1040908-34-6Relevant articles and documents
Reversible modulation of the activity of thiourea catalysts with anions: A simple approach to switchable asymmetric catalysis
Foli, Giacomo,D'Elia, Cecilia Sasso,Fochi, Mariafrancesca,Bernardi, Luca
, p. 66490 - 66494 (2016)
Leveraging the anion binding properties of thioureas, we show that the activity of known well-performing chiral catalysts can be reduced by coordinating anions (e.g. chloride) and restored by anion metatheses. Three benchmark enantioselective transformati
Exploiting the chiral ligands of bis(Imidazolinyl)-and bis(oxazolinyl)thiophenes—Synthesis and application in Cu-catalyzed friedel–crafts asymmetric alkylation
Al-Majid, Abdullah Mohammed,Alammari, Abdullah Saleh,Alshahrani, Saeed,Barakat, Assem,Haukka, Matti,Islam, Mohammad Shahidul
, (2021/12/17)
Five new C2-symmetric chiral ligands of 2,5-bis(imidazolinyl)thiophene (L1–L3) and 2,5-bis(oxazolinyl)thiophene (L4 and L5) were synthesized from thiophene-2,5-dicarboxylic acid (1) with enantiopure amino alcohols (4a–c) in excellent optical purity and chemical yield. The util-ity of these new chiral ligands for Friedel–Crafts asymmetric alkylation was explored. Subse-quently, the optimized tridentate ligand L5 and Cu(OTf)2 catalyst (15 mol%) in toluene for 48 h promoted Friedel–Crafts asymmetric alkylation in moderate to good yields (up to 76%) and with good enantioselectivity (up to 81% ee). The bis(oxazolinyl)thiophene ligands were more potent than bis(imidazolinyl)thiophene analogues for the asymmetric induction of the Friedel–Crafts asymmetric alkylation.
Rhodium-catalyzed asymmetric addition of arylboronic acids to indolylnitroalkenes
Xing, Junwei,Chen, Guihua,Cao, Peng,Liao, Jian
, p. 1230 - 1236 (2012/04/10)
Indolylnitroethanes and their derivatives are key intermediates to many bioactive structures. Most approaches to access chiral indolylnitroethanes involve organocatalyzed or metal-catalyzed asymmetric Friedel-Crafts reaction of indoles with nitroalkenes.
Chiral phosphoric acid catalyzed enantioselective Friedel-Crafts alkylation of indoles with nitroalkenes: Cooperative effect of 3 A molecular sieves
Itoh, Junji,Fuchibe, Kohei,Akiyama, Takahiko
supporting information; experimental part, p. 4016 - 4018 (2009/02/08)
(Chemical Equation Presented) Crafty catalysts: Friedel-Crafts alkylation of indoles with nitroalkenes proceeded in the presence of phosphoric acid 1 and 3 A molecular sieves to give Friedel-Crafts adducts with excellent enantioselectivities (see scheme).