1441-20-9Relevant academic research and scientific papers
Asymmetric Umpolung Hydrogenation and Deuteration of Alkenes Catalyzed by Nickel
Guo, Siyu,Wang, Xiuhua,Zhou, Jianrong Steve
supporting information, p. 1204 - 1207 (2020/02/04)
Nickel-catalyzed asymmetric hydrogenation of several types of alkenes proceeds in high enantioselectivity, using acetic acid or water as the hydrogen source and indium powder as electron donor. The scope of alkenes herein include α,β-unsaturated esters, n
Chiral auxiliary recycling in continuous flow: Automated recovery and reuse of Oppolzer's sultam
Sullivan,Newman
, p. 2130 - 2134 (2018/03/05)
The telescoping of a three-stage, chiral auxiliary-mediated transformation in flow is described, including continuous separation of the product and auxiliary. The auxiliary can either be collected for later reuse, or directly fed back to the beginning of the process for recycling in real time, enabling each molecule of auxiliary to make multiple equivalents of chiral product and thus minimizing the step- and atom-economy issues associated with auxiliary-mediated synthesis. This concept is demonstrated for the asymmetric hydrogenation of olefins using Oppolzer's sultam, shortening the total reaction time >100 fold compared to batch, and demonstrating formal sub-stoichiometric auxiliary loading with respect to the process by automating auxiliary recycling within a closed loop.
Catalyst-Controlled Multicomponent Aziridination of Chiral Aldehydes
Mukherjee, Munmun,Zhou, Yubai,Dai, Yijing,Gupta, AniL K.,Pulgam, V. Reddy,Staples, Richard J.,Wulff, William D.
supporting information, p. 2552 - 2556 (2017/03/06)
A highly diastereoselective and enantioselective method for the multicomponent aziridination of chiral aldehydes has been developed with BOROX catalysts of the VANOL (3,3′-diphenyl-2,2′-bi-1-naphthol) and VAPOL (2,2′-diphenyl-(4-biphenanthrol)) ligands. Very high to perfect catalyst control is observed with most all substrates examined including aldehydes with chiral centers in the α- and β-positions. High catalyst control was also observed for a number of chiral heterocyclic aldehydes allowing for the preparation of epoxy aziridines, bis(aziridines) and ethylene diaziridines. Application of this reaction in the synthesis of β3-homo-d-alloisoleucine and β3-homo-l-isoleucine is reported.
N,N-Dimethylformamide as Hydride Source in Nickel-Catalyzed Asymmetric Hydrogenation of α,β-Unsaturated Esters
Guo, Siyu,Zhou, Jianrong
supporting information, p. 5344 - 5347 (2016/11/02)
Asymmetric transfer hydrogenation of α,β-unsaturated esters is realized by using a nickel/bisphosphine catalyst and N,N-dimethylformamide (DMF) as the hydride source.
Asymmetric NaBH4 1,4-reduction of C3-disubstituted 2-propenoates catalyzed by a diamidine cobalt complex
Shuto, Yoshihiro,Yamamura, Tomoya,Tanaka, Shinji,Yoshimura, Masahiro,Kitamura, Masato
, p. 1547 - 1550 (2015/05/27)
A new Co complex of a unique diamidine ligand catalyzes asymmetric NaBH4 reduction of C3-disubstituted (E)- and (Z)-2-propenoates, including C3-oxygen- and nitrogen-substituted substrates with high enantioselectivity. Analysis by X-ray diffract
Nickel-catalyzed asymmetric transfer hydrogenation of conjugated olefins
Guo, Siyu,Yang, Peng,Zhou, Jianrong
supporting information, p. 12115 - 12117 (2015/07/28)
Asymmetric transfer hydrogenation of electron-deficient olefins is realized with nickel catalysts supported by strongly σ-donating bisphosphines. Deuterium labeling experiments point to a reaction sequence of formate decarboxylation, asymmetric hydride in
Expanded scope of the asymmetric hydrogenation of minimally functionalized olefins catalyzed by iridium complexes with phosphite-thiazoline ligands
Mazuela, Javier,Pamies, Oscar,Dieguez, Montserrat
, p. 2410 - 2417 (2013/08/23)
We have replaced the oxazoline group with a thiazoline moiety in one of the most successful of the phosphite-oxazoline ligand families for the Ir-catalyzed hydrogenation of minimally functionalized olefins. A small but structurally important library of Ir phosphite-thiazoline precatalysts (Ir-L1-L2a-e) has been developed by changing the substituents/configurations at the biaryl phosphite group. We found that the replacement of the oxazoline with a thiazoline moiety in the ligand design is beneficial in terms of substrate scope.
Chiral ferrocenyl phosphine-phosphoramidite ligands for Cu-catalyzed asymmetric conjugate reduction of α,β-unsaturated esters
Hou, Chuan-Jin,Guo, Wei-Lei,Hu, Xiang-Ping,Deng, Jun,Zheng, Zhuo
experimental part, p. 195 - 199 (2011/05/02)
Unsymmetrical hybrid chiral ferrocenyl phosphine-phosphoramidite ligands have been applied for the first time in the Cu-catalyzed asymmetric 1,4-reduction of β-aryl substituted α,β-unsaturated esters. The results show that the ligand bearing (Sc/sub
Chiral NG-acylated hetarylpropylguanidine-type histamine H2 receptor agonists do not show significant stereoselectivity
Ghorai, Prasanta,Kraus, Anja,Birnkammer, Tobias,Geyer, Roland,Bernhardt, Günther,Dove, Stefan,Seifert, Roland,Elz, Sigurd,Buschauer, Armin
supporting information; experimental part, p. 3173 - 3176 (2010/09/05)
A set of chiral imidazolylpropylguanidines and 2-aminothiazolylpropylguanidines bearing NG-3-phenyl- or NG-3-cyclohexylbutanoyl residues was synthesized and investigated for histamine H2 receptor (H2R) agonism (guinea pig (gp) right atrium, GTPase assay on recombinant gp and human (h)H2R) and for hH2R selectivity compared to hH1R, hH3R and hH4R. In contrast to previous studies on arpromidine derivatives, the present investigation of acylguanidine-type compounds revealed only very low eudismic ratios (1.1-3.2), indicating the stereochemistry of the acyl moiety to play only a minor role in this series of H2R agonists.
Catalytic conjugate additions of geminal bis(sulfone)s: Expanding the chemistry of sulfones as simple alkyl anion equivalents
Landa, Aitor,Puente, Angel,Santos, J. Ignacio,Vera, Silvia,Oiarbide, Mikel,Palomo, Claudio
experimental part, p. 11954 - 11962 (2010/05/02)
The value of cyclic gem-bis-(sulfone) 4 as a simple alkyl nucleophile equivalent in catalytic C-C bondforming reactions is demonstrated. The 1,4-type nucleophilic additions of bis-(sulfone) 4 to α,β-unsaturated ketones take place by assistance of catalyti
