1,3-Bis(2,4,6-trimethylphenyl)imidazolium chloride is reduced electrochemically and chemically to produce a nucleophilic carbene, namely 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene. The carbene was also shown to be compatible with and persistent in the ionic liquid tetradecyl(trihexyl)phosphonium chloride.

Phosphonium ionic liquids (PhosILs), most notably tetradecyl(trihexyl)phosphonium decanoate (PhosIL-C(9)H(1)9COO), are solvents for bases such as Grignard reagents, isocyanides, Wittig reagents (phosphoranes), and N-heterocyclic carbenes (NHCs). The stability of the organometallic species in PhosIL solution is anion dependent. Small bases, such as hydroxide, react with the phosphonium ions and promote C-H exchange as suggested by deuterium-labeling studies. A method to dry and purify the ionic liquids is described and this step is important for the successful use of basic reagents in PhosIL. NHCs have been generated in PhosIL, and these persistent solutions catalyze organic transformations such as the benzoin condensation and the Kumada-Corriu cross-coupling reaction. Phosphoranes were generated in PhosIL, and their reactivity with various organic reagents was also tested. Inter-ion contacts involving tetraalkylphosphonium ions have been assessed, and the crystal structure of [(n-C(4)H(90)(4)P][CH(3)CO(2).CH(3)CO(2)H] has been determined to aid the discussion. Decomposition of organometallic compounds may also proceed through electron-transfer processes that, inter alia, may lead to decomposition of the IL, and hence the electrochemistry of some representative phosphonium and imidazolium ions has been studied. A radical derived from the electrochemical reduction of an imidazolium ion has been characterized by electron paramagnetic resonance spectroscopy.

Either light or electricity can be used to trigger the reversible cyclization reactions of three bis(N‐methylpyridinium)dithienylethene derivatives that differ from each other by the presence of either thiophene rings or methyl groups at the two carbon atoms of the photoresponsive hexatriene system involved in forming the new C–C bond. All three derivatives undergo ring‐closing isomerization reactions when irradiated with UV light (365 nm) or when electrochemically reduced (–1.0 V). All three derivatives can also be ring‐opened by irradiating them with visible light (> 490 nm) or by electrochemically oxidizing them (+1.5 V). The presence of additional thiophene rings attached to the two C2 ring positions of the dithienylethene (DTE) backbone enhances the electrochromic behavior, while methyl groups in these positions results in improved photochromic performance. The nature of these groups also greatly affects the thermal properties of the compounds in their ground states. Replacing each methyl group at the C2 ring positions with a thiophene ring systematically lowers the activation energy of spontaneous ring‐opening by 8 kJ mol–1, which correlates with the enhanced efficiency of the oxidative ring‐opening reactions and with the limited photochromism of the thiophene‐functionalized derivative.

One-electron oxidation of N-heterocyclic carbenes (NHCs) has been carried out using oxidising agents such as tetracyanoethylene (TCNE) and ferrocenium [Cp(2)Fe](+); the formation of carbene radical cations is postulated.