779-54-4Relevant articles and documents
Isotope effects and the nature of stereo- and regioselectivity in hydroaminations of vinylarenes catalyzed by palladium(II)-diphosphine complexes
Vo, Loan K.,Singleton, Daniel A.
, p. 2469 - 2472 (2004)
(Equation Presented) The hydroamination of styrene with aniline catalyzed by phosphine-ligated palladium triflates exhibits a substantial 13C isotope effect at the benzylic carbon. This supports rate-determining nucleophilic attack of amine on a η3-phenethyl palladium complex. Deuterium exchange observations and predicted isotope effects based on DFT calculations support this mechanism. Selectivity in these reactions is determined by the facility of palladium displacement after reversible hydropalladation of the alkene.
Measurements of Heavy-Atom Isotope Effects Using 1H NMR Spectroscopy
Pabis, Anna,Kaminski, Rafal,Ciepielowski, Grzegorz,Jankowski, Stefan,Paneth, Piotr
, p. 8033 - 8035 (2011)
A novel method for measuring heavy-atom KIEs for magnetically active isotopes using 1H NMR is presented. It takes advantage of the resonance split of the protons coupled with the heavy atom in the 1H spectrum. The method is validated by the example of the 13C-KIE on the hydroamination of styrene with aniline, catalyzed by phosphine-ligated palladium triflates.
Cyclometalation of (2 R,5 R)-2,5-diphenylpyrrolidine and 2-phenyl-2-imidazoline ligands with half-sandwich iridium(III) and rhodium(III) complexes
Feghali, Elias,Barloy, Laurent,Issenhuth, Jean-Thomas,Karmazin-Brelot, Lydia,Bailly, Corinne,Pfeffer, Michel
, p. 6186 - 6194 (2013)
Cyclometalation of (2R,5R)-2,5-diphenylpyrrolidine (1) with [(η5-Cp)MCl2]2 using NaOAc in CH 2Cl2 at room temperature, followed by cationization with KPF6 in CH3CN, cleanly yield
Highly enantioselective transfer hydrogenation catalyzed by diasteromeric mixtures of axially chiral (aR,S)- and (aS,S)-Biscarbolines
Dong, Mengxian,Gao, Xinyue,Xiang, Ying,Li, Longfei,Li, Shengnan,Wang, Xuxin,Li, Zhenqiu,Zhu, Huajie
supporting information, (2021/02/05)
The mixtures of axially chiral (aR,S)- and (aS,S)-biscarboline alcohols were firstly used as catalysts in enantioselective 1,2- and 1,4-transfer hydrogenations of ketimines and β-enamino esters, respectively. This mixed axially chiral catalysts exhibited
Chiral N-heterocyclic carbene-iridium complexes for asymmetric reduction of prochiral ketimines
Kathuria, Lakshay,Samuelson, Ashoka G.
, (2020/12/28)
Enantioselective reduction of imines to the corresponding chiral secondary amines has been studied using a series of chiral half-sandwich iridium complexes. Chiral N-heterocyclic carbene (NHC) ligands in these complexes were synthesized from readily available, naturally occurring amino acids. Inexpensive phenylsilane was used as a convenient hydrogen donor. Under the optimized conditions, Ir-NHC complexes could reduce ketimines in good yields, albeit with moderate enantiomeric excess (ee). The phenylglycine derived chiral NHC was shown to give the best Ir catalyst and it also gave the maximum ee compared to catalysts prepared from other NHCs in this series. The opposite enantiomer of the reduction product was always obtained while using the Ir complex bearing a valine based NHC. The yields were consistently high with a variety of imine substrates having different steric and electronic demands.