Gluten-free diet adherence in pediatric celiac patients: Evaluating CDAT questionnaire and test for gluten detection in urine.

OBJECTIVES: This study aimed to evaluate the contributions of the Adapted Celiac Dietary Adherence Test (CDAT) and the Rapid Urinary Gluten Detection Test (u-GIP) in assessing gluten-free diet adherence in children and adolescents with celiac disease. METHODS: Fifty-four celiac patients from two pediatric gastroenterology outpatient clinics affiliated with university hospitals were evaluated. The original CDAT was adapted for children through a transcultural process, and the original cutoff point was adopted to define adherence. A single examiner carried out the u-GIP test in fresh urine samples. Sociodemographic and clinical factors and family food security status were also evaluated. RESULTS: A total of 88.9% of participants (confidence interval [CI]: 77.4-95.8; p<0.001) adhered to the gluten-free diet, as determined by the adapted CDAT score, while 87.0% (CI: 75.1-94.6; p<0.001) had negative u-GIP results. Among the 48 children adhering to the CDAT, six exhibited positive u-GIP results in a urine sample. Of the six nonadherent participants, only one had a positive u-GIP result. Notably, none of the children and adolescents with celiac disease who tested positive for u-GIP reported symptoms on the day of testing, and their growth rates remained stable. CONCLUSIONS: Even celiac children and adolescents adhering to the CDAT questionnaire may show a positive u-GIP in a single measurement without accompanying symptoms or growth impairment. The u-GIP could be helpful in complementary tests in specific situations, such as for patients who exhibit compliant behavior but still experience symptoms or maintain persistent positive serology.

Vomiting and Gastric Motility in Early Brain Damaged Children With Congenital Zika Syndrome.

OBJECTIVES: This study investigated the occurrence of vomiting and gastric dysmotility in dysphagic children with congenital Zika syndrome (CZS) and assessed possible associations of these findings with the severity of dysphagia and the presence of tube feeding. METHODS: Forty-six children with CZS were assessed for dysphagia, and the occurrence of vomiting, dietary volume tolerance <15 mL/kg, and feeding time per meal >30 minutes were evaluated. Gastric antrum ultrasonography was used to detect the frequency of contractions and measure antral areas (at fasting and 15 minutes postprandial), from which the gastric emptying rate (GER) was calculated. Antral ultrasonography findings were compared with those of ten healthy controls. Vomiting and gastric motility were compared between CZS patients according to the severity of dysphagia and the requirement for tube feeding. RESULTS: Overall, 76% (35/46) of children with CZS had moderate-to-severe dysphagia (MSD), among whom 60% (21/35) were tube fed [MSD tube fed (MSDTF)]. Vomiting occurred in 54% (25/46) of children, whereas dietary volume intolerance and prolonged feeding time were observed in 59% (27/46) and 37% (17/46), respectively, most frequently in MSDTF patients. On ultrasound, 61% (28/46) of children with CZS had no antral contractions, whereas 90% (9/10) of controls did. Compared to healthy controls, GER was eight-fold lower in children with CZS and 60-fold lower in MSDTF children. CONCLUSIONS: In dysphagic children with CZS, vomiting, volume intolerance, and prolonged feeding time were frequent and possibly associated with impaired antral contraction and delayed gastric emptying, especially in cases of severe dysphagia and tube feeding.

Catalytic Transfer Hydrogenation and Acid Reactions of Furfural and 5-(Hydroxymethyl)furfural over Hf-TUD-1 Type Catalysts.

Heterogeneous catalysis, which has served well the petrochemical industry, may valuably contribute towards a bio-based economy by sustainably enabling selective reactions to renewable chemicals. Carbohydrate-containing matter may be obtained from various widespread sources and selectively converted to furanic platform chemicals: furfural (Fur) and 5-(hydroxymethyl)furfural (Hmf). Valuable bioproducts may be obtained from these aldehydes via catalytic transfer hydrogenation (CTH) using alcohols as H-donors under relatively moderate reaction conditions. Hafnium-containing TUD-1 type catalysts were the first of ordered mesoporous silicates explored for the conversion of Fur and Hmf via CTH/alcohol strategies. The materials promoted CTH and acid reactions leading to the furanic ethers. The bioproducts spectrum was broader for the reaction of Fur than of Hmf. A Fur reaction mechanism based on literature data was discussed and supported by kinetic modelling. The influence of the Hf loading and reaction conditions (catalyst load, type of alcohol H-donor, temperature, initial substrate concentration) on the reaction kinetics was studied. The reaction conditions were optimized to maximize the yields of 2-(alkoxymethyl)furan ethers formed from Fur; up to 63% yield was reached at 88% Fur conversion, 4 h/150 °C, using Hf-TUD-1(75), which was a stable catalyst. The Hf-TUD-1(x) catalysts promoted the selective conversion of Hmf to bis(2-alkoxymethyl)furan; e.g., 96% selectivity at 98% Hmf conversion, 3 h/170 °C for Hf-TUD-1(50).

Characteristics of Dysphagia in Infants with Microcephaly Caused by Congenital Zika Virus Infection, Brazil, 2015.

We summarize the characteristics of dysphagia in 9 infants in Brazil with microcephaly caused by congenital Zika virus infection. The Schedule for Oral Motor Assessment, fiberoptic endoscopic evaluation of swallowing, and the videofluoroscopic swallowing study were used as noninstrumental and instrumental assessments. All infants had a degree of neurologic damage and showed abnormalities in the oral phase. Of the 9 infants, 8 lacked oral and upper respiratory tract sensitivity, leading to delays in initiation of the pharyngeal phase of swallowing. Those delays, combined with marked oral dysfunction, increased the risk for aspiration of food, particularly liquid foods. Dysphagia resulting from congenital Zika virus syndrome microcephaly can develop in infants >3 months of age and is severe.

Robust Multifunctional Yttrium-Based Metal-Organic Frameworks with Breathing Effect.

Phosphonate- and yttrium-based metal-organic frameworks (MOFs), formulated as [Y(H5btp)]·5.5H2O (1), [Y(H5btp)]·2.5H2O (2), (H3O)[Y2(H5btp)(H4btp)]·H2O (3), and [Y(H5btp)]·H2O·0.5(MeOH) (4), were prepared using a "green" microwave-assisted synthesis methodology which promoted the self-assembly of the tetraphosphonic organic linker [1,1'-biphenyl]-3,3',5,5'-tetrayltetrakis(phosphonic acid) (H8btp) with Y3+ cations. This new family of functional materials, isolated in bulk quantities, exhibits a remarkable breathing effect. Structural flexibility was thoroughly studied by means of X-ray crystallography, thermogravimetry, variable-temperature X-ray diffraction, and dehydration and rehydration processes, ultimately evidencing a remarkable reversible single-crystal to single-crystal (SC-SC) transformation solely through the loss and gain of crystallization solvent molecules. Topologically, frameworks remained unaltered throughout this interconversion mechanism, with all compounds being binodal 6,6-connected network with a Schäfli symbol of {413.62}{48.66.8}. Results show that this is one of the most stable and thermally robust families of tetraphosphonate-based MOFs synthesized reported to date. Porous materials 2 and 3 were further studied to ascertain their performance as heterogeneous catalysts and proton conductors, respectively, with outstanding results being registered for both materials. Compound 2 showed a 94% conversion of benzaldehyde into (dimethoxymethyl)benzene after just 1 h of reaction, among the best results registered to date for MOF materials. On the other hand, the protonic conductivity of compound 3 at 98% of relative humidity (2.58 × 10-2 S cm-1) was among the highest registered among MOFs, with the great advantage of the material to be prepared using a simpler and sustainable synthesis methodology, as well as exhibiting a good stability at ambient conditions (temperature and humidity) over time when compared to others.

A Lamellar Coordination Polymer with Remarkable Catalytic Activity.

A positively charged lamellar coordination polymer based on a flexible triphosphonic acid linker is reported. [Gd(H4 nmp)(H2 O)2 ]Cl⋅2 H2 O (1) [H6 nmp=nitrilotris(methylenephosphonic acid)] was obtained by a one-pot approach by using water as a green solvent and by forcing the inclusion of additional acid sites by employing HCl in the synthesis. Compound 1 acts as a versatile heterogeneous acid catalyst with outstanding activity in organic reactions such as alcoholysis of styrene oxide, acetalization of benzaldehyde and cyclohexanaldehyde and ketalization of cyclohexanone. For all reaction systems, very high conversions were reached (92-97 %) in only 15-30 min under mild conditions (35 °C, atmospheric pressure). The coordination polymer exhibits a protonic conductivity of 1.23×10(-5)  S cm(-1) at 98 % relative humidity and 40 °C.

Catalytic alcoholysis of epoxides using metal-free cucurbituril-based solids.

Metal-free cucurbit[7]uril (CB7) solid-state assemblies promote acid-catalysed alcoholysis of aliphatic and aromatic epoxides under mild conditions to give ß-alkoxy alcohols, which are important intermediates for the synthesis of a vast range of compounds such as bioactive pharmaceuticals. The catalytic process is heterogeneous and the catalyst can be reused in consecutive runs without any reactivation treatment. The acid species responsible for the catalytic activity of CB7 may be entrapped hydronium ions.

Crystal Structure and Catalytic Behavior in Olefin Epoxidation of a One-Dimensional Tungsten Oxide/Bipyridine Hybrid.

The tungsten oxide/2,2'-bipyridine hybrid material [WO3(2,2'-bpy)]·nH2O (n = 1-2) (1) has been prepared in near quantitative yield by the reaction of H2WO4, 2,2'-bpy, and H2O in the mole ratio of ca. 1:2:700 at 160 °C for 98 h in a rotating Teflon-lined digestion bomb. The solid-state structure of 1 was solved and refined through Rietveld analysis of high-resolution synchrotron X-ray diffraction data collected for the microcrystalline powder. The material, crystallizing in the orthorhombic space group Iba2, is composed of a one-dimensional organic-inorganic hybrid polymer, ∞(1)[WO3(2,2'-bpy)], topologically identical to that found in the previously reported anhydrous phases [MO3(2,2'-bpy)] (M = Mo, W). While in the latter the N,N'-chelated 2,2'-bpy ligands of adjacent corner-shared {MO4N2} octahedra are positioned on the same side of the 1D chain, in 1 the 2,2'-bpy ligands alternate above and below the chain. The catalytic behavior of compound 1 for the epoxidation of cis-cyclooctene was compared with that for several other tungsten- or molybdenum-based (pre)catalysts, including the hybrid polymer [MoO3(2,2'-bpy)]. While the latter exhibits superior performance when tert-butyl hydroperoxide (TBHP) is used as the oxidant, compound 1 is superior when aqueous hydrogen peroxide is used, allowing near-quantitative conversion of the olefin to the epoxide. With H2O2, compounds 1 and [MoO3(2,2'-bpy)] act as sources of soluble active species, namely, the oxodiperoxo complex [MO(O2)2(2,2'-bpy)], which is formed in situ. Compounds 1 and [WO(O2)2(2,2'-bpy)] (2) were further tested in the epoxidation of cyclododecene, trans-2-octene, 1-octene, (R)-limonene, and styrene. The structure of 2 was determined by single-crystal X-ray diffraction and found to be isotypical with the molybdenum analogue.

Influence of Enteral Nutrition on Occurrences of Necrotizing Enterocolitis in Very-Low-Birth-Weight Infants.

OBJECTIVE: The aim of the present study was to investigate the influence of enteral feeding management on occurrences of necrotizing enterocolitis (NEC) in very-low-birth-weight (VLBW) infants. METHODS: This was a case-control study conducted in a sample of 1028 VLBW infants (750 to 1499 g) admitted to a neonatal intensive care unit between January 2003 and May 2008. "Cases" were infants born with VLBW and diagnosed with NEC within the first 30 days of life, and "controls" were VLBW infants who did not develop NEC during this period. Occurrences of NEC were defined using the modified Bell criteria (stage ≥2). RESULTS: Among the 1028 VLBW infants, 55 (5.4%) developed NEC within the first month of life. Logistic regression analysis showed that breast milk given exclusively for <7 days (odds ratio [OR] = 4.02), never achieving full enteral feeding during the first month (OR = 3.50), and parenteral nutrition (OR = 2.70) were factors that increased the chances of NEC occurrence. The use of vasoactive drugs was associated with a lower risk of NEC (OR = 0.15). CONCLUSIONS: Breast milk should be recommended as a priority for the enteral nutrition of VLBW infants for no <7 days. Enteral nutrition should start early and progress quickly to achieve full enteral feeding; these procedures may help reduce the occurrence of NEC.

Influence of preeclampsia and gestational obesity in maternal and newborn levels of vitamin D.

BACKGROUND: In recent years, a high prevalence of vitamin D deficiency amongst pregnant women and newborns has been observed throughout several regions of the world, especially in the presence of preeclampsia (PE) or obesity (OB). The aim of this study was to investigate whether nonobese and obese preeclamptic pregnant women and their newborns have low 25(OH)D compared with nonobese and obese nonpreeclamptic pregnant women; and to verify whether the maternal level of this vitamin correlates with the newborns' level. METHODS: This is a cross-sectional study conducted with 179 pregnant women recruited immediately before delivery, divided into four groups: PE(+)/OB(-); PE(+)/OB(+); PE(-)/OB(+); and PE(-)/OB(-), with gestational age ≥ 34 weeks. Maternal peripheral blood and newborns umbilical cord blood were collected and 25(OH)D levels were measured by chemiluminescence (LIAISON®). RESULTS: Infants born to preeclamptic mothers had a lower median 25(OH)D level than those born to nonpreeclamptic mothers (p < 0.01). Obese pregnant women and their newborns had higher frequencies of 25(OH)D deficiency, but the difference with respect to nonobese pregnant women and their newborns was not significant. The vitamin D status of preeclamptic obese women was not worse than that of their nonobese counterparts. Newborns and maternal 25(OH)D levels were significantly correlated (p = 0.01). Obesity weakened this correlation. CONCLUSIONS: Preeclamptic women and their newborns presented higher frequencies of 25(OH)D deficiency, but 25(OH)D levels were not significantly influenced by obesity. Obese pregnant women transferred less 25(OH)D to their fetuses.

Single-Step Formation of Metal Oxide Nanostructures Wrapped in Mesoporous Silica and Silica-Niobia Catalysts for the Condensation of Furfural with Acetone.

The integration of metal oxide nanomaterials with mesoporous silica is a promising approach to exploiting the advantages of both types of materials. Traditional synthesis methods typically require multiple steps. This work instead presents a fast, one-step, template-free method for the synthesis of metal oxides homogeneously dispersed within mesoporous silica, including oxides of W, Ti, Nb, Ta, Sn, and Mo. These composites have tunable metal oxide contents, large surface areas, and wide mesopores. The combination of Nb2O5 nanoparticles (NPs) with SiO2 results in an increased surface area and a larger number of acid sites compared to pure Nb2O5 NPs. The surface texture and acidity of the silica-niobia composites can be tuned by adjusting the Nb/Si molar ratio. Moreover, the silica provides protection to the niobia NPs, preventing sintering during thermal treatment at 400 °C. The silica-niobia materials exhibit superior performance as catalysts in the aldol condensation of furfural (Fur) with acetone compared to pure niobia, leading to an up to 62% in product yield. Additionally, these catalysts show remarkable stability, retaining their performance over multiple runs. This work demonstrates the potential of the proposed synthesis approach for preparing more sustainable, high-performance, durable, and stable nanoscale metal oxide-based catalysts with a tunable composition, surface area, and active site density.

Coupling of nanoporous chromium, aluminium-containing silicates with an ionic liquid for the transformation of glucose into 5-(hydroxymethyl)-2-furaldehyde.

Micro/mesoporous chromium, aluminium-containing silicates of the type TUD-1 (Al-TUD-1, Cr-TUD-1, CrAl-TUD-1) and zeolite BEA, Cr-BEA, and related composites BEA/TUD-1 and Cr-BEA/TUD-1, were prepared, characterised, and tested as solid acids coupled with the ionic liquid (IL) 1-butyl-3-methylimidazolium chloride ([bmim]Cl) as solvent, in the transformation of D-glucose into 5-(hydroxymethyl)-2-furaldehyde (Hmf), at 120 °C. The chromium-containing catalytic systems lead to considerably higher Hmf yields in comparison to the related systems without chromium. The IL is a favourable solvent for this target reaction (in terms of Hmf yields reached) compared to water or dimethylsulfoxide. A detailed study on the stabilities of the nanoporous solid acids in the IL medium is presented.

Development of alginate-based hydrogels for blood vessel engineering.

Vascular diseases are among the primary causes of death worldwide. In serious conditions, replacement of the damaged vessel is required. Autologous grafts are preferred, but their limited availability and difficulty of the harvesting procedures favour synthetic alternatives' use. However, as synthetic grafts may present significant drawbacks, tissue engineering-based solutions are proposed. Herein, tubular hydrogels of alginate combined with collagen type I and/or silk fibroin were prepared by ionotropic gelation using gelatin hydrogel sacrificial moulds loaded with calcium ions (Ca2+). The time of exposure of alginate solutions to Ca2+-loaded gelatin was used to control the wall thickness of the hydrogels (0.47 ± 0.10 mm-1.41 ± 0.21 mm). A second crosslinking step with barium chloride prevented their degradation for a 14 day period and improved mechanical properties by two-fold. Protein leaching tests showed that collagen type I, unlike silk fibroin, was strongly incorporated in the hydrogels. The presence of silk fibroin in the alginate matrix, containing or not collagen, did not significantly improve hydrogels' properties. Conversely, hydrogels enriched only with collagen were able to better support EA.hy926 and MRC-5 cells' growth and characteristic phenotype. These results suggest that a two-step crosslinking procedure combined with the use of collagen type I allow for producing freestanding vascular substitutes with tuneable properties in terms of size, shape and wall thickness.

Micro/mesoporous LTL derived materials for catalytic transfer hydrogenation and acid reactions of bio-based levulinic acid and furanics.

The biomass-derived platform chemicals furfural and 5-(hydroxymethyl)furfural (HMF) may be converted to α-angelica lactone (AnL) and levulinic acid (LA). Presently, LA (synthesized from carbohydrates) has several multinational market players. Attractive biobased oxygenated fuel additives, solvents, etc., may be produced from AnL and LA via acid and reduction chemistry, namely alkyl levulinates and γ-valerolactone (GVL). In this work, hierarchical hafnium-containing multifunctional Linde type L (LTL) related zeotypes were prepared via top-down strategies, for the chemical valorization of LA, AnL and HMF via integrated catalytic transfer hydrogenation (CTH) and acid reactions in alcohol medium. This is the first report of CTH applications (in general) of LTL related materials. The influence of the post-synthesis treatments/conditions (desilication, dealumination, solid-state impregnation of Hf or Zr) on the material properties and catalytic performances was studied. AnL and LA were converted to 2-butyl levulinate (2BL) and GVL in high total yields of up to ca. 100%, at 200°C, and GVL/2BL molar ratios up to 10. HMF conversion gave mainly the furanic ethers 5-(sec-butoxymethyl)furfural and 2,5-bis(sec-butoxymethyl)furan (up to 63% total yield, in 2-butanol at 200°C/24 h). Mechanistic, reaction kinetics and material characterization studies indicated that the catalytic results depend on a complex interplay of different factors (material properties, type of substrate). The recovered-reused solids performed steadily.

Physical activity, sedentary time and nutritional status in Brazilian children with cerebral palsy.

OBJECTIVE: This study had the purpose investigate the physical activity (PA) and sedentary time profile of children with cerebral palsy and its association with body composition. METHODS: A cross-sectional study evaluated 53 children, between 2 and 10 years old, enrolled in three health services Recife-city, northeast of Brazil. Sedentary and PA were measured for a week using the ActiGraph GTX3 accelerometer. Body composition was assessed by anthropometry and an electrical bioimpedance device. RESULTS: Time on PA was one hour longer among the mild/moderate CP compared to severe ones, but, sedentary time is similar. Dyskinetic children spent more time in PA, but also in sedentary activities (15.5 hours a day) than spastic ones (12.8). Stunting occurred in 15 (30%) of the sample, all children with stunting had severe impairment. Underweight occurred in 25% of the severe group and 11.8% in the mild/moderate group. Overweight affected 3% of the sample; no overweight children were in the severe group. Body fat% was inversely related to time spent in moderate to vigorous PA. CONCLUSIONS: Children with CP spend more than a half of their daily time in sedentary activity. In contrast, children with mild to moderate CP spent twice as much time in moderate to vigorous PA and had a tendency (p = 0.07) to spend 50% more time in light PA. Moreover, time spent on moderate to vigorous activity was inversely related to fat mass.

Chemistry and catalytic activity of molybdenum(VI)-pyrazolylpyridine complexes in olefin epoxidation. Crystal structures of monomeric dioxo, dioxo-µ-oxo, and oxodiperoxo derivatives.

The dioxomolybdenum(VI) complexes [MoO2Cl2(PzPy)] (1) and [MoO2(OSiPh3)2(PzPy)] (5) (PzPy = 2-[3(5)-pyrazolyl]pyridine) were synthesized and characterized by vibrational spectroscopy, with assignments being supported by DFT calculations. Complex 5 was additionally characterized by single crystal X-ray diffraction. Recrystallization of 1 under different conditions originated crystal structures containing either the mononuclear [MoO2Cl2(PzPy)] complex co-crystallized with 2-[3(5)-pyrazolyl]pyridinium chloride, binuclear [Mo2O4(µ2-O)Cl2(PzPy)2] complexes, or the oxodiperoxomolybdenum(VI) complex [MoO(O2)2Cl(PzPyH)], in which a 2-[3(5)-pyrazolyl]pyridinium cation weakly interacts with the Mo(VI) center via a pyrazolyl N-atom. The crystal packing in the different structures is mediated by a variety of supramolecular interactions: hydrogen bonding involving the pyridinium and/or pyrazolyl N-H groups, weak CH · · · O and CH · · · π contacts, and strong π-π stacking. Complexes 1 and 5 are moderately active catalysts for the epoxidation of cis-cyclooctene at 55 °C using tert-butylhydroperoxide as oxidant, giving 1,2-epoxycyclooctane as the only reaction product. Insoluble materials were recovered at the end of the first catalytic runs and characterized by IR spectroscopy, elemental analysis, scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS), and powder X-ray diffraction. For complex 5 the loss of the triphenylsiloxy ligands during the catalytic run resulted in the formation of a tetranuclear complex, [Mo4O8(µ2-O)4(PzPy)4]. The recovered solids could be used as efficient heterogeneous catalysts for the epoxidation of cyclooctene, showing no loss of catalytic performance between successive catalytic runs.

Blenderized tube feeding for children: an integrative review.

OBJECTIVE: To analyze scientific evidence on the use of blenderized tube feeding in children regarding nutritional composition, family satisfaction, and health outcomes. DATA SOURCE: Survey was conducted in the PubMed, Scopus, Embase, and Virtual Health Library (VHL) databases using the following search terms: blenderized tube feeding OR blended tube feeding OR homemade OR pureed AND enteral nutrition AND enteral tube. The methodological quality of the selected articles was evaluated using the Critical Appraisal Skill Programme and Hierarchical Classification of Evidence. DATA SYNTHESIS: After analysis, 11 articles were included in the present review. Most studies demonstrated improvements in health outcomes and greater family satisfaction after replacing the commercial enteral feeding with blenderized tube feeding. CONCLUSIONS: When guided and monitored by the healthcare team, a blenderized tube feeding ensures an adequate nutritional composition. The use of this method is also associated with positive health outcomes such as reductions in gastrointestinal symptoms and hospitalizations. Moreover, a high frequency of family satisfaction was verified.

Synthesis, structure, and catalytic performance in cyclooctene epoxidation of a molybdenum oxide/bipyridine hybrid material: {[MoO3(bipy)][MoO3(H2O)]}n.

The reaction of [MoO(2)Cl(2)(bipy)] (1) (bipy = 2,2'-bipyridine) with water in a Teflon-lined stainless steel autoclave (100 degrees C, 19 h), in an open reflux system with oil bath heating (12 h) or in a microwave synthesis system (120 degrees C, 4 h), gave the molybdenum oxide/bipyridine hybrid material {[MoO(3)(bipy)][MoO(3)(H(2)O)]}(n) (2) as a microcrystalline powder in yields of 72-92%. The crystal structure of 2 determined from synchrotron X-ray powder diffraction data is composed of two distinct neutral one-dimensional polymers: an organic-inorganic polymer, [MoO(3)(bipy)](n), and a purely inorganic chain, [MoO(3)(H(2)O)](n), which are interconnected by O-H...O hydrogen bonding interactions. Compound 2 is a moderately active, stable, and selective catalyst for the epoxidation of cis-cyclooctene at 55 degrees C with tert-butylhydroperoxide (tBuOOH, 5.5 M in decane or 70% aqueous) as the oxidant. Biphasic solid-liquid or triphasic solid-organic-aqueous mixtures are formed, and 1,2-epoxycyclooctane is the only reaction product. When n-hexane is employed as a cosolvent and tBuOOH(decane) is the oxidant, the catalytic reaction is heterogeneous in nature, and the solid catalyst can be recycled and reused without a loss of activity. For comparison, the catalytic performance of the precursor 1 was also investigated. The IR spectra of solids recovered after catalysis indicate that 1 transforms into the organic-inorganic polymer [MoO(3)(bipy)] when the oxidant is tBuOOH(decane) and compound 2 when the oxidant is 70% aqueous tBuOOH.

Acid-catalysed conversion of saccharides into furanic aldehydes in the presence of three-dimensional mesoporous Al-TUD-1.

The one-pot acid-catalysed conversion of mono/di/polysaccharides (inulin, xylan, cellobiose, sucrose, glucose, fructose, xylose) into 2-furfuraldehyde (FUR) or 5-hydroxymethylfurfural (HMF) in the presence of aluminium-containing mesoporous TUD-1 (denoted as Al-TUD-1, Si/Al = 21), at 170 degrees C was investigated. Xylose gave 60% FUR yield after 6 h reaction; hexose-based mono/disaccharides gave less than 20% HMF yield; polysaccharides gave less than 20 wt % FUR or HMF yields after 6 h. For four consecutive 6 h batches of the xylose reaction in the presence of Al-TUD-1, the FUR yields achieved were similar, without significant changes in Si/Al ratio.