168749-62-0Relevant articles and documents
Cobalt-catalyzed asymmetric hydrogenation of ketones: A remarkable additive effect on enantioselectivity
Du, Tian,Wang, Biwen,Wang, Chao,Xiao, Jianliang,Tang, Weijun
supporting information, p. 1241 - 1244 (2020/10/02)
A chiral cobalt pincer complex, when combined with an achiral electron-rich mono-phosphine ligand, catalyzes efficient asymmetric hydrogenation of a wide range of aryl ketones, affording chiral alcohols with high yields and moderate to excellent enantioselectivities (29 examples, up to 93% ee). Notably, the achiral mono-phosphine ligand shows a remarkable effect on the enantioselectivity of the reaction.
Manganese-Catalyzed Enantioselective Hydrogenation of Simple Ketones Using an Imidazole-Based Chiral PNN Tridentate Ligand
Chen, Jiachen,Hou, Huacui,Ling, Fei,Nian, Sanfei,Wu, Feifei,Xu, Min,Yi, Xiao,Zhong, Weihui
supporting information, p. 285 - 289 (2020/02/18)
A series of Mn(I) catalysts containing imidazole-based chiral PNN tridentate ligands with controllable 'side arm' groups have been established, enabling the inexpensive base-promoted asymmetric hydrogenation of simple ketones with outstanding activities (up to 8200 TON) and good enantioselectivities (up to 88.5percent ee). This protocol features wide substrate scope and functional group tolerance, thereby providing easy access to a key intermediate of crizotinib.
Chiral ferrocene phosphine-nitrogen-nitrogen tridentate ligand as well as preparation method and application thereof
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Paragraph 0079-0082; 0084, (2019/10/01)
The invention discloses a chiral ferrocene phosphine-nitrogen-nitrogen tridentate ligand as well as a preparation method and an application thereof. The general structural formula of the chiral ferrocene phosphine-nitrogen-nitrogen tridentate ligand is shown in formula (I) or formula (II), wherein R1 and R2 are independently selected from C1-C6 alkyl, C3-C6 cycloalkyl, aryl or heterocyclic aryl respectively; R3 is aryl, heterocyclic aryl or C1-C6 alkyl, and R4 is hydrogen, C1-C6 alkyl, aryl or heterocyclic aryl; the general structural formula in the formula (I) and the formula (II) contains animidazole group or a substituted benzimidazole group respectively; one or more substituent groups exist on a benzene ring of the substituted benzimidazole group, and each substituent group is independently selected from H or C1-C4 alkyl. The chiral ferrocene phosphine-nitrogen-nitrogen tridentate ligand has the advantages that the tridentate ligand is convenient to synthesize, exists in the air stably and can be coordinated with cheap metal to prepare a cheap metal catalyst, and the cheap metal catalyst is well applied to asymmetric hydrogenation reactions of ketone.
Bimetallic Catalysis: Asymmetric Transfer Hydrogenation of Sterically Hindered Ketones Catalyzed by Ruthenium and Potassium
Slagbrand, Tove,Kivij?rvi, Tove,Adolfsson, Hans
, p. 3445 - 3449 (2015/11/10)
An efficient protocol for the asymmetric reduction of sterically hindered ketones under transfer-hydrogenation conditions was developed. The corresponding chiral alcohols were obtained in good to excellent yields with enantiomeric excess values up to 99 %. The role of the cation associated with the base present in the reduction reaction was investigated. In contrast to previous studies on this catalyst system, potassium ions rather than lithium ions significantly enhanced the reaction outcome.
AZAINDOLE COMPOUNDS, SYNTHESIS THEREOF, AND METHODS OF USING THE SAME
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Paragraph 0168; 0225; 0226, (2015/02/18)
The invention provides compounds of formula (I) and methods of treating a Mycobacterium infection or tuberculosis, or inhibiting DprE1 with the same.
Bi-aryl rotation in phenyl-dihydroimidazoquinoline catalysts for kinetic resolution of arylalkyl carbinols
Wang, Zheng,Ye, Jinjin,Wu, Rui,Liu, Yang-Zi,Fossey, John S.,Cheng, Jiagao,Deng, Wei-Ping
, p. 1909 - 1913 (2014/06/24)
Chiral nucleophilic catalysts, 6-aryl-phenyl-dihydroimidazoquinolines (PIQs), were designed, synthesised and applied to the kinetic resolution of arylalkyl carbinols with very high selectivity (S) factors (up to 530). Density functional theory calculations indicate that multiple noncovalent interactions play a key role in chiral recognition between 6-aryl-PIQ catalysts and chiral secondary alcohol substrates. The Royal Society of Chemistry 2014.
Selective reduction of ketones using water as a hydrogen source under high hydrostatic pressure
Tomin, Anna,Lazarev, Alexander,Bere, Matthew P.,Redjeb, Hana,T?r?k, Béla
experimental part, p. 7321 - 7326 (2012/09/22)
A selective reduction of a broad variety of ketones is described. The method is based on the combination of a Ni-Al alloy and high hydrostatic pressure (HHP, 2.8 kbar) in an aqueous medium. The reaction of the Ni-Al alloy with water provides in situ hydrogen generation and the high pressure ensures that the H2 formed remains in the solution, thus the CO reduction readily occurs. The application of the HHP resulted in selective formation of the desired products and the common problem of non-selective overhydrogenation could be avoided. In most cases the reductions resulted in high yields and excellent selectivities without the use of any base.
NBu4NI-catalyzed direct synthesis of α-ketoamides from aryl methyl ketones with dialkylformamides in water using TBHP as oxidant
Mai, Wen-Peng,Wang, Hui-Hui,Li, Zhi-Cheng,Yuan, Jin-Wei,Xiao, Yong-Mei,Yang, Liang-Ru,Mao, Pu,Qu, Ling-Bo
supporting information, p. 10117 - 10119 (2012/10/30)
A novel and easy practical direct synthesis of α-ketoamides has been developed without metals in water. This procedure was catalyzed by nBu 4NI using TBHP as oxidant from simple substrates, aryl methyl ketones and dialkylformamides. The Royal Society of Chemistry 2012.
Escherichia coli BioH: A highly enantioselective and organic solvent tolerant esterase for kinetic resolution of sec-alcohols
Wang, Bo,Tang, Xiaoling,Liu, Ji,Yu, Hongwei
supporting information; experimental part, p. 6360 - 6364 (2011/01/04)
Escherichia coli BioH, which is obligatory for biotin synthesis, was found to be an organic solvent tolerant esterase with high enantioselectivity for the kinetic resolution of sec-alcohols using free enzyme powder. With this esterase, a variety of racemic sec-alcohols were efficiently resolved with ee values of up to 99%.
Two-component supramolecular helical architectures: Creation of tunable dissymmetric cavities for the inclusion and chiral recognition of the third components
Kodama, Koichi,Kobayashi, Yuka,Saigo, Kazuhiko
, p. 2144 - 2152 (2008/02/04)
The inclusion and chiral recognition of racemic arylalkanols by supramolecular helical architectures consisting of enantiopure primary amines and achiral carboxylic acids were thoroughly studied. Among the architectures examined, a supramolecular helical architecture composed of the salt of enantiopure erythro-2-amino-1.2-diphenylethanol (1b) and benzoic acid (2a) was found to include a wide variety of racemic arylalkanols with recognition of their chirality. The helical architecture gave a dissymmetric 1D groove in the salt crystal, and the arylalkanols were enantioselectively included in the groove. The size and shape of the groove were tunable by proper selection of the achiral carboxylic acid component. The origin of the chiral recognition with the combination 1b/2a is discussed on the basis of X-ray crystallographic analyses.
