108100-06-7Relevant articles and documents
Polystyrene-supported enantiopure 1,2-diamines: Development of a most practical catalyst for the asymmetric transfer hydrogenation of ketones
Marcos, Rocio,Jimeno, Ciril,Pericas, Miquel A.
, p. 1345 - 1352 (2011)
Chlorosulfonylated polystyrene, a commodity resin, reacts with enantiopure 1,2-diamines to afford, in a single step, high loading catalytic resins involving monosulfonylated 1,2-diamino moieties. These functional polymers form stable (p-cymene)ruthenium chloride [RuCl(p-cymene)] complexes that efficiently catalyze (down to S/C=150) the asymmetric transfer hydrogenation (ATH) of alkyl aryl ketones with formic acid-triethylamine under essentially solvent-free (down to 0.25 mLmmol-1) reaction conditions. Among these resins, the immobilized version of TsDPEN stands out as a most practical catalyst for ATH: Uniformly high enantioselectivities are achieved with its use at low catalyst loading, and the resin can be recycled with virtually no limits.
A Chiral Samarium-Based Catalyst for the Asymmetric Meerwein-Ponndorf-Verley Reduction
Evans, David A.,Nelson, Scott G.,Gagne, Michel R.,Muci, Alexander R.
, p. 9800 - 9801 (1993)
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Ruthenium(II) trerdentate CNN complexes: Superlative catalysts for the hydrogen-transfer reduction of ketones by reversible insertion of a carbonyl group into the Ru-H bond
Baratta, Walter,Chelucci, Giorgio,Gladiali, Serafino,Siega, Katia,Toniutti, Micaela,Zanette, Matteo,Zangrando, Ennio,Rigo, Pierluigi
, p. 6214 - 6219 (2005)
(Chemical Equation Presented) Very low loading and short reaction times are characteristic features of the quantitative reduction of different ketones using 2-propanol and terdentate [RuX(CNN)-(dppb)] (X = H, Cl (see structure); dppb = Ph2P(CH2)4PPh2) complexes prepared from 6-(4′-methylphenyl)-2-pyridyl-methylamine. The reduction apparently takes place by reversible insertion of the substrate into the Ru-H bond, thus leading to a RuII alkoxide.
Ruthenium-catalysed efficient asymmetric transfer hydrogenation of aromatic ketones using cinchona alkaloids as chiral ligands
Jiang, Heyan
, p. 761 - 763 (2013)
Cinchona alkaloid derivatives were applied in asymmetric transfer hydrogenation of aromatic ketones in a ruthenium catalytic system using i-PrOH as the hydrogen source. A series of aromatic ketones could be transfer-hydrogenated to the corresponding alcohols with good to excellent conversion and enantioselectivity. The best results were achieved using 9-amino(9-deoxy) epiquinidine as the ligand; the enantioselectivity with acetophenone and 2′-(trifluoromethyl)acetophenone could reach 90% ee.
Asymmetric hydrogenation of isobutyrophenone using a [(diphosphine) RuCl2 (1,4-diamine)] catalyst
Grasa, Gabriela A.,Zanotti-Gerosa, Antonio,Medlock, Jonathan A.,Hems, William P.
, p. 1449 - 1451 (2005)
(Chemical Equation Presented) The use of three chiral 1,4-diamines in the [(diphosphine) RuCl2 (diamine)] catalyst system is demonstrated in the hydrogenation of acetophenone. The use of a 1,4-diamine offers unique properties that allow tuning of the catalyst system. These include the first example of the use of a racemic diamine in combination with a chiral phosphine, which gives 95% ee in the hydrogenation of isobutyrophenone
Isonitrile Iron(II) complexes with chiral N2P2 macrocycles in the enantioselective transfer hydrogenation of ketones
Bigler, Raphael,Mezzetti, Antonio
, p. 6460 - 6463 (2014)
Bis(isonitrile) iron(II) complexes bearing a C2-symmetric N2P2 macrocyclic ligand, which are easily prepared from the corresponding bis(acetonitrile) analogue, catalyze the asymmetric transfer hydrogenation (ATH) of a broad scope of ketones in excellent yields (up to 98%) and with high enantioselectivity (up to 91% ee).
Asymmetric transfer hydrogenation catalyzed by mesoporous MCM-41-supported chiral Ru-complex
Sarkar, Shaheen M.,Yusoff, Mashitah Mohd,Rahman, Md. Lutfor
, p. 177 - 181 (2015)
Chiral N-sulfonyldiamine was successfully anchored on mesoporous MCM-41 silica. The MCM-41-supported chiral N-sulfonyldiamine was used as an efficient heterogeneous chiral ligand in the asymmetric transfer hydrogenation of ketones. This heterogeneous system offered satisfactory enantioselectivities up to 94% with excellent conversions.
Highly Enantioselective Transfer Hydrogenation of Polar Double Bonds by Macrocyclic Iron(II)/(NH)2P2 Catalysts
Bigler, Raphael,Mezzetti, Antonio
, p. 253 - 261 (2016)
We describe herein a new protocol for the synthesis of 2,2′-((1S,1′S)-ethane-1,2-diylbis(phenylphosphanediyl))dibenzaldehyde ((SP,SP)-5), which is the key intermediate in the synthesis of macrocyclic iron(II)/(NH)2P2 catalysts for the highly enantioselective transfer hydrogenation of polar double bonds. The dialdehyde (SP,SP)-5 was obtained as a single diastereoisomer and enantiomer from an optically pure H-phosphinate in 33% yield over five steps. It was further converted to afford multigram quantities of the macrocyclic iron(II)/(NH)2P2 complexes, which were tested in the asymmetric transfer hydrogenation of aryl alkyl ketones and imines in 2-propanol on a 100 mmol scale. Ten substrates, including challenging ones such as tert-butyl phenyl ketone and industrially relevant molecules such as 3,5-bis(trifluoromethyl)acetophenone, were reduced in high yield (89.0-99.7%), excellent enantioselectivity (95.8-99.4% ee), and with low catalyst loadings (S/C up to 10 000/1).
Biotransformation of Aromatic Ketones by Linum usitatissimum
Tavares, Leonardo C.,Arriaga, Angela M. C.,De Lemos, Telma L. G.,Souza, Juliana M. O.,Teixeira, Maria V. S.,Santiago, Gilvandete M. P.
, p. 752 - 755 (2015)
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Asymmetric transfer hydrogenation of arylketones catalyzed by enantiopure ruthenium(II)/pybox complexes containing achiral phosphonite and phosphinite ligands
Claros, Miguel,Díez, Josefina,De Julián, Eire,Gamasa, M. Pilar,Lastra, Elena
, (2020)
A family of complexes of the formula trans-[RuCl2(L)(R-pybox)] (R-pybox = (S,S)-iPr-pybox, (R,R)-Ph-pybox, L = monodentate phosphonite, PPh(OR)2, and phosphinite, L = PPh2(OR), ligands) were screened in the catalytic asymmetric transfer hydrogenation of acetophenone, observing a strong influence of the nature of both the R-pybox substituents and the L ligand in the process. The best results were obtained with complex trans-[RuCl2{PPh2(OEt)}{(R,R)-Ph-pybox}] (2c), which provided high conversion and enantioselectivity (up to 96% enantiomeric excess, e.e.) for the reduction of a variety of aromatic ketones, affording the (S)-benzylalcohols.
Methylene-Bridged P-Chiral Diphosphines in Highly Enantioselective Reactions
Yamanoi, Yoshinori,Imamoto, Tsuneo
, p. 2988 - 2989 (1999)
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The first Ru(II)-catalysed asymmetric hydrogen transfer reduction of aromatic ketones in aqueous media
Rhyoo,Park,Chung
, p. 2064 - 2065 (2001)
The first water-soluble asymmetric hydrogen-transfer ruthenium(II) catalyst system consisting of [Ru(p-cymene)Cl2]2, (S)-proline amide, and sodium formate, which gives high conversion rates with high ee values up to 95.3% and is reus
2-Aryl-4,4,8-trimethyl-2-phosphabicyclo[3.3.0]octanes: Reactive chiral phosphine catalysts for enantioselective acylation
Vedejs, Edwin,Daugulis, Olafs
, p. 5813 - 5814 (1999)
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Chiral amino-urea derivatives of (1R,2R)-1,2-diaminocyclohexane as ligands in the ruthenium catalysed asymmetric reduction of aromatic ketones by hydride transfer
Bied, Catherine,Moreau, Joel J.E.,Wong Chi Man, Michel
, p. 329 - 336 (2001)
Several new chiral urea and thiourea ligands have been prepared by reaction of (1R,2R)-1,2-diaminocyclohexane with various organic isocyanates and isothiocyanates. These were used as ligands in the ruthenium catalysed enantioselective reduction of aromati
Use of surfactants in water-soluble ruthenium(II) complex-catalyzed asymmetric hydrogen-transfer reduction of aromatic ketones
Rhyoo, Hae Yoon,Park, Hee-Jung,Suh, Won Hyuk,Chung, Young Keun
, p. 269 - 272 (2002)
The introduction of surfactants to the water-soluble Ru(II)-catalyzed asymmetric transfer hydrogenation of ketones led to an increase of the catalytic activity and reusability compared to the catalytic systems without surfactants
Rapid, room-temperature acylative kinetic resolution of sec-alcohols using atropisomeric 4-aminopyridine/triphenylphosphine catalysis
Spivey, Alan C.,Arseniyadis, Stellios,Fekner, Tomasz,Maddaford, Adrian,Leese, David P.
, p. 295 - 301 (2006)
Two new atropisomeric 4-aminopyridine-based nucleophilic catalysts containing terphenyl 'blocking groups' have been prepared and evaluated for kinetic resolution (KR) of aryl alkyl sec-alcohols. One of these biaryls is shown to be the most selective atropisomeric catalyst yet prepared for several sec-alcohols but its low reactivity makes it non-optimal for use at room temperature (rt). Optimisation of the conditions for conducting KRs at rt using a previously described catalyst (containing a phenyl blocking group) at the 1 mol% level indicates that PPh3 (1 equiv) is beneficial for enantioselectivity and allows KR of (±)-1-(naphthyl)ethanol in less than 30 min with s>15 (i.e., ~40% recovered alcohol with >95% ee). These conditions constitute a convenient and practical method for rapid KR of sec-alcohols and are anticipated to facilitate a detailed kinetic study of this catalytic manifold by calorimetry.
Highly Enantioselective Ruthenium-Catalyzed Reduction of Ketones Employing Readily Available Peptide Ligands
Bogevig, Anders,Pastor, Isidro M.,Adolfsson, Hans
, p. 294 - 302 (2004)
Highly efficient and selective catalysts for the asymmetric reduction of aryl alkyl ketones under hydrogen-transfer conditions (2-propanol) were obtained by combining a novel class of pseudo-dipeptide ligands with [{RuCl 2(p-cymene)}2]. A library of 36 dipeptide-like ligands was prepared from N-Boc-protected α-amino acids and the enantiomers of 2-amino-1-phenylethanol and 1-amino-2-propanol. The catalyst library was evaluated with the reduction of acetophenone and excellent enantioselectivity of 1-phenylethanol was obtained with several of the novel catalysts. A ligand based on the combination of N-Boc-L-alanine and (S)-1-amino-2-propanol (ligand A-(S)-4) was found to be particular effective. When the situ formed ruthenium complex of this ligand was employed as the catalyst in the hydrogen-transfer reaction of various aryl alkyl ketones, the corresponding alcohol products were achieved in excellent enantioselectivity (up to 98% ee).
Asymmetric activation/deactivation of racemic Ru catalysts for highly enantioselective hydrogenation of ketonic substrates
Mikami, Koichi,Korenaga, Toshinobu,Ohkuma, Takeshi,Noyori, Ryoji
, p. 3707 - 3710 (2000)
By maximizing the difference in the catalytic activity between enantiomers of racemic catalysts, high enantioselectivity can be achieved in the hydrogenation of ketones. This is accomplished through a combination of asymmetric activation and deactivation (see scheme).
Remote chiral induction in the organocatalytic hydrosilylation of aromatic ketones and ketimines
Malkov, Andrei V.,Stewart Liddon, Angus J. P.,Ramirez-Lopez, Pedro,Bendova, Lada,Haigh, David,Kocovsky, Pavel
, p. 1432 - 1435 (2006)
(Chemical Equation Presented) Lewis basic, metal-free pyridyloxazolines catalyze the reduction of prochiral aromatic ketones and ketimines with Cl 3SiH in good enantioselectivity (up to 94% ee). Arene-arene interactions between the substrate and the catalyst are likely to play a role in the enantiodifferentiation process.
Osmium(II) CNN pincer complexes as efficient catalysts for both asymmetric transfer and H2 hydrogenation of ketones
Baratta, Walter,Ballico, Maurizio,Chelucci, Giorgio,Siega, Katia,Rigo, Pierluigi
, p. 4362 - 4365 (2008)
Catalysis at a pinch: Osmium CNN pincer complexes [OsCl(CNN)P2] (see graphic) are extremely active and productive catalysts for both the transfer and asymmetric hydrogenation of ketones (TOF ≈ 106 h -1 and TON ≈105). High enantioselectivity is achieved in the presence of only 0.005-0.002 mol% of the chiral osmium derivatives. [OsX(CNN)(dppb)] species with X = H and OR are involved in these catalytic TH and HY reactions. (Chemical Equation Presented)
Cinchona-Alkaloid-Derived NNP Ligand for Iridium-Catalyzed Asymmetric Hydrogenation of Ketones
Zhang, Lin,Zhang, Ling,Chen, Qian,Li, Linlin,Jiang, Jian,Sun, Hao,Zhao, Chong,Yang, Yuanyong,Li, Chun
supporting information, p. 415 - 419 (2022/01/12)
Most ligands applied for asymmetric hydrogenation are synthesized via multistep reactions with expensive chemical reagents. Herein, a series of novel and easily accessed cinchona-alkaloid-based NNP ligands have been developed in two steps. By combining [Ir(COD)Cl]2, 39 ketones including aromatic, heteroaryl, and alkyl ketones have been hydrogenated, all affording valuable chiral alcohols with 96.0-99.9% ee. A plausible reaction mechanism was discussed by NMR, HRMS, and DFT, and an activating model involving trihydride was verified.
Arene-Immobilized Ru(II)/TsDPEN Complexes: Synthesis and Applications to the Asymmetric Transfer Hydrogenation of Ketones
Doherty, Simon,Knight, Julian G.,Alshaikh, Hind,Wilson, James,Waddell, Paul G.,Wills, Corinne,Dixon, Casey M.
supporting information, p. 226 - 235 (2020/12/31)
The Noyori-Ikariya (arene)Ru(II)/TsDPEN precatalyst has been anchored to amorphous silica and DAVISIL through the η6-coordinated arene ligand via a straightforward synthesis and the derived systems, (arene)Ru(II)/TsDPEN@silica and (arene)Ru(II)/TsDPEN@DAVISIL, form highly efficient catalysts for the asymmetric transfer hydrogenation of a range of electron-rich and electron-poor aromatic ketones, giving good conversion and excellent ee's under mild reaction conditions. Moreover, catalyst generated in situ immediately prior to addition of substrate and hydrogen donor, by reaction of silica-supported [(arene)RuCl2]2 with (S,S)-TsDPEN, was as efficient as that generated from its preformed counterpart [(arene)Ru{(S,S)-TsDPEN}Cl]@silica. Gratifyingly, the initial TOFs (up to 1085 h?1) and ee's (96–97 %) obtained with these catalysts either rivalled or outperformed those previously reported for catalysts supported by either silica or polymer immobilized through one of the nitrogen atoms of TsDPEN. While the high ee's were also maintained during recycle studies, the conversion dropped steadily over the first three runs due to gradual leaching of the ruthenium.
Ruthenium-catalyzed hydrogenation of aromatic ketones using chiral diamine and monodentate achiral phosphine ligands
Wang, Mengna,Zhang, Ling,Sun, Hao,Chen, Qian,Jiang, Jian,Li, Linlin,Zhang, Lin,Li, Li,Li, Chun
, (2021/03/24)
The Ru-catalyzed asymmetric hydrogenation of ketones with chiral diamine and monodentate achiral phosphine has been developed. A wide range of ketones were hydrogenated to afford the corresponding chiral secondary alcohols in good to excellent enantioselectivities (up to 98.1% ee). In addition, an appropriate mechanism for the asymmetric hydrogenation was proposed and verified by NMR spectroscopy.