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Bulbophyllum orchid is used as a folk medicine in Asia. However, the concentrations of bioactive constituents in the plant may vary in different tissues. Thus, this study determined the most cytotoxic tissue extract in Bulbophyllum blepharistes Rchb.f. and identified its cytotoxic bioactive compounds. The ethanol extract from rhizomes of B. blepharistes exhibits more cytotoxicity than extracts from the leaf and pseudobulb. Ten compounds isolated from the rhizome are phenanthrenes (1, 2), bibenzyls (3, 4, 5), phenylpropanoids (6), methyl benzoate (7), along with a mixture of three alkyl acrylates (8, 9, 10). Compound 2, lusianthridin (9,10-dihydro-7-methoxy-2,5-phenanthrenediol), which was reported here for the first time in Bulbophyllum, showed cytotoxicity to H69AR, HeLa, HL-60, HepG2, and MOLT-3 cells. Compound 1 and 5 (tristin) significantly inhibited the growth of MOLT-3. The rhizome of B. blepharistes appears to be a good source for the potential anticancer agents (i.e. lusianthridin).

Methyl benzoate is a natural product (floral volatile organic compound) that is currently used as a food flavoring ingredient. This compound has shown to be insecticidal in laboratory studies against agricultural and urban pests, including spotted wing drosophila Drosophila suzukii, brown marmorated stink bug Hyalomorpha halys, the diamondback moth Plutella xylostella, and the common bed bug Cimex lectularius, to name several insect taxa. In this study we topically treated adult Aedes aegypti females with methyl benzoate and analogs and determined their toxicities. We found that among adult females, 4 analogs—butyl benzoate, n-pentyl benzoate, vinyl benzoate, and methyl 3-methoxybenzoate—were more toxic than the parent compound, methyl benzoate.

The activity of metal nitrate catalysts was investigated in the oxidative esterification reactions of benzaldehyde with hydrogen peroxide. Several types of metal nitrates (alkaline, alkaline earth, and transition metals) were evaluated as catalysts. Among the assessed salts, Fe(NO3)3 was the most efficient catalyst toward the formation of the target product (i.e., benzoic alkyl ester). In methyl alcohol, benzaldehyde was selectively oxidized to benzoic acid and then esterified to methyl benzoate. The efficiency of the catalyst was correlated with its higher Lewis acidity character, which was established through the pH measurements of methanolic solutions of the soluble metal nitrate salts. The influence of main variables of the reaction, such as catalyst load, temperature, and reactant stoichiometry, was investigated. The size of the carbon chain and steric hindrance played an essential role in the reaction selectivity. While methyl and ethyl alcohols selectively provided ester as the main product (ca. 70–75%) and acetal as the subproduct, the other alcohols gave ester, hemiacetal, and benzoic acid, which was formed in the least amount. The use of an inexpensive catalyst, a green oxidant, mild conditions, and short reaction times were the positive aspects of this one-pot process. The high TON (ca. 900) is evidence of the high catalytic activity of Fe(NO3)3. It is noteworthy that this methodology does not rely upon ligands and other additives.

Benzotriazol əsasında sintez edilmiş trans-(2-((1H-benzo [1,2,3] triazol-1-il) metil) -1,3-dioksalan-4-il) metil benzoatın sirkə (DQ-I) və xlorid turşusu (DQ-II) ilə duzları hazırlanmış, onların fiziki-kimyəvi xassələri öyrənilmiş və müxtəlif qatılıqlarda həm biosid həm də, hidrogen sulfid korroziyasına qarşı təsirləri öyrənilmişdir. Müəyyən olunmuşdur ki, hər iki reagent 15mq/l qatılıqda sulfatreduksiyaedici bakteriyalar (SRB), karbohidrogen oksidləşdirici bakteriyalar (KOB) və dəmir bakteriyalarına (FeB) qarşı 100%, hidrogen sulfid korroziyasına qarşı isə 77% mühafizə effekti göstərmişdir.

Lisianthus (Eustoma grandiflorum), a leading plant in the cut flower industry, is scentless. Here we show that lisianthus flowers have potential to produce several fragrant benzenoid-phenylpropanoids when substrate availability is not limited. To enable hyperaccumulation of substrates for the production of volatile benzenoid-phenylpropanoids, lisianthus commercial hybrid "Excalibur Pink" was transformed via floral dipping with a feedback-insensitive Escherichia coli DAHP synthase (AroG*) and Clarkia breweri benzyl alcohol acetyltransferase (BEAT), under constitutive promoters. The T1 progeny of "Excalibur Pink" plants segregated into four visual phenotypes, with pink or white colored petals and multiple or single petal layers. Interestingly, transformation with AroG* and BEAT caused no significant effect in the pigment composition among phenotypes, but did increase the levels of down-stream fragrant volatile benzenoids. All the transgenic lines exclusively accumulated methyl benzoate, a fragrant benzenoid, either in their petals or leaves. Furthermore, feeding with benzyl alcohol resulted in the accumulation of two novel benzenoids, benzyl acetate (the product of BEAT) and benzoate, as well as a dramatic increase in the concentrations of additional benzenoid-phenylpropanoid volatiles. Presumably, the degree of benzaldehyde overproduction after benzyl alcohol feeding in both leaves and flowers revealed their reverse conversion in lisianthus plants. These findings demonstrate the concealed capability of lisianthus plants to produce a wide array of fragrant benzenoid-phenylpropanoids, given high substrate concentrations, which could in turn open opportunities for future scent engineering.

The activity of the palladium salt catalysts was investigated on the benzaldehyde reactions with H2O2. The PdCl2 salt was the most efficient catalyst for the formation of the goal products. In CH3OH, benzaldehyde was selectively oxidized to benzoic acid and posteriorly esterified to methyl benzoate. In this process, the reaction of the PdCl2 catalyst with aqueous H2O2 provided H+ ions, which also promoted the esterification and acetalization reactions. The oxidant load played a key role in the selectivity controlling; while a large excess (9:1) gave benzoic acid (90%), with a lower ratio (3:1), acid and ester were formed with selectivity of 58 and 35%, respectively. With H2O2 at an equimolar ratio, the Pd(0) reduced the benzaldehyde to benzyl alcohol (30%). In absence of the oxidant, PdCl2 (2.5 mol %) condensated benzaldehyde and alcohol to acetal (90%). Therefore, PdCl2 directly catalyzed the oxidation and reduction reactions, and participated in acid-catalyzed reactions (i.e., condensation and esterification), generating H+ ions, demonstrating to be a highly versatile catalyst. An adequate adjusting of reaction conditions allowed to control the reaction selectivity toward the desired products (i.e., benzoic acid or ester benzyl, acetal, or benzyl alcohol).

Densities, speeds of sound, and viscosities of binary mixtures of methyl benzoate (MB) with ethanol, 1-propanol, and 1-butanol were measured at temperature ranging from T = 293.2 to 313.2 K and refractive indices were determined at T = 303.2 K. Excess molar volumes, VE, isentropic compressibility deviations ∆κs and viscosity deviations, Δη, were obtained and fitted with the Redlich–Kister equation with satisfactory results. Based on the measured and derived physicochemical properties, the influence of the alkyl chain length of the alcohol on the molecular interactions of the studied mixtures was explored. The results show that both hydrogen bond interaction between carbonyl group of MB and hydroxyl group of alcohol and the packing efficiency, such as accommodation of alcohol in the interstice of MB, play an important role in the microstructure of the mixtures, which leads to the disruption of alcohol with the addition of MB. Moreover, by comparing VE, ∆κs and Δη values of MB (1) + alcohol (2) systems at T = 303.2 K, it is found that the strength of hydrogen bond interaction and the packing efficiency significantly weakens with increasing alkyl chain length of alcohol in going from ethanol to 1-butanol, resulting in the VE values of the studied systems gradually changing from a negative deviation to an S shape, the ∆κs and Δη values have negative deviations, and the ∆nD values have positive deviations. The obtained results will provide thermodynamic guidance for the industrial purification of methyl benzoate.

A novel ladder-type coordination polymer (CP), poly[(μ-4,4′-bipyridine-κ2 N:N′){μ-4-[(4-carboxybenzyloxy)methyl]benzoato-κO}silver(I)](Ag—Ag), [Ag(C16H13O5)(C10H8N2)] n or [Ag(HL)(4,4′-bpy)] n {H2 L is 4,4′-[oxybis(methylene)]dibenzoic acid and 4,4′-bpy is 4,4′-bipyridine}, was synthesized using hydrothermal methods. The complex was characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction, and is a ladder-type CP which exhibits an obvious Ag—Ag interaction. The legs of the ladder are formed by parallel 4,4′-bipy ligands and silver ions, and the rungs are constructed by Ag—Ag interactions. A Hirshfeld surface analysis was carried out and is discussed in detail. The complex also displays favourable fluorescence properties.

Semi-coke-based activated carbons (SACs) were prepared using semi-coke powders as raw materials. They were modified by organic reagents (benzene, methyl benzoate, and ethyl acetate), low-temperature plasma (CH4 and N2 atmosphere), and organic reagent-low temperature plasma synergistic methods. FT-IR analysis showed that the corresponding functional groups were introduced to the surface of the SACs and the absorption peak intensities of the corresponding functional groups were enhanced via low-temperature plasma treatment. Low-temperature N2 adsorption tests showed that the organic reagent played an important role for regulated mesopores of the SACs. The adsorption capacities of the SACs for CH4 and N2 were measured via static volumetric method, and their separation factors of the CH4/N2 were calculated, in which the biggest separation factor (5.08) of CH4/N2 was obtained from the SAC-ben-P-N2, which was synergistic modified by benzene and low-temperature plasma (N2 atmosphere) and its breakthrough time of methane was 93 s. The biggest breakthrough time of methane (112 s) was acquired from the SAC-ben, which was modified by benzene and its separation factor of CH4/N2 was 4.87.

Densities and viscosities of binary mixtures of diisopropyl ether (DIPE) with methyl benzoate (MB), ethyl benzoate (EB) and benzyl acetate (BA) were measured experimentally at T = (298.15, 303.15, 308.15, and 313.15) K and P = 0.1 MPa for the entire composition range. The estimated values of the pure liquids and mixtures were subsequently used to determine the properties such as excess molar volume (VE), deviation in viscosity (∆η), and excess Gibbs free energy (∆G*E). These results were fitted into Redlich–Kister polynomial equation to calculate the coefficients and standard errors.

We evaluated a botanical compound, methyl benzoate, which was previously shown to have insecticidal activity on several agricultural pests, for its behavioral action on the common bed bug, Cimex lectularius L. Methyl benzoate, along with acetophenone and Cirkil™, a commercially available bed bug control product, exhibited repellent action against bed bugs in an EthoVision video system designed to track the movement of individuals.

A new chromatographic stationary phase was prepared by making a soft organic monolith based on thermal polymerization of methyl methacrylate and ethylene glycol di-methacrylate with an aid of gas evolution via decomposition of urea, and by crushing the monolith into particles. The original purpose of urea incorporation was formation of monolith particles with affluent mesopores, but the actual effect was reduction of the particle size to a proper range (mostly in the range of 1–5 μm with an average of ca. 3 μm), which was very crucial for improvement of separation efficiency. A series of washing processes (including common washing and reflux washing) were carried out to remove un-reacted materials and free oligomers. The columns were made by packing the organic monolith particles in glass-lined stainless-steel tubing and evaluated for their performance with the mixture of six aromatic compounds (3-phenyl-1-propanol, acetophenone, methyl benzoate, 2-nitroaniline, ethylbenzene, cumene). The overall number of theoretical plates (N) over 6 analytes based on 6 columns was 32,000 plates/column (107,000 plates/m, 9.4 µm plate height).

Methyl benzoate (MB) is synthesized in a batch reactor conventionally and with the use of microwave (MW) energy as a source of heat. MW-assisted esterification has added advantage of competent energy use in volumetric region which provides a safe, economic and green method of heating. In microwave-assisted MB esterification, the amount of solvent is minimized. Also this work aims to study the product distribution and selectivity using heterogeneous zeolite Hβ catalyst. The esterification is studied by variation in operating conditions such as reaction time, feed composition, microwave energy and reaction temperature. It has been found that 88% conversion of BA with 74% selectivity of MB is formed using a conventional batch reactor, while with the use of MW energy as a source of heating, at 70 °C, 300 W MW power, 99.99% conversion of BA was achieved within 10 min with the highest selectivity of 86% using sulfuric acid and 67% of MB using Hβ catalyst, respectively.

In recent years, industrial contaminants and especially organic pollutions have been threatening both environmental safety and human health. Particularly, dibutyl phthalate (DBP) has been considered as one of the major hazardous contaminants due to its widespread production and ecological toxicities. Consequently, reliable methods toward the efficient and environmentally benign degradation of DBP in wastewater would be very desirable. To this end, a novel magnetically separable porous TiO2/Ag composite photocatalyst with magnetic Fe3O4 particles as the core was developed and successfully introduced to the photocatalytic degradation of DBP under visible irradiation with a fluorescent lamp. The presented work describes the grafting of Ag co-doped TiO2 composite on the silica-modified porous Fe3O4 magnetic particles with a simple and inexpensive chemical co-precipitation method. Through the investigation of the influencing factors including photocatalyst dosage, initial concentration of DBP, solution pH, and H2O2 content, we found that the degradation efficiency could reach 74%. The photodegradation recovery experiment showed that the degradation efficiency of this photocatalyst remained almost the same after five times of reuse. In addition, a plausible degradation process was also proposed involving the attack of active hydroxyl radicals generated from this photocatalysis system and production of the corresponding intermediates of butyl phthalate, diethyl phthalate, dipropyl phthalate, methyl benzoate, and benzoic acid.

Acoustical-Debye temperature and Surface tension studies are estimated for liquid mixtures of MB (Methyl Benzoate) + 1-Octanol over entire molefraction range of MB at different temperatures T = (303.15, 308.15, 313.15 and 318.15) K. An analogy of Debye temperature along with the Viscosity and Surface Tension variations are scrutinized to bring out the molecular contribution to thermal energy changes of binary liquid mixtures. The observed and obtained results are used to explain thermal behaviour and molecular association between the component molecules of liquid mixtures.

Esters are potential acyl donors but are relatively unexplored for that purpose. A facile installation of acyl groups at the C-3 position of indoles under triflic acid catalysed conditions with easily available and cheap esters as new acylating agents is described herein. Furthermore, heterocycles like N-protected pyrrole, furan and thiophene were also suitable substrates for similar C-2 acylation. Analogous C-3 benzoylated products of indole were obtained, albeit in lower yields, by using methyl benzoate as a benzoyl donor. The benzoylated products were synthesised in much better yields via a copper(ii) catalysed aerial oxidation of indole containing benzoins.

Viscosities have been evaluated for functional binary liquid mixtures of MB (Methyl Benzoate) + 1-Octanol using Bingham relation, Kendall-Munroe relation, Arrhenius- Eyring relation, Croenaurer-Rothfus-Kermore relation and Gambrill relation. The validity of these theories has been verified by respective deviations between calculated values and experimental values. The results of all the theories are comparatively in good agreement with experimental results.

Selective cleavage of C-C bonds is very important in organic chemistry, but remains challenging because of their inert chemical nature. Herein, we report that Zn/NC-X catalysts, in which Zn2+ coordinate with N species on microporous N-doped carbon (NC) and X denotes the pyrolysis temperature, can effectively catalyze aerobic oxidative cleavage of C(CO)-C bonds and quantitatively convert acetophenone to methyl benzoate with a yield of 99% at 100 °C. The Zn/NC-950 can be applied for a wide scope of acetophenone derivatives as well as more challenging alkyl ketones. Detail mechanistic investigations reveal that the catalytic performance of Zn/NC-950 can be attributed to the coordination between Zn2+ and N species to change the electronic state of the metal, synergetic effect of the Zn single sites with their surrounding N atoms, as well as the microporous structure with the high surface area and structural defects of the NC., Selective cleavage of C-C bonds is very important in organic chemistry, but remains challenging because of their inert chemical nature. Here, the authors report that Zn2+ coordinated with N species on N-doped carbon catalysts can catalyze the aerobic oxidative cleavage and esterification of C(CO)-C bonds with high efficiency and activity.

Boron nitride (BN) has attracted great attention with an unexpected ability in aerobic catalysis. Still, its related probe reactions are relatively rare, and the effect of the BN-supported metal catalyst on O2 activation is still ambiguous, and opinions are varied. In this work, the porous BN (pBN)-supported Au catalyst with a porous structure and exposed edges exhibits high activity in the oxidative cross-esterification reactions between the aromatic and C1-C3 aliphatic alcohols at ambient temperature. The turnover frequency value for methyl benzoate is 118 h-1 at 30 °C, and the calculated apparent activation energy (Ea, 58 kJ/mol) is comparable to that of AuPd/TiO2, Ru/Al2O3, and PdBiTe catalysts. Combined with temperature-programmed desorption (TPD) results, the loading of Au enhances the desorption of O2 and the interaction with alcohols; thus, a synergistic effect between the O-rich pBN and Au is considered. The free-radical scavenger can dramatically suppress the conversion (∼6%), suggesting that the reaction proceeds via the O2* radicals. According to the vibration of νO-O, δOO-H, and νB-O-O-B detected by attenuated total reflectance-infrared spectroscopy (ATR-IR), we are prone to consider the oxygen activation route by the edge B atoms. Then, a possible L-H reaction mechanism was proposed: benzyl alcohol and O2 adsorb on the Au/pBN initially, then O2 is converted to O2*, and the α-H elimination proceeds; as the semi-acetal formed, another α-H elimination proceeds and methyl benzoate is finally formed.

Methyl benzoate-based vortex-assisted surfactant-enhanced emulsification microextraction (VASEME) has been developed and applied for the preconcentration of fungicides (i.e., carbendazim, thiabendazole and fluberidazole) and their subsequent determination by high performance liquid chromatography. Methyl benzoate (as extraction solvent) and sodium dodecyl sulfate (as emulsifier) were used in VASEME. Parameters affecting the extraction performance were investigated and optimized. Under the optimum conditions, linearity was obtained in the range of 0.1–200 μg/L with the coefficient of determination exceeding 0.998. Limits of detection and quantitation were 0.01–0.5 and 0.1–3 μg/L, respectively. Recoveries of the spiked analytes (10–100 μg/L) from fruit juice samples were between 72 and 116% with the relative standard deviation below 10%. The proposed method is simple, rapid, consuming less solvent, sensitive and reliable for the determination of fungicide residues in fruit juice samples.

Common bed bug Cimex lectularius (L.) (Hemiptera: Cimicidae) infestations are on the rise and due to the development of pesticide resistance they are becoming more difficult to control, affordably. We evaluated a naturally occurring compound methyl benzoate (MB) and related analogs, previously reported to have insecticidal activity on several agricultural pests, for its fumigant action on the common bed bug, C. lectularius L. A discriminating concentration was used to determine the effectiveness of MB, and several of its analogs as fumigants in a laboratory assay. It was found that MB provided >90% control of adult bed bugs in this laboratory fumigant assay. LC50 values were calculated for MB against both a pyrethroid-susceptible and a pyrethroid-resistant strain of common bed bugs. It was determined that both strains were susceptible in this laboratory assay. However, when MB was tested in a field-like assay and compared to a commercially available bed bug control product, it was found to be significantly less effective compared to the commercial product. Our study has found that while MB has the potential to be used as a bed bug control agent, refinements in the delivery system will be needed to increase efficacy under field-like conditions.

A volatile alkaloid quinoline-4-carbonitrile (QCN) was isolated from the floral extract of Quisqualis indica. Major compounds were trans-linalool oxide (1.0, 4.5%), methyl benzoate (1.0, 4.0%), 2,2,6-trimethyl-6-vinyl-tetrahydropyran-3-one (7.4, 17.8%), 2,2,6-trimethyl-6-vinyl-tetrahydropyran-3-ol (1.0, 1.2%), (E,E)-α-farnesene (29.1, 16.1%), QCN (5.7, 1.3%) in live and picked flowers, respectively. Flower compositions were altered due to change in enzymatic reaction at the time of picking. Some rearrangements of oxygenated terpenoids occurred in the process of hydrodistillation to obtain essential oil. Chemical synthesis of QCN and its selectively reduced products derived from QCN were prepared through green reaction process. The catalytic modification of QCN has produced quinoline-4-methylamine; the later compound has shown enhanced bio-activities. QCN and floral extract (absolute) have shown potential anti-inflammatory and antioxidant activities. Besides, floral absolute has shown significant anti-inflammatory and antioxidant activities due to improved QCN (19.7%) content to synergize amongst terpenoids and benzenoids as compared to the essential oil with 1.1% of QCN.

A bi-functional cobalt and nitrogen co-doped carbon catalyst was fabricated by calcinating the chelate compound containing citric acid, melamine and CoCl2·6H2O in N2, with the mixed salts of LiCl and KCl as the template. Co and N species are highly dispersed in the target catalyst, which has a high surface area of 1011 m2 g−1. Such structure enables it to efficiently catalyze the direct aerobic oxidative esterification of benzyl alcohol with methanol to the ester of methyl benzoate; meanwhile, it exhibits superior potential ability for the application of oxygen reduction reaction, which is a vital process happening on the cathode of fuel cells and metal-air batteries.

Historically, stored product insect pest management has been based around the use of methyl bromide and phosphine as fumigants. However, methyl bromide has been phased out for structural fumigations, and there is increasing worldwide insecticide resistance to phosphine. One potential alternative, environmentally friendly option is the use of methyl benzoate (MBe), which is considered a food safe compound. In this study, we evaluated the direct and sublethal effects of MBe exposure on the survivorship and mobility of four stored product species with diverse life histories, including Rhyzopertha dominica, Tribolium castaneum, Sitophilus zeamais, and Trogoderma variabile. Sets of insects were exposed to a control, low, or high MBe concentrations in flasks with or without food for 24 or 72 h in the laboratory. Furthermore, we assessed phosphine exposure under similar conditions. Overall, R. dominica was the most susceptible to MBe exposure, followed by T. castaneum. By contrast, S. zeamais and T. variabile were relatively unaffected by MBe exposure. Exposure to MBe induced multiple-fold decreases in the total distance moved and velocity of adults still considered alive or affected after assays. By comparison, phosphine effectively killed all individuals of all species. Our data suggest that while MBe was effective for R. dominica, it was not competitive in comparison to phosphine for controlling susceptible strains of these species at the specified experimental conditions.

Platanthera bifolia subsp. osca sample collected at Grisolia showed as main components linalool (17.8%), benzyl benzoate (55.8%), and benzyl 2-hydroxybenzoate (6.7%). Four samples of P. bifolia subsp. osca were collected at Pignola: the main components of the aroma are lilac derivatives (49.02-79.00%), mainly lilac alcohols B (7.41-13.52%), C (10.10-18.45%), and D (7.50-34.28%). Three samples were analyzed from the site of Marsico Nuovo. The main components of the scent found in this site were linalool (1.54-10.00%), lilac aldehydes (3.98-11.15%), and mainly lilac alcohols (50.68-61.51%). The main components of the sample collected at Palena were methyl benzoate (9.04%) and benzyl benzoate (74.72%). The analysis of the composition of the aroma of a Platanthera chlorantha plant has been performed. The main components were lilac derivatives. The reported behavior could be explained admitting an adaptive modification of the scent considering the nature of possible pollinating agents due to different habitats.

The oxidation capacity and mechanisms involved in activation of peroxomonosulfate (PMS) by nanoscale zero valent tungsten (nZVW) were investigated with dimethyl phthalate (DMP) as a targeted contaminant. DMP removal was completely achieved by hydroxyl radical ( OH) and sulfate radical ( SO4−) at 50 min in the nZVW/PMS system, and structural and componential changes of nZVW powder before and after reaction were not obvious. Low valence tungsten species were released during nZVW corrosion in oxygenated water via heterogeneous reactions, which was accelerated by PMS. The homogeneous reactions were mainly responsible for radical generation: 1) the stepwise oxidation of nZVW to produce H2O2, which was then activated by low valence tungsten species to generate OH; 2) the activation of PMS by low valence tungsten species to produce SO4− and OH. However, OH− reduced the reactivity of low valence tungsten species due to the formation of tungstate, higher pH thus partly inhibited the DMP removal. Two stages of DMP removal were found, and DMP degraded dramatically in the second stage. The degradation pathways of DMP were proposed, involving the formation of aromatic esters (monomethyl phthalate, methyl benzoate, and methyl salicylate), aromatic acids (phthalic acid, salicylic acid, and benzoic acid), and phenols (catechol, phenol, and hydroquinone) in turn. These results help to comprehend the application of nZVW in reactive radicals-based oxidation processes and the reactivity of low valence tungsten species in water treatment field.

The Cu/ZnO/Al2O3 catalysts prepared by co-precipitation method were used for the hydrogenation of methyl benzoate to benzyl alcohol. These catalysts were characterized at various stages of preparation by nitrogen adsorption–desorption, X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR), and X-ray photoelectron spectroscopy (XPS). The experimental results show that the addition of ZnO to the catalyst greatly improves the selectivity of benzyl alcohol. When the Cu/Zn/Al molar ratio is 2:2:1 and the calcination temperature of the catalyst is 650 °C, the catalyst exhibits very highly catalytic performance. In addition, the effects of reaction temperature, pressure and time were also investigated during the hydrogenation of methyl benzoate to benzyl alcohol. When the methyl benzoate was hydrogenated over this catalyst at 160 °C and 7 MPa of H2 for 10 h, the conversion of methyl benzoate can reach 93.89% and the selectivity of benzyl alcohol is 88%. This effectively catalytic performance can be attributed to the presence of highly dispersed and stable metallic copper nanoparticles, and the weak acidity of the catalyst surface. Besides, the reaction pressure and temperature play a crucial role in the conversion of methyl benzoate and the selectivity of benzyl alcohol. Application of Cu/ZnO/Al2O3 catalyst in hydrogenation of methyl benzoate to benzyl alcohol.

Trypophloeus klimeschi Eggers (Coleoptera: Curculionidae: Scolytinae) was first discovered in China in 2003, and it exhibits strong species specificity to Populus alba var. pyramidalis Bunge (Salicaceae). To screen plant volatile compounds for monitoring and trapping T. klimeschi, the electroantennogram responses of adult T. klimeschi to eight plant volatiles, including nonanal, 2-methylbutanal, decanal, 2-hydroxybenzaldehyde, (Z)-3-hexen-1-ol benzoate, methyl benzoate, methyl salicylate, and geraniol were tested at various concentrations. Behavioural responses of female and male adults to various concentrations of these eight plant volatiles were also determined using a Y-tube olfactometer. We then tested the effectiveness of these compounds as lures for trapping T. klimeschi in the field. Electroantennogram tests showed that T. klimeschi possesses olfactory sensitivity for eight compounds. Additionally, walking T. klimeschi exhibited attraction to low concentrations (≤ 1 μg/μL) of all eight compounds in Y-tube olfactometer. Field experiment results indicated that baits composed of each volatile compound alone were more attractive to greater numbers of T. klimeschi than the control. The methyl benzoate bait was better attracted by T. klimeschi than other tested volatiles. These results suggest that these compounds could be used in attraction of this stem-boring pest. This study could have important implications for the development of an effective semiochemical-based management tool for T. klimeschi in the field.

This paper focuses on specific features of the low-temperature (60°C) oxidative esterification reaction of benzyl alcohol with methanol on cobalt-nitrogen-carbon heterogeneous catalyst produced by carbonization of a ZIF-67 metal-organic framework structure. The optimal temperature range of pyrolysis for preparing high-activity catalyst samples was determined. The influence exerted by bases, such as K2CO3, Na2CO3, triethylamine, para-dimethylaminopyridine, and other additives on the rate and selectivity of the catalytic reaction was examined. It was shown that the esterification occurs via the intermediate formation of benzaldehyde, which is rapidly transformed to methyl benzoate in the presence of a base.

A series of ionic (mono‐/di‐)phosphines (L2, L4, and L6) with structural similarity and their corresponding neutral counterparts (L1, L3, and L5) were applied to modulate the catalytic performance of RuCl3 ⋅ 3H2O. With the involvement of the ionic diphosphine (L4), in which the two phosphino‐fragments were linked by butylene group, RuCl3 ⋅ 3H2O with advantages of low cost, robustness, and good availability was found to be an efficient and recyclable catalyst for the alkoxycarbonylation of aryl halides. The L4‐based RuCl3 ⋅ 3H2O system corresponded to the best conversion of PhI (96 %) along with 99 % selectivity to the target product of methyl benzoate as well as the good generality to alkoxycarbonylation of different aryl halides (ArX, X=I and Br) with alcohols MeOH, EtOH, i‐PrOH and n‐BuOH. The electronic and steric effects of the applied phosphines, which were analyzed by the 31P NMR for 1 J 31 P‐ 77 Se 1 J measurement and single‐crystal X‐ray diffraction, were carefully co‐related to the performance RuCl3 ⋅ 3H2O catalyst. In addition, the L4‐based RuCl3 ⋅ 3H2O system could be recycled successfully for at least eight runs in the ionic liquid [Bmim]PF6.

Carbon capture, utilization and sequestration technology is effective for carbon emissions reduction. The development of new absorbent seems to be one of the core components of carbon capture technology. In this paper, three esters, methyl heptanoate, ethyl hexanoate and methyl benzoate, were selected to determine CO2 solubilities at different temperatures ranging from 293.15 to 333.15 K, and pressures up to 1.2 MPa, using the isothermal synthesis method. The results showed that the absorbent with the straight-chain alkyl group was more effective for improving CO2 absorption capacity than the benzene group. Ethyl hexanoate showed slightly higher CO2 solubilities than its isomer methyl heptanoate. In addition, Henry’s constant and thermodynamic properties such as solution enthalpy, solution entropy, solution Gibbs energy and solution heat capacity, were determined based on the measured data since the above properties are essential for designing an absorption process. Ethyl hexanoate is superior to the other two selected absorbents, common solvents, commercial absorbents, some physical absorbents, some polymeric absorbents and some ionic liquids, which indicates that it has potential value for CO2 capture technology. However, further studies will be necessary to assess the reliability of its industrial application.

Six ester absorbents were selected for CO2 capture, such as methyl benzoate, methyl heptanoate, ethyl hexanoate, butyl butyrate, triethyl phosphate and tributyl phosphate. CO2 solubilities in these absorbents were determined under temperatures of 273.15–283.15 K, and pressures up to 1.2 MPa. Henry’s constants of CO2 + the selected absorbent systems at 273.15 K and 283.15 K were calculated and compared with those at higher temperature. It seemed that decreasing the absorption temperature is obviously beneficial for enhancing absorption performance. In order to assess the absorption capacity for different physical absorbents, Henry’s constants and volumetric solubilities of the selected absorbents were compared with ionic liquids, common solvents and the selected absorbents in our previous work. The result showed that tributyl phosphate and triethyl phosphate were found to be relatively good absorbents by mole and volumetric fraction respectively, and they have potential value for CO2 capture. Moreover, thermodynamic properties such as entropy of solution, enthalpy of solution and Gibbs free energy of solution for the selected systems were calculated and assessed to study the absorption behavior.

We recently developed a simultaneous measurement system combining a wide Q-range SANS instrument and a Fourier-transform infrared (FTIR) spectrometer equipped with an infrared polarizer. The information of high Q neutron scattering and FTIR spectra helps to increase the reliability of structural analysis by SANS on complicated systems. In this study, we applied this simultaneous measurement system to a cocrystal system of syndiotactic polystyrene (sPS) and methyl benzoate (MeBA). The neutron scattering provided the evidence that MeBA molecules were certainly incorporated into the crystalline region of sPS. The polarized FTIR measurements showed that the guest MeBA has a certain orientation against the sPS lattice. With the help of different kinds of structure information, the thermal behavior of sPS/MeBA cocrystal was able to be analyzed in detail.

Rutin (3',4',5,7-tetrahydroxy-flavone-3-rutinoside) was enzymatically acylated with benzoic acid and its esters (methyl benzoate and vinyl benzoate) using Thermomyces lanuginosus lipase (Lipozyme TLIM). The acylation reaction was optimized by varying the reaction medium, reaction temperature, acyl donor, substrate molar ratio, and reaction time. The highest conversion yield (76%) was obtained in tert-amyl alcohol (60 °C, 72 hr) using vinyl benzoate (molar ratio of 1:10) as acyl donor. The acylation occurred at the 2'''-OH and 4'''-OH of the rhamnose unit and the 2''-OH position of the glucose moieties. Three novel rutin acylated derivatives (compounds 1-3) were purified and characterized by HR-MS and 1D and 2D NMR spectroscopy. We found that acylation significantly improved lipophilicity, capacity to inhibit lipid peroxidation, anticancer capacity and substantially maintained the antioxidant activity of rutin. This research provides important insights in the acylation of flavonoids with different glycosyl moieties. PRACTICAL APPLICATION: In this study, three novel rutin derivatives were successfully synthesized and the highest conversion yield (76%) was obtained by reacting the rutin and vinyl benzoate at molar ratio of 1:10 in tert-amyl alcohol for 72 hr at 60 °C. Introducing a benzoic acid substituent into rutin molecule significantly improved their lipophilicity and inhibition of lipid peroxidation in lipophilic system. Furthermore, this study demonstrated that acylation significantly improved anticancer capacity and substantially maintained the antioxidant activity.

Methyl benzoate is a constituent of floral scent profile of many flowering plants. However, its biosynthesis, particularly in monocots, is scarcely reported. The monocot Hedychium coronarium is a popular ornamental plant in tropical and subtropical regions partly for its intense and inviting fragrance, which is mainly determined by methyl benzoate and monoterpenes. Interestingly, several related Hedychium species lack floral scent. Here, we studied the molecular mechanism of methyl benzoate biosynthesis in H. coronarium. The emission of methyl benzoate in H. coronarium was found to be flower-specific and developmentally regulated. As such, seven candidate genes associated with methyl benzoate biosynthesis were identified from flower transcriptome of H. coronarium and isolated. Among them, HcBSMT1 and HcBSMT2 were demonstrated to catalyze the methylation of benzoic acid and salicylic acid to form methyl benzoate and methyl salicylate, respectively. Methyl salicylate is a minor constituent of H. coronarium floral scent. Kinetic analysis revealed that HcBSMT2 exhibits a 16.6-fold lower Km value for benzoic acid than HcBSMT1, indicating its dominant role for floral methyl benzoate formation. The seven genes associated with methyl benzoate biosynthesis exhibited flower-specific or flower-preferential expression that was developmentally regulated. The gene expression and correlation analysis suggests that HcCNL and HcBSMT2 play critical roles in the regulation of methyl benzoate biosynthesis. Comparison of emission and gene expression among four Hedychium species suggested that coordinated and high-level expression of biosynthetic pathway genes is responsible for the massive emission of floral methyl benzoate in H. coronarium. Our results provide new insights into the molecular mechanism for methyl benzoate biosynthesis in monocots and identify useful molecular targets for genetic modification of scent-related traits in Hedychium.

A range of n-type and p-type metal oxide semiconductor gas sensors based on SnO2 and Cr2O3 materials have been modified with zeolites H-ZSM-5, Na-A and H–Y to create a gas sensor array able to successfully detect a cocaine by-product, methyl benzoate, which is commonly targeted by detection dogs. Exposure to vapours was carried out with eleven sensors. Upon data analysis, four of these that offered promising qualities for detection were subsequently selected to understand whether machine learning methods would enable successful and accurate classification of gases. The capability of discrimination of the four sensor array was assessed against nine different vapours of interest; methyl benzoate, ethane, ethanol, nitrogen dioxide, ammonia, acetone, propane, butane, and toluene. When using the polykernel function (C = 200) in the Weka software – and just five seconds into the gas injection – the model was 94.1% accurate in successfully classifying the data. Although further work is necessary to bring the sensors to a standard of detection that is competitive with that of dogs, these results are very encouraging because they show the potential of metal oxide semiconductor sensors to rapidly detect a cocaine by-product in an inexpensive way.

Semi-volatile organic compounds (SVOCs) are organic compounds with the boiling point ranging between 240/260 ℃ and 380/400 ℃. Detailed knowledge regarding catalytic removal of SVOCs from indoor environment is very limited as it remains challenge to explore such reaction due to the viscosity nature of target contaminants. Here, we established a facile methodology to explore the heterogeneous catalytic oxidation reaction of dimethyl phthalate (DMP), a model SVOC, over the surface of supported catalyst. DMP was found to be gradually oxidized over the surface of titania supported catalysts including palladium (Pd), platinum and ruthenium with increasing temperature. The cleavage of side chain of DMP occurs at 75 ℃ over the surface of Pd/TiO2, which is significantly lower than that of the other two catalysts. Carbon dioxide was observed as the main product of the catalytic oxidation reaction. However, aromatic products and small molecule products were still observed as side-product in different temperature range. Density functional theory calculations further show that DMP can react with reactive oxygen species to form phthalic acid. While the cleavage of the DMP side chain occurs to form products such as methyl benzoate. This work thus provides basic knowledge about indoor SVOCs catalytic oxidation removal.

Layered double hydroxide-supported Au–Cu alloy nanoparticles (NPs) were found to be highly efficient catalysts for the oxidative esterification of benzyl alcohol with methanol in the presence of molecular oxygen under visible-light irradiation to prepare methyl benzoate. Here, we report that alloying small amounts of copper into gold nanoparticles can increase the ability to activate oxygen molecules to O2˙− radicals and display greater charge heterogeneity to promote the cleavage of the C–H bond of benzyl alcohol molecules by reinforcing the coordination of the intermediate with unsaturated metal active sites due to the LSPR effect of alloy NPs, which is the rate-limiting step of the reaction. Besides the Au–Cu alloy NPs, the support also played a pivotal role in the catalytic process. The support with the presence of acid–base pairs, in which the basic sites served as the reactant molecule adsorption sites to provoke the intermediate formation and the acidic sites promoted the recovery of the support surface, showed better performances by affecting the overall reaction rate completely. Moreover, applying this photocatalyst in the cross-esterification of aromatic alcohols and aliphatic alcohols displayed excellent yields.

Benzenoid aromatic compounds are the most important scent components of Dianthus, although some wild Dianthus species also produce terpenoids and fatty acid derivatives as principal scent components, and thereby having diverse scents. The scent of Dianthus carnations is described as spicy and is generally ascribed to eugenol. Our research shows lower diversity of carnation scents than wild Dianthus scents and differing main scent types among cultivars for cut and potted flowers. We also found that scents of most of the current cultivars for cut flowers were not spicy and had fruity notes derived from methyl benzoate. In addition, scent emissions decreased sharply after harvesting, and were almost absent after a few days. In this chapter, we describe the chemistry of scents from the current carnation cultivars. In plants, methyl benzoate is usually synthesized from benzoic acid by benzoic acid carboxyl methyltransferases (BAMT). Hence, the corresponding gene BAMT is considered important for scent biosynthesis in carnations. From nucleotide sequence analyses of the carnation genome, more than 10 candidate BAMT genes were found. We describe the characteristics of this gene and its homologs in the second half of this chapter.

This study aimed to characterize the aromatic profile of the flesh and peel (periderm/epidermis) of feijoa fruit, of cultivars Alcântara and Nonante, in response to Protected Environment Cultivation with plastic cover (PEC) and cold storage. A completely randomized design was used for each cultivar, with a two-factor scheme consisting of two cultivation systems (Protected Environment Cultivation with plastic cover (PEC) and Direct Sunlight without plastic cover (DS)) and two different maturity stages (at harvest, and after storage (14 days at 4 ± 0.1 °C/94±2% of relative humidity RH, followed by two days at 20±2 °C/60±5% RH). The aromatic volatiles found in a higher relative percentage, in both cultivars, were: in the flesh, esters (methyl benzoate, ethyl benzoate, ethyl butanoate, ethyl acetate, (Z)-3-hexenyl acetate, ethyl hexanoate) and aldehyde ((E)-2-hexenal); and in the peel, the same ester compounds found in flesh (except for ethyl hexanoate), as well as terpenes (humulene, β-caryophyllene, ledene, α-terpineol, α-cubenene, and α-bourbonene). Besides these, alcohols (linalool, 3-octanol) and ketones (3-octanone) also comprised aromatic profile of the peel. Ester compounds contribute differently to the aromatic profile of the cultivars. In general, aldehydes (mainly ((E)-2-hexenal) and terpenes have a greater relative contribution in the cultivars Alcântara and Nonante, respectively. In general, plants under PEC had increased content of terpenes and reduced esters, which causes a more pronounced herbaceous aroma in these fruit. The cold storage of Alcântara and Nonante cultivars favors the development of the characteristic aroma of these fruit when ripe, particularly due to reduced content of some compounds presenting herbaceous characteristics and increased content of fruity/sweet compounds in the aromatic profile.

The drying technology plays an important role in aroma quality. Herein, the dynamic change of volatile profiles of green tea under different temperature gradients and duration were analyzed by using gas phase electronic nose (GC-E-Nose) and gas chromatography-ion mobility spectrometry (GC-IMS) combined with multivariate statistical analysis. A total of 33 compounds were identified. Three drying stages could be clearly discriminated from the samples with different drying time, and 20-min-drying was a key transition point. 3-Methylbutanal, isopropyl alcohol, methyl benzoate, and heptanal were found to play an important role in discrimination of the above three stages, basing on variable importance in projection ＞1.2 and p＜0.01. The volatile profiles changed dynamically with increasing drying temperature, and the significant change occurred under the temperature of 105 °C. In addition, the GC-E-Nose could quickly and effectively characterize the dynamic changes under different drying conditions, and verified and complemented the GC-IMS analysis results. This study provides comprehensive insight into variation in the volatile metabolite profile during the drying process of green tea.

A convenient, expeditious, and high-efficiency protocol for the transformation of alcohols into esters using a Co-modified N-doped mesoporous carbon material (Co-N/m-C) as the catalyst is proposed. The catalyst was prepared through direct pyrolysis of a macromolecular precursor. The catalyst prepared using a pyrolysis temperature of 900 °C (labeled Co-N/m-C-900) exhibited the best performance. The strong coordination between the ultra-dispersed cobalt species and the pyridine nitrogen as well as the large area of the mesoporous surface resulted in a high turnover frequency value (107.6 mol methyl benzoate mol−1 Co h−1) for the direct aerobic oxidation of benzyl alcohol to methyl benzoate. This value is much higher than those of state-of-the-art transition-metal-based nanocatalysts reported in the literature. Moreover, the catalyst exhibited general applicability to various structurally diverse alcohols, including benzylic, allylic, and heterocyclic alcohols, achieving the target esters in high yields. In addition, a preliminary evaluation revealed that Co-N/m-C-900 can be used six times without significant activity loss. In general, the process was rapid, simple, and cost-effective.

Persistent room-temperature phosphorescence (p-RTP) of pure organic materials is attracting increasing attention. The design of efficient phosphors and understanding the origin of p-RTP, however, remain challenging. Herein, to gain further insights into pure organic p-RTP, we prepared a group of carbazole (CZ) and methyl benzoate (MBA) conjugates with a methyl ester unit at the para (4-MBACZ), meta (3-MBACZ), and ortho (2-MBACZ) sites. These isomers merely produce prompt fluorescence in solutions, but generate blue prompt/delayed fluorescence (DF) and orange p-RTP with lifetimes up to 865.2 ms in the crystalline state. Lifetimes of p-RTP are in the order of 2-MBACZ>3-MBACZ>4-MBACZ, which might be mainly ascribed to the combined effect of packing density, intermolecular interactions and steric hindrance. Meanwhile, upon mechanical grinding, while the emission color and profile of the luminogens do not significantly change, no (4-MBACZ) or shortened (3-MBACZ, 2-MBACZ) p-RTP is observed, accompanying the change from crystalline to amorphous states. Such p-RTP at amorphous states without external hosts is rarely reported, which demonstrates important implications for the molecular design and mechanism understanding towards p-RTP. Furthermore, their p-RTP attribute and different emission colors before and after ceasing the UV irradiation endow them promising applications in encryption and anticounterfeiting fields.

Methyl-esterification of oxygenates such as alcohols, aldehydes and carboxylic acids were carried out by employing copper and copper/palladium based catalysts using TBHP. In this reaction, TBHP plays dual role as oxidizing and methylating agent. Cu and Cu-Pd based nanoperticles (NPs) were prepared by wet chemical method using CuCl or PdCl2 by engaging “green solvent” water and dextrose as eco-friendly and renewable reagents. The NPs were fully characterized using various physicochemical techniques such as XRD, SEM, TEM and EDAX. XRD spectra of synthesized NPs confirmed the formation of CuO and Pd/Cu2Cl(OH)3. HRTEM analysis of CuO confirmed uniform cube-shaped morphology with particle size of 25–30 nm. Whereas, HRTEM of Pd/Cu2Cl(OH)3 showed 5–10 nm Pd NPs uniformly dispersed over Cu2Cl(OH)3 surface. Excellent catalytic activity was obtained for the conversion of benzaldehyde to methyl benzoate with 92% selectivity using Pd/Cu2Cl(OH)3 nanocatalyst. Other oxygenates such as aldehydes, alcohols and carboxylic acids were also obtained with high conversion and selectivity for desired methyl esters.

Hydrogenation of butyl sorbate into butyl Z-hex-3-enoate in supercritical carbon dioxide proceeds at high conversion and selectivity of 93–96% under catalysis with chromium hexacarbonyl at 180 °C and on using (methyl benzoate)chromium tricarbonyl as a catalyst at 160 °C.

The impact of double bond modification by gem-difluorocyclopropanation (gDFC) in poly(norbornenes) backbone on their gas transport properties was studied for the first time. With this aim the research of gDFC of polynorbornene (PNB) and poly(5-trimethylsilylnorbornene) (PNBSi) in the conditions of sodium chlorodifluoroacetate thermolyses at 180–190 °C in methyl benzoate solution were carried out. The starting poly(norbornenes) were synthesized via ring-opening metathesis polymerization of the corresponding monomers mediated by the first generation Grubbs’ catalyst. The degree of double bonds conversion into the gem-difluorocyclopropane and the molecular weight of modified polymers could be controlled by adjusting the reaction time, sodium chlorodifluoroacetate amount, and polymer concentration in reaction mixture, as well as by addition of inhibitor. The bulky Me3Si-substituent hindered the modification of double bonds in poly(norbornenes)’ backbone. The gDFC decreased the thermal stability of poly(norbornenes). However, the films of modified polymers demonstrated high stability during storage at the ambient conditions, especially in comparison with unmodified polynorbornene. The introduction of gem-difluorocyclopropane in poly(norbornenes) backbone increased their gas permeability coefficients P especially strongly for PNB. Simultaneously the values of ideal selectivity αij = Pi/Pj were not changed or slightly increased. The noted growth of P was caused by increases in the solubility coefficients S. To elucidate the role of the two types of modification fragment ( CF2 and O ) of double bonds a sample was prepared that included both types of the fragments. It was distinguished by increased P and αij values. So, a new and simple approach improving the gas permeation properties of metathesis polynorbornenes was developed. It may be extendable to broader families of polydienes and other polymers containing double bonds in the backbone.

Covalent triazine frameworks (CTFs) were reported to be effective in the oxidative cleavage of the lignin model compound 2-phenoxyacetophenone, as metal-free catalysts with O2, producing phenol, benzoic acid, methyl benzoate and methyl benzoylformate as the major products. Combining the detailed characterizations with the reaction results, the triazine structure with unique properties of CTFs contributes to their superior catalytic performance. Mechanism investigation, including isotope-labeling, radical trapping and intermediate verification experiments, was carried out. CTFs promoted the decomposition of peroxide and cleavage of both the C–C bond and C–O bond occurred. The catalyst was reusable and very stable under the present reaction conditions. When CTFs were applied to the catalytic oxidative cleavage of organosolv lignin, nearly 80% of β-O-4 ketone bonds of the oxidized lignin were converted, suggesting the potential of CTFs in lignin depolymerization.