epichlorohydrin with carboxylic acids followed by cyclization step in the presence of catalyst and base represent straightforward, efficient methods for the synthesis of enatiomerically enriched (>99% ee) valuable terminal epoxides. Strong synergistic effects of different Lewis acid of Co–Al and Co–Ga were exhibited in the catalytic process.
Keywords :
Asymmetric catalysis , Dinuclear chiral catalyst , cyclization , Asymmetric ring opening reactions