Power of Cooperativity: Lewis Acid-Lewis Base Bifunctional Asymmetric Catalysis

Kanai, Motomu; Kato, Norihiro; Ichikawa, Eiko; Shibasaki, Masakatsu

doi:10.1055/s-2005-869831

Cited by 357 publications

(78 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We developed various catalytic enantioselective cyanation and azidation reactions using chiral poly rare earth metal (RE) complexes derived from ligands 5-8 and TMSCN or TMSN 3 as a stoichiometric nucleophile [43,44]. General mechanism for those asymmetric catalyses is shown in Scheme 11.…”

Section: Catalytic Enantioselective Protonation Using Chiral Poly Gadmentioning

confidence: 99%

Multimetallic Multifunctional Catalysts for Asymmetric Reactions

Shibasaki

Kanai

Matsunaga

et al. 2011

Bifunctional Molecular Catalysis

Self Cite

View full text Add to dashboard Cite

The utility of several types of multimetallic asymmetric catalysts is reviewed. The appropriate design of multidentate chiral ligands provides homobimetallic, heterobimetallic, and polymetallic catalysts upon complexation with metal cations. Cooperative work of multiple catalytically active sites in the asymmetric multimetallic catalysts allows for enhanced catalytic activity and stereoselectivity over monometallic catalysts. Facile systematic tuning of the asymmetric multimetallic catalysts by manipulation of multidentate ligand structure and combination of metal cations enables the generation of diverse set of catalysts having distinct three-dimensional and catalytic properties, boosting the optimization process to identify the best catalyst for a specific reaction of interest.

show abstract

Section: Catalytic Enantioselective Protonation Using Chiral Poly Gadmentioning

confidence: 99%

Multimetallic Multifunctional Catalysts for Asymmetric Reactions

Shibasaki

Kanai

Matsunaga

et al. 2011

Bifunctional Molecular Catalysis

Self Cite

View full text Add to dashboard Cite

show abstract

“…For effective designs of monomeric metal species, 3,3 0 -disubstituted binaphthyl skeletons in BINOL and H 8 -BINOL are the most commonly accepted. In sharp contrast, chiral lithium(I) and magnesium (II) binaphtholates [4][5][6][7][8][9][10][11][12][13][14][15][16][17], which are usually prepared in situ from BuLi or Bu 2 Mg and chiral 3,3 0 -nonsubstituted BINOL or H 8 -BINOL, are practical acidbase combination catalysts [18][19][20][21][22], since the ligands are the simplest and the metals are abundant, inexpensive, harmless, and environmentally benign. However, unsurprisingly, enantioselective induction with high catalytic activity is sometimes problematic, due to their oligomeric or polymeric nature.…”

Section: General Properties Of Magnesium(ii) Binaphtholate Catalystsmentioning

confidence: 99%

Brønsted Acid/Lewis Base Hybrid Complexes

Hatano

Ishihara

2015

Topics in Organometallic Chemistry

View full text Add to dashboard Cite

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.

show abstract

“…They can be obtained by cyanosilylation of aldehydes and ketones using Me3SiCN (= E-Nu in Scheme 28 that produces the corresponding silyl ethers 53. The reaction is catalyzed by Lewis acids or bases, metal alkoxides, bifunctional catalysts, iodine, and inorganic salts [189,190]. As for the transesterifications that can be catalyzed by N-heterocyclic carbenes (NHC), the transfer of cyano group from Me3SiCN to a carbonyl compound has been catalyzed by diaminocarbenes [191].…”

Section: σ-And π-Nucleophiles As Catalysts For Nucleophilic Additionsmentioning

confidence: 99%

“…For instance, the enantioslective Michael addition of dimethyl malonate to cyclohex-2-enone is carried out on the kilogram scale (Scheme 33). It uses the bifunctional Lewis acid/Brønsted base catalyst 64 developed by Shibazaki and co-workers [190,[217][218][219]. Adduct 65 is the starting material in the synthesis of (−)-strychnine.…”

Section: Catalysis Of 14-(conjugate) Additionsmentioning

confidence: 99%

Organocatalysis: Fundamentals and Comparisons to Metal and Enzyme Catalysis

et al. 2016

View full text Add to dashboard Cite

Catalysis fulfills the promise that high-yielding chemical transformations will require little energy and produce no toxic waste. This message is carried by the study of the evolution of molecular catalysis of some of the most important reactions in organic chemistry. After reviewing the conceptual underpinnings of catalysis, we discuss the applications of different catalysts according to the mechanism of the reactions that they catalyze, including acyl group transfers, nucleophilic additions and substitutions, and C-C bond forming reactions that employ umpolung by nucleophilic additions to C=O and C=C double bonds. We highlight the utility of a broad range of organocatalysts other than compounds based on proline, the cinchona alkaloids and binaphthyls, which have been abundantly reviewed elsewhere. The focus is on organocatalysts, although a few examples employing metal complexes and enzymes are also included due to their significance. Classical Brønsted acids have evolved into electrophilic hands, the fingers of which are hydrogen donors (like enzymes) or other electrophilic moieties. Classical Lewis base catalysts have evolved into tridimensional, chiral nucleophiles that are N-(e.g., tertiary amines), P-(e.g., tertiary phosphines) and C-nucleophiles (e.g., N-heterocyclic carbenes). Many efficient organocatalysts bear electrophilic and nucleophilic moieties that interact simultaneously or not with both the electrophilic and nucleophilic reactants. A detailed understanding of the reaction mechanisms permits the design of better catalysts. Their construction represents a molecular science in itself, suggesting that sooner or later chemists will not only imitate Nature but be able to catalyze a much wider range of reactions with high chemo-, regio-, stereo-and enantioselectivity. Man-made organocatalysts are much smaller, cheaper and more stable than enzymes.

show abstract

Power of Cooperativity: Lewis Acid-Lewis Base Bifunctional Asymmetric Catalysis

Cited by 357 publications

References 19 publications

Multimetallic Multifunctional Catalysts for Asymmetric Reactions

Multimetallic Multifunctional Catalysts for Asymmetric Reactions

Brønsted Acid/Lewis Base Hybrid Complexes

Organocatalysis: Fundamentals and Comparisons to Metal and Enzyme Catalysis

Contact Info

Product

Resources

About