Ene reaction of allylbenzene and N-methylmaleimide in subcritical water and ethanol

Laitinen, Ari; Takebayashi, Yoshihiro; Kylänlahti, Irene; Yli‐Kauhaluoma, Jari; Sugeta, Tsutomu; Otake, Katsuto

doi:10.1039/b304959k

Cited by 12 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the process, ELP-DAAO was purified through an efficient and simple way in a sustainable manner, with no pollutants in the process water; the solvents used for the functionalization of carbon nanotubes were ethanol and DMSO, and the enzyme immobilization was performed in MES buffer. Ethanol, [51][52][53] DMSO, [54][55][56] and MES buffer 57 have been utilized as environmentally benign and green solvents. In addition, carbon nanotubes can be produced from a green process, 58 and the enzyme immobilized on carbon nanotubes can be easily recovered from the reaction media.…”

Section: Discussionmentioning

confidence: 99%

Specific immobilization ofd-amino acid oxidase on hematin-functionalized support mimicking multi-enzyme catalysis

Sun

Song

et al. 2015

Green Chem.

View full text Add to dashboard Cite

11 D-amino acid oxidase (DAAO) catalyzes oxidative deamination of D-amino acids to 12 yield corresponding α-keto acids, producing hydrogen peroxide (H 2 O 2 ). D-amino acid 13 oxidase was genetically modified by fusion to an elastin-like polypeptide (ELP). For 14 the enzyme immobilization, multi-walled carbon nanotubes (MWCNTs) were adopted 15 as the model support. MWCNTs were functionalized with hematin. ELP-DAAO was 16 immobilized on the functionalized CNTs by coupling to the hematin. The specific 17 immobilization enabled ELP-DAAO in proximity to the hematin at a molecular 18 distance. The molecular-distance proximity facilitated the immediate decomposition 19 of H 2 O 2 catalyzed by the hematin. The evolved oxygen was efficiently utilized to 20 oxidize the reduced cofactor FDA of DAAO, and H 2 O 2 was produced. The forming of 21 H 2 O 2  O 2  H 2 O 2 circle between the DAAO and hematin has been demonstrated to 22 be the driving force to accelerate the deamination reaction. The enzyme kinetics has 23shown that the ELP-DAAO/hematin-CNTs conjugate exhibited a catalysis efficiency 24 more than three times that of free ELP-DAAO, demonstrating its ability mimicking 25 multi-enzyme catalysis. The methodology for highly specific immobilization of 26 enzyme is not restricted to carbon nanotubes, and can be extended easily to other 1 micro and nanomaterials as supports for specific immobilization of oxidases. 2 3 19 peroxide can induce enzyme deterioration, and DAAO can be partially destroyed in 20 the presence of hydrogen peroxide. 21, 22 In addition, the evolved hydrogen peroxide 21 can lead to the by-product inhibition effect on the conversion processes. These two 22 aspects indicate that accumulation of hydrogen peroxide around the enzyme DAAO 23 can reduce the catalytic efficiency of the enzyme. 23 To decompose the evolved 24 hydrogen peroxide, the DAAO catalysis was carried out in the presence of catalase 25 and horseradish peroxidase, 24-26 and catalase was co-immobilized with DAAO on a 1 support. 10,11, 27, 28 On the other hand, D-Amino acid oxidases are flavoenzymes with a 2 non-covalently bound flavin adenine dinucleotide (FAD) cofactor. The coenzyme FAD 3 plays an important role in the activity of DAAO. 29-31 During the catalysis process, the 4 FAD cofactor is first reduced and subsequently reoxidized by molecular oxygen to 5 yield hydrogen peroxide. For efficient utilization of molecular oxygen from the 6 environment, Ghisla et al. investigated O 2 diffusion pathways to enhance reactivity, 32 7 Bolivar et al. studied real-time sensing of O 2 availability inside porous carriers to 8 quantify diffusional restrictions in DAAO immobilizates. 33 9 In this work, D-Amino acid oxidase was genetically modified by fusion to an 10 elastin-like polypeptide (ELP). Elastin-like polypeptides ELPs undergo a sharp and 11 reversible phase transition at a specific temperature, thus ELP-DAAO was purified 12 through phase transition, which has been demonstrated to be an efficient and simple 13 way for purifying the DAAO. Mult...

show abstract

Section: Discussionmentioning

confidence: 99%

Specific immobilization ofd-amino acid oxidase on hematin-functionalized support mimicking multi-enzyme catalysis

Sun

Song

et al. 2015

Green Chem.

View full text Add to dashboard Cite

show abstract

“…This is the first example of the formation of Schiff bases via the condensation of DAMN with aromatic aldehydes in water, without the use of catalysts. It would be worthwhile to explore the use of water at the subcritical temperature [24], a method known to be highly advantageous and environmentally friendly. The complete assignment of the 1 H and 13 C-NMR spectral data for this important type of compounds is also reported herein for the first time.…”

Section: Discussionmentioning

confidence: 99%

Revisiting the Reaction Between Diaminomaleonitrile and Aromatic Aldehydes: a Green Chemistry Approach

2006

View full text Add to dashboard Cite

Abstract:The reaction between diaminomaleonitrile (DAMN) and aldehydes and the resulting monoimines are well known. Since the standard reaction conditions involve the use of toxic solvents (typically methanol), we have sought to apply green chemistry principles to this reaction by either using water as the solvent without any catalysts or employing "solvent-free" conditions. The monoimines derived from DAMN are of interest as precursors for obtaining different heterocyclic systems and linear polymers. The methodologies used have significant advantages with regards to cost and environmental considerations.

show abstract

“…At 300 °C water exhibits a polarity and density similar to those of acetone at room temperature and subcritical water as a medium for the pericyclic ene reactions due to the high solubility of the reagents.…”

Section: Introductionmentioning

confidence: 97%

Unusual Nazarov Cyclization in Near-Critical Water

Leikoski

Kaunisto

Alkio

et al. 2005

Org. Process Res. Dev.

Self Cite

View full text Add to dashboard Cite

The Nazarov reaction of trans,trans-dibenzylidene acetone in near-critical water with or without additional carbon dioxide produces 2,3-diphenyl-2-cyclopentenone instead of the conventional Nazarov product, 3,4-disubstituted 2-cyclopentenone. The use of organic solvents and strong mineral acids, generally required for this reaction, is avoided by using water and carbonic acid as a proton source. After an optimization procedure, 38% yield of 2,3-diphenyl-2-cyclopentenone was obtained. The presence of carbon dioxide had a clear positive effect on yield.

show abstract

Ene reaction of allylbenzene and N-methylmaleimide in subcritical water and ethanol

Cited by 12 publications

References 12 publications

Specific immobilization ofd-amino acid oxidase on hematin-functionalized support mimicking multi-enzyme catalysis

Specific immobilization ofd-amino acid oxidase on hematin-functionalized support mimicking multi-enzyme catalysis

Revisiting the Reaction Between Diaminomaleonitrile and Aromatic Aldehydes: a Green Chemistry Approach

Unusual Nazarov Cyclization in Near-Critical Water

Contact Info

Product

Resources

About