Managing Highly Coordinative Substrates in Asymmetric Catalysis: A Catalytic Asymmetric Amination with a Lanthanum-Based Ternary Catalyst

Mashiko, Tomoyuki; Kumagai, Naoya; Shibasaki, Masakatsu

doi:10.1021/ja9052653

Cited by 107 publications

(59 citation statements)

References 89 publications

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“…Asymmetric Amination 14,17) The cat. A and La(NO 3 The enantiomeric excess of the obtained products was determined via HPLC; DAICEL CHIRALPAK AD-H, hexane-MeOH=95 : 5, 1.0 mL/min, 40°C, 254 nm, t R =7.8 min (S), 10.4 min (R).…”

Section: )mentioning

confidence: 99%

A Study of the Strength of a Template Molecule—A Functional Monomer Interaction That Affects the Performance of Molecularly Imprinted Polymers and Its Application to Chiral Amplification

Yasuyama

Matsunaga

Ando

et al. 2017

CHEMICAL & PHARMACEUTICAL BULLETIN

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A novel type of molecularly imprinted polymer (MIP), N-benzoyl-(S)-valine anilide-imprinted polymer (IP-2), was prepared using hydrogen-bonding interactions as a main force in the pre-polymerization step. The performance of the IP-2 was evaluated via batch procedure and compared with a (S)-valine anilideimprinted polymer (IP-1) that was prepared using an ionic interaction that is stronger than hydrogen bonding. Although both polymers showed a preferential adsorbability for (S)-amino acid derivatives, different performances were observed in terms of adsorbability and enantioselectivity. In addition, the IP-2 was able to recognize the enantiomer of a valine-derived chiral catalyst. This phenomenon was applied to a chiral amplification reaction, and a highly selective asymmetric Mannich-type amination was achieved using the combination of a racemic catalyst and a MIP.Key words molecularly imprinted polymer; chiral recognition; (S)-benzoyl amino acid anilide; asymmetric amplification Molecularly imprinted polymers (MIPs)1-3) have been energetically pursued in the field of molecular recognition, and various types of applications such as a stationary phase of HPLC, 4,5) solid-state extraction, 6) and chemical sensors 7,8) have been reported due to qualities such as synthetic simplicity, stability, and a high level of recognition selectivity.There are several methods for the preparation of imprinted polymers, including acid-base interaction, simple hydrogen bonding, dipole-dipole interaction, and hydrophobic interaction at the pre-polymerization step. Among these, the acidbase interaction 4,5,9) and/or hydrogen bonding 10,11) are mainly used due to the effectiveness of bonding strength in regards to the tailor-made construction of three-dimentional binding sites.Therefore, MIPs prepared using an acid-base interaction appear to show a higher level of performance than those without such an ionic interaction. However, unexpectedly, only a few reports 12) described the comparison of the different performances of MIPs between the presence of acid-base interaction and the absence of such a strong interaction. Therefore, it would be desirable to establish a new methodology, which would enable a convenient and precise comparison of the performance of MIPs that could lead to the development of a new type of MIP.We previously reported 13) the evaluation of basic (S)-amino acid anilide (such as (S)-1)-imprinted MIPs that were prepared using an acid-base interaction by batch procedure that allowed independent observation of adsorbability and selectivity, which were not precisely measured by a HPLC column system.In this paper we describe the evaluation of the performance of neutral (S)-N-benzoyl amino acid anilide (such as (S)-5)-imprinted MIPs, which were prepared in the presence of a weaker hydrogen-bonding interaction in the pre-polymerization step, by batch procedure. We also report a MIP with a (S)-N-benzoyl valine anilide cavity and its application to chiral amplification (Fig. 1). ExperimentalGeneral Ethylene glycol dimethac...

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Section: )mentioning

confidence: 99%

A Study of the Strength of a Template Molecule—A Functional Monomer Interaction That Affects the Performance of Molecularly Imprinted Polymers and Its Application to Chiral Amplification

Yasuyama

Matsunaga

Ando

et al. 2017

CHEMICAL & PHARMACEUTICAL BULLETIN

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“…According to the established mechanistic study by Shibasaki [58], Ishihara investigated the positive nonlinear effect in 1,4-addition between 1a and 2a and the initial rate kinetic study, so that three (R)-H 8 -BINOLs and two Mg(II) centers would be involved in the transition states. Moreover, ESI-MS analysis of the mixture of Bu 2 Mg, (R)-H 8 -BINOL, and H 2 O (2:3:2 molar ratio) in THF showed 1:1 and 1:2 complexes of Mg(II)/(R)-H 8 -BINOLate (Fig.…”

Section: Catalytic Enantioselective Addition Of Phosphorus Nucleophilmentioning

confidence: 99%

Brønsted Acid/Lewis Base Hybrid Complexes

Hatano

Ishihara

2015

Topics in Organometallic Chemistry

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Recent progress on our Brønsted acid/Lewis base hybrid complexes in some asymmetric catalyses is reviewed. Based on the rational design of conjugated acid-base catalysts, tailor-made supramolecular catalysts can show remarkable catalytic activity and higher-ordered selectivities that cannot be realized by ready-made single-molecule catalysts. The chiral supramolecular magnesium(II) binaphtholate complexes trigger the highly enantioselective 1,4-hydrophosphinylation and 1,2-hydrophosphonylation of α,β-unsaturated carbonyl compounds, direct Mannichtype reaction, and hetero-Diels-Alder reaction. Moreover, the advanced supramolecular catalysts are prepared in situ from chiral 3,3 0 -disubstituted binaphthols and biphenols, arylboronic acid, and B(C 6 F 5 ) 3 , for promoting the anomalous endo-/ exo-selective Diels-Alder reaction. The specific mechanism and deep insights into the possible key intermediates are discussed on the basis of rational design of chiral supramolecular Brønsted acid/Lewis base hybrid catalysts as artificial enzymes.

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“…Indeed, the catalytic asymmetric amination of 6 proceeded in a highly enantioselective manner with a range of substrates to produce a,a-disubstituted amino acid derivatives 7 bearing a tetrasubstituted stereogenic center (Table 1). 39) Mechanistic studies employing MS, NMR, and circular dichroism (CD) analysis, and Eyring plots, as well as several control and kinetic experiments suggested that the catalyst components of the ternary catalyst were in dynamic equilibrium between the associated and dissociated state, and a 1 : 1 : 1 ternary complex of La(NO 3 ) 3 · 6H 2 O/(R)-4a/H-DVal-O t Bu was likely involved in the transition state (Fig. 1).…”

Section: Catalytic Asymmetric Amination Of Succinimide Derivatives mentioning

confidence: 99%

Development of Atom-Economical Catalytic Asymmetric Reactions under Proton Transfer Conditions: Construction of Tetrasubstituted Stereogenic Centers and Their Application to Therapeutics

Kumagai

2011

CHEMICAL & PHARMACEUTICAL BULLETIN

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The development of atom-economical catalytic asymmetric reactions based on two distinct sets of catalyst, a rare earth metal/amide-based ligand catalyst and a soft Lewis acid/hard Brønsted base catalyst, is reviewed. These catalytic systems exhibit high catalytic activity and stereoselectivity by harnessing a cooperative catalysis through hydrogen bond/metal coordination and soft-soft interactions/hard-hard interactions, respectively. The effectiveness of these cooperative catalysts is clearly delineated by the high stereoselectivity in reactions with highly coordinative substrates, and the specific activation of otherwise low-reactive pronucleophiles under proton transfer conditions. The rare earth metal/amide-based ligand catalyst was successfully applied to catalytic asymmetric aminations, nitroaldol (Henry) reactions, Mannich-type reactions, and conjugate addition reactions, generating stereogenic tetrasubstituted centers. Catalytic asymmetric amination and anti-selective catalytic asymmetric nitroaldol reactions were successfully applied to the efficient enantioselective synthesis of therapeutic candidates, such as AS-3201 and the b b 3 -adrenoreceptor agonist, showcasing the practical utility of the present protocols. The soft Lewis acid/hard Brønsted base cooperative catalyst was specifically developed for the chemoselective activation of soft Lewis basic allylic cyanides and thioamides, which are otherwise low-reactive pronucleophiles. The cooperative action of the catalyst allowed for efficient catalytic generation of active carbon nucleophiles in situ, which were integrated into subsequent enantioselective additions to carbonyl-type electrophiles.

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Managing Highly Coordinative Substrates in Asymmetric Catalysis: A Catalytic Asymmetric Amination with a Lanthanum-Based Ternary Catalyst

Cited by 107 publications

References 89 publications

A Study of the Strength of a Template Molecule—A Functional Monomer Interaction That Affects the Performance of Molecularly Imprinted Polymers and Its Application to Chiral Amplification

A Study of the Strength of a Template Molecule—A Functional Monomer Interaction That Affects the Performance of Molecularly Imprinted Polymers and Its Application to Chiral Amplification

Brønsted Acid/Lewis Base Hybrid Complexes

Development of Atom-Economical Catalytic Asymmetric Reactions under Proton Transfer Conditions: Construction of Tetrasubstituted Stereogenic Centers and Their Application to Therapeutics

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