An enantioselectiveBiginellireaction that proceeds by a dual-activation route has been developed by using a combined catalyst of a readily available trans-4-hydroxyproline-derived secondary amine and a Bronsted acid. Aromatic, heteroaromatic, and fused-ring aldehydes were found to be suitable substrates for this multicomponent reaction. The corresponding dihydropyrimidines were obtained in moderate-to-good
studies on this route for forming pincercomplexes revealed the intermediacy of [4-tert-butyl-2,6-bis(N-alkylimino)phenyl]chlorobis(triphenylphosphine)palladium which is in equilibrium with the corresponding NCN pincercomplexes via coordination/dissociation of the intramolecular imino groups and triphenylphosphine ligands. A series of chiral NCN pincercomplexes bearing pyrroloimidazolone units as
[EN] STEREOSELECTIVE SYNTHESIS OF ENANTIOMERICALLY-ENRICHED PANTOLACTONE<br/>[FR] SYNTHÈSE STÉRÉOSÉLECTIVE DE PANTOLACTONE ENRICHIE EN ÉNANTIOMÈRES
申请人:DSM IP ASSETS BV
公开号:WO2019228874A1
公开(公告)日:2019-12-05
The present invention relates stereoselective synthesis of enantiomerically enriched pantolactone.
本发明涉及对对映体富集的泛醇内酯进行立体选择性合成。
The Mimic of Type II Aldolases Chemistry: Asymmetric Synthesis of β-Hydroxy Ketones by Direct Aldol Reaction
作者:Zhijin Lu、Haibo Mei、Jianlin Han、Yi Pan
DOI:10.1111/j.1747-0285.2010.00998.x
日期:——
An efficient directaldolreaction has been developed for the synthesis of chiral β‐hydroxy ketone using a combination of C1‐symmetric chiral prolinamides based on o‐phenylenediamine and zinc triflate as catalyst. The reaction was convenient to carry out in aqueous media with up to 98% chemical yields and up to 94% ee values. The current strategy can be regarded as the analogue of aldolase type II
chiral tridentate bis(pyrroloimidazolone)pyridine (PyBPI) ligands have been designed, synthesized, and applied in an asymmetric Michael addition. With a 0.05 mol % PyBPI–Co(II) complex, β,γ-unsaturated α-keto esters reacted with 4-hydroxycoumarin to give the adducts in 93–99% yields and 90–97% ee. Experiments and DFT calculations supported the dual activation manner, in which the tridentateligand coordinated