144789-75-3Relevant articles and documents
Synthesis of Air- and Moisture-Stable, Storable Chiral Oxorhenium Complexes and Their Application as Catalysts for the Enantioselective Imine Reduction
Das, Braja Gopal,Nallagonda, Rajender,Dey, Dhananjay,Ghorai, Prasanta
, p. 12601 - 12605 (2015/09/01)
Air-/moisture-stable, crystalline, and storable chiral salicyloxazoline based oxorhenium(V) complexes have been synthesized and their catalytic application for the asymmetric reduction of ketimines using hydrosilane as hydride source is disclosed. A broad substrate scope, high yields, and excellent enantioselectivities (up to 99 %) are attained. Furthermore, the syntheses of enantiopure α-amino esters, γ- and δ-lactams, and isoindolinones have also been carried out using this methodology. Finally, the method has been applied to synthetic targets of pharmaceutical relevance, such as R-(+)-salsolidine and R-(+)-crispine A.
CATALYST COMPOUNDS
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Paragraph 0314; 0324, (2015/03/28)
The present invention relates to an iridium-based catalyst compound for hydrogenating reducible moieties, especially imines and iminiums, the catalyst compounds being defined by the formulas: where ring B is either itself polycyclic, or ring B together with R is polycyclic. The catalysts of the invention are particularly effective in reductive amination procedures 10 which involve the in situ generation of the imine or iminium under reductive hydrogenative conditions.
Primary amines by transfer hydrogenative reductive amination of ketones by using cyclometalated IrIII catalysts
Talwar, Dinesh,Salguero, Noemi Poyatos,Robertson, Craig M.,Xiao, Jianliang
supporting information, p. 245 - 252 (2014/01/17)
Cyclometalated iridium complexes are found to be versatile catalysts for the direct reductive amination (DRA) of carbonyls to give primary amines under transfer-hydrogenation conditions with ammonium formate as both the nitrogen and hydrogen source. These complexes are easy to synthesise and their ligands can be easily tuned. The activity and chemoselectivity of the catalyst towards primary amines is excellent, with a substrate to catalyst ratio (S/C) of 1000 being feasible. Both aromatic and aliphatic primary amines were obtained in high yields. Moreover, a first example of homogeneously catalysed transfer-hydrogenative DRA has been realised for β-keto ethers, leading to the corresponding β-amino ethers. In addition, non-natural α-amino acids could also be obtained in excellent yields with this method. Reduce the work! A broad range of ketones have been successfully aminated to afford primary amines under transfer-hydrogenation conditions by using ammonium formate as the amine source and 0.1 mol % of a cyclometalated IrIII catalyst (see scheme). Copyright
CATALYST COMPOUNDS
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Paragraph 00163; 00173, (2013/11/05)
The present invention relates to an iridium-based catalyst compound for hydrogenating reducible moieties, especially imines and iminiums, the catalyst compounds being defined by the formulas: where ring B is either itself polycyclic, or ring B together with R is polycyclic. The catalysts of the invention are particularly effective in reductive amination procedures 10 which involve the in situ generation of the imine or iminium under reductive hydrogenative conditions.
Highly enantioselective titanium-catalyzed cyanation of imines at room temperature
Seayad, Abdul Majeed,Ramalingam, Balamurugan,Yoshinaga, Kazuhiko,Nagata, Takushi,Chai, Christina L. L.
supporting information; experimental part, p. 264 - 267 (2010/03/24)
(Figure presented) A highly active and enantioselective titanium-catalyzed cyanatlon of imines at room temperature Is described. The catalyst used Is a partially hydrolyzed titanium alkoxide (PHTA) precatalyst together with a readily available N-salicyl-β-aminoalcohol ligand. Up to 98% ee was obtained with quantitative yields In 15 min of reaction time using 5 mol % of the catalyst. Various N-protecting groups such as benzyl, benzhydryl, Boc, and PMP are tolerated.
Reaction of organolead triacetates with 4-ethoxycarbonyl-2-methyl-4,5-dihydro-1,3-oxazol-5-one. The synthesis of α-aryl- and α-vinyl-N-acetylglycines and their ethyl esters and their enzymic resolution
Morgan, Jacqueline,Pinhey, John T.,Sherry, Christopher J.
, p. 613 - 619 (2007/10/03)
4-Ethoxycarbonyl-2-methyl-4,5-dihydro-1,3-oxazol-5-one 7, which may be readily obtained from diethyl acetamidomalonate, undergoes high-yielding arylation and vinylation at the 4-position with organolead triacetates to give compounds which may be hydrolysed to give either the α-aryl- or α-vinyl-N-acetylglycine or the corresponding ethyl ester. The kinetic resolution of a number of these derivatives by enzymic hydrolysis of either the amide or ester function has been demonstrated.
Synthesis of Optically Active Arylglycines by Photolysis of Optically Active (β-Hydroxyamino) Carbene-Chromium(0) Complexes
Vernier, Jean-Michel,Hegedus, Louis S.,Miller, David B.
, p. 6914 - 6920 (2007/10/02)
Photolysis of chromium complexes having the optically active amino alcohol (1R,2S)-(-)- or (1S,2R)-(+)-2-amino-1,2-diphenylethanol as the amino group produced aryl-substituted oxazinones in good yield with reasonable diastereoselectivity.Facile separation of diastereoisomers followed by mild reductive cleavage produced several arylglycines, having either electron-donating or withdrawing groups on the aromatic ring, in good overall yield and with excellent enantiomeric excess.
