One-pot sequential oxidation and aldol-condensation reactions of veratryl alcohol catalyzed by the Ru@ZIF-8 + CuO/basic ionic liquid system

Fan, Honglei; Yang, Yingying; Song, Jinliang; Ding, Guodong; Wu, Congyi; Yang, Guanying; Han, Buxing

doi:10.1039/c3gc41363b

Cited by 54 publications

(31 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure shows conversion/selectivity (%) values with respect to time obtained in the Ru/ n ‐HT catalyzed aerobic oxidation of cinnamyl, vanillyl and veratryl alcohols, we found that Ru/ n ‐HT provided turnover frequency (TOF; TOF=mol of product/mol of ruthenium×time and all TOF values given here are not corrected to for the number of exposed surface atoms; that is, the values given are lower limits) values of 13.2, 5.1 and 11.4 h −1 for the aerobic oxidation of cinnamyl, vanillyl and veratryl alcohols, respectively. These TOF values are notably higher than those of obtained by Bi−Pt/Al 2 O 3 (2.1 h −1 for (1)), Pd/SWCNT (0.7 h −1 for (1)), MnFe 1.5 Ru 0.35 Cu 0.15 O 4 (7.9 h −1 for (1)), Au/CeO 2 (1.2 h −1 for (1)), CoMn 2 O 4 (3.1 h −1 for (2)), Co 3 O 4 (2.8 h −1 for (2)), Ru/Al 2 O 3 (1.8 h −1 for (3)), Ru/SiO 2 (1.6 h −1 for (3)), and Ru/ZIF‐8 (1.9 h −1 for (3)) catalysts tested in the aerobic oxidation of same substrates.…”

Section: Resultsmentioning

confidence: 99%

Nanohydrotalcite Supported Ruthenium Nanoparticles: Highly Efficient Heterogeneous Catalyst for the Oxidative Valorization of Lignin Model Compounds

et al. 2017

View full text Add to dashboard Cite

The catalytic transformation of lignocellulosic biomass derived chemicals into value‐added chemicals under mild conditions remains a challenge in the fields of synthetic chemistry and catalysis. Herein, we describe a new heterogeneous catalyst system that efficiently works in the oxidative valorization of lignin model compounds. This new heterogeneous catalyst system comprised of nano‐sized hydrotalcite (n‐HT; Mg6Al2(CO3)(OH)16) supported ruthenium(0) nanoparticles (Ru/n‐HT) was prepared by ion‐exchange of [Ru(OH2)Cl5]2− anions with the extraframework CO32− anions of n‐HT followed by their borohydride reduction (NaBH4) in water at room temperature. The characterization of Ru/n‐HT was done by the combination of various spectroscopic and the sum of their results revealed that the formation of well‐dispersed ruthenium(0) nanoparticles with a mean diameter of 3.2 ± 0.9 nm on the surface of n‐HT structure. The catalytic performance of Ru/n‐HT in terms of activity, selectivity and stability was tested in the aerobic oxidation of cinnamyl, veratryl and vanillyl alcohols, which are important lignin model compounds used to mimic the propyl side chain, the phenolic and non‐phenolic, respectively functional groups of lignin. We found that Ru/n‐HT nanocatalyst displays remarkable activity at high selectivity and almost complete conversion in these catalytic transformations under mild reaction conditions (at 373 K under 3 bar initial O2 pressure).

show abstract

Section: Resultsmentioning

confidence: 99%

Nanohydrotalcite Supported Ruthenium Nanoparticles: Highly Efficient Heterogeneous Catalyst for the Oxidative Valorization of Lignin Model Compounds

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Recently, Yamaguchi and Mizuno have reported RuO X supported on -alumina to be an effective and reusable heterogeneous catalyst for aerobic oxidation of both activated and non-activated alcohols in presence of sulfur, nitrogen and carbon-carbon double bonds [32]. Moreover, Ru-based catalysts have been demonstrated to play an important role in hydrogenation and hydrogenolysis reactions [31][32][33][34][35][36]. Combined, this makes Ru-based catalysts interesting to examine in the context of lignin valorization.…”

Section: Figmentioning

confidence: 99%

“…Moreover, such catalysts can often be recycled provided that the metal leaching is negligible and applied at elevated reaction temperatures. For the aerobic oxidation of VA a combined Ru-imidazolite/CuO ionic liquid catalyst system has been reported to yield up to 95% of VAld at 130 o C [31]. However, the recyclability of the catalyst system was not documented.…”

Section: Figmentioning

confidence: 99%

Aerobic Oxidation of Veratryl Alcohol to Veratraldehyde with Heterogeneous Ruthenium Catalysts

et al. 2015

View full text Add to dashboard Cite

Lignin is a complex polymeric molecule constituting various linkages between aromatic moieties.Typically, the -O-4 linkage accounts for more than half of the linkage structures present in lignin.The present study focuses on the oxidative transformation of veratryl alcohol (VA) -a compound Prolonged reaction time led to significant formation of the decarbonylated product veratrol from VAld. When the reaction was completed under 20 bars of argon in methanol instead of water, the methyl ether of VA (i.e. 1,2-dimethoxy-4-(methoxymethyl)benzene) prevailed, indicating that methanol protecting the hydroxyl group in VA from being oxidized to VAld. Catalysts containing alternative transition metals (Mn, Co, Cu and Ag) supported on Al 2 O 3 gave significantly lower activities compared to Ru/Al 2 O 3 under identical reaction conditions. The Ru/Al 2 O 3 catalyst was reused in three consecutive reaction runs in water, but a significantly lower VAld yield was obtained after the third cycle possibly due to leaching of Ru from the support.

show abstract

“…Despite the progresses in lignin depolymerisation process, many obstacles remain during its degradation pathway toward a practical application. Here we address critical impediments of previous studies.…”

Section: Introductionmentioning

confidence: 99%

TiN‐Cu Heterogeneous Nanocatalysts for Effective Depolymerisation of Oxidised Lignin

et al. 2018

View full text Add to dashboard Cite

Lignin is one of the important resource for production of aromatics from lignocellulosic biomass. Effective depolymerisation of lignin is dependent on improvement of successful strategies for production of lower blocks of chemicals from lignin. Herein, a successful strategy for lignin depolymerisation is proposed based on, a two-step selective oxidation and hydrogenolysis sequence, which efficiently cleaves lignin intermolecular bonds. The first step of this procedure is selective oxidation of lignin, which facilitates the lignin cleavage. The second step is hydrogenolysis conducted in the presence of titanium nitride supported copper (TiNÀCu) nanocatalysts. This two-step lignin depolymerization produced more than 56 wt % valuable single-ring aromatic compounds. The TiNÀCu nanocatalysts synthesised were inexpensive, effective and proven to have superior activity comparable to traditional noble metal based catalysts.

show abstract

One-pot sequential oxidation and aldol-condensation reactions of veratryl alcohol catalyzed by the Ru@ZIF-8 + CuO/basic ionic liquid system

Cited by 54 publications

References 26 publications

Nanohydrotalcite Supported Ruthenium Nanoparticles: Highly Efficient Heterogeneous Catalyst for the Oxidative Valorization of Lignin Model Compounds

Nanohydrotalcite Supported Ruthenium Nanoparticles: Highly Efficient Heterogeneous Catalyst for the Oxidative Valorization of Lignin Model Compounds

Aerobic Oxidation of Veratryl Alcohol to Veratraldehyde with Heterogeneous Ruthenium Catalysts

TiN‐Cu Heterogeneous Nanocatalysts for Effective Depolymerisation of Oxidised Lignin

Contact Info

Product

Resources

About