Scope of chemical fixation of carbon dioxide catalyzed by a bifunctional monomeric tungstate

Kamata, Keigo; Kimura, Toshihiro; Sunaba, Hanako; Mizuno, Noritaka

doi:10.1016/j.cattod.2013.09.054

Cited by 41 publications

(31 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, various types of POMs can be synthesized in both aqueous and organic media by control of the acidity, concentration, and temperature. Mizuno and co-workers were the first to focus on the high charge density of [WO4] 2− in comparison with the other polytungstates and applied [WO4] 2− to base-catalyzed reactions [38,[42][43][44][45]. Various tungstate structures including [WO4] 2− were optimized through density functional theory (DFT) calculations, and the basicities were estimated using the natural bond orbital (NBO) charges of the tungstate oxygen atoms.…”

Section: Monomeric Metalatesmentioning

confidence: 99%

“…Table 1. Despite the weaker basicity of [WO4] 2− (pKa of conjugate acid in water: 3.5), TBA2[WO4] exhibited much higher catalytic activity than the strong inorganic and organic bases for the chemical fixation of CO2 with various nucleophiles due to its bifunctional action towards CO2 and substrates [38,42,45]. The combination of TBA2[WO4] with various transition metal species such as Ag + and Rh 2+ was applicable to other base-catalyzed reactions that could not be accomplished with only [WO4] 2− [43,44,48,54].…”

Section: Monomeric Metalatesmentioning

confidence: 99%

“…Therefore, the low-energy catalytic fixation of CO 2 is highly desirable, and several effective catalytic systems have been reported [110][111][112][113][114][115][116]. Mizuno and co-workers reported that a simple monomeric tungstate TBA 2 [WO 4 ] could act as a highly efficient homogeneous catalyst for the chemical fixation of CO 2 with amines, 2-aminobenzonitriles, and propargylic alcohols to urea derivatives, quinazoline-2,4(1H,3H)-diones, and cyclic carbonates, respectively (Schemes 1-3) [38,42,45]. For the reaction of 1,2-phenylenediamine with CO 2 at atmospheric pressure (0.1 MPa), the reaction rate of TBA 2 [WO 4 ] was more than 48 times larger than those of other catalysts including other POMs and typical strong inorganic and organic bases.…”

Section: Chemical Fixation Of Comentioning

confidence: 99%

See 2 more Smart Citations

Base Catalysis by Mono- and Polyoxometalates

Kamata

Sugahara

2017

Catalysts

Self Cite

View full text Add to dashboard Cite

Abstract:In sharp contrast with acid-, photo-, and oxidation-catalysis by polyoxometalates, base catalysis by polyoxometalates has scarcely been investigated. The use of polyoxometalates as base catalysts have very recently received much attention and has been extensively investigated. Numerous mono-and polyoxometalate base catalyst systems effective for the chemical fixation of CO 2 , cyanosilylation of carbonyl compounds, and C-C bond forming reactions have been developed. Mono-and polyoxometalate base catalysts are classified into four main groups with respect to their structures: (a) monomeric metalates; (b) isopolyoxometalates; (c) heteropolyoxometalates; and (d) transition-metal-substituted polyoxometalates. This review article focuses on the relationship among the molecular structures, the basic properties, and the unique base catalysis of polyoxometalates on the basis of groups (a)-(d). In addition, reaction mechanisms including the specific activation of substrates and/or reagents such as the abstraction of protons, nucleophilic action toward substrates, and bifunctional action in combination with metal catalysts are comprehensively summarized.

show abstract

Section: Monomeric Metalatesmentioning

confidence: 99%

Section: Monomeric Metalatesmentioning

confidence: 99%

Section: Chemical Fixation Of Comentioning

confidence: 99%

See 1 more Smart Citation

Base Catalysis by Mono- and Polyoxometalates

Kamata

Sugahara

2017

Catalysts

Self Cite

View full text Add to dashboard Cite

show abstract

“…Due to low polarity of unsaturated CÀCb onds,t he cyclization step is usually ratedetermining.D BU, [112] MTBD [113] and other guanidines, [114] tertiary amines, [115] NHCs, [116] K 2 CO 3 [108] and various ILs have been used to stabilize the carbamate before cyclization ( Figure 15). [117][118][119][120] Experiments with guanidine catalysts [113] and tertiary amine bases [115] demonstrated that the reactions are not entirely dependent on the base strength. [113][114][115] However,only guanidines with pK a !…”

Section: Angewandte Chemiementioning

confidence: 99%

Pivotal Role of the Basic Character of Organic and Salt Catalysts in C−N Bond Forming Reactions of Amines with CO₂

Hulla

Dyson

2019

Angew Chem Int Ed

View full text Add to dashboard Cite

Organocatalysts promote a range of C−N bond forming reactions of amines with CO2. Herein, we review these reactions and attempt to identify the unifying features of the catalysts that allows them to promote a multitude of seemingly unrelated reactions. Analysis of the literature shows that these reactions predominantly proceed by carbamate salt formation in the form [BaseH][RR′NCOO]. The anion of the carbamate salt acts as a nucleophile in hydrosilane reductions of CO2, internal cyclization reactions or after dehydration as an electrophile in the synthesis of urea derivatives. The reactions are enhanced by polar aprotic solvents and can be either promoted or hindered by H‐bonding interactions. The predominant role of all types of organic and salt catalysts (including ionic liquids, ILs) is the stabilization of the carbamate salt, mostly by acting as a base. Catalytic enhancement depends on the combination of the amine, the base strength, the solvent, steric factors, ion pairing and H‐bonding. A linear relationship between the base strength and the reaction yield has been demonstrated with IL catalysts in the synthesis of formamides and quinazoline‐2,4‐diones. The role of organocatalysts in the reactions indicates that all bases of sufficient strength should be able to catalyze the reactions. However, a physical limit to the extent of a purely base catalyzed reaction mechanism should exist, which needs to be identified, understood and overcome by synergistic or alternative methods.

show abstract

“…[2][3][4][5] Recent studies reported that [WO 4 ] 2À acted as aL ewis base catalyst for CO 2 fixation. [6][7][8] It was also reported that [gHGeW 10 O 36 ] 7À showedB rønsted base catalysis for Knoevenagel condensation reactions. [9,10] The base catalysis was ascribed to the negativity of the Oa toms.…”

Section: Introductionmentioning

confidence: 99%

Lewis Base Catalytic Properties of [Nb₁₀O₂₈]⁶⁻ for CO₂ Fixation to Epoxide: Kinetic and Theoretical Studies

Hayashi

Yamazoe

Koyasu

et al. 2017

Chemistry An Asian Journal

View full text Add to dashboard Cite

Scope of chemical fixation of carbon dioxide catalyzed by a bifunctional monomeric tungstate

Cited by 41 publications

References 43 publications

Base Catalysis by Mono- and Polyoxometalates

Base Catalysis by Mono- and Polyoxometalates

Pivotal Role of the Basic Character of Organic and Salt Catalysts in C−N Bond Forming Reactions of Amines with CO₂

Lewis Base Catalytic Properties of [Nb₁₀O₂₈]⁶⁻ for CO₂ Fixation to Epoxide: Kinetic and Theoretical Studies

Contact Info

Product

Resources

About

Scope of chemical fixation of carbon dioxide catalyzed by a bifunctional monomeric tungstate

Cited by 41 publications

References 43 publications

Base Catalysis by Mono- and Polyoxometalates

Base Catalysis by Mono- and Polyoxometalates

Pivotal Role of the Basic Character of Organic and Salt Catalysts in C−N Bond Forming Reactions of Amines with CO2

Lewis Base Catalytic Properties of [Nb10O28]6− for CO2 Fixation to Epoxide: Kinetic and Theoretical Studies

Contact Info

Product

Resources

About

Pivotal Role of the Basic Character of Organic and Salt Catalysts in C−N Bond Forming Reactions of Amines with CO₂

Lewis Base Catalytic Properties of [Nb₁₀O₂₈]⁶⁻ for CO₂ Fixation to Epoxide: Kinetic and Theoretical Studies