work as organocatalysts for Mitsunobureactions because they provide ethyl 2-arylazocarboxylates through aerobic oxidation with a catalytic amount of iron phthalocyanine. First, ethyl 2-(3,4-dichlorophenyl)hydrazinecarboxylate has been identified as a potent catalyst, and the reactivity of the catalyticMitsunobureaction was improved through strict optimization of the reaction conditions. Investigation
palladium‐catalyzed asymmetric OHinsertionreaction was developed. Palladium complexes with chiral spiro bisoxazoline ligands promoted the insertion of α‐aryl‐α‐diazoacetates into the OH bond of phenols with high yield and excellent enantioselectivity under mild reaction conditions. This palladium‐catalyzed asymmetric OHinsertionreaction provided an efficient and highly enantioselective method for the preparation
Design and Evaluation of Inclusion Resolutions, Based on Readily Available Host Compounds
作者:Simona Müller、Marcel Cyrus Afraz、René de Gelder、Gerry J. A. Ariaans、Bernard Kaptein、Quirinus B. Broxterman、Alle Bruggink
DOI:10.1002/ejoc.200400613
日期:2005.3
of enantiomers through selective crystallisation of diastereomeric inclusioncompounds can extend the scope of traditional racemate resolution beyond salt forming compounds. To assess the practical value of this approach the literature was carefully screened and promising results were checked. Also an extensive range of new inclusion hosts suitable for resolution processes, derived from simple hydroxyand
Asymmetric O–H insertion reaction of carbenoids catalyzed by chiral bicyclo bisoxazoline copper(I) and (II) complexes
作者:Paul Le Maux、Daniel Carrié、Philippe Jéhan、Gérard Simonneaux
DOI:10.1016/j.tet.2016.06.044
日期:2016.8
Chiral copper(I) and (II)-bicyclobisoxazoline complexes were found to catalyze the insertion of α-diazocarbonyl compounds into O–H bonds of alcohols. The insertion reactions of various α-diazopropionates proceeded with moderate yields (40–90%) and high enantioselectivities (up to 92% and 94% with copper(I) and copper(II)-catalysts, respectively). A predominant effect on the enantiocontrol of the reaction
Planar Chiral [2.2]Paracyclophane-Based Bisoxazoline Ligands: Design, Synthesis, and Use in Cu-Catalyzed Inter- and Intramolecular Asymmetric O–H Insertion Reactions
作者:Shinji Kitagaki、Shunsuke Murata、Kisaki Asaoka、Kenta Sugisaka、Chisato Mukai、Naoko Takenaga、Keisuke Yoshida
DOI:10.1248/cpb.c18-00519
日期:2018.10.1
insertion reactions of α-diazo esters. The reactivities and enantioselectivities of Cu complexes of the synthesized bisoxazoline ligands were lower than those of ligands without central chirality. However, planar chiral [2.2]paracyclophane-based bisoxazoline ligands with an inserted benzene spacer that had a sterically demanding isopropyl substituent showed good enantioselectivities in inter- and intramolecular