779-54-4Relevant academic research and scientific papers
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.
Double [3 + 2]-dimerisation cascade synthesis of bis(triazolyl)bisphosphanes, a new scaffold for bidentate bisphosphanes
Laborde, Coralie,Wei, Muh-Mei,Van Der Lee, Arie,Deydier, Eric,Daran, Jean-Claude,Volle, Jean-No?l,Poli, Rinaldo,Pirat, Jean-Luc,Manoury, Eric,Virieux, David
, p. 12539 - 12545 (2015)
A highly convergent synthesis of bis(triazolylphosphane oxides) was developed by a tandem copper-mediated Huisgen reaction-oxidative coupling. The phosphane oxides were reduced by trichlorosilane and the coordination of the resulting bisphosphanes was stu
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.
Synthesis and structural characterization of palladium dicarbene complexes bearing labile co-ligands
Huynh, Han Vinh,Seow, Hui Xian
, p. 983 - 987 (2009)
Dicarbene complexes [Pd(OAc)2(diNHC)] (2), [Pd(O 2CCF3)2(diNHC)] (3), and [Pd(CNCH 3)2(diNHC)](SO3CF3)2 (4) bearing labile acetato, fluoroacetato, and aceto
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
Reusable Co-nanoparticles for general and selectiveN-alkylation of amines and ammonia with alcohols
Beller, Matthias,Gawande, Manoj B.,Jagadeesh, Rajenahally V.,Kadam, Ravishankar G.,Li, Xinmin,Ma, Zhuang,Petr, Martin,Zbo?il, Radek,Zhou, Bei
, p. 111 - 117 (2022/01/06)
A general cobalt-catalyzedN-alkylation of amines with alcohols by borrowing hydrogen methodology to prepare different kinds of amines is reported. The optimal catalyst for this transformation is prepared by pyrolysis of a specific templated material, which is generatedin situby mixing cobalt salts, nitrogen ligands and colloidal silica, and subsequent removal of silica. Applying this novel Co-nanoparticle-based material, >100 primary, secondary, and tertiary amines includingN-methylamines and selected drug molecules were conveniently prepared starting from inexpensive and easily accessible alcohols and amines or ammonia.
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.
Chiral cyclometalated iridium complexes for asymmetric reduction reactions
Smith, Jennifer,Kacmaz, Aysecik,Wang, Chao,Villa-Marcos, Barbara,Xiao, Jianliang
supporting information, p. 279 - 284 (2021/01/18)
A series of chiral cyclometalated iridium complexes have been synthesised by cyclometalating chiral 2-aryl-oxazoline and imidazoline ligands with [Cp?IrCl2]2. These iridacycles were studied for asymmetric transfer hydrogenation reactions with formic acid as the hydrogen source and were found to display various activities and enantioselectivities, with the most effective ones affording up to 63% ee in the asymmetric reductive amination of ketones and 77% ee in the reduction of pyridinium ions. This journal is
Rational design of simple organocatalysts for the hsicl3 enantioselective reduction of (E)-n-(1-phenylethylidene)aniline
Burguete, Maria Isabel,García-Verdugo, Eduardo,Luis, Santiago V.,Maciá, María,Martí-Centelles, Vicente,Porcar, Raúl
, (2021/11/30)
Prolinamides are well-known organocatalysts for the HSiCl3 reduction of imines; however, custom design of catalysts is based on trial-and-error experiments. In this work, we have used a combination of computational calculations and experimental work, including kinetic analyses, to properly understand this process and to design optimized catalysts for the benchmark (E)-N-(1-phenylethylidene)aniline. The best results have been obtained with the amide derived from 4-meth-oxyaniline and the N-pivaloyl protected proline, for which the catalyzed process is almost 600 times faster than the uncatalyzed one. Mechanistic studies reveal that the formation of the component supramolecular complex catalyst-HSiCl3-substrate, involving hydrogen bonding breaking and costly conformational changes in the prolinamide, is an important step in the overall process.
Chiral Arylated Amines via C?N Coupling of Chiral Amines with Aryl Bromides Promoted by Light
Cao, Rui,Li, Jing-Sheng,Song, Geyang,Tang, Wei-Jun,Wang, Chao,Xiao, Jianliang,Xue, Dong,Yang, Liu,Zhang, Wei
supporting information, p. 21536 - 21542 (2021/08/23)
The Buchwald-Hartwig C-N coupling reaction has found widespread applications in organic synthesis. Over the past two decades or so, many improved catalysts have been introduced, allowing various amines and aryl electrophiles to be readily used nowadays. However, there lacks a protocol that could be used to couple a wide range of chiral amines and aryl halides, without erosion of the enantiomeric excess (ee). Reported in this article is a method based on molecular Ni catalysis driven by light, which enables stereoretentive C-N coupling of optically active amines, amino alcohols, and amino acid esters with aryl bromides, with no need for any external photosensitizer. The method is effective for a wide variety of coupling partners, including those bearing functional groups sensitive to bases and nucleophiles, thus providing a viable alternative to accessing synthetically important chiral N-aryl amines, amino alcohols, and amino acids esters. Its viability is demonstrated by 92 examples with up to 99 % ee.
