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The non-fluorescent 9-nitrobenzo[b]quinolizinium is readily reduced by nitroreductase to a fluorescent reaction product. The resulting light-up effect enables the selective detection of nitro-reductase activity in vitro and in Escherichia coli bacterial cultures.

Red mud and iron tailings are representative solid wastes in China, which have caused serious environmental pollution and potential harmful risk to people. Based on the alkali characteristic of Bayer red mud and natural fine-grained feature of iron tailings, these two solid wastes were used as raw materials to prepare alkali-activated cementitious mortar (AACM). The microstructure of C-A-S-H gel, pore structure characteristics, environmental impact and economic potential of this AACM were investigated. The results show that C-A-S-H gel was mainly composed of SiQ3 structure in the 28-day cured AACM. The relative content of SiQ4 structure increased while that of SiQ2 structure decreased as the hydration time advanced from 7 to 28 days, resulting in the increase of relative bridge oxygen value by 11.02%. The pores in the AACM sample accounted for 6.73% of the total volume, and these pores were not connected. The pore distribution was relatively uniform, which supported the good development of mechanical strength for AACM. This research elucidates the formation mechanism of C-A-S-H gels in the Bayer red mud–iron tailings-based AACM. In addition, the lower embodied carbon and material cost demonstrate that the prepared AACM has great environmental benefit and certain economic potential.

Bridged nitrogen bicyclic skeletons have been accessed via unprecedented site- and diastereoselective orthogonal tandem catalysis from readily accessible reactants in a step economic manner. Directed Pd-catalyzed gamma-C(sp3)-H olefination of aminocyclohexane with gem-dibromoalkenes, followed by a consecutive intramolecular Cu-catalyzed amidation of the 1-bromo-1-alkenylated product delivers the interesting normorphan skeleton. The tandem protocol can be applied on substituted aminocyclohexanes and aminoheterocycles, easily providing access to the corresponding substituted, aza- and oxa-analogues. The Cu catalyst of the Ullmann-Goldberg reaction additionally avoids off-cycle Pd catalyst scavenging by alkenylated reaction product. The picolinamide directing group stabilizes the enamine of the 7-alkylidenenormorphan, allowing further product post functionalizations. Without Cu catalyst, regio- and diastereoselective Pd-catalyzed gamma-C(sp3)-H olefination is achieved., info:eu-repo/semantics/published

The reaction between methylammonium iodide ( $${\text{MAI}}$$ $$({\text{MA}} = {\text{CH}}_{3} {\text{NH}}_{3}^{ + } )$$ ) and antimony sulfoiodide ( $${\text{SbSI}}$$ ) in reflux conditions results in the formation of a 2D-layered perovskite phase, methylammonium antimony iodide ( $${\text{MA}}_{3} {\text{Sb}}_{2} I_{9}$$ ). X-ray diffraction $$\left( {{\text{XRD}}} \right)$$ and $${\text{UV}} - {\text{Vis}}$$ spectroscopy confirm that in reflux conditions, the reaction between $${\text{MAI}}$$ and $${\text{SbSI}}$$ in a 2:7 molar ratio (MR(2:7)) obtains the $$2D$$ -layered $${\text{MA}}_{3} {\text{Sb}}_{2} I_{9}$$ lead-free perovskite phase as the main product. The MR(2:7) $${\text{~MAI}}$$ - $${\text{SbSI}}$$ reaction product in a carbon matrix in lateral electrode configuration exhibits a relatively high difference between light and dark current $$\left( {I_{{{\text{light}}}} - I_{{{\text{dark}}}} } \right)$$ of ~ 55 µA at 1 V applied bias voltage. The better photoresponse for the MR(2:7) $${\text{MAI}}$$ - $${\text{SbSI}}$$ reaction product in the presented device configuration indicates that the lead-free 2D-layered perovskite structure ( $${\text{MA}}_{3} {\text{Sb}}_{2} I_{9}$$ ) found assistance from the carbon materials for improved photogenerated charge carrier harvesting.

MqnD catalyzes the conversion of cyclic dehypoxanthine futalosine (6) to 5,8-dihydroxy-2-naphthoic acid (7) and an uncharacterized product. This study describes a chemoenzymatic synthesis of 6. This synthesis achieved a 2-fold yield enhancement by using titanium(III) citrate as the reducing agent and another 5-fold yield enhancement using a fluorinated analogue of dehypoxanthine futalosine (5) that was converted to 6 by an ipso substitution mechanism. This synthetic route enabled the synthesis of 6 in sufficient quantity to identify the second reaction product and to determine that the MqnD-catalyzed reaction proceeds by a hemiacetal ring opening-tautomerization-retroaldol sequence.

As a principal compound of cinnamon essential oil, cinnamaldehyde has been used as a marker for the quality control of cinnamon and its essential oil. During the HPLC analysis, a reaction product was observed in methanol solution of cinnamaldehyde reference standard. This product was isolated and identified to be cinnamaldehyde dimethyl acetal based on the spectroscopic analysis. Although dimethylacetalization of cinnamaldehyde in MeOH has been recorded in many literatures, this is the first report about this reaction in normal analysis procedure. Further studies suggested that this reaction could be affected by many parameters, including cinnamaldehyde concentration, storage temperature, and light illumination. Those results suggested the stock solution of cinnamaldehyde reference standard should not be prepared with methanol, and the extraction procedure by heating the sample with methanol might accelerate the acetalization of cinnamaldehyde. The use of methanol during the analysis of cinnamaldehyde should be carefully considered.

A new hemisynthetic oleanane saponin: 4',2",3",4",6"-penta-O-acetyl-6'-O- methyl-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl oleanolic acid (2) was obtained after acetylation and methylation reaction on 3-O-β-D- glucopyranosyl-(1→2)-β-D-glucuronopyranosyl oleanolic acid (1). Its structure was established by extensive analysis of 1D-(1H, 13C), 2D-(COSY, HSQC and HMBC) NMR data in conjunction with mass spectrometry (HR- TOFESIMS). The evaluation of antimicrobial activities using microdilution method showed that, reaction product (2) presented the lowest values of MIC against E. coli (MIC = 16 μg/mL), S. aureus (MIC = 8 μg/mL), C. tropicalis (MIC = 16 μg/mL) C. albicans (MIC = 8 μg/mL) compare to the substrate (1) against the same microbial strains: E. coli (MIC = 32 μg/mL), S. aureus (MIC = 16 μg/mL), C. tropicalis (MIC = 32 μg/mL), C. albicans (MIC = 16 μg/mL). These results indicate that, acetylation and methylation reactions of compound 1 increase its antimicrobial activities against the tested microorganisms.

An algorithm for solving an optimal control problem with terminal constraints is developed. The optimal control problem with terminal constraints and constraints on the control parameter is formulated. To solve the problem, a numerical algorithm based on the penalty method and genetic algorithms is described. A computational experiment is performed for the synthesis reaction of phthalic anhydride in order to get the maximum yield of the reaction product under terminal constraints. The optimal temperature regime and optimal concentrations of reagents are obtained.

Pyrolysis of a mixture of 2,5-difluoro-3,4,6-trichlorobenzenethiol with tetrafluoroethylene leads to 2,2,3,3,4,7-hexafluoro-5,6-dichloro-2,3-dihydrobenzo[b]thiophene (the major reaction product) along with 2,2,3,3,4,6-hexafluoro-5,7-dichloro-2,3-dihydrobenzo[b]thiophene. Schemes of their formation with the participation of intermediate radicals are proposed. Oxidation of a mixture of the synthesized compounds gave 2,2,3,3,4,7-hexafluoro-5,6-dichloro-2,3-dihydrobenzo[b]sulfane-1,1-dioxide and 2,2,3,3,4,6-hexafluoro-5,7-dichloro-2,3-dihydrobenzo[b]sulfane-1,1-dioxide.

A number of models of the polymerase chain reaction have been suggested to date with the aim of gaining exact quantitative estimates for reaction products. These models usually identify the reaction product kinetics with a kinetics of fluorescence reporter. Here, a model of polymerase chain reaction is suggested in which the results of the reaction are detected using an intercalating dye. Simulation data indicate a significant discrepancy between the reaction product kinetics and the fluorescent signal from a bonded intercalator.

The catalyst layer (CL) is a critical component that determines the performance of proton exchange membrane fuel cells, and the production process of CL is important issue. A CL is fabricated from a catalyst ink mixed with platinum-supported carbon (Pt/C), ionomer solution, and a solvent. When the catalyst ink is coated on the sheet and dried, the CL is formed. By transferring the CL to the membrane, catalyst coated membrane can be made [1]. The process from the initial characteristics of the catalyst ink to the drying process determines the structure of CL and dominates the characteristics of the fuel cell. Thus, quality control of the catalyst ink is important to form a high performance and uniform CL [2]. We have reported that alcohol oxidation reaction and condensation reaction, as catalyzed by platinum, occurred in the catalyst ink fabrication process [3]. Several reaction products, aldehydes, acids, and esters, were detected by gas chromatography mass spectrometry (GC/MS) [4]. In this study, concentration of those reaction products were measured quantitatively, and the effect of those reaction products on the catalyst ink property and CL quality was investigated. Catalyst ink was prepared by using the mixture of water and ethanol as a dispersant. We used platinum catalyst supported on carbon black and Nafion dispersion. The solvent was composed of ethanol and water. The weight ratio between ethanol and water was set to 46:54 or 60:40. Nonvolatile content was 10 wt%. Weight ratio between Nafion and the carbon support was 0.75. As a mixing process, a high-speed rotary type mixer was used, and mixing time was set to 10 min. The quantitative concentration of reaction products in each ink were analyzed by GC/MS. After concentration measurement, CL was fabricated using each ink. The crack formation was observed, and the correlation with the initial composition of the ink and the concentration of the reaction product was investigated. As a result of GC/MS, several reaction products (acetaldehyde, acetic acid, and ethyl acetate) were detected in the catalyst ink. Table 1 shows quantitative concentration of reaction products. Comparing the both catalyst inks, the concentration of acetaldehyde increased remarkably when the ethanol concentration increased. CLs were fabricated with using those catalyst inks and observed by microscope (Figure 1). There was no crack in the low ethanol concentration ink, and cracks occurred in the high ethanol concentration ink. Those results suggest that acetaldehyde may be a factor in causing cracks in the CL. To clarify the effect of acetaldehyde, acetic acid, and ethyl acetate on the crack formation in the CL, each substance was artificially added to the low ethanol concentration catalyst ink. In actual catalyst ink, it is considered that ethanol reacts to produce a reaction product. Therefore, in the modified catalyst ink, the amount of ethanol was reduced according to the amount of added substance. The CL was fabricated by using those catalyst ink and the observation results were shown in Figure 2. When the same amount of acetaldehyde contained in the high ethanol concentration catalyst ink was added, many cracks were generated in the CL. Several cracks occurred when ethyl acetate was added, but the required amount was significantly higher than the ethyl acetate concentration detected in the actual catalyst ink. No cracks were generated even if a large amount of acetic acid was added to the catalyst ink. These results indicate that the acetaldehyde is a factor of crack in the CL. It is considered that when the generated acetaldehyde exceeds a certain concentration in the catalyst ink, crack is caused in the CL. Acknowledgment: This study is based on the results obtained from a project commissioned by the New Energy and Industrial Technology Development Organization (NEDO). References: T. Suzuki, ECS Transactions, 75(14), 423-434 (2016). S.J. Shin et al., J. Power Source 106, 146-152 (2002). S. Uemura et al., J. Electrochem. Soc., 166-2, F89 (2019). S. Uemura et al., ECS Trans., 92-8, 183-187 (2019). Figure 1

Proline-rich antimicrobial peptides (PrAMPs) are promising lead compounds for developing new antimicrobials, however their narrow spectrum of action is limiting. PrAMPs kill bacteria binding to their ribosomes and inhibiting protein synthesis. In this study, 133 derivatives of the PrAMP Bac7(1-16) were synthesized to identify the crucial residues for ribosome inactivation and antimicrobial activity. Then, five new Bac7(1-16) derivatives were conceived and characterized by antibacterial and membrane permeabilization assays, by X-ray crystallography and molecular dynamics simulations. Some derivatives displayed broad spectrum activity, encompassing Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa and Staphylococcus aureus. Two peptides out of five, acquired a weak membrane-perturbing activity, while maintaining the ability to inhibit protein synthesis. These derivatives became independent of the SbmA transporter, commonly used by native PrAMPs, suggesting that they obtained a novel route to enter bacterial cells. PrAMP-derived compounds could become new-generation antimicrobials to combat the antibiotic-resistant pathogens.

A thermodynamic analysis is performed of the patterns of steam conversion of natural gas at temperatures of 300–600°C, pressures of 0.1–4 MPa and H2O : C molar ratios of 0.8‒1.2. Under these conditions, the reaction product is methane–hydrogen mixtures with hydrogen concentrations of 10–30 vol %. A rise in temperature, molar ratio Н2О : С, and a decrease in pressure contribute to an increase in the concentration of hydrogen in the reaction products. The thermodynamic boundaries of the process with no carbonization of the catalyst are determined. Experiments are performed to obtain methane–hydrogen mixtures from methane with an output concentration of 15–35 vol % hydrogen on industrial Ni-CrOx-Al2O3 catalyst at 325–425°C, a H2O : C molar ratio of 0.8–1.0, and atmospheric pressure. It is shown that under these conditions, the process proceeds without the formation of carbon on the catalyst.

The current work reports the formation of triangular pyramidal pattern on c-plane sapphire substrate by the sulfuric-acid wet etching process. The corner-up Al2(SO4)3 wet-etching reaction product f...

Recently, ZnO-based gas sensors have been successfully fabricated and widely studied for their excellent sensitivity and selectivity, especially in CO detection. However, detailed explorations of their mechanisms are rather limited. Herein, aiming at clarifying the sensing mechanism, we carried out density functional theory (DFT) calculations to track down the CO adsorption and oxidation on the ZnO( 10 1 ¯ 0 ) and ( 11 2 ¯ 0 ) surfaces. The calculated results show that the lattice O of ZnO( 10 1 ¯ 0 ) is more reactive than that of ZnO( 11 2 ¯ 0 ) for CO oxidation. From the calculated energetics and structures, the main reaction product on both surfaces can be determined to be CO2 rather than carbonate. Moreover, the surface conductivity changes during the adsorption and reaction processes of CO were also studied. For both ZnO( 10 1 ¯ 0 ) and ( 11 2 ¯ 0 ), the conductivity would increase upon CO adsorption and decrease following CO oxidation, in consistence with the reported experimental results. This work can help understand the origins of ZnO-based sensors’ performances and the development of novel gas sensors with higher sensitivity and selectivity.

Heating of a solution of [(Dpp-bian)GaH2] (I) (Dpp-bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) in pyridine leads to elimination of a hydrogen atom and reduction of the diimine ligand to dianion, resulting in the complex [(Dpp-bian)GaH(Py)] (II). The reaction of I with 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (i-Pr2ImMe) is accompanied by a similar process, with the reaction product being identified as [(Dpp-bian)GaH(i-Pr2ImMe)] (III). Diamagnetic derivatives II and III were characterized by 1H NMR spectroscopy. The molecular structure of compound II was established by X-ray diffraction (CIF file CCDC no. 1973549).

The reaction of cyanothioacetamide with ethoxymethylenemalonate and triethylamine in ethanol upon heating is non-selective and leads to the formation of a mixture of triethylammonium 1,5-diamino-2,4-dicyano-5-thioxopenta-1,3-diene-1-thiolate and triethylammonium 6-oxo-3-cyano-5-ethoxycarbonyl-1H-pyridin-2-thiolate with a predominance of the latter. When treating with primary amines and 37% formalin in boiling aqueous alcohol, the reaction product gives only 4-(1,3,5-thiadiazinan-2-ylidene)-2-(3,4-dihydro-2H-1,3,5-thiadiazin-6-yl)pent-2-enedinitrile instead of the expected pyrido[2,1-b][1,3,5]thiadiazine derivatives. Triethylammonium 6-oxo-3-cyano-5-ethoxycarbonyl-1H-pyridin-2-thiolate does not react under these conditions.

Conjugates of terpenoids with 1,3,5-trisubstituted pyrazoles were synthesized by the cross-coupling of methyl 16-(2-chloro-2-oxoacetyl)labdatrienoate with terminal arylacetylenes via the Castro—Stephens reaction and heterocyclization of arylalkyne-1,2-diones with arylhydr-azines. The structure of one reaction product was established by X-ray diffraction. The conditions for the formation of furanolabdanoid arylalkyne-1,2-diones were found. The newly synthesized pyrazoles exhibit analgesic activity in a model of chemical irritation.

Introduction. The chlorination reaction in the synthesis of the substance of bendamustine hydrochloride is a complex process. The presence of active adverse reactions makes scaling difficult.Aim. Improving the performance of the technology for producing bendamustine ethyl ester in a flow microreactor.Materials and methods. A series of experiments was carried out to carry out the chlorination stage in the synthesis of bendamustine hydrochloride in a flow microreactor with various concentrations in the initial reagent solutions.Results and discussion. Experimental work was carried out to increase the productivity of the technology for the preparation of bendamustine ethyl ester (4-{[5-[bis(2-chloroethyl)amino]-1-methylbenzimidazol-2-yl}butanoic acid ethyl ester) by increasing the concentration of the starting reagents in the reaction mass. The conditions for conducting the chlorination reaction in the synthesis of bendamustine hydrochloride have been optimized, and possible ways to further increase productivity have been analyzed. The effect of changes in the concentration of reagents in the initial solutions and flow rates of reagent solutions on the final reaction product was studied.Conclusion. The optimal concentrations of reagents in the initial solutions were selected, allowing to increase the productivity of the flow microreactor with a volume of 137 mL to an equivalent level of a 100 liter capacitive reactor.

Mechanical activation (MA) of a binary mixture of titanium and nickel in an energy-intensive mill with the further high-temperature synthesis of titanium nickelide TiNi is experimentally and theoretically studied. The stage of mechanical pre-treatment of powders is found to contribute to the formation of layered particles of mechanocomposites with a developed interface and an active internal structure, which intensify the formation of reaction product during synthesis. Theoretical data are in good agreement with experimental data.

This study was aimed to find out a simple, sensitive and rapid spectrophotometric method for determination of salbutamol sulfate (SAL). The suggested method was based on the oxidative-coupling reaction of SAL with potassium iodate coupled with 4-amino-5-isopropyl-1-methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (AMP). The formed red colour of the reaction product was measured at a maximum absorption wavelength of 499 nm against the blank solution. It was obeyed to Beer-Lambert's law over the concentration ranged of 2–32 μg mL−1 with a molar absorptivity of 9.165 × 103 L mol−1 cm−1. The suitability of the proposed method for determination of SAL in the presence of some interfering species was studied. The method revealed high sensitivity for determination of the selected drug. The percentage recoveries were in the range from98.8 to 100.4% with relative standard deviation less than 0.3%. The developed method was validated according the current ICH guidelines (ICH guidelines, 2005). Promising results using the proposed spectrophotometric method were recorded for determination of SAL in its pure form and pharmaceutical formulations. Keywords: Salbutamol sulfate, AMP reagent, Method validation, Oxidative coupling reaction, Spectrophotometry

10 pags., 4 figs., 2 tabs., Rapid reactions of carboxylic acids with Criegee intermediates provide efficient gas phase removal processes and are proposed to trigger the formation of new molecular compounds, which are implicated in the growth of atmospheric aerosols. The new adducts formed in these reactions are known as hydroperoxide esters and are predicted to be condensable, with lower vapor pressures than the reactants. We report here the direct detection of hydroperoxyethyl formate (HOOCH(CH3)OCHO) formed in the gas phase reaction between the methyl substituted Criegee intermediate, CH3CHOO, and formic acid. Two different isomers of this hydroperoxide ester have been observed using the combination of pulsed Fourier-transform microwave spectroscopy with isotopic substitution experiments and high-level quantum chemical calculations. The identification of hydroperoxyethyl formate as the main nascent product of the CH3CHOO and HCOOH reaction differs from previous results that reported the formation of vinyl hydroperoxide as the reaction product of this reaction., This research was supported by the Ministry of Science and Technology of Taiwan under Grant Nos MOST 104-2113-M-009-020 (Y. E.) and MOST 105-2811-M-009-026 and 106-2811-M-009- 023 (C. C.).

Bitterness is a well-known aversive taste that can negatively impact consumer’s acceptance. The aim of this study was to investigate the generation of bitter blocker compounds derived from the bitter dietary phenolic compound epigallocatechin gallate (EGCg) through the Maillard reaction. Reaction models were investigated using different reaction variables (temperature, time, moisture, nature of sugars and amino acids, and reactants molar ratio) to obtain different phenolic-Maillard reaction products. Isotope labelling experiments using carbon labelled sugars were performed to identify the reaction products and compare the different reaction models. The main resulting reaction products were further isolated and purified for sensory analysis and accurate identification purposes to discover bitter blockers. A total of fourteen isolated reaction products were identified by accurate mass spectrometry analysis (HRMS) and nuclear magnetic resonance (NMR). Those reaction products were evaluated by sensory analysis through 2-AFC test comparisons and bitterness intensity ratings to determine their bitterness modulation properties. Two reaction products were found to significantly decrease the bitterness perception of caffeine bitter samples. The optimised Maillard reaction conditions to produce those bitter blockers were further described to provide new knowledge and insight regarding the generation of bitter blocker compounds during food processing.

The outcome of reaction of sodium N-benzylideneglycinate containing water in its crystal lattice with dialkyl chlorophosphites depends on the mode of addition of the latter. Upon the simultaneous mixing of the reactants, 1,4-bis[α-(dialkoxyphosphoryl)benzyl]piperazine-2,5-diones are formed from two molecules of each reactant. With the slow addition of dialkyl chlorophosphite, the main reaction product is 2-{3-[α-(dialkoxyphosphoryl)benzyl]-5-oxo-2-phenylimidazolidin-1-yl}acetic acid (‘1: 2 adduct’), its formation comprising 1,4-migration of dialkoxyphosphoryl moiety.

The reaction mechanism of the formation of hybrid oligomers based on complexes compounds of metal and oligophenylene is considered. The structure of compounds formed in such a reaction is determined. The effect of the addition of dimethyl sulfoxide on the increase in the yield of the main reaction product was found, and a mechanism of this effect was proposed, based on the change in the conformational features of oligophenylene in the synthesis process. The produced oligomers are promising as binders for composites of superhard materials.

Reaction of 3-formylchromones and triacetic acid lactone proceeds with retention of the chromone skeleton and cyclization into pyrano[3′,4′:5,6]pyrano[2,3-b]chromene system. The crystal structure of the reaction product from unsubstituted 3-formylchromone has been determined from X-ray data. Other chromone analogues bearing CO2H, CO2Me and CN substituents react with triacetic acid lactone affording an o-hydroxychalcone heteroanalogue, pyrano[3,2-c]chromene and chromeno[2,3-b]pyridine derivatives, respectively.

Electrolyte decomposition of lithium-ion battery as a consequence of thermal stress was investigated in Part 1 of this two-part study. The focus of Part 2 is on the influence of the battery cell op...

The invention relates to curable non-isocyanate polyurethane coating compositions which is the reaction product of a polycarbamate resin and a dialdehyde. The invention also relates to methods of making and using the curable coating compositions of the invention. The invention also relates to objects coated with the curable coating composition of the invention

The effect of micromonoclinic ZrO2 addition on properties of CaO-based refractories was investigated in our work. Zero, 5 wt%, 10 wt%, and 15 wt% micromonoclinic ZrO2 powders were added into CaO-MgO (CaO-based) refractories. The obtained results indicated that with the introduction of micromonoclinic ZrO2, the density increased slightly after heated at 1600 °C for 3 h. The results indicated that the density and mechanical properties of the samples were improved after introducing micromonoclinic ZrO2. The hydration resistance of the samples was improved with appropriate proportion of ZrO2. However, excessive ZrO2 damaged the hydration resistance of the samples. The influence of monoclinic ZrO2 on the samples was mainly caused by CaZrO3, the reaction product of CaO and ZrO2. The details of the CaZrO3 effects on the samples were discussed in this paper. Besides, based on the experiment results, CaO-based crucible was prepared and used in desulfurization. The desulfurization effects were compared with desulfurizer: Al. Desulfurizer reduced the content of [O] and [S] in the alloy obviously.

Although teaching laboratories offer students the opportunity to act and think like chemists, in many cases students simply follow written procedures to generate predetermined outcomes. In recent years, there has been a movement toward inquiry-, problem-, and discovery-based learning. In a similar vein, the first-semester introductory organic chemistry laboratory curriculum at the University of Michigan was recently overhauled, informed by the strategies of meaningful learning. The new course consists of three interconnected modules, and we present herein the second module, which focuses on liquid–liquid extraction (LLE). In the first week, students learn how to perform LLE by designing their own separation of a dye mixture, gaining an understanding of how the solution pH impacts molecular structure and solubility. In the second week, they practice using LLE by designing a separation method to remove a pollutant from water, and then, in the third week, they apply LLE to isolate a reaction product. We assessed student learning through a writing assignment at the end of the three-week module. We also assessed how the overall course affects student understanding of LLE concepts and their confidence in the lab. Our findings suggest that this learn, practice, apply approach for teaching LLE leads to modest learning gains and increased confidence.