1 research outputs found
Probing the Synergistic Catalytic Model: A Rationally Designed Urea-Tagged Proline Catalyst for the Direct Asymmetric Aldol Reaction
A urea
tag was incorporated at the C-4 position of proline, <i>cis</i> to its COOH group, in order to explore the prospect
of a synergistic effect between the two functional groups in the transition
state of the enamine route to the asymmetric aldol reaction. The catalyst
proved to be an excellent performer, delivering aldols in high yields
and with excellent enantio- and diastereoselectivities using just
2 mol % loading in the presence of water; it also exhibited good levels
of recyclability under aqueous conditions. The favorable results reveal
the interesting possibility of an intramolecular host–guest
interaction between the urea and the amino acid moieties, exerting
a beneficial effect on catalysis. The concept could certainly offer
a new direction toward more efficient catalyst design