Catalytic and highly enantioselective reactions of alpha-sulfonyl carbanions with chiral bis(oxazoline)s.
The enantioselective reactions of lithiated benzyl trifluoromethyl sulfones with a substoichiometric amount of a bis(oxazoline) and various aldehydes is disclosed. The products were formed with excellent diastereo- and enantioselectivities. Fluorination of the sulfone with N-fluorobenzenesulfonimide and a stoichiometric amount of a bis(oxazoline) gave products with extremely high enantioselectivities (up to 99% ee; ee=enantiomeric excess). The enantioselective reaction was confirmed to proceed through a dynamic thermodynamic resolution pathway.
Nakamura
Shuichi
S
Department of Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Gokiso, Nagoya 466-8555, Japan. snakamur@nitech.ac.jp
Hirata
Norimune
N
Yamada
Ryusuke
R
Kita
Takeshi
T
Shibata
Norio
N
Toru
Takeshi
T