1,3-Dimethyl imidazolium iodide

AuBerdem ist die Reduktion von 1,3-Dialkyl-imidazolium-Salzen unter relativ milden Bedin-gungen moglich. So wird z. B. l,3-Dimethyl-4-phenyl-imidazolium-iodid durch Natriumbor-anat in 77% Ausbeute zu I J-Dimethyl-4-phenyl-imidazolidin reduziert1241. 

A related chiral imidazolium salt, l,3-bis[(R)-l-(A)-2-(diphenylphosphinoferrocenyl)ethyl]-imidazolium iodide, 46, has also been prepared in three steps from (R)-A, A -dimethyl-l-ferrocenylethylamine. ... 

Kutuniva J, Oilun-Kaniemi R, Laitinen RS, Asikkala J, Karkkainen J, Lajunen MK (2007) Synthesis and structural characterization of l-butyl-2,3-dimethyl-imidazolium bromide and iodide. Z Naturforsch 62b 868-870... 

Note Reaction of the dimethyl palladium(U) carbene complex with excess methyl iodide leads to decomposition of the compound by reductive elimination of an imidazolium salt that remains pendant on the phosphane anchor [283]. 

The decomposition of the dimethyl palladium(II) carbene complex with excess methyl iodide is a stepwise process. Although the authors [282] propose oxidative addition of methyl iodide on the palladium centre forming an octahedral palladium(IV) complex, it seems much more likely, with respect to the rarity of palladium(IV) compounds [284,285], that the first step is reductive elimination of an imidazolium salt, a decomposition pathway found to be fairly common after the initial publication of McGuinness et al. [283], Oxidative addition of methyl iodide followed by reductive elimination of ethane would account for the accumulation of iodide ligands on the palladium centre and a Pd(0)/Pd(II) redox couple. However, in the last step, a six coordinate Pd(IV) centre still seems to be necessary (see Figure 3.91). 

Imidazolium 2-Cyclopropyl-l,3-dimethyl-4,5-dihydro- -iodid E15/2,2054 (4,5-H2 — imidazol + R-I)... 

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