Polystyrene-supported (R)-2-piperazino-1,1,2-triphenylethanol: a readily available supported ligand with unparalleled catalytic activity and enantioselectivity.
A very active and highly enantioselective catalytic resin, designed for minimal perturbation of the catalytic center by the polymer matrix, has been assembled in two steps from (S)-triphenylethylene oxide, piperazine, and Merrifield resin and tested in the enantioselective ethylation of aldehydes. 1-Arylpropanols of 94-95% ee are obtained in high yield by the use of only 2 mol % of catalytic resin at 0 degrees C for 4 h.
Castellnou
David
D
Institute of Chemical Research of Catalonia (ICIQ), 43007 Tarragona, Spain.
Solà
Lluís
L
Jimeno
Ciril
C
Fraile
José M
JM
Mayoral
José A
JA
Riera
Antoni
A
Pericàs
Miquel A
MA