Arabinose-derived ketones as catalysts for asymmetric epoxidation of alkenes.
[reaction: see text] Readily available arabinose-derived ketones, containing a tunable butane-2,3-diacetal as the steric blocker, displayed increasing enantioselectivity (up to 90% ee) with the size of the acetal alkyl group in catalytic asymmetric epoxidation of trans-disubstituted and trisubstituted alkenes. The stereochemical communication between our ketone catalysts and the alkene substrates is mainly due to steric effect, and electronic effect involving pi-pi interaction between phenyl groups of substrate and of catalyst did not appear to be operative in our system.
Shing
Tony K M
TK
Department of Chemistry, Chinese University of Hong Kong, Shatin, Hong Kong, China. tonyshing@cuhk.edu.hk
Leung
Gulice Y C
GY
Luk
To
T
D000475:Alkenes / Q000737:chemistry*; D001089:Arabinose / Q000737:chemistry*; D002384:Catalysis; D004852:Epoxy Compounds / Q000138:chemical synthesis*; D007659:Ketones / Q000737:chemistry*
D000475:Alkenes; D004852:Epoxy Compounds; D007659:Ketones; D001089:Arabinose