Electrostatically Enhanced Phosphoric Acids and Their Applications in Asymmetric Friedel–Crafts Alkylations
作者:Jie Ma、Steven R. Kass
DOI:10.1021/acs.joc.9b01741
日期:2019.9.6
series of electrostatically enhanced phosphoric acid catalysts were synthesized and studied. These compounds possess two positively charged N-octylpyridinium or triarylphosphonium ion centers at the 3,3′-positions of the (R)-BINOL backbone to enhance reactivity and provide needed steric bulk for enantioselective transformations. Catalytic activities for Friedel–Crafts alkylations of indoles with trans-β-nitrostyrenes
Immobilization of Diphenylamine-Linked Bis(oxazoline) Ligands and Their Application in the Asymmetric Friedel-Crafts Alkylation of Indole Derivatives with Nitroalkenes
作者:Han Liu、Da-Ming Du
DOI:10.1002/ejoc.200901434
日期:2010.4
A diphenylamine-linkedbis(oxazoline) ligand with trans-diphenyl substitution on the oxazoline rings has been immobilized onto one- to three-generation Frechet-type dendrimers and a C 3 -symmetric core structure. The catalytic activities and enantioselectivities of these new ligands were tested in the asymmetricFriedel-Craftsalkylation reactions of indolederivatives with nitroalkenes. The two types
Synthesis of chiral benzene-based tetraoxazolines and their application in asymmetric Friedel–Crafts alkylation of indole derivatives with nitroalkenes
作者:Wei-Jie Li
DOI:10.1016/j.catcom.2014.04.013
日期:2014.7
A series of new chiral benzene-based tetraoxazoline ligands were prepared in good yields through the reaction of 1,2,4,5-benzenetetracarboxylic acid and chiral β-amino alcohols by continuous removal of water, and the asymmetric Friedel–Craftsalkylation of indole derivatives with nitroalkenes was tested using the chiral catalysts, which were generated in situ by refluxing the above ligands and anhydrous
A New Type of Bis(sulfonamide)-Diamine Ligand for a Cu(OTf)<sub>2</sub>-Catalyzed Asymmetric Friedel–Crafts Alkylation Reaction of Indoles with Nitroalkenes
作者:Jing Wu、Xincheng Li、Fan Wu、Boshun Wan
DOI:10.1021/ol201914r
日期:2011.9.16
Chiral bis(sulfonamide)-diamine served as new type of ligand for a Cu(OTf)2-catalyzed asymmetricFriedel–Craftsalkylation reaction of indoles with nitroalkenes. The desired products were obtained with up to 99% yield and 97% ee.