Reference of (R)-Ethyl 4-chloro-3-hydroxybutanoate. The protonation of heteroatoms in aromatic heterocycles can be divided into two categories: lone pairs of electrons are in the aromatic ring conjugated system; and lone pairs of electrons do not participate. Compound: (R)-Ethyl 4-chloro-3-hydroxybutanoate, is researched, Molecular C6H11ClO3, CAS is 90866-33-4, about Enantioselective hydrogenation reactions with a full set of preformed and prepared in situ chiral diphosphine-ruthenium(II) catalysts. Author is Genet, J. P.; Pinel, C.; Ratovelomanana-Vidal, V.; Mallart, S.; Pfister, X.; Bischoff, L.; Cano De Andrade, M. C.; Darses, S.; Galopin, C..
The new class of 2-methylallyl ruthenium chiral diphosphines (P*P)RuII(2-methylallyl)2 (1, P*P = chiral diphosphine) are efficient in asym. hydrogenation of α,β unsaturated acids and allylic alcs. The related chiral halogen-containing ruthenium catalysts (P*P)RuIIX2 (X = halogen) 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 99%) and a C2 sym. bis(phospholane) has also emerged as a valuable ligand (Me-Duphos, e.e. up to 87% not optimized). Asym. hydrogenation of β-keto esters can be conducted under quite mild conditions (4 atm. of H2, 50°, e.e. up to 99%). β-Keto esters having a disubstituted double bond are also hydrogenated chemoselectively to unsaturated chiral alcs. under controlled conditions with excellent optical purities.
《Enantioselective hydrogenation reactions with a full set of preformed and prepared in situ chiral diphosphine-ruthenium(II) catalysts》 provides a strategy for the preparation of materials with excellent comprehensive properties, which is conducive to broaden the application field of this compound((R)-Ethyl 4-chloro-3-hydroxybutanoate)Reference of (R)-Ethyl 4-chloro-3-hydroxybutanoate.