Unsaturated Aldehydes Research Articles

NiBi intermetallic compounds catalyst toward selective hydrogenation of unsaturated aldehydes

Intermetallic compounds (IMCs) have evoked considerable attention as high-selectivity catalysts in chemical processes by virtue of their exceptional structural properties. Here we report a general method to obtain Ni-based IMCs via structural transformation from layered double hydroxides (LDHs) precursor, which exhibit excellent selectivity toward CO hydrogenation in various unsaturated aldehydes (crotonaldehyde, 3-methyl-2-butenal, 2-pentenal, furfural, 5-hydroxymethylfurfural and cinnamaldehyde). The optimal catalyst (NiBi IMCs) displays surprisingly high selectivity toward unsaturated alcohols (97.2%, 93.2%, 94.5%, 97.7%, 97.9% and 98.9%, respectively). A combination investigation based on STEM, XANES, and in situ COIR verifies a rugged and ordered surface atomic structure, due to the huge difference in atomic radius between Ni and Bi. Both experiment characterization (in situ FT-IR) and theory calculation (DFT) reveal that the well-organized surface atomic arrangement with a steric hindering effect gives rise to the vertical adsorption configuration of unsaturated aldehydes, resulting in selective hydrogenation of CO instead of CC group. This work shows a significant paradigm for investigation of LDHs-based IMCs catalyst via a deep viewpoint on structure-selectivity relationship, which is potentially applied as a hopeful candidate in heterogeneous hydrogenation catalysis.

Ion transport mechanisms for smoke inhalation-injured airway epithelial barrier.

Smoke inhalation injury is the leading cause of death in firefighters and victims. Inhaled hot air and toxic smoke are the predominant hazards to the respiratory epithelium. We aimed to analyze the effects of thermal stress and smoke aldehyde on the permeability of the airway epithelial barrier. Transepithelial resistance (RTE) and short-circuit current (ISC) of mouse tracheal epithelial monolayers were digitized by an Ussing chamber setup. Zonula occludens-1 tight junctions were visualized under confocal microscopy. A cell viability test and fluorescein isothiocyanate-dextran assay were performed. Thermal stress (40°C) decreased RTE in a two-phase manner. Meanwhile, thermal stress increased ISC followed by its decline. Na+ depletion, amiloride (an inhibitor for epithelial Na+ channels [ENaCs]), ouabain (a blocker for Na+/K+-ATPase), and CFTRinh-172 (a blocker of cystic fibrosis transmembrane regulator [CFTR]) altered the responses of RTE and ISC to thermal stress. Steady-state 40°C increased activity of ENaCs, Na+/K+-ATPase, and CFTR. Acrolein, one of the main oxidative unsaturated aldehydes in fire smoke, eliminated RTE and ISC. Na+ depletion, amiloride, ouabain, and CFTRinh-172 suppressed acrolein-sensitive ISC, but showed activating effects on acrolein-sensitive RTE. Thermal stress or acrolein disrupted zonula occludens-1 tight junctions, increased fluorescein isothiocyanate-dextran permeability but did not cause cell death or detachment. The synergistic effects of thermal stress and acrolein exacerbated the damage to monolayers. In conclusion, the paracellular pathway mediated by the tight junctions and the transcellular pathway mediated by active and passive ion transport pathways contribute to impairment of the airway epithelial barrier caused by thermal stress and acrolein. Graphical abstract Thermal stress and acrolein are two essential determinants for smoke inhalation injury, impairing airway epithelial barrier. Transcellular ion transport pathways via the ENaC, CFTR, and Na/K-ATPase are interrupted by both thermal stress and acrolein, one of the most potent smoke toxins. Heat and acrolein damage the integrity of the airway epithelium through suppressing and relocating the tight junctions.

Regulation of Spermine Oxidase through Hypoxia-Inducible Factor-1α Signaling in Retinal Glial Cells under Hypoxic Conditions.

PurposeAcrolein, a highly reactive unsaturated aldehyde, is known to facilitate glial cell migration, one of the pathological hallmarks in diabetic retinopathy. However, cellular mechanisms of acrolein generation in retinal glial cells remains elusive. In the present study, we investigated the role and regulation of spermine oxidase (SMOX), one of the enzymes related to acrolein generation, in retinal glial cells under hypoxic condition.MethodsImmunofluorescence staining for SMOX was performed using sections of fibrovascular tissues obtained from patients with proliferative diabetic retinopathy. Expression levels of polyamine oxidation enzymes including SMOX were analyzed in rat retinal Müller cell line 5 (TR-MUL5) cells under either normoxic or hypoxic conditions. The transcriptional activity of Smox in TR-MUL5 cells was evaluated using the luciferase assay. Levels of acrolein-conjugated protein, Nε-(3-formyl-3,4-dehydropiperidino) lysine adduct (FDP-Lys), and hydrogen peroxide were measured.ResultsSMOX was localized in glial cells in fibrovascular tissues. Hypoxia induced SMOX production in TR-MUL5 cells, which was suppressed by silencing of hypoxia-inducible factor-1α (Hif1a), but not Hif2a. Transcriptional activity of Smox was regulated through HIF-1 binding to hypoxia response elements 2, 3, and 4 sites in the promoter region of Smox. Generation of FDP-Lys and hydrogen peroxide increased in TR-MUL5 cells under hypoxic condition, which was abrogated by SMOX inhibitor MDL72527.ConclusionsThe current data demonstrated that hypoxia regulates production of SMOX, which plays a role in the generation of oxidative stress inducers, through HIF-1α signaling in Müller glial cells under hypoxic condition.

Sensory, olfactometric and chemical characterization of the aroma potential of Garnacha and Tempranillo winemaking grapes.

Reconstituted polyphenolic and aromatic fractions (PAFs) from 33 different Garnacha and Tempranillo grapes were incubated in strict anoxia (75°C×24h). Obtained hydrolyzates were characterized by sensory analysis, gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). Five different aroma categories emerged. Garnacha may develop specific tropical/citrus fruit, kerosene and floral and Tempranillo toasty-woody and red-fruit characteristics. Those notes seem to mask alcoholic and fruit-in-syrup descriptors and the common vegetal background. Twenty-seven odorants were detected by GC-O. GC-MS data showed a clustering closely matching the one found by sensory analysis, suggesting the existence of five specific metabolomic profiles behind the five specific sensory profiles. Overall results suggest that 3-mercaptohexanol is responsible for tropical/citrus fruit, TDN for kerosene, volatile phenols for woody/toasty, β-damascenone and massoia lactone, likely with Z-1,5-octadien-3-one for fruit-in-syrup and alcoholic notes. Nine lipid-derived unsaturated aldehydes and ketones may be responsible for the vegetal background.

Performant Au hydrogenation catalyst cooperated with Cu-doped Al2O3 for selective conversion of furfural to furfuryl alcohol at ambient pressure

Catalytic hydrogenation of furfural to furfuryl alcohol is an important upgrading process for valorization of biomass-derived furanyl platform molecules. However, selective hydrogenation of α,β-unsaturated aldehydes like furfural to the corresponding alcohols at ambient pressure remains challenging in sustainable chemistry. Till date heterogeneous Au hydrogenation catalyst has been scarcely reported for this reaction due to the low reactivity of Au for H2 dissociation. In this work, we showed that Au nanoparticles (loading: 0.2 wt%) with a mean size of about 3 nm supported on Cu-doped Al2O3 can efficiently hydrogenate furfural to furfuryl alcohol in liquid phase at ambient pressure. We demonstrated that doping a small amount of Cu (2 mol%) to γ-Al2O3 may modify the Lewis acidity-basicity of Al2O3 and simultaneously induce the presence of sufficient Cu+ species on surface, which facilitated the hydrogen transfer from i-PrOH to furfural. Moreover, we observed an enhanced reactivity of Au toward molecular H2via cooperation with the Lewis acidic-basic Cu2O-Al2O3 support. Hence, 100% yield to furfuryl alcohol with a productivity of 0.98 gFA⋅h−1⋅gcat.−1 at 120 °C and 0.1 MPa H2 can be obtained. The prepared Au/Cu-Al2O3 catalyst was found reusable and was effective to the concentrated furfural solution, as well as several typical unsaturated aldehydes.

Acrolein Aggravates Secondary Brain Injury After Intracerebral Hemorrhage Through Drp1-Mediated Mitochondrial Oxidative Damage in Mice

Clinical advances in the treatment of intracranial hemorrhage (ICH) are restricted by the incomplete understanding of the molecular mechanisms contributing to secondary brain injury. Acrolein is a highly active unsaturated aldehyde which has been implicated in many nervous system diseases. Our results indicated a significant increase in the level of acrolein after ICH in mouse brain. In primary neurons, acrolein induced an increase in mitochondrial fragmentation, loss of mitochondrial membrane potential, generation of reactive oxidative species, and release of mitochondrial cytochrome c. Mechanistically, acrolein facilitated the translocation of dynamin-related protein1 (Drp1) from the cytoplasm onto the mitochondrial membrane and led to excessive mitochondrial fission. Further studies found that treatment with hydralazine (an acrolein scavenger) significantly reversed Drp1 translocation and the morphological damage of mitochondria after ICH. In parallel, the neural apoptosis, brain edema, and neurological functional deficits induced by ICH were also remarkably alleviated. In conclusion, our results identify acrolein as an important contributor to the secondary brain injury following ICH. Meanwhile, we uncovered a novel mechanism by which Drp1-mediated mitochondrial oxidative damage is involved in acrolein-induced brain injury.

Derailed Ohira‐Bestmann Reaction of γ,δ‐Unsaturated Aldehydes for the Stereoselective Synthesis of Cyclopenta[c]pyrazoles

AbstractThe synthesis of cyclopenta[c]pyrazoles from γ,δ‐unsaturated aldehydes by a domino sequence involving one‐carbon homologation and intramolecular azomethine imine 1,3‐dipolar cycloaddition is disclosed. The fused pyrazoles bearing aromatic and aliphatic substituents are obtained in good yields and excellent diastereomeric purity. Additionally, the synthetic utility of the pyrazole products generated by this method has been highlighted in a series of functionalization reactions. The method presented opens strategic opportunities for the synthesis of pyrazole‐containing biologically active compounds.

Identification of C9-C11 unsaturated aldehydes as prediction markers of growth and feed intake for non-ruminant animals fed oxidized soybean oil

BackgroundThe benefits of using the oxidized oils from rendering and recycling as an economic source of lipids and energy in animal feed always coexist with the concerns that diverse degradation products in these oxidized oils can negatively affect animal health and performance. Therefore, the quality markers that predict growth performance could be useful when feeding oxidized oils to non-ruminants. However, the correlations between growth performance and chemical profiles of oxidized oils have not been well examined. In this study, six thermally oxidized soybean oils (OSOs) with a wide range of quality measures were prepared under different processing temperatures and processing durations, including 45 °C-336 h; 67.5 °C-168 h; 90 °C-84 h; 135 °C-42 h; 180 °C-21 h; and 225 °C-10.5 h. Broilers and nursery pigs were randomly assigned to diets containing either unheated control soybean oil or one of six OSOs. Animal performance was determined by measuring body weight gain, feed intake, and gain to feed ratio. The chemical profiles of OSOs were first evaluated by common indicative tests, including peroxide value, thiobarbituric acid reactive substances, p-anisidine value, free fatty acids, oxidized fatty acids, unsaponifiable matter, insoluble impurities, and moisture, and then analyzed by the liquid chromatography-mass spectrometry-based chemometric analysis.ResultsAmong common quality indicators, p-anisidine value (AnV), which reflects the level of carbonyl compounds, had the greatest inverse correlation with the growth performance of both broilers and pigs, followed by free fatty acids and oxidized fatty acids. Among the 17 aldehydes identified in OSOs, C9-C11 alkenals, especially 2-decenal and 2-undecenal, had stronger inverse correlations (r < − 0.8) with animal performance compared to C5-C8 saturated alkanals, suggesting that chain length and unsaturation level affect the toxicity of aldehydes.ConclusionsAs the major lipid oxidation products contributing to the AnV, individual C9-C11 unsaturated aldehydes in heavily-oxidized oils could function as effective prediction markers of growth and feed intake in feeding non-ruminants.

Description of Druglike Properties of Safranal and Its Chemistry behind Low Oral Exposure.

Safranal, a plant secondary metabolite isolated from saffron, has been reported for several promising pharmacological properties toward the management of Alzheimer’s disease. In the present study, we observe and report for the first time about several druglike attributes of safranal, such as adherence to Lipinski’s rule of five; optimum lipophilicity; high permeability; low blood-to-plasma ratio; less to moderate propensity to interact with P-glycoprotein (P-gp) or breast cancer-resistant protein (BCRP) transporters; and high plasma protein binding as common to most of the marketed drugs using in vitro and ex vivo models. In spite of the above attributes, in vivo oral absorption was found to be very poor, which is linked to the structural integrity of safranal in simulated gastric fluid, simulated intestinal fluid, plasma, and liver microsomes. Moreover, the presence of unsaturated aldehyde moiety in safranal remains in equilibrium with its hydroxylated acetal form. Further research work is required to find out the stable oral absorbable form of safranal by derivatization of its aldehyde group without losing its potency.

Microenvironment of MOF Channel Coordination with Pt NPs for Selective Hydrogenation of Unsaturated Aldehydes

Surface and interface states of noble metal nanoparticles (MNPs), closely related to the catalytic performance, have been of great concern to academics in the field of catalysis. The catalytic prop...

Mechanistic studies of inhibition on acrolein by myricetin

Acrolein (ACR) is an unsaturated aldehyde with high activity and toxicity and is produced in vivo and in food. This study investigated the impact of B-ring structure on the trapping of ACR by flavonols and the trapping mechanism and efficacy of ACR by myricetin. Galangin, kaempferol, quercetin, and myricetin, which possess the same A- and C-ring but different numbers of –OH groups on the B-ring, were selected for this study. Our results suggested that increasing the number of –OH groups on the B-ring can enhance the ACR trapping efficacy of flavonol and myrectin was identified as the most active flavonol. The adducts of myricetin with ACR under different ratios and incubation times were analyzed using LC-MS/MS. We also purified and identified the major mono- and di-ACR-myricetin adducts. Furthermore, myricetin could dose-dependently inhibit the formation of ACR in cookies through the formation of mono- and di-ACR adducts.

Synthesis of novel hybrid quinolino[4,3-b][1,5]naphthyridines and quinolino[4,3-b][1,5]naphthyridin-6(5H)-one derivatives and biological evaluation as topoisomerase I inhibitors and antiproliferatives

The topoisomerase I enzymatic inhibition of hybrid quinolino [4,3-b] (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridines and quinolino [4,3-b] (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridin-6(5H)-ones was investigated. First, the synthesis of these fused compounds was performed by intramolecular [4 + 2]-cycloaddition reaction of functionalized aldimines obtained by the condensation of 3-aminopyridine and unsaturated aldehydes affording corresponding hybrid 5-tosylhexahydroquinolino [4,3-b] (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridine and tetrahydroquinolino [4,3-b] (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridin-6(5H)-one compounds with good to high general yields. Subsequent dehydrogenation led to the corresponding more unsaturated dihydro (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridine and (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridin-6(5H)-one derivatives in quantitative yields. The new polycyclic products show excellent-good activity as topoisomerase I (TopI) inhibitors that lead to TopI induced nicking of plasmids. This is consistent with the compounds acting as TopI poisons resulting in the accumulation of trapped cleavage complexes in the DNA. The cytotoxic effect on cell lines A549, SKOV3 and on non-cancerous MRC5 was also screened. Tetrahydroquinolino [4,3-b] (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridin-6(5H)-one 9 resulted the most cytotoxic compound with IC50 values of 3.25 ± 0.91 μM and 2.08 ± 1.89 μM against the A549 cell line and the SKOV3 cell line, respectively. Also, hexahydroquinolino [4,3-b] (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridine 8a and dihydroquinolino [4,3-b] (Siegel et al., 2013; Antony et al., 2003) [1,5]naphthyridine 10a showed good cytotoxicity against these cell lines. None of the compounds presented cytotoxic effects against non-malignant pulmonary fibroblasts (MRC-5).

Comparison and study on the asymmetric uranyl—salophen to the single carbonyl molecules

Theoretical study of the asymmetric uranyl−salophen (AUS) on the unsaturated aldehyde or ketone is a focus of present research. This study underlines the complexes of asymmetric uranyl−salophen (as modified by unilateral benzene) to single carbonyl molecules, including formaldehyde, acetone, cyclopentanone, and cyclohexanone, using the density functional theory of quantum chemistry. Our results suggest that the C=O double bond of the single carbonyl molecules is weakened by the asymmetric uranyl−salophen. Both the negative charge of oxygen atoms and the positive charge of carbon atoms from the C=O bond of the single carbonyl have increased, and the binding energies and stability between asymmetric uranyl−salophen and acetone, cyclopentanone, or cyclohexanone were higher than that of formaldehyde. These new findings could be used as an important reference for the study of other complexes that the asymmetric uranyl−salophen to the complex carbonyl molecules.

Mechanism of Acrolein Toxicity:The Effect on Epigenetic Changes

Acrolein, an alpha‐beta unsaturated aldehyde and a very reactive toxic compound, is released into the environment from different sources such as combustion of fossil fuel, cigarette smoke, overheating of frying oil, as well as endogenously being produced in body via lipid peroxidation. As a pervasive environmental pollutant, acrolein poses a serious environmental health threat acknowledged by investigators, health, and environmental government agencies.Epigenetics is the modifications in gene expression that do not alter the DNA sequence of a gene. This alteration could occur naturally or by factors such as age, environmental exposure, individual lifestyle, and disease condition. Phosphorylation, Methylations and acetylation are the most common epigenetic changes. N‐ Acetyl cysteine (NAC) is an antioxidant involved in the production of cellular glutathione.The aim of the study was to determine the effect of acrolein on histone phosphorylation, acetylation and methylation in vascular smooth muscle cells (VSMCs) and to establish the beneficial effect of NAC in prevention of acrolein toxicity through blockage of histones modification.VSMCs were treated with 3μg/ml acrolein for 6 hours in the presence and absence of 0.2 mM NAC. At the end of the treatment, cytotoxicity of acrolein was measured using tetrazolium‐calorimetric assay. Additionally, free radical generation was measured by fluorometric methods, histone H3 modification by ELISA kit, and protein expression by western blotting.Results indicated that six‐hour exposure of VSMC to 3μg/ml of acrolein resulted in 99% decrease in cell viability and addition of 0.2Mm of NAC provided complete protection of VSMCs from toxicity caused by acrolein. In the absence of NAC, acrolein increased level of reactive oxygen species (ROS) generation by 85%. Addition of NAC abolished high level of ROS by 75%.ELISA analysis showed acrolein‐induced modification of histones 3 (H3) at different lysine and serine residues including SER‐10P and SER‐28P, K4ME, K9ME, K27ME, K79ME, K9AC, K14AC, K18AC. Western blot analysis of two of these residues indicated 45% increase in Ser10P1, 59% increase in Ser28p1, and addition of NAC decreased these modifications by 86% and 76% respectively. Additionally, we observed a 66% increase in the expression of methylated H3K9 and 66% in acetylated H3k9 protein, which was attenuated by addition of NAC by 71% and 65% respectively.In conclusion, this study revealed that exposure of VSMCs to acrolein causes modification of H3 histones at different residues and NAC is effective in inhibiting the effects of acrolein.Support or Funding InformationNIH SC3GM103746‐04

Importance of isomerization reactions for OH radical regeneration from the photo-oxidation of isoprene investigated in the atmospheric simulation chamber SAPHIR

Abstract. Theoretical, laboratory, and chamber studies have shown fast regeneration of the hydroxyl radical (OH) in the photochemistry of isoprene, largely due to unimolecular reactions which were previously thought not to be important under atmospheric conditions. Based on early field measurements, nearly complete regeneration was hypothesized for a wide range of tropospheric conditions, including areas such as the rainforest where slow regeneration of OH radicals is expected due to low concentrations of nitric oxide (NO). In this work the OH regeneration in isoprene oxidation is directly quantified for the first time through experiments covering a wide range of atmospherically relevant NO levels (between 0.15 and 2 ppbv – parts per billion by volume) in the atmospheric simulation chamber SAPHIR. These conditions cover remote areas partially influenced by anthropogenic NO emissions, giving a regeneration efficiency of OH close to 1, and areas like the Amazonian rainforest with very low NO, resulting in a surprisingly high regeneration efficiency of 0.5, i.e. a factor of 2 to 3 higher than explainable in the absence of unimolecular reactions. The measured radical concentrations were compared to model calculations, and the best agreement was observed when at least 50 % of the total loss of isoprene peroxy radicals conformers (weighted by their abundance) occurs via isomerization reactions for NO lower than 0.2 ppbv. For these levels of NO, up to 50 % of the OH radicals are regenerated from the products of the 1,6 α-hydroxy-hydrogen shift (1,6-H shift) of Z-δ-RO2 radicals through the photolysis of an unsaturated hydroperoxy aldehyde (HPALD) and/or through the fast aldehydic hydrogen shift (rate constant ∼10 s−1 at 300 K) in di-hydroperoxy carbonyl peroxy radicals (di-HPCARP-RO2), depending on their relative yield. The agreement between all measured and modelled trace gases (hydroxyl, hydroperoxy, and organic peroxy radicals, carbon monoxide, and the sum of methyl vinyl ketone, methacrolein, and hydroxyl hydroperoxides) is nearly independent of the adopted yield of HPALD and di-HPCARP-RO2 as both degrade relatively fast (&lt;1 h), forming the OH radical and CO among other products. Taking into consideration this and earlier isoprene studies, considerable uncertainties remain on the distribution of oxygenated products, which affect radical levels and organic aerosol downwind of unpolluted isoprene-dominated regions.

Scientific Opinion on Flavouring Group Evaluation 72, Revision 2 (FGE.72Rev2): consideration of aliphatic, branched-chain saturated and unsaturated alcohols, aldehydes, acids and related esters evaluated by JECFA (61st, 68th and 69th meetings) and structurally related to flavouring substances in FGE.05Rev3.

The EFSA Panel on Food Additives and Flavourings was requested to evaluate 31 flavouring substances assigned to the Flavouring Group Evaluation 72 (FGE.72), using the Procedure as outlined in the Commission Regulation (EC) No 1565/2000. Twenty‐three substances have already been considered in FGE.72 and FGE.72Rev1 ([FL‐no: 02.011, 02.012, 02.027, 02.029, 02.058, 02.076, 02.109, 05.020, 05.021, 05.124, 05.148, 05.169, 08.036, 08.044, 08.047, 08.055, 08.064, 08.070, 08.079, 09.273, 09.408, 09.931 and 16.001]). The remaining eight flavouring substances have been cleared with respect to genotoxicity in FGE.200Rev1 ([FL‐no: 05.114]) and FGE.201Rev2 ([FL‐no: 02.174, 05.033, 05.090, 05.095, 05.105, 05.107 and 05.126]) and they are considered in this revision 2 of FGE.72. The substances were evaluated through a stepwise approach that integrates information on the structure–activity relationships, intake from current uses, toxicological threshold of concern (TTC), and available data on metabolism and toxicity. The Panel concluded that none of these 31 substances gives rise to safety concerns at their levels of dietary intake, estimated on the basis of the ‘Maximised Survey‐derived Daily Intake’ (MSDI) approach. Besides the safety assessment of the flavouring substances, the specifications for the materials of commerce have also been considered and found adequate for all 31 flavouring substances. For 21 substances, evaluated through the Procedure in the previous revision (FGE.72Rev1), no normal and maximum use levels are available. For four substances, the modified Theoretical Added Maximum Daily Intake (mTAMDI) intake estimates are equal to ([FL‐no: 05.090]) or above ([FL‐no: 05.107, 05.105, 05.033]) the TTC for their structural class. Therefore, for these 25 substances more detailed data on uses and use levels should be provided in order to refine their exposure assessments and to finalise their safety evaluations.

Effects of Sn&lt;i&gt;&lt;sub&gt;x&lt;/sub&gt;&lt;/i&gt;Pt&lt;i&gt;&lt;sub&gt;y&lt;/sub&gt;&lt;/i&gt; Alloy Structures on the Performance of SnPt Catalysts for the Selective Hydrogenation of Unsaturated Aldehydes to Unsaturated Alcohols

Effects of Sn&lt;i&gt;&lt;sub&gt;x&lt;/sub&gt;&lt;/i&gt;Pt&lt;i&gt;&lt;sub&gt;y&lt;/sub&gt;&lt;/i&gt; Alloy Structures on the Performance of SnPt Catalysts for the Selective Hydrogenation of Unsaturated Aldehydes to Unsaturated Alcohols

Kinetic Study of the Hydrogenation of Unsaturated Aldehydes Promoted by CuPtx/SBA-15 Single-Atom Alloy (SAA) Catalysts

A comprehensive study of the kinetics of the catalytic hydrogenation of unsaturated aldehydes, in particular of cinnamaldehyde, promoted by CuPtx/SBA-15 single-atom alloy catalysts was carried out ...

Asymmetric Synthesis of Rugulotrosin A

A new approach was developed to construct the tetrahydroxanthone by a Knoevenagel condensation/6π-electronic cyclization/aromatization cascade starting from readily available cyclohexane-1,3-diones and unsaturated aldehydes. This strategy provides a new solution for the preparation of monomeric tetrahydroxanthones bearing different functional groups at C-12. As a synthetic application, the asymmetric formal synthesis of rugulotrosin A was achieved.

Highly Selective Catalysts for the Hydrogenation of Unsaturated Aldehydes: A Review

The selective hydrogenation of unsaturated aldehydes (UAL) to saturated aldehydes (SAL) and unsaturated alcohols (UOL) is an important industrial process for producing fine chemicals. More efforts ...