127633-95-8Relevant academic research and scientific papers
Minisci-Type Alkylation of N-Heteroarenes by N-(Acyloxy)phthalimide Esters Mediated by a Hantzsch Ester and Blue LED Light
Li, Jiacheng,Siang Tan, Suan,Kyne, Sara Helen,Wai Hong Chan, Philip
supporting information, p. 802 - 810 (2022/01/11)
A synthetic method that enables the Hantzsch ester-mediated Minisci-type C2-alkylation of quinolines, isoquinolines and pyridines by N-(acyloxy)phthalimide esters (NHPI) under blue LED (light emitting diode) light (456 nm) is described. Achieved under mild reaction conditions at room temperature, the metal-free synthetic protocol was shown to be applicable to primary, secondary and tertiary NHPIs to give the alkylated N-heterocyclic products in yields of 21–99%. On introducing a chiral phosphoric acid, an asymmetric version of the reaction was also realised and provided product enantiomeric excess (ee) values of 53–99%. The reaction mechanism was delineated to involve excitation of an electron-donor acceptor (EDA) complex, formed from weak electrostatic interactions between the Hantzsch ester and NHPI, which generates the posited radical species of the redox active ester that undergoes addition to the N-heterocycle.
Structural contributions to autocatalysis and asymmetric amplification in the soai reaction
Athavale, Soumitra V.,Simon, Adam,Houk,Denmark, Scott E.
, p. 18387 - 18406 (2020/11/17)
Diisopropylzinc alkylation of pyrimidine aldehydes-the Soai reaction, with its astonishing attribute of amplifying asymmetric autocatalysis-occupies a unique position in organic chemistry and stands as an eminent challenge for mechanistic elucidation. A n
PYRIDAZINONES AND METHODS OF USE THEREOF
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Page/Page column 208, (2019/04/11)
Disclosed are compounds according to Formula (A), and related tautomers and pharmaceutical compositions. Also disclosed are therapeutic methods, e.g., of treating kidney diseases, using the compounds of Formula (A).
New C2-symmetric six-membered carbene ligands for asymmetric diethylzinc addition of arylaldehydes
Zhou, Bihui,Li, Zijing,Yang, Chen,Li, Linlin,Fan, Limei,Huang, Hongxia,Li, Jie
, p. 1 - 10 (2018/06/27)
A series of new six-membered NHC precursors were prepared by simply esterification of their parent compounds. Their applicability in asymmetric diethylzinc addition of arylaldehydes has been demonstrated and the corresponding secondary alcohol was obtained with good yields and moderate enantioselectivities. (Figure pressented)
Stereoselective reduction of aromatic ketones by a new ketoreductase from Pichia glucozyma
Contente, Martina Letizia,Serra, Immacolata,Brambilla, Marta,Eberini, Ivano,Gianazza, Elisabetta,De Vitis, Valerio,Molinari, Francesco,Zambelli, Paolo,Romano, Diego
, p. 193 - 201 (2016/01/09)
A new NADPH-dependent benzil reductase (KRED1-Pglu) was identified from the genome of the non-conventional yeast Pichia glucozyma CBS 5766 and overexpressed in E. coli. The new protein was characterised and reaction parameters were optimised for the enantioselective reduction of benzil to (S)-benzoin. A thorough study of the substrate range of KRED1-Pglu was conducted; in contrast to most other known ketoreductases, KRED1-Pglu prefers space-demanding substrates, which are often converted with high stereoselectivity. A molecular modelling study was carried out for understanding the structural determinants involved in the stereorecognition experimentally observed and unpredictable on the basis of steric properties of the substrates. As a result, a new useful catalyst was identified, enabling the enantioselective preparation of different aromatic alcohols and hydroxyketones.
Third-Generation Amino Acid Furanoside-Based Ligands from d-Mannose for the Asymmetric Transfer Hydrogenation of Ketones: Catalysts with an Exceptionally Wide Substrate Scope
Margalef, Jèssica,Slagbrand, Tove,Tinnis, Fredrik,Adolfsson, Hans,Diéguez, Montserrat,Pàmies, Oscar
, p. 4006 - 4018 (2016/12/30)
A modular ligand library of α-amino acid hydroxyamides and thioamides was prepared from 10 different N-tert-butyloxycarbonyl-protected α-amino acids and three different amino alcohols derived from 2,3-O-isopropylidene-α-d-mannofuranoside. The ligand library was evaluated in the half-sandwich ruthenium- and rhodium-catalyzed asymmetric transfer hydrogenation of a wide array of ketone substrates, including simple as well as sterically demanding aryl alkyl ketones, aryl fluoroalkyl ketones, heteroaromatic alkyl ketones, aliphatic, conjugated and propargylic ketones. Under the optimized reaction conditions, secondary alcohols were obtained in high yields and in enantioselectivities up to >99%. The choice of ligand/catalyst allowed for the generation of both enantiomers of the secondary alcohols, where the ruthenium-hydroxyamide and the rhodium-thioamide catalysts act complementarily towards each other. The catalytic systems were also evaluated in the tandem isomerization/asymmetric transfer hydrogenation of racemic allylic alcohols to yield enantiomerically enriched saturated secondary alcohols in up to 98% ee. Furthermore, the catalytic tandem α-alkylation/asymmetric transfer hydrogenation of acetophenones and 3-acetylpyridine with primary alcohols as alkylating and reducing agents was studied. Secondary alcohols containing an elongated alkyl chain were obtained in up to 92% ee. (Figure presented.).
DMF Dimethyl Acetal as Carbon Source for α-Methylation of Ketones: A Hydrogenation-Hydrogenolysis Strategy of Enaminones
Borah, Ashwini,Goswami, Limi,Neog, Kashmiri,Gogoi, Pranjal
, p. 4722 - 4728 (2015/05/13)
A novel heterogeneous catalytic hydrogenation-hydrogenolysis strategy has been developed for the α-methylation of ketones via enaminones using DMF dimethyl acetal as carbon source. This strategy provides a very convenient route to α-methylated ketones using a variety of ketones without any base or oxidant. (Chemical Equation Presented).
Modular hydroxyamide and thioamide pyranoside-based ligand library from the sugar pool: New class of ligands for asymmetric transfer hydrogenation of ketones
Coll, Mercè,Pàmies, Oscar,Diéguez, Montserrat
, p. 2293 - 2302 (2014/07/21)
A large library of pyranoside-based hydroxyamide and thioamide ligands has been synthesized for asymmetric transfer hydrogenation in an attempt to expand the scope of the substrates to cover a broader range of challenging heteroaromatic and aryl/fluoroalkyl ketones. These ligands have the advantage that they are prepared from commercial D-glucose, D-glucosamine and α-amino acids, inexpensive natural chiral feedstocks. By carefully selecting the ligand components (substituents/configurations at the amide/thioamide moiety, the position of amide/thioamide group and the configuration at C-2), we found that pyranoside-based thioamide ligands provided excellent enantioselectivities (in the best cases, ees of >99% were achieved) in a broad range of ketones, including the less studied heteroaromatics and challenging aryl/fluoroalkyls. Note that both enantiomers of the reduction products can be obtained with excellent enantioselectivities by simply changing the absolute configuration of the thioamide substituent.
Discovery of potent and simplified piperidinone-based inhibitors of the MDM2-p53 interaction
Yu, Ming,Wang, Yingcai,Zhu, Jiang,Bartberger, Michael D.,Canon, Jude,Chen, Ada,Chow, David,Eksterowicz, John,Fox, Brian,Fu, Jiasheng,Gribble, Michael,Huang, Xin,Li, Zhihong,Liu, Jiwen,Lo, Mei-Chu,McMinn, Dustin,Oliner, Jonathan D.,Osgood, Tao,Rew, Yosup,Saiki, Anne Y.,Shaffer, Paul,Yan, Xuelei,Ye, Qiuping,Yu, Dongyin,Zhao, Xiaoning,Zhou, Jing,Olson, Steven H.,Medina, Julio C.,Sun, Daqing
supporting information, p. 894 - 899 (2014/09/17)
Continued optimization of the N-substituent in the piperidinone series provided potent piperidinone-pyridine inhibitors 6, 7, 14, and 15 with improved pharmacokinetic properties in rats. Reducing structure complexity of the N-alkyl substituent led to the discovery of 23, a potent and simplified inhibitor of MDM2. Compound 23 exhibits excellent pharmacokinetic properties and substantial in vivo antitumor activity in the SJSA-1 osteosarcoma xenograft mouse model.
N-alkylation of lactams with secondary heterobenzylic bromides
Yu, Ming,Stevenson, Karis,Zhou, Gene
supporting information, p. 5591 - 5594 (2014/12/11)
We herein report a general N-alkylation reaction of lactams with secondary heterobenzylic bromides. This methodology features mild reaction condition, moderate to high product isolation yield, and broad substrate scope. Good chemical and structural tolerance has also been demonstrated by both the secondary heterobenzylic bromides and lactam substrates.
