124703-77-1Relevant academic research and scientific papers
Divergent Synthesis of Multisubstituted Unsymmetric Pyrroles and Pyrrolin-4-ones from Enamino Esters via Copper-Catalyzed Aerobic Dimerization
Chen, Zhi-Wei,Zheng, Lei,Liu, Jin
, p. 3051 - 3060 (2019)
A facile synthetic method to access multisubstituted unsymmetric pyrrole and pyrrolin-4-one derivatives is disclosed. In the presence of Cu(OAc)2 and KOAc, substituted pyrrole derivatives are produced in good yields (up to 93 %) through oxidative cyclization of enamino esters. Meanwhile, using CuCl2 and TFA (trifluoroacetic acid), pyrrolin-4-one derivatives are obtained in excellent yields (up to 94 %) through 1,2-aryl migration. A wide range of functional groups have been tolerated, and a reliable method for the synthesis of valuable multisubstituted pyrroles and pyrrolin-4-ones has been developed.
Synthesis of β-amino acid derivatives via copper-catalyzed asymmetric 1,4-reduction of β-(acylamino)acrylates
Wu, Yan,Qi, Shan-Bin,Wu, Fei-Fei,Zhang, Xi-Chang,Li, Min,Wu, Jing,Chan, Albert S. C.
, p. 1754 - 1757 (2011)
A new set of reaction conditions has been established to facilitate the copper-catalyzed enantioselective 1,4-reduction of β-(acylamino)acrylates toward a selection of β-alkyl-β-amino acid derivatives in high yields and with uniformly high ee values (up to 99%) irrespective of the use of (E)- or (Z)-substrates.
Cu-Mediated Expeditious Annulation of Alkyl 3-Aminoacrylates with Aryldiazonium Salts: Access to Alkyl N2-Aryl 1,2,3-Triazole-carboxylates for Druglike Molecular Synthesis
Liu, Hao-Nan,Cao, Hao-Qiang,Cheung, Chi Wai,Ma, Jun-An
, p. 1396 - 1401 (2020/02/22)
Alkyl N-aryl 1,2,3-triazole-carboxylates are important molecules or intermediates in medicinal chemistry, but the synthesis of N2-aryl counterparts remains elusive. Herein, we describe a Cu-mediated annulation reaction of alkyl 3-aminoacrylates with aryldiazonium salts, both of which are readily available substrates. Furthermore, alkyl 2-aminoacrylates are also viable substrates. Diverse alkyl N2-aryl 1,2,3-triazole-carboxylates and their analogues can be rapidly prepared under mild conditions. Especially, this protocol allows one to access several druglike variants of carbonic anhydrase inhibitors and celecoxib.
NOVEL RUTHENIUM CATALYSTS AND THEIR USE FOR ASYMMETRIC REDUCTION OF KETONES
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Page/Page column 24; 25, (2015/01/16)
Disclosed are novel ruthenium compounds of formula (Ia) and (Ib): wherein R1 and the moiety L ∩ L are defined herein. Also disclosed is a process for using these novel ruthenium compounds as catalysts for asymmetric hydrogenation and transfer hydrogenation of ketones with high reactivities and excellent selectivities.
Facile entry to an efficient and practical enantioselective synthesis of a polycyclic cholesteryl ester transfer protein inhibitor
Han, Zhengxu S.,Xu, Yibo,Fandrick, Daniel R.,Rodriguez, Sonia,Li, Zhibin,Qu, Bo,Gonnella, Nina C.,Sanyal, Sanjit,Reeves, Jonathan T.,Ma, Shengli,Grinberg, Nelu,Haddad, Nizar,Krishnamurthy, Dhileep,Song, Jinhua J.,Yee, Nathan K.,Pfrengle, Waldemar,Ostermeier, Markus,Schnaubelt, Juergen,Leuter, Zeno,Steigmiller, Sonja,Daeubler, Juergen,Stehle, Emanuel,Neumann, Lukas,Trieselmann, Thomas,Tielmann, Patrick,Buba, Annette,Hamm, Rainer,Koch, Gunter,Renner, Svenja,Dehli, Juan R.,Schmelcher, Florian,Stange, Christian,MacK, Juergen,Soyka, Rainer,Senanayake, Chris H.
supporting information, p. 4142 - 4145 (2014/10/15)
An efficient enantioselective synthesis of the chiral polycyclic cholesteryl ester transfer protein (CETP) inhibitor 1 has been developed. The synthesis was rendered practical for large scale via the development of a modified Hantzsch-type reaction to prepare the sterically hindered pyridine ring, enantioselective hydrogenation of hindered ketone 6 utilizing novel BIBOP-amino-pyridine derived Ru complex, efficient ICl promoted lactone formation, and a BF3 mediated hydrogenation process for diastereoselective lactol reduction. This efficient route was successfully scaled to produce multikilogram quantities of challenging CETP drug candidate 1.
Iridium-catalyzed hydrogenation of β-dehydroamino acid derivatives using monodentate phosphoramidites
Enthaler, Stephan,Erre, Giulia,Junge, Kathrin,Schroeder, Kristin,Addis, Daniele,Michalik, Dirk,Hapke, Marko,Redkin, Dmitry,Beller, Matthias
experimental part, p. 3352 - 3362 (2009/04/07)
The iridium-catalyzed asymmetric hydrogenation of 13 different β-dehydroamino acid derivatives to give optically active β-amino acid esters has been examined. Readily accessible monodentate octahydrobinaphthol- based phosphoramidites were used as chiral ligands. Good to excellent enantioselectivities and yields were obtained for the E isomers, whereas poorer catalyst performance was found for the Z isomers. Importantly, to obtain high enantioselectivity, substitution at the 3,3′-positions of the ligands was necessary. Enantioselectivities of up to 94% ee were achieved under optimized conditions. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Development of practical rhodium phosphine catalysts for the hydrogenation of β-dehydroamino acid derivatives
Enthaler, Stephan,Erre, Giulia,Junge, Kathrin,Holz, Jens,Boerner, Armin,Alberico, Elisabetta,Nieddu, Ilenia,Gladiali, Serafino,Beller, Matthias
, p. 568 - 577 (2012/12/31)
The rhodium-catalyzed asymmetric hydrogenation of various β-dehydroamino acid derivatives to give optically active β-amino acids has been examined. Chiral monodentate 4,5-dihydro-3H-dinaphthophosphepines, which are easily tuned and accessible in a multi-10-g scale, have been used as ligands. The enantioselectivity is largely dependent on the nature of the substituent at the phosphorous atom and on the structure of the substrate. Applying optimized conditions up to 94% ee was achieved.
Synthesis of a new chiral bisphospholane ligand for the Rh(I)-catalyzed enantioselective hydrogenation of isomeric β-acylamido acrylates
Holz, Jens,Monsees, Axel,Jiao, Haijun,You, Jinsong,Komarov, Igor V.,Fischer, Christine,Drauz, Karlheinz,Boerner, Armin
, p. 1701 - 1707 (2007/10/03)
The highly stereoselective synthesis of a chiral silylphospholane has been described, which can be advantageously used as a building block under base-free conditions for the construction of diphosphines related to DuPHOS. The utility of silylphospholane is shown in the synthesis of a new bisphospholane ligand 1 (MalPHOS), which is characterized by a maleic anhydride backbone. The ligand forms with Rh(I) a complex with a larger bite angle P-Rh-P than the analogue Me-DuPHOS complex. Both complexes have been tested in the asymmetric hydrogenation of unsaturated α- and β-amino acid precursors of pharmaceutical relevance. In several cases, the new catalyst was superior in comparison to the Me-DuPHOS complex, in particular when (Z)-configured β-acylamido acrylates were used as substrates.
