Transition-metal-catalyzed asymmetric organic synthesis via polymer-attached optically active phosphine ligands. 13, Asymmetric hydrogenation with polymer catalysts containing primary and chiral secondary pendant alcohols
Author(s)
Stille, John K.
Date issued
1985
In
J. Org. Chem.
Vol
13
No
50
From page
2299
To page
302
Subjects
asym hydrogenation rhodium polymer catalyst phosphine copolymer rhodium catalyst hydrogenation acyl amino acid asym synthesis olefin asym hydrogenation rhodium polymer catalyst stereochem hydrogenation olefin rhodium polymer catalyst
Abstract
The copolymn. of styryl DIOP deriv. I and crosslinking monomer ethylene dimethacrylate with methacrylates (R)-CH2:CMeCO2CH2CH(OH)CH2OH [(R)-II], (S)-II, or (RS)-II gave the resp. copolymers, which were complexed with Rh via a Rh exchange with chloro(1,5-cyclooctadiene)rhodium(I) dimer. The resulting polymers contg. chiral Rh centers and the ancillary alc. sites catalyzed the hydrogenation of olefins III (R = H, Ph, R1 = NHAc; R = H, R1 = Ph) in EtOH to give chiral RCH2CHR1CO2H (IV). The catalyst prepd. from (R)-II gave IV (R = H, R1 = NHAc) in an optical yield that was 6% higher than that obtained from the polymer prepd. from (RS)-II and 8% higher than that obtained from the catalyst prepd. from (S)-II when the reactions were performed in THF. [on SciFinder(R)]
Publication type
journal article