A metal-free and cost-effective synthesis protocol has been initially proposed for the construction of CF3-containing oxindoles via the direct oxidative trifluoromethylation of activated alkenes with Langlois' reagent (CF3SO2Na). The present methodology, which utilizes very cheap CF3 reagent and a simple oxidant, provides a convenient and practical approach to CF3-containing oxindoles with a wide variety of functional groups.

The solid−liquid equilibrium for quizalofop-p-ethyl in 12 solvents (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, N,N-dimethylformamide (DMF), acetone, acetonitrile, ethyl acetate, 1,4-dioxane, toluene, and 1-hexane) was measured by using a static equilibrium method at temperatures T = 273.15−313.15 K under a pressure of 101.2 kPa. The results show that the solubility in those 12 monosolvents increases with increasing temperature. At a given temperature range, they gradually decrease in the following order: 1,4-dioxane > acetonitrile > DMF > toluene > acetone > ethyl acetate > 1-butanol > 1-propanol > 1-hexane > 2-propanol > ethanol > methanol. Moreover, a modified Apelblat model, λh model, Wilson model, and NRTL model were used to correlate the experiment values. Compared with the results of the above models, the calculated values provided good results with the experimental data. Consequently, the values of root-mean-square deviation (RMSD) and relative average deviation (RAD) were no more than 4.57 × 10 −4 and 2.29%, respectively. Furthermore, the thermodynamic properties of quizalofop-p-ethyl in monosolvents were calculated. From the analysis results, the dissolution process of quizalofop-p-ethyl was a spontaneous and entropy-driven process. The experimental solubility and the models in this study could be helpful in the application in the field of purification and recrystallization.

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The solubilities of three antofloxacin salts (antofloxacin hydrochloride, antofloxacin sulfate, and antofloxacin succinate) in six organic solvents, including methanol, ethanol, n-propanol, n-butanol, acetonitrile, and N,N-dimethylformamide (DMF), were determined experimentally over a temperature range from 273.15 to 318.15 K under 101.3 kPa. Within the temperature range studied, the solubility of these three compounds in the solvents increased with a rise of temperature. The solubility values of antofloxacin hydrochloride in these six solvents obey the following order: (methanol, DMF) > n-butanol > ethanol > n-propanol > acetonitrile. For the systems of antofloxacin sulfate + solvents, it ranked as DMF > methanol > ethanol > acetonitrile > n-propanol > n-butanol. While for antofloxacin succinate + solvents, the order of the data from high to low is DMF > methanol > n-butanol > n-propanol > ethanol > acetonitrile. The solubility data obtained for these three compounds in the studied solvents were correlated by using the modified Apelblat and λh equations. The maximum values of root-mean-square deviation (RMSD) and relative average deviation (RAD) were 3.3 × 10 −5 and 4.06%, respectively. Generally, the RAD values acquired with the modified Apelblat equation were smaller than λh equation for a certain solvent. The two thermodynamic models were all acceptable for the systems of these three compounds in these solvents. The obtained solubility values would be very helpful for drug application of antofloxacin hydrochloride, antofloxacin sulfate, and antofloxacin succinate.

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