Ionic liquid mediated synthesis and x-ray crystal structure of trans-difluorotetrakis- (1-methylimidazole)iron(III) tetrafluoroborate

Sonochemical Synthesis and Characterization of Ni(C4H6N2)6(PF6)2, Fe(C4H6N2)6(BF4)2, and Ni(C4H6N2)6(BF4)2 in 1‐Butyl‐3‐methylimidazole with Hexafluorophosphate and Tetrafluoroborate

“…[20] The M-N vibrations are observed in the Raman spectra below 300 cm -1 and their locations agree with the literature values. [18,19] The IR and Raman active vibrations due to BF 4 -and PF 6 -anions are present in the spectra and also match the literature values. [21,22] Smaller shifts are observed for these bands, as compared with the literature values.…”

“…The TGA curve reveals that the anions affect the stability of the complexes. [26,27] The weight loss measured at a temperature of 250°C, determined from the curve in Figure 10 (a), is 6.74 % (0.28 mg) for A, 2.00 % (0.11 mg) for B, 5.38 % (0.23 mg) for C and 27.25 % (1.01 mg) for D. The TGA curve shows that the BF 4 -anion complexes are more stable than the PF 6 -anion complexes for both iron and nickel. The thermal stability of the ionic [28] liquids employed in our reactions, (BMI + )(PF 6 -) and (BMI + )(BF 4 -), were also studied using TGA between 25 and 1000°C at a flow rate of 3°C min -1 under N 2 .…”

“…The precursors in all these cases are the corresponding carbonyl complexes [Fe(CO) 5 and Ni(CO) 4 ], which are not soluble in (BMI + )(PF 6 -) and (BMI + )(BF 4 -) ionic liquids. It is well known that pentacarbonyliron and tetracarbonylnickel yield amorphous iron and amorphous nickel when sonicated in decalin (or any other nonvolatile organic solvent) under argon.…”

“…It is well known that pentacarbonyliron and tetracarbonylnickel yield amorphous iron and amorphous nickel when sonicated in decalin (or any other nonvolatile organic solvent) under argon. [7a,7b] On the other hand, the decomposition of Fe(CO) 5 and Ni(CO) 4 in decalin under oxygen yields amorphous metal oxides. [8] The sonochemical decomposition of these carbonyl complexes in (BMI + )(PF 6 -) and (BMI + )(BF 4 -) form crystalline products.…”

Ionic Liquids, 3. Synthesis and Utilisation of Protic Imidazolium Salts in Homogeneous Catalysis

“…In addition to the liquid crystalline 1-alkylimidazolium salts already mentioned, [6] 1-methylimidazolium tetrafluoroborate has been prepared by reacting aqueous tetrafluoroboric acid in ethanol or water with 1-methylimidazole. [8] The recent publication of Ohno and Yoshiwaza on ion conductive characteristics of ILs prepared by neutralisation of 1-alkylimidazoles [9] prompted us to report here on the synergic effect between protonated alkylimidazoles and palladium, rhodium or ruthenium catalysts observed in, respectively, methyl acrylate dimerisation (Pd, Rh) or RCM of N,N-diallyltosylamide (Ru), reactions where the presence of proton is essential for good performances. 4 , OTf, OTs) are free of water as evidenced by the lack of OH stretching absorbances in the 3500 ± 3800 cm À1 region of the IR spectra.…”