Flex control: Malonate and tert‐butoxycarbonyl (Boc)‐protected imines react in the presence of the flexible catalyst 1 to furnish the S or the R adduct depending upon the solvent used. Kinetic analyses in this enantiodivergent organocatalysis show that enthalpy–entropy compensation explains this behavior.
Magnesium(II)-Binaphtholate as a Practical Chiral Catalyst for the Enantioselective Direct Mannich-Type Reaction with Malonates
作者:Manabu Hatano、Takahiro Horibe、Kazuaki Ishihara
DOI:10.1021/ol101353r
日期:2010.8.6
A highly enantioselective direct Mannich-typereaction of aldimines with dialkyl malonates was developed with the use of a Mg(II)-BINOLate salt, which was designed as a cooperative acid—base catalyst that can activate both aldimines and malonates. Optically active β-aminoesters and α-halo-β-aminoesters could be synthesized in high yields and with high enantioselectivities. This inexpensive and practical