The synthesized “sweet” ionic liquids comprising acesulfame anion proved to be effective antifeedants with designer physicochemical properties.

No abstract

This study demonstrates the utilization of naturally occurring nicotinamide (vitamin B 3 ) in the sustainable synthesis of organic salts with application potential as environmentally friendly agrochemicals. The designed ionic pairs, obtained with high yields, consisted of N-alkylnicotinamide cation and commercially available herbicidal anions: 2,4-dichlorophenoxyacetate (2,4-D) and 4-chloro-2-methylphenoxyacetate (MCPA). The study confirmed the strong influence of the length of alkyl chain in products on the physicochemical properties as well as the development of cornflower and oil-seed rape. The majority of tested salts showed significantly better herbicidal activity (by approx. 30−50%) compared to the reference herbicide. Furthermore, Nhexadecylnicotinamide 4-chloro-2-methylphenoxyacetate was significantly more effective than the commercial formulation in the dose−response test. Their negligible vaporization, multiple times lower than that of commonly used dimethylammonium salts, eliminates one of the greatest threats of currently applied plant protection agents. Additionally, the risk of product migration or bioaccumulation in the environment was assessed as extremely low.

Efficient use of herbicides for plant protection requires the application of auxiliary substances such as surfactants, stabilizers, wetting or anti-foaming agents, and absorption enhancers, which can be more problematic for environment than the herbicides themselves. We hypothesized that the combination of sulfonylurea (iodosulfuron-methyl) anion with inexpensive, commercially available quaternary tetraalkylammonium cations could lead to biologically active ionic liquids (ILs) that could become a convenient and environment-friendly alternative to adjuvants. A simple one-step synthesis allowed for synthesizing iodosulfuron-methyl based ILs with high yields ranging from 88 to 96% as confirmed by UV, FTIR, and NMR. The obtained ILs were found to possess several favorable properties compared to the currently used sodium salt iodosulfuron-methyl, such as adjustable hydrophobicity (octanol-water partition coefficient) and enhanced stability in aqueous solutions, which was supported by molecular calculations showing cation–anion interaction energies. In addition, soil mobility and volatility of ILs were more beneficial compared to the parental herbicide. Herbicidal activity tests toward oil-seed rape and cornflower revealed that ILs comprising at least one alkyl chain in the decyl to octadecyl range had similar or better efficacy compared to the commercial preparation without addition of any adjuvant. Furthermore, results of antimicrobial activity indicated that they were practically harmless or slightly toxic toward model soil microorganisms such as Pseudomonas putida and Bacillus cereus.

One of the most important aspects associated with the modern production of chemicals is sustainability. To teach students and young scientists to design their research in the spirit of sustainable development, students should be made accustomed to seeking solutions that are not only efficient and cost-effective but also safe and environmentally friendly. However, it is still a great challenge to select appropriate material for a lecture that, in addition to providing educational aspects, will simultaneously attract students' attention. Therefore, to make learning more accessible and inspiring, it is worth using known molecules with interesting properties, such as denatonium salts, as the main product of the developed sustainable process. In this particular project, lidocaine was alkylated with benzyl chloride in the presence of a catalyst and subsequently subjected to an ion exchange reaction. This path resulted in the formation of two organic salts, denatonium benzoate and denatonium saccharinate, which are considered the most bitter substances currently known to mankind. Additionally, their syntheses were optimized according to green chemistry principles, and subsequently, the structures of the products were identified via spectroscopic methods (FTIR and NMR spectroscopies). Finally, determination of basic physicochemical parameters (solubility in water and octanol−water partition coefficient), according to OECD guidelines, enabled the assessment of the potential impact of these compounds on the natural environment.