137329-90-9Relevant academic research and scientific papers
ENANTIOSELECTIVE HYDROGENATION REACTIONS WITH A FULL SET OF PREFORMED AND PREPARED IN SITU CHIRAL DIPHOSPHINE-RUTHENIUM (II) CATALYSTS
Genet, J. P.,Pinel, C.,Ratovelomanana-Vidal, V.,Mallart, S.,Pfister, X.,et al.
, p. 675 - 690 (1994)
The new class of 2-methylallyl ruthenium chiral diphosphines 1 are efficient in asymmetric hydrogenation of α,β unsaturated acids and allylic alcohols.The related chiral halogen-containing ruthenium catalysts 2 are prepared from 1 or in situ from (COD)Ru(η3-(CH2)2CHCH3)2 by ligand exchange with the chelating diphosphine followed by protonation (HX) in acetone.This procedure allows rapid screening of chiral phosphines, such as Diop, Chiraphos, Cbd, Bppm, Binap, β-glucophos, Biphemp, MeO-Biphep, Me-Duphos, in ruthenium mediated hydrogenations of prochiral substrates.A high efficiency is displayed by Ru-catalysts having atropisomeric ligands (e.e. up to 99percent), and a C2 symmetric bis(phospholane) has also emerged as a valuable ligand (Me-Duphos, e.e. up to 87percent not optimized).Asymmetric hydrogenation of β-keto esters can be conducted under quite mild conditions (4 atm. of H2, 50 deg C, e.e. up to 99percent), β-keto esters having a disubstituted double bond are also hydrogenated chemoselectively to unsaturated chiral alcohols under controlled conditions with excellent optical purities.
Enantioselective ruthenium-mediated hydrogenation: Developments and applications
Ratovelomanana-Vidal, Virginie,Genet, Jean-Pierre
, p. 163 - 171 (2007/10/03)
A general preparation of chiral ruthenium(II) catalysts and the homogeneous enantioselective hydrogenation of prochiral olefins and keto groups are presented. Some applications to the synthesis of biologically active compounds are reported.
