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The reaction of 1-butylimidazole (1a) with aryl/alkoxy halides (2a–h) using a microwave solvent-free approach delivered imidazolium-based ILs (3a–h) in good yield. Some of them showed promising antibacterial and antifungal activities.

An efficient, convenient, and environmentally benign method for synthesis of novel (E)-3-aryl-1-(3-alkyl-2pyrazinyl)-2-propenone in aqueous micellar medium at room temperature has been developed. Initially, the reaction between 2-acetyl-3-methylpyrazine (1a; 1 mmol) and 4bromobenzaldehyde (2c; 1 mmol) was separately conducted with 10 mol % cationic quaternary ammonium surfactants (CQAS), namely, methyltrioctylammonium chloride (MTOAC), methyltrioctylammonium bromide (MTOAB), cetylpyridinium chloride (CPC), cetylpyridinium bromide (CPB), dodecyltrimethylammonium bromide (DTAB), and hexadecyltrimethylammonium bromide (CTAB). An 89.0% maximum yield was noted with DTAB due to higher a catalyzing effect on the reaction. The other surfactants used for the same reaction have produced only 50−86% yield. DTAB was found to be a most efficient catalyst because of the higher yield in the reaction. Therefore, applying DTAB, the various reaction conditions such as effect of concentration (2.5−20 mol %), temperature (rt-reflux), and reusability of aqueous micellar medium were investigated. Thus, the 15 mol % DTAB used for synthesis of a series (3a−3l) of compounds at room temperature produced a 78−94% yield. The method using DTAB allows for the preparation of a variety of aryl propenones with better yield and purities, making any further purification unnecessary. DTAB is also considered environmentally benign and may lead to developing a new option of synthesis in green chemistry. The structures were confirmed by FTIR, 1 H NMR, 13 C NMR, LCMS (Q-TOF), and elemental analysis.

Radical scavenging activity (RSA) of chloro and methyl substituted benzylamine derivatives (BADs) has been studied using 1, 1-diphenyl-2-picrylhydrazyl free radical (DPPH•) through spectrophotometric and physicochemical techniques at T = (298.15, 303.15 and 308.15) K. New experimental data on the density, sound velocity, isentropic and apparent molal compressibility of selected BADs + DPPH • solutions as a function of temperature and concentration are reported. The results are discussed with regards to structure-activity relationship (SAR) principles of BADs. The relative deviations in RSAs varied with structural potentials of BADs which were analyzed by making a comparative study for both the spectrophotometric and physicochemical results.