A sustainable two-phase procedure for V-catalyzed toluene oxidative bromination with H2O2–KBr

Galloni, Pierluca; Mancini, M.; Floris, Barbara

doi:10.1039/c3dt50907a

Cited by 34 publications

(20 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Furthermore, the monoperoxido vanadium complex was more reactive than the diperoxido complex toward the oxybromination of alkenes and alkynes; [27,32] recently good results have also been obtained in the benzylic bromination of toluene. [28] At higher reaction temperature (Entry 7), quantitative conversion of the substrate was observed, and the bromination reaction proceeded faster. However, it was accompanied by the oxidation of the substrate with hydrogen peroxide, which also led to the formation of 2-isopropyl-5-methyl-1,4-benzoquinone as byproduct.…”

Section: Resultsmentioning

confidence: 99%

“…Additionally, the oxidative bromination of toluene has been performed with the system described above, achieving the functionalization at the benzylic position. [28] The reaction has also been carried out without solvent, thus avoiding the use of chlorinated co-solvents to obtain products derived from the electrophilic aromatic substitution.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Thymol Bromination – A Comparison between Enzymatic and Chemical Catalysis

et al. 2015

Self Cite

View full text Add to dashboard Cite

An efficient three‐component reaction involving carbon monoxide with a range of aryl bromides and N‐substituted acetoacetamides is reported for the synthesis of β‐keto amides. This transformation is promoted by Pd‐catalysis followed by an acid‐mediated deacetylation upon work‐up, enabling a large number of β‐keto amides to be isolated. Finally, d2‐13C‐dyclonine could be synthesized in three steps utilizing the developed catalytic system as the key step.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Thymol Bromination – A Comparison between Enzymatic and Chemical Catalysis

et al. 2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…Quite recently, we have been involved in the study of the oxidative bromination of toluene, using NH 4 VO 3 as the catalyst [27]. Next to bromination products at the benzylic position, we found that, changing parameters, also benzaldehyde formation could be observed.…”

Section: Introductionmentioning

confidence: 93%

Sustainable Highly Selective Toluene Oxidation to Benzaldehyde

et al. 2021

Self Cite

View full text Add to dashboard Cite

Thanks to the well-recognized role of benzaldehyde in industry, nowadays the research of new and sustainable approaches to selectively synthesize such an interesting product is receiving great attention from the chemists’ community. In this paper, a V-based catalytic biphasic system is adopted to perform toluene oxidation to benzaldehyde. Importantly, to pursue sustainability, organic solvents have been avoided, so toluene is used as substrate and co-solvent, together with water. Also, the use of hydrophobic ionic liquids has been explored. To perform oxidation, NH4VO3 catalyst, H2O2, and a safe and inexpensive co-catalyst are used. Among the tested co-catalysts, KF and O2 were found to be the best choice, to guarantee good yields, in mild reaction conditions. In fact, with such a sustainable method, up to 30% of benzaldehyde can be obtained at 60 °C and, more interestingly, the oxidative system can be recharged, raising-up the yield. The entire process results highly selective, since no traces of benzyl alcohol or benzoic acid are detected. Hence, it constitutes a very appealing synthetic route, even suitable to be easily scaled-up at an industrial level.

show abstract

“…Importantly, the reactivity of vanadium-peroxo and molybdenum-diperoxo complexes is definitely superior than that of H 2 O 2 in oxidation reactions, therefore the oxidation of different alkanes, alkenes, alcohols, aromatic substrates, sulphides, as well as oxybromination reactions were successfully achieved with such catalytic systems [41][42][43][44]. Literature reports suggest that vanadate/peroxide oxidation system acts following substrate specifics in radical or ionic modes [38,41,45,46].…”

Section: Catalytic Systemsmentioning

confidence: 99%

Biomimetic Vanadate and Molybdate Systems for Oxidative Upgrading of Iono- and Organosolv Hard- and Softwood Lignins

et al. 2020

Self Cite

View full text Add to dashboard Cite

Recently reported acetosolv soft- and hardwood lignins as well as ionosolv soft- and hardwood lignins were transformed into monomeric aromatic compounds using either a vanadate or a molybdate-based catalyst system. Monomers were generated with remarkable, catalyst-dependent selectivity and high depolymerisation yields via oxidative exo- and endo-depolymerisation processes. Using the vanadate–hydrogen peroxide system on acetosolv pine lignin, vanillin and isovanillin were produced as main products with depolymerisation yields of 31%. Using the molybdate system on acetosolv and ionosolv lignin, vanillic acid was the practically exclusive product, with depolymerisation yields of up to 72%. Similar selectivities, albeit with lower depolymerisation yields of around 50% under standardised conditions, were obtained for eucalyptus acetosolv lignin, producing vanillin and syringaldehyde or vanillic acid as products, by using the vanadate- or the molybdate-based systems respectively.

show abstract

A sustainable two-phase procedure for V-catalyzed toluene oxidative bromination with H2O2–KBr

Cited by 34 publications

References 33 publications

Thymol Bromination – A Comparison between Enzymatic and Chemical Catalysis

Thymol Bromination – A Comparison between Enzymatic and Chemical Catalysis

Sustainable Highly Selective Toluene Oxidation to Benzaldehyde

Biomimetic Vanadate and Molybdate Systems for Oxidative Upgrading of Iono- and Organosolv Hard- and Softwood Lignins

Contact Info

Product

Resources

About