The increasing limitations regarding the applied amounts of plant protection make hybrid ionic liquids an interesting class of compounds belonging to the III generation ILs.

Novel ionic liquids with cations based on alkyl derivatives of 1,4-diazabicyclo[2.2.2]octane (DABCO) and an anion derived from naturally occurring pelargonic acid possessed double biological functions: herbicidal and deterrent activity.

The desirable properties of ionic liquids (ILs) enable their use in various branches of chemistry, through a wide range of applications, e. g. as organic electrolytes. In the present study, an efficient two‐step method was developed for the synthesis of long‐chain ionic liquids with alkyl derivatives of DABCO as cations and bis(trifluoromethane)sulfonimide as anions. ILs obtained with high yields (≥91 %) were solids with melting points that increased with the rise in the number of carbon atoms of the alkyl substituent in the bicyclic cation. The structure of the compounds was confirmed by spectroscopic methods and elemental analysis. All compounds were soluble in the main solvents except water and hexane. The solubility in organic solvents such as acetonitrile allowed the use of synthesized ILs in electrochemical capacitors. Electrochemical tests revealed that the ILs enhanced the conductivity of organic electrolytes. This phenomenon improved the cyclability and reduced the internal resistance of the electrochemical capacitors.

New synthesis of 1-alkyl-1H,1′H-2,2′- bibenzo[d]imidazoles 3 by alkylation of a disodium derivative of 1H,1′H-2,2′-bibenzo[d]imidazole 2a with alkyl halides is proposed. It is noteworthy that 1,1′-dialkylated byproducts 4 are formed in yields of <5%. The structure of all obtained compounds has been confirmed by 1H NMR, 13C NMR, and HRMS or elemental analysis.