Selective Gas-phase Research Articles

B-166 Differentiation of Aziridine Functionality from Related Functional Groups in Protonated Analytes by Using Selective Ion-Molecule Reactions

Abstract Background The development of better methods for the rapid and reliable identification of unknown compounds in mixtures is urgently needed in drug development. Aziridines, in particular, are used for drug synthesis but are potentially mutagenic and carcinogenic compounds. However, the detection and identification of these compounds pose challenges for many analytical methods, such as Nuclear Magnetic Resonance (NMR) spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), and X-ray crystallography. These techniques are time-consuming and often require large quantities of highly pure compounds. Methods Therefore, this study demonstrates that selective gas-phase ion-molecule reactions of protonated analytes with neutral tris(dimethylamino)borane (TDMAB), followed by diagnostic collision-activated dissociation (CAD), can be used to differentiate aziridines from structurally related compounds in a modified linear quadrupole ion trap (LQIT) mass spectrometer. The experiments were performed using an atmospheric pressure chemical ionization (APCI) source in positive ion detection mode. TDMAB was purchased from Sigma-Aldrich and used without purification. It was introduced into the ion trap (2 mtorr of helium buffer gas) via an external reagent mixing manifold through a syringe pump at a flow rate of 10 μL h-1 and diluted with helium before entering the ion trap through a variable leak valve. All analytes were prepared at a concentration of 1 mM in methanol. The protonated analytes were transferred into the ion trap, isolated, and allowed to react with TDMAB (MS2 experiments). Results Product ions formed upon reactions of the analyte ions with TDMAB were subjected to a collision-activated dissociation (CAD) experiment (MS3 experiments). CAD on product ions produced diagnostic fragment ions with 25- and 43 m/z-units lower m/z values than the adduct - DMA product ions. Quantum chemical calculations were employed using the Gaussian 16 program calculated at the M06-2X/6-311++G(d,p) level of theory to provide theoretical foundation and to explore the underlying mechanisms of the observed gas-phase reactions. None of the tested structurally related analytes produced a similar fragmentation pattern Conclusions The innovative approach presented in this study offers a promising avenue for enhancing efficiency and accuracy in drug development. The successful differentiation of aziridine is an alternative method in overcoming the limitation of traditional techniques. The findings from the research contributes to the advancement of analytical techniques, addressing critical issues in identifying impurities in drug products. The versatility of the methods extends beyond drug developments, making it applicable in various other fields such as in molecular diagnostics, metabolism and laboratory medicines.

Selective Gas-Phase Depletion of Chemical Contaminants in Dissolved Organic Matter Increases Compositional Coverage by FT-ICR Mass Spectrometry.

Fourier transform ion cyclotron resonance mass spectrometry of dissolved organic matter (DOM) extracted from environmental samples provides molecular speciation that enables visualization of compositional trends in the fate and cycling of biogenic and anthropogenic organics. Often, chemical contamination is introduced during field sampling (i.e., remote locations, cannot use glass). Further, preconcentration of DOM by solid-phase extraction often results in chemical contamination. When chemical noise is a dominant fraction of the ion signal, mass spectral performance is degraded by reduction of the ion trap analyte accumulation capacity and enhanced ion cloud dephasing during ICR detection. We have developed gas-phase ion depletion of unwanted chemical contaminants during ion injection into the linear RF ion trap of the hybrid linear ion trap 21 T FT-ICR mass spectrometer that improves detection of analytes by removing unwanted chemical noise. We demonstrate improvements in signal-to-noise ratio, dynamic range, and the number of observed analytes in dissolved organic matter samples that results in a 40-100% increase in the number of identified analytes. In many cases, the number of peaks observed per nominal mass more than doubles over select m/z regions. This gas-phase "clean-up" can salvage precious samples challenged by sampling location, sample volume, or collection protocols that cannot be avoided and maximizes the compositional information obtained. Further, this approach is generalizable and extendable to any hybrid linear ion trap instrument platform (e.g., LTQ-Orbitrap or linear ion trap-TOF). We highlight the power of gas-phase depletion with electrospray ionization, but this method is also applicable to other ionization modes.

Converting waste tires into p-cymene through hydropyrolysis and selective gas-phase hydrogenation/dehydrogenation

The resource utilization and valorization of waste tires (WT) are of significant importance in reducing environmental pollution. To produce high-value p-cymene from WT, we propose a catalytic cascade process combining hydropyrolysis and catalytic gas-phase hydrotreating in a two-stage fixed-bed reactor. The effect of catalysts prepared with three different acidic supports on the hydrogenation/dehydrogenation of limonene, a compound derived from the hydropyrolysis of WT, was investigated. The p-cymene formation could be controlled by optimizing process parameters, including hydropyrolysis temperature, hydrogenation temperature, and catalyst-to-feedstock ratio (C/F). Experimental results indicated that, in the absence of a catalyst, limonene was the main product of WT depolymerization. Under optimized conditions (hydropyrolysis temperature of 425 ℃, hydrotreating temperature of 400 ℃, C/F of 10:1, and reaction pressure of 0.15 MPa), the highest relative content of p-cymene (79.1%) was obtained over the Pd/SBA-15 catalyst. This demonstrates that our proposed catalytic cascade process of hydropyrolysis and selective gas-phase hydrogenation/dehydrogenation can convert WT into p-cymene with high added value.

Selective Gas-Phase Hydrogenation of CO2 to Methanol Catalysed by Metal-Organic Frameworks.

Large scale production of green CH3 OH obtained from CO2 and green H2 is a highly wanted process due to the role of CH3 OH as H2 /energy carrier and for producing chemicals. Starting with a short summary of the advantages of metal-organic frameworks (MOFs) as catalysts in liquid-phase reactions, the present article highlights the opportunities that MOFs may offer also for some gas-phase reactions, particularly for the selective CO2 hydrogenation to CH3 OH. It is commented that there is a temperature compatibility window that combines the thermal stability of some MOFs with the temperature required in the CO2 hydrogenation to CH3 OH that frequently ranges from 250 to 300 °C. The existing literature in this area is briefly organized according to the role of MOF as providing the active sites or as support of active metal nanoparticles (NPs). Emphasis is made to show how the flexibility in design and synthesis of MOFs can be used to enhance the catalytic activity by adjusting the composition of the nodes and the structure of the linkers. The influence of structural defects and material crystallinity, as well as the role that should play theoretical calculations in models have also been highlighted.

Tuning the oxygen vacancy and acidity of V-Ag-Ce/TiO2 catalyst for selective gas-phase oxidation of toluene to benzaldehyde

Toluene gas-phase oxidation is a green, chlorine-free production process for benzaldehyde but its conversion efficiency is still unsatisfying due to the lack of highly efficient catalyst. Here the selective oxidation of toluene to benzaldehyde over V-Ag-Ce/TiO2 under an air atmosphere was investigated. The catalyst was prepared by impregnation and characterized by scanning electron microscope (SEM), N2 adsorption-desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Electron paramagnetic resonance (EPR), H2 temperature programmed reduction (H2-TPR), O2 temperature programmed desorption (O2-TPD), and NH3 temperature programmed desorption (NH3-TPD). The amount of oxygen vacancy and acid of the catalyst can be tuned through adjusting the V:Ag:Ce ratio. Over the optimum catalyst (V:Ag:Ce = 4:2:1, molar ratio), 92% benzaldehyde selectivity with a 27% toluene conversion can be obtained at 550 °C. Medium amounts of oxygen vacancy (0.43) and acidity (0.10 mmol/g) are found to be conducive to the conversion of toluene to benzaldehyde. This study has important theoretical guiding significance for improving conversion efficiency from toluene to benzaldehyde by gas-phase aerobic oxidation.

Boosted nitrilation of dimethyl adipate with NH3 to adiponitrile over bimetallic oxide: Synergetic effect between Nb and W

To reach highly active and selective gas-phase nitrilation of dimethyl adipate (DMA) with NH3, a series of NbxW10-x (x = 10, 9, 7, 5 and 0) composite were fabricated by a sol–gel method to approach the homogeneous combination of NbOx and WOx. As a result, the single-pass yield of adiponitrile (ADN) reached 85.2% over Nb9W1 under lower reaction temperature and lower NH3/DMA molar ratio. Consequently, the space–time yield (STY) of ADN over Nb9W1 was 1.7 ∼ 30 times higher than that of previous catalysts. Mechanistic experiments demonstrated the activity strongly correlates the interaction between the carbonyl functionality and the composite. Further, a significant synergistic effect between W and Nb was disclosed, wherein the Nb-based domains account for activating DMA while the W-based domains mainly adsorb and activate NH3 feedstock.

Differentiation of the Aziridine Functionality from Related Functional Groups in Protonated Analytes by Using Selective Ion-Molecule Reactions Followed by Collision-Activated Dissociation in a Linear Quadrupole Ion Trap Mass Spectrometer.

Aziridines are commonly used as reagents for the synthesis of drug substances although they are potentially mutagenic and genotoxic. Therefore, their unambiguous detection is critically important. Unfortunately, tandem mass spectrometry (MS2) based on collision-activated dissociation (CAD), a powerful method used for the identification of many unknown compounds in complex mixtures, does not provide diagnostic fragmentation patterns for ionized aziridines. Therefore, a different mass spectrometry approach based on MS3 experiments is presented here for the identification of the aziridine functionalities. This approach is based on selective gas-phase ion-molecule reactions of protonated analytes with tris(dimethylamino)borane (TDMAB) followed by diagnostic CAD reactions in a modified linear quadrupole ion trap (LQIT) mass spectrometer. TDMAB reacts with protonated aziridines by forming adduct ions that have lost a dimethylamine (DMA) molecule ([M + H + TDMAB - HN(CH3)2]+). CAD on these product ions generated diagnostic fragment ions with m/z-values 25- and 43-units lower than those of the ion-molecule reaction product ions. None of the ion-molecule reaction product ions formed from other, structurally related, protonated analytes produced related fragment ions. Quantum chemical calculations were employed to explore the mechanisms of the observed reactions.

Solar-driven gas phase photocatalytic CO2 methanation by multimetallic UiO-66 solids decorated with RuOx nanoparticles

As there is an urgent need to produce solar fuels from CO2, we here report on the development of a series of multimetallic UiO-66(Zr/Ce/Ti) solids-supported RuOx nanoparticles as photocatalysts for selective gas phase CO2 methanation by H2 under simulated sunlight irradiation. The trimetallic UiO-66(Zr/Ce/Ti) based-photocatalyst exhibits higher activity (1,900 μmol g−1 of CH4 after 22 h) than analogous mono- [UiO-66(Zr) or UiO-66(Ce)] and bimetallic [UiO-66(Zr/Ce) or UiO-66(Zr/Ti)] derivatives, as well as higher than previous reports on metal–organic frameworks (MOFs). The experimental evidence on the observed order of photocatalytic activity and insights into the occurrence of a dual photochemical and photothermal mechanism for the most active trimetallic sample were obtained by means of spectroscopic techniques including fluorescence and laser flash photolysis, photoelectrochemical and additional photocatalytic measurements. This study exemplifies the benefits of developing multimetallic MOF-supported metal nanoparticles to achieve high photocatalytic activity for solar-driven gas phase CO2 conversion.

Rhodium Single-Atom Catalyst Design through Oxide Support Modulation for Selective Gas-Phase Ethylene Hydroformylation.

A frontier challenge in single-atom (SA) catalysis is the design of fully inorganic sites capable of emulating the high reaction selectivity traditionally exclusive of organometallic counterparts in homogeneous catalysis. Modulating the direct coordination environment in SA sites, via the exploitation of the oxide support's surface chemistry, stands as a powerful albeit underexplored strategy. We report that isolated Rh atoms stabilized on oxygen-defective SnO2 uniquely unite excellent TOF with essentially full selectivity in the gas-phase hydroformylation of ethylene, inhibiting the thermodynamically favored olefin hydrogenation. Density Functional Theory calculations and surface characterization suggest that substantial depletion of the catalyst surface in lattice oxygen, energetically facile on SnO2 , is key to unlock a high coordination pliability at the mononuclear Rh centers, leading to an exceptional performance which is on par with that of molecular catalysts in liquid media.

Highly Selective Gas-Phase Catalytic Hydrogenation of Acetone to Isopropyl Alcohol

Current industrial synthesis procedures of isopropyl alcohol (IPA), by the direct or indirect hydration of propylene in the gas or liquid phase, suffer from the low conversion of propylene, the requirement for high pressure, and the harmfulness to the environment. In this context, we report a single-step, gas-phase process for the green synthesis of IPA via acetone hydrogenation, in a fixed-bed reactor, under ambient pressure and within a temperature range of 100–350 °C. Composite catalysts with various ratios of ruthenium nanoparticles supported on activated charcoal and nano-zinc oxide (n-Ru/AC/n-ZnO) were used. Catalytic activity and selectivity were functions of n-Ru/AC/n-ZnO loading ratios, reaction temperature, and the hydrogen to acetone molar ratio. The composite catalysts were characterized by X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), hydrogen temperature-programmed reduction (H2-TPR) analysis, and nitrogen physisorption. High yields of IPA were obtained over 3n-Ru/AC/2n-ZnO) catalyst, which showed the highest selectivity of 98.7% toward isopropyl alcohol and acetone conversion of 96.0% under a hydrogen to acetone mole ratio of 1.5 at 100 °C. Reaction rates, calculated from the model equation, were in reasonable agreement with those measured experimentally. The apparent activation energy (Ea) value for acetone hydrogenation was found to be 17.2 kJ/mol. This study proved that immobilized Ru catalysts were potential superior catalysts for the selective hydrogenation of acetone to IPA in exceptionally mild green synthesis conditions.

Functionalized ceria–niobium supported nickel catalysts for gas phase semi-hydrogenation of phenylacetylene to styrene

We illustrated a complete and selective gas phase hydrogenation of phenylacetylene into styrene over a Ni-NbCeOx catalyst. Optimum operational conditions for this reaction are presented.

Metal-free four-in-one modification of g-C3N4 for superior photocatalytic CO2 reduction and H2 evolution

Utilization of g-C3N4 as a single photocatalyst material without combination with other semiconductor remains challenging. Herein, we report a facile green method for synthesizing a metal free modified g-C3N4 photocatalyst. The modification process combines four different strategies in a one-pot thermal reaction: non-metal doping, porosity generation, functionalization with amino groups, and thermal oxidation etching. The as-prepared amino-functionalized ultrathin nanoporous boron-doped g-C3N4 exhibited a high specific surface area of 143.2 m2 g−1 which resulted in abundant adsorption sites for CO2 and water molecules. The surface amino groups act as Lewis basic sites to adsorb acidic CO2 molecules, which can also serve as active sites to facilitate hydrogen generation. Besides, the simultaneous use of ammonium chloride as a dynamic gas bubble template along with thermal oxidation etching efficiently boosts the delamination of the g-C3N4 layers to produce ultrathin sheets; this leads to stronger light–matter interactions and efficient charge generation. Consequently, the newly modified g-C3N4 achieved selective gas-phase CO2 reduction into CO with a production yield of 21.95 µmol g−1, in the absence of any cocatalyst. Moreover, a high hydrogen generation rate of 3800 µmol g-1h−1 and prominent apparent quantum yield of 10.6% were recorded. This work opens up a new avenue to explore different rational modifications of g-C3N4 nanosheets for the efficient production of clean energy.

Unassisted Highly Selective Gas-Phase CO2 Reduction with a Plasmonic Au/p-GaN Photocatalyst Using H2O as an Electron Donor

Surface plasmon resonances in metal nanostructures enable the generation of nonequilibrium hot electron–hole pairs, which has received wide interest as a means to drive chemical reactions at the na...

Selective Gas-Phase Functionalization of SiO2 and SiNx Surfaces with Hydrocarbons.

Selective functionalization of dielectric surfaces is required for area-selective atomic layer deposition and etching. We have identified precursors for the selective gas-phase functionalization of plasma-deposited SiO2 and SiNx surfaces with hydrocarbons. The corresponding reaction mechanism of the precursor molecules with the two surfaces was studied using in situ surface infrared spectroscopy. We show that at a substrate temperature of 70 °C, cyclic azasilanes preferentially react with an -OH-terminated SiO2 surface over a -NHx-terminated SiNx surface with an attachment selectivity of ∼5.4, which is limited by the partial oxidation of the SiNx surface. The cyclic azasilane undergoes a ring-opening reaction where the Si-N bond cleaves upon the reaction with surface -OH groups forming a Si-O-Si linkage. After ring opening, the backbone of the grafted hydrocarbon is terminated with a secondary amine, -NHCH3, which can react with water to form an -OH-terminated surface and release CH3NH2 as the product. The surface coverage of the grafted cyclic azasilane is calculated as ∼3.3 × 1014 cm-2, assuming that each reacted -OH group contributes to one hydrocarbon linkage. For selective attachment to SiNx over SiO2 surfaces, we determined the reaction selectivity of aldehydes. We demonstrate that aldehydes selectively attach to SiNx over SiO2 surfaces, and for the specific branched aliphatic aldehyde used in this work, almost no reaction was detected with the SiO2 surface. A fraction of the aldehyde molecules reacts with surface -NH2 groups to form an imine (Si-N═C) surface linker with H2O released as the byproduct. The other fraction of the aldehydes also reacts with surface -NH2 groups but do not undergo the water-elimination step and remains attached to the surface as an aminoalcohol (Si-NH-COH-). The surface coverage of the grafted aldehyde is calculated as ∼9.8 × 1014 cm-2 using a known infrared absorbance cross-section for the -C(CH3)3 groups.

High selective gas-phase rearrangement reaction of TCDD induced by excess electron attachment: Theoretical insight on the decomposition mechanism of one of the most toxic chemical known to science

Dioxins are highly toxic chemicals with serious health risks, for which there is no safe level of exposure. Because of the slow decomposition of dioxins, the removal of these persistent environmental pollutants still remains a challenge. Based on theoretical studies, the present work investigates the degradation mechanism of the most toxic type of dioxin-related compounds by low-energy electron irradiation. To explore the rearrangement manner of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced by excess electron attachment, the B3LYP-D3(BJ)/def2-TZVP//B3LYP-D3(BJ)/6–311++G(d,p) level of density functional theory was applied. Electron attachment resulted in a remarkable decrease in the activation barrier of the rearrangement reaction in a thermodynamically preferred reaction. An activation energy as low as 6.6 kcal/mol provides a strong demonstration that this pathway is the most effective in comparison to the neutral or radical rearrangement mechanisms. The attachment of electrons in the above energy range to C–Cl σ∗orbital is more likely than attachment to the LUMO of TCDD with π∗ orbital character. This σ∗ anion then undergoes a C–O σ bond rupture over a small barrier to produce a relatively stable intermediate, n-IM. The formed n-IM is again reactive toward a subsequent C–O bond rupture along with an intramolecular C–C coupling to produce the products, (E)-4,4′,5,5′-tetrachloro-[1,1′-bi(cyclohexylidene)]-3,3′,5,5′-tetraene-2,2′-dione and (Z)-4,4′,5,5′-tetrachloro-[1,1′-bi(cyclohexylidene)]-3,3′,5,5′-tetraene-2,2′-dione. The thermodynamic driving force for the anionic mechanism ensures the formation of the products to be irreversible enough to be purified. The purified products, with their active carbonyl groups, can react in many different ways with a wide range of nucleophile compounds.

Influence of the particle size on selective 2-propanol gas-phase oxidation over Co3O4 nanospheres

Co3O4 nanospheres with a preferential (110) surface orientation showed excellent catalytic properties in the selective gas-phase oxidation of 2-propanol. A preferential Mars–van Krevelen mechanism on the Co3O4(110) surface was identified by DFT + U.

Supported Cu Nanoparticles as Selective and Stable Catalysts for the Gas Phase Hydrogenation of 1,3-Butadiene in Alkene-Rich Feeds.

Supported copper nanoparticles are a promising alternative to supported noble metal catalysts, in particular for the selective gas phase hydrogenation of polyunsaturated molecules. In this article, the catalytic performance of copper nanoparticles (3 and 7 nm) supported on either silica gel or graphitic carbon is discussed in the selective hydrogenation of 1,3-butadiene in the presence of a 100-fold excess of propene. We demonstrate that the routinely used temperature ramp-up method is not suitable in this case to reliably measure catalyst activity, and we present an alternative measurement method. The catalysts exhibited selectivity to butenes as high as 99% at nearly complete 1,3-butadiene conversion (95%). Kinetic analysis showed that the high selectivity can be explained by considering H2 activation as the rate-limiting step and the occurrence of a strong adsorption of 1,3-butadiene with respect to mono-olefins on the Cu surface. The 7 nm Cu nanoparticles on SiO2 were found to be a very stable catalyst, with almost full retention of its initial activity over 60 h of time on stream at 140 °C. This remarkable long-term stability and high selectivity toward alkenes indicate that Cu nanoparticles are a promising alternative to replace precious-metal-based catalysts in selective hydrogenation.

A novel N-doped graphene oxide enfolded reduced titania for highly stable and selective gas-phase photocatalytic CO2 reduction into CH4: An in-depth study on the interfacial charge transfer mechanism

A desire for renewable alternatives to fossil fuels can be achieved by utilizing CO2, H2O, and solar energy to generate solar fuels. A novel N-doped graphene oxide enfolded reduced titania (NGO-RT) composite was demonstrated for photocatalytic CO2 reduction into CH4. Later, a small amount of Pt NPs was deposited on NGO-RT that increases the catalytic performance towards CH4 formation. The optimized Pt1.0%-NGO-RT catalyst displayed a selective visible-light CO2 reduction into CH4 using a flow reactor system with ≈12 and ≈2 times higher activity than pristine RT and NGO-RT, respectively. The catalyst demonstrated long-term stability over 35 h. The photo-induced CO2 reduction mechanism was first validated through the electron transfer process, where charge trapping by Ti3+ states near the conduction band of RT plays a vital role in the selective CH4 evolution. These trapped electrons transfer from RT to the closely connected interface of N-doped graphene oxide and Pt NPs to restrict the recombination of electron/hole pair. The improved catalytic performance can be attributed to RT’s downward band bending at the NGO-RT interface, where electron transfer from RT to NGO decreases the charge recombination.

Zn-Promoted Selective Gas-Phase Hydrogenation of Tertiary and Secondary C4 Alkynols over Supported Pd.

We have investigated the gas-phase (P = 1 atm; T = 373 K) hydrogenation of (tertiary alkynol) 2-methyl-3-butyn-2-ol (MBY) and (secondary) 3-butyn-2-ol (BY) over a series of carbon (C), non-reducible (Al2O3 and MgO), and reducible (CeO2 and ZnO) supported monometallic [Pd (0.6-1.2% wt) and Zn (1% wt)] and bimetallic Pd-Zn (Pd:Zn mol ratio = 95:5, 70:30, and 30:70) catalysts synthesized by deposition-precipitation and colloidal deposition. The catalysts have been characterized by H2 chemisorption, hydrogen temperature-programmed desorption (H2-TPD), specific surface area (SSA), X-ray photoelectron spectroscopy (XPS), and transmission (TEM) and scanning transmission electron microscopy (STEM) analyses. Reaction over these catalysts generated the target alkenol [2-methyl-3-buten-2-ol (MBE) and 3-buten-2-ol (BE)] through partial hydrogenation and alkanol [2-methyl-butan-2-ol (MBA) and 2-butanol (BA)]/ketone [2-butanone (BONE)] as a result of full hydrogenation and double-bond migration. The catalysts exhibit a similar Pd nanoparticle size (2.7 ± 0.3 nm) but a modified electronic character (based on XPS). Hydrogenation activity is linked to surface hydrogen (from H2 chemisorption and H2-TPD). An increase in H2:alkynol (from 1 → 10) results in enhanced alkynol consumption with a greater rate in the transformation of MBY (vs BY); H2:alkynol had negligible effect on product distribution. Reaction selectivity is insensitive to the Pd site electron density with a similar response (SMBE = 65 ± 9% and SBE = 70 ± 8%) over Pdδ- (on Al2O3 and MgO) and Pdδ+ (on C and CeO2). A Pd/ZnO catalyst delivered enhanced alkenol selectivity (SMBE = 90% and SBE = 96%) attributed to PdZn alloy phase formation (proved by XRD and XPS) but low activity, ascribed to metal encapsulation. A two-fold increase in the consumption rate was recorded for Pd-Zn/Al2O3 (30:70) versus Pd/ZnO with a similar alloy content (32 ± 4% from XPS), ascribed to a contribution due to spillover hydrogen (from H2-TPD) where high alkenol selectivity was maintained.

The consequences of support identity on the oxidative conversion of furfural to maleic anhydride on vanadia catalysts

Maleic anhydride (MA) is a high value building block molecule whose synthesis from furfural (FUR) is proposed as a green and sustainable alternative. In this work, vanadia supported on SiO2, γ-Al2O3, ZrO2 and TiO2 catalysts were synthetized, characterized and investigated for the selective gas phase oxidation of FUR to MA. The catalytic properties depend on both, the nature of the support and the vanadia surface dispersion. V2O5/SiO2 and V2O5/γ-Al2O3 display ca. 50 % MA yield. Conversely, for the V2O5/ZrO2 and V2O5/TiO2 catalysts, complete FUR oxidation to CO2 and negligible MA production was obtained. By decreasing the oxidation potential of the reaction feed, V2O5/ZrO2 and V2O5/TiO2 catalysts achieve MA yields comparable to V2O5/SiO2 and V2O5/γ-Al2O3 catalysts. This behavior is attributed to the higher vanadia dispersion on ZrO2 and TiO2 and the reducible nature of these supports. The results obtained in this work offer new catalytic alternatives for the sustainable production of MA.