950596-31-3Relevant academic research and scientific papers
A reusable TNF-tagged chiral bis(oxazoline)-copper catalyst for Diels- Alder transformations
Didier, Dorian,Schulz, Emmanuelle
, p. 1309 - 1314 (2012)
A chiral bis(oxazoline) ligand, substituted on the methylene bridge by a covalent link to an electron-deficient moiety (2,4,7-trinitrofluoren-9-one, TNF), is a useful ligand associated to copper(II) salts to promote enantioselective Diels-Alder reactions between N-acyloxazolidinones and cyclopentadiene. Owing to different solubility properties, the corresponding catalyst was precipitated by pentane addition after reaction completion and was easily recovered by filtration. It was successfully reused in up to 20 successive catalytic cycles for the formation of the targeted products with no loss of either the activity or the enantioselectivity along with the recycling. Georg Thieme Verlag Stuttgart · New York.
Copper-Catalyzed Enantioselective Arylation via Radical-Mediated C-C Bond Cleavage: Synthesis of Chiral ω,ω-Diaryl Alkyl Nitriles
Cui, Guo-Qing,Dai, Jing-Cheng,Li, Yan,Li, Yuan-Bo,Hu, Duo-Duo,Bian, Kang-Jie,Sheng, Jie,Wang, Xi-Sheng
supporting information, p. 7503 - 7507 (2021/10/02)
The first example of copper-catalyzed ring-opening, enantioselective arylation of cyclic ketoxime esters to access ω,ω-diaryl alkyl nitriles has been developed in high yield (up to 92% yield) with excellent enantioselectivity (up to 91% ee). Side-arm bis(oxazoline) ligand plays a significant role in this asymmetric catalytic transformation, which provides an efficient route to construct diverse chiral ω,ω-diaryl alkyl nitriles. Synthetic utility has also been demonstrated in the further derivatization of the ω,ω-diaryl alkyl nitrile to the corresponding amide.
Bifunctional photocatalysts for enantioselective aerobic oxidation of β-ketoesters
Ding, Wei,Lu, Liang-Qiu,Zhou, Quan-Quan,Wei, Yi,Chen, Jia-Rong,Xiao, Wen-Jing
supporting information, p. 63 - 66 (2017/05/16)
A novel visible-light-responsive chiral ligand has been developed by grafting a triplet state photosensitizer to chiral bisoxazoline ligands. Complexation of this ligand with Ni(acac)2 results in a powerful catalyst for the asymmetric oxidation reaction of β-ketoesters, which uses oxygen or air as the green oxidant and visible light or sunlight as the ideal driving force. Using this protocol, Products containing the α-hydroxy-β-dicarbonyl motif are produced in high yields and with excellent enantiopurities.
Using a tripod as a chiral chelating ligand: Chemical exchange between equivalent molecular structures in palladium catalysis with 1,1,1- tris(oxazolinyl)ethane ("trisox")
Foltz, Carole,Enders, Markus,Bellemin-Laponnaz, Stephane,Wadepohl, Hubert,Gade, Lutz H.
, p. 5994 - 6008 (2008/02/13)
Threefold symmetrical chiral podands may simplify the stereochemistry of key catalytic intermediates for cases in which they only act as bidentate ligands. This applies to systems in which chemical exchange between the different κ2-coordinated
