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DFT calculations at the LC-wHPBE/6-311++G(d,p) level found that the solvolysis of t-butyl chloride or bromide in water or alcohol has two paths: a frontside path and a backside path. The frontside path is a three-step reaction. The first step is to remove a halogen anion and generate the carbocation (CH3)3C+, and it follows the Lewis collision theory and needs to overcome a barrier Ea. The carbocation is the first active intermediate in the solvolysis. The second step is that the carbocation and two solvent molecules (CH3)3C+ + 2R–OH (R = H or alkyl) to complete a spontaneous termolecular electrophilic addition AE3, in which the carbocation is the electrophile, and the product is an σ-complex that it is the second active intermediate in solvolysis. The third step is the generation of the product through a spontaneous termolecular proton transfer Tp3 of the σ-complex. The backside path is a two-step reaction. The first step is a termolecular nucleophilic substitution SN3 of (CH3)3C–Cl or –Br + 2R–OH, the substitution follows the transition state theory and has to overcome an activition barrier ∆E*. The product is the same σ complex as in the frontside path. The second step is the termolecular proton transfer Tp3 of the σ complex to generate the target product also. Thus the Tp3 is a shared step in the two paths. The two paths contain three termolecular reactions, and the last solvent molecule is a catalyst. Both paths are a four-molecular solvolysis processes involving one molecule of the alkyl halide and three solvent molecules, and are weakly or very weakly endothermic reactions. High-resolution ESI–MS confirmed the presence of the two paths and the two active intermediates. Based on the results, a solvent-catalyzed four-molecular two-path solvolysis mechanism of (CH3)3C–Cl or –Br in water or alcohol proposed.

In the present study, liquid chromatography coupled to an Orbitrap mass spectrometer (HPLC–Q-Orbitrap MS) was used as an approach for identification and quantification of 113 drugs simultaneously in biological samples (whole blood/plasma/serum). Samples were prepared using liquid–liquid extraction conducted using a trizma/isopropanol/butyl chloride buffer system. Reversed-phase separation employing a column (50 × 2.1 mm) packed with 2.6-μm C18 particles was then performed under gradient elution with mobile phase composition consisting of acetic acid and aqueous-acetonitrile mixtures with the acetonitrile content ranging from 10 to 100% v/v. Compounds were detected with high-resolution MS operated in full scan mode having a mass accuracy

Furfural is only derived from lignocellulosic biomass and is an important chemical used in the plastics, agrochemical, and pharmaceutical industries. The existing industrial furfural production process, involving reaction and purification steps, suffers from a low yield and intensive energy use. Hence, major improvements are needed to sustainably upgrade the furfural production process. In this study, the conventional furfural process based on a continuous stirred tank reactor and distillation columns was designed and optimized from an actual aqueous xylose solution via a biomass pretreatment step. Subsequently, a reactive distillation (RD) and extraction/distillation (ED) configuration was proposed for the reaction and purification steps, respectively, to improve the process efficiency. RD can remove furfural instantly from the reactive liquid phase and can separate heavy components from the raw furfural stream, while the ED configuration with toluene and butyl chloride used as extracting solvents can effectively separate furfural from a dilute aqueous stream. The results showed that the hybrid RD-ED process using a butyl chloride solvent saves up to 51.8% and 57.4% of the total investment costs and total annual costs, respectively, compared to the conventional process. Furthermore, environmental impacts were evaluated and compared for all structural alternatives.

Background Lignocellulosic biomass is one of the most promising alternatives for replacing mineral resources to overcome global warming, which has become the most important environmental issue in recent years. Furfural was listed by the National Renewable Energy Laboratory as one of the top 30 potential chemicals arising from biomass. However, the current production of furfural is energy intensive and uses inefficient technology. Thus, a hybrid purification process that combines extraction and distillation to produce furfural from lignocellulosic biomass was considered and investigated in detail to improve the process efficiency. This effective hybrid process depends on the extracting solvent, which was selected based on a comprehensive procedure that ranged from solvent screening to complete process design. Results Various solvents were first evaluated in terms of their extraction ability. Then, the most promising solvents were selected to study the separation feasibility. Eventually, processes that used the three best solvents (toluene, benzene, and butyl chloride) were designed and optimized in detail using Aspen Plus. Sustainability analysis was performed to evaluate these processes in terms of their energy requirements, total annual costs (TAC), and carbon dioxide (CO2) emissions. The results showed that butyl chloride was the most suitable solvent for the hybrid furfural process because it could save 44.7% of the TAC while reducing the CO2 emissions by 45.5% compared to the toluene process. In comparison with the traditional purification process using distillation, this suggested hybrid extraction/distillation process can save up to 19.2% of the TAC and reduce 58.3% total annual CO2 emissions. Furthermore, a sensitivity analysis of the feed composition and its effect on the performance of the proposed hybrid system was conducted. Conclusions Butyl chloride was found to be the most suitable solvent for the hybrid extraction/distillation process of furfural production. The proposed hybrid sequence was more favorable than the traditional distillation process when the methanol fraction of the feed stream was

The formation of radical cations and radicals of thioamides (R) $$\mathbf{(NH_{2})}$$ CS, where R represents $$\hbox {CH}_{3}$$ in thioacetamide (TA) and $$\hbox {C}_{6}\hbox {H}_{5}$$ in thiobenzamide (TBA) in n-butyl chloride has been studied using pulse radiolysis technique. The radical cations of TA and TBA are observed in n-butyl chloride, and on their subsequent deprotonation, respective radicals are generated. In this study on thioamide solutions in n-butyl chloride, the transient species formed at $$1.2\,\upmu \hbox {s}$$ after the electron pulse exhibiting absorption maxima in 400 nm region are attributed to their radical cations. In the presence of 0.1 M ethanol ( $$\hbox {C}_{2}\hbox {H}_{5}\hbox {OH}$$ ), a radical cation scavenger, the absorbance values at corresponding peaks are reduced substantially, revealing the formation of their respective radical cations. Moreover, at a later time, the generation of radical species takes place through deprotonation of radical cations and also through direct reactions during electron pulse irradiation. The mechanisms for the formation of radical cations and radicals of these two thioamides under pulse radiolysis have been revisited in butyl chloride medium wherein the charge transfer reactions are more prominent. Results of quantum chemical calculation support the mechanistic explanation and provide information on the reactivity of parent molecules, and the charge distribution on radical cations and radicals species of thioamides.

Bulk free radical polymerization of the monomer series CH2 = C(CH3)C(O)OCH2CH3-nCln, n = 1, 2, 3, yields an unexpectedly crosslinked product with a crosslink density that increases with decreasing chlorine content of the respective monomer (n = 3

Excess molar volumes ( V m E ), excess molar enthalpy ( H m E ) and isothermal vapor-liquid equilibrium data for n-, sec- and tert-butyl chloride (A) + cyclohexane (B) systems were measured at 298.15 K. Excess molar Gibbs free energy ( G m E ) for these systems were calculated by Barker's method. The V m E and H m E for these mixtures follow the sequence: n- > sec- > tert-butyl chloride while it is reverse for G m E . Prigogine-Flory-Patterson theory (PFP) predicts the experimental V m E and H m E data for these systems quite well except for H m E of n-butyl chloride ( x A > 0.5 ) mixtures and tert-butyl chloride mixtures for x A 0.5 . The activity coefficients γ A and γ B of the components in binary (A+B) mixtures were also predicted by Singh and Maken activity coefficient model employing limited experimental activity coefficient data.

The photophysical properties of donor-acceptor based benzoxazoles were investigated by means of steady-state and time-resolved fluorescence techniques. Additionally, laser stimulated second-order optical effects (preliminary second harmonic generation (SHG) were studied. The studies show that the nitro-benzoxazole derivatives decorated with different alkylo/arylo amino groups dissolved in medium polar aprotic solvents: tetrahydrofuran and butyl chloride, exhibit dual fluorescence from the locally excited state (1LE) and a highly polar charge transfer (CT) state. Ambient-temperature time-resolved fluorescence investigations prove the bimodal kinetics of the excited-state electron transfer reaction 1LE→1CT. The lack of any CT emissions in cyclohexane and highly polar acetonitrile is presumably due to an efficient inter-system crossing process or fast deactivation of a low-lying CT state. In addition, strong CT properties inspired us to check a possibility to vary the absorption of the first UV–Vis maxima under influence of the external bicolour coherent laser light and the related optical second harmonic generation (SHG). The two coherent beams of the infrared Er:glass laser at 1540 nm/770 nm formed gratings in the photopolymer solidified chromophore. The performed experiments are compared with the theoretically calculated electronic parameters within the B3LYP DFT approach. The presented data open novel type of materials, allowing to operate its transparency using external IR laser light in the near IR spectral range.

The majority of commercial membrane units for large-scale natural gas sweetening are based on cellulose acetate (CA). However, the low selectivity and risk for and plasticisation affect adversely the performance of CA-based systems. Herein, we present a new class of CA-derived poly(ionic liquid) (PIL) as a thin film composite (TFC) membrane for CO2 separations. CA is modified with pyrrolidinium cations through alkylation of butyl chloride, substituting the hydroxyl group in the polymer backbone, and further anion exchange to bis(trifluoromethylsulfonyl)imide, P[CA][Tf2N]. The synthesised PIL material properties are extensively studied. The CO2 separation performance of the newly synthesised materials is evaluated by gravimetric gas sorption experiments, single gas time-lag experiments on thick membranes, and mixed-gas separation experiments on TFC membranes. The results are compared to the parent material (CA) as well as a reference PIL (poly(diallyldimethyl ammonium) bis(trifluoromethylsulfonyl)imide (P[DADMA][Tf2N])). The ideal CO2/N2 sorption selectivity of P[CA][Tf2N] is constant up to 10 bar. The single gas transport measurements in P[CA][Tf2N] reveal improved ideal CO2 selectivity for the CO2/N2 gas pair and increased CO2 permeability for the CO2/CH4 gas pair compared to the reference PIL. Mixed-gas permeation tests demonstrated that P[CA][Tf2N]-based membranes with a 5 µm thick selective layer has a two-fold higher CO2 flux compared to conventional CA. These results present CA modification into PILs as a successful approach promoting the higher permeate flows and improved process stability in a wide range of concentrations and pressures of CO2/N2 and CO2/CH4 gas mixtures.

This article is devoted to the analysis of the surface properties of polyester textile materials modified with the tetrafluoroethylene telomeres synthesized in acetone and butyl chloride in order to impart high hydrophobicity to the materials. The particularities of the morphology of the formed hydrophobic coatings in the case of the use of various solutions of tetrafluoroethylene telomeres have been demonstrated using atomic force microscopy (AFM). The dependencies of the characteristics of the hydrophobicity of the modified textile materials on the structure of the coatings have been analyzed. The resistance of the coatings to the operational impacts has been determined.

The novel functionalized ionic liquids based on imidazolium cation are synthesized and characterized by studying its 1 H, 13 C, and 31 P NMR and elemental analysis. These ionic liquids have been reported as a highly efficient catalyst for N -alkylation reaction of aniline with butyl chloride. The reaction was efficiently performed in ionic liquid as an environmentally benign solvent with good yields without transition metal.

A facile, rapid and efficient method for the preparation of dialkoxymethanes from dichloromethane with alcohols catalyzed by a Cu-NHC complex is reported. A variety of symmetrical dialkoxymethanes can be prepared under mild condition in excellent yields (up to 98%). The unsymmetrical ether is also obtained in 89% yield from the etherification of p- tolylmethanol and n -butyl chloride catalyzed by ICyCuCl complex at 80 °C. The reaction provides a new method for the preparation of dialkoxymethanes under mild conditions in excellent yields.

Gas chromatography (GC) hyphenated with nitrogen chemiluminescence detection (NCD) and quadrupole time-of-flight mass spectrometry (QTOFMS) was applied for the first time to the quantitative analysis of new psychoactive substances (NPS) in urine, based on the N-equimolar response of NCD. A method was developed and validated to estimate the concentrations of three metabolites of the common stimulant NPS α-pyrrolidinovalerophenone (α-PVP) in spiked urine samples, simulating an analysis having no authentic reference standards for the metabolites and using the parent drug instead for quantitative calibration. The metabolites studied were OH-α-PVP (M1), 2″-oxo-α-PVP (M3), and N,N-bis-dealkyl-PVP (2-amino-1-phenylpentan-1-one; M5). Sample preparation involved liquid-liquid extraction with a mixture of ethyl acetate and butyl chloride at a basic pH and subsequent silylation of the sec-hydroxyl and prim-amino groups of M1 and M5, respectively. Simultaneous compound identification was based on the accurate masses of the protonated molecules for each compound by QTOFMS following atmospheric pressure chemical ionization. The accuracy of quantification of the parent-calibrated NCD method was compared with that of the corresponding parent-calibrated QTOFMS method, as well as with a reference QTOFMS method calibrated with the authentic reference standards. The NCD method produced an equally good accuracy to the reference method for α-PVP, M3 and M5, while a higher negative bias (25%) was obtained for M1, best explainable by recovery and stability issues. The performance of the parent-calibrated QTOFMS method was inferior to the reference method with an especially high negative bias (60%) for M1. The NCD method enabled better quantitative precision than the QTOFMS methods To evaluate the novel approach in casework, twenty post- mortem urine samples previously found positive for α-PVP were analyzed by the parent calibrated NCD method and the reference QTOFMS method. The highest difference in the quantitative results between the two methods was only 33%, and the NCD method's precision as the coefficient of variation was better than 13%. The limit of quantification for the NCD method was approximately 0.25μg/mL in urine, which generally allowed the analysis of α-PVP and the main metabolite M1. However, the sensitivity was not sufficient for the low concentrations of M3 and M5. Consequently, while having potential for instant analysis of NPS and metabolites in moderate concentrations without reference standards, the NCD method should be further developed for improved sensitivity to be more generally applicable.

We investigated the etching effect of tertiary-butyl chloride (TBCl) during InP nanowire (NW) growth for the purpose of improving the tapering shape at high growth temperature. The vapor–liquid–solid method was performed by using 10-nm-diameter Au particles for NW growth. The InP NW length doubled when TBCl was supplied at the same flow rate as TMIn and decreased gradually with increasing TBCl flow, while the volume monotonically decreased. The TBCl effectively suppressed growth in the radial direction. We also systematically studied the dependence of NW length and volume on growth time, growth temperature, and TMIn flow rate with and without TBCl. The crystalline structure was apparently varied within our growth condition range. At high growth temperature and low TBCl flow rate, the NWs tended to have a wurtzite-based structure.

Tetrafluoroethylene (TFE) telomeres were synthesized in a butyl chloride solution using the radiation-chemical initiation of the reaction. The surface of a polyester material was modified with TFE telomeres to impart superhydrophobic properties to the fabric.

The aim of this study was to incorporate an alpha-olefin (1-hexene or 1-dodecene) in a high cis polybutadiene chain, using a neodymium versatate/diisobutylaluminum hydride/t-butyl chloride catalyst system. The influence of alpha-olefin on polymerization reaction and polymer characteristics, using different weight ratios of butadiene/α-olefin, was evaluated. The copolymers were characterized by SEC, FTIR, NMR, TGA and viscosimetric analysis. The thermal stability of the polymer tended to increase with incorporation of alpha-olefins, while its microstructure was not affected. The weight average molecular mass (Mw) tended to increase and the polymerization conversion tended to decrease with increasing alpha-olefins content. The copolymers showed a lower intrinsic viscosity than for the homopolymer. The results indicated that the alpha-olefins were incorporated in the polybutadiene chain.

GC with nitrogen phosphorus detection and HPLC with UV detection were used to determine midazolam (MDZ) levels in rabbit plasma following ocular and nasal administration. For GC with nitrogen phosphorus detection, the analyte was extracted from the plasma using a three-step liquid-liquid extraction including extraction with an isopropanol/butyl chloride mixture in an alkaline solution, followed by extractions with 1 M HCl, and finally with an alkaline solution of butyl chloride. The recovery of MDZ was dependent on the sample alkalization time prior to the final extraction. The procedure increased the recovery of MDZ up to 99.6%. Improved sample preparation led to a significant increase in the sensitivity of the determination by GC with nitrogen phosphorus detection. The achieved detection limit was 0.34 ng/mL, which is ten times lower than that obtained using HPLC with UV detection. The small plasma volume was another advantage of the GC with nitrogen phosphorus detection method (200 μL per assay). Both administration routes of the anesthetic (nasal and ocular) resulted in comparable plasma MDZ levels. Kinetic simulation of the MDZ plasma was performed for both administration routes.

PVDF microfiltration membranes were modified by γ-ray irradiation induced grafting polymerization of 4-vinyl pyridine (4-VP) and then quaternization by n -butyl chloride. The effects of grafting method (simultaneous irradiation, pre-irradiation/UV), grafting conditions (absorbed dose, UV irradiation time, and 4-VP concentration) and quaternization conditions (temperature, time, and concentration of n -butyl chloride) were investigated. It was found that, the grafting degree initially increases with the absorbed dose and then reaches a plateau. The optimal concentration of 4-VP is around 15 wt.%. The ion exchange capacity increases with quaternization temperature, time, and concentration of n -butyl chloride. After modification, the pores size, permeation flux, as well as elongation at break, of quaternized membrane decreases, while the retention coefficient, tensile strength and Young’s modulus increase apparently. Upon contacting with the membranes, the Escherichia coli concentration decreases gradually. It is the adsorption mechanism for the pristine membranes whereas contact-killing mechanism for the quaternized membranes. Simultaneous irradiation is more effective than pre-irradiation/UV in the improvement of antibacterial property of membranes.

Autoignition temperature (AIT) is indispensable information for safe handling and operation of flammable material. Typical applications of AIT in industry include classification of explosion-proof electric equipment and assessment of risk for potential leakage of hazardous chemical. Despite of its significance, in different data compilations, the discrepancies in reported AIT are appreciable, and an emergent need exists for investigating AIT of chemical substances through experimental approach before this information may be reliably attempted for industrial application. In this study the AITs of seven halogenated compounds were measured in compliance with the ASTM E659 test method. The AIT and ignition delay time determined from experiment for isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, pentyl bromide, chlorocyclohexane, and benzoyl chloride were (493.1 ± 9.9) °C/259.5 s, (244.0 ± 4.9) °C/35.9 s, (438.8 ± 8.8) °C/7.2 s, (252.0 ± 5.1) °C/58.0 s, (245.0 ± 4.9) °C/103.8 s, (255.8 ...

The kinetics of low-temperature (180–270 K) postradiation telomerization of tetrafluoroethylene in hexafluoroisopropanol has been investigated. The efficiency of the process is determined by the initial concentration of the monomer in the solvent and the dose of preliminary irradiation. It has been shown that the telomerization reaction proceeds via the radical mechanism during the devitrification of the system. Active centers that initiate the process and their yield at 77 K have been studied by the ESR technique. Some properties of the product telomers have been studied.

Hydrophobic coatings formed on a polyester fabric by treatment with telomeric solutions prepared by a radiation-chemical procedure in acetone and butyl chloride were studied by IR spectroscopy (MATIR), energy-dispersive analysis, and atomic force microscopy. The hydrophobic properties of the textile material were evaluated by procedures traditional for textile chemistry. Conditions determining the formation of a thin, highly hydrophobic, uniform, and flawless coating resistant to the effect of operation factors were suggested.

3H-Pyrrolo[2,1-a]isoindole-2,5-diones and isoindolo[2,1-a]quinoline-5,11-diones were synthesized by intramolecular cyclization of N-[2-oxo-3-(triphenyl-λ5-phosphanylidene)propyl]- and N-[2-(triphenyl-λ5-phosphanylidene)acetyl]phthalimides, respectively, in the presence of ionic liquid ([bmim][BF4], 10 mol %) as catalyst or under microwave irradiation.

The kinetics of the radiation-initiated telomerization of tetrafluoroethylene (TFE) in the solutions of telogens (butyl chloride, chloroform, methylene chloride, and carbon tetrachloride) at a constant monomer pressure in the reactor was studied. In the course of the Γ-irradiation of the reaction mixture, TFE telomers containing repeatedly soluble and insoluble fractions were formed. In chloroform, methylene chloride, and carbon tetrachloride, the rapidly occurring process of the synthesis of insoluble telomer made the main contribution to the total yield of products. For the solutions of TFE in butyl chloride, the rates of formation of soluble and insoluble telomers were almost the same. The average chain length and the thermal stability of the resulting telomers were evaluated.

Decomposition of hydrazinium pentafluoroaluminate under oxidative (F 2 ) conditions leads to aluminium(III) fluoride whose properties are highly dependent on the conditions used for synthesis. In the presence of anhydrous HF, which probably acts as a heat exchange agent, samples have high BET areas, whereas BET areas of samples prepared under gas–solid conditions are small. XPS data are consistent with the presence of Lewis acid centres but, more importantly, emphasise the importance of surface hydroxyl groups, particularly in high surface area compounds. Catalytic behaviour towards isomerisation of 1,1,2-trichlorotrifluoroethane and subsequent dismutations at moderate temperatures and towards room temperature dehydrochlorination of tert -butyl chloride has been demonstrated for some high BET samples; both reactions indicate that surface Lewis sites exist. Catalytic ability is inhibited by surface hydroxyl groups but is improved by prior fluorination of the surface with CCl 2 F 2 . Catalysis is inhibited also by the presence of ammonium fluoroaluminate, a by-product of the decomposition process. The [NH 4 ] + salt level can be reduced by washing with anhydrous HF.