In 2022,Gougoula, Eva; Cummings, Charlotte N.; Medcraft, Chris; Heitkaemper, Juliane; Walker, Nicholas R. published an article in Physical Chemistry Chemical Physics. The title of the article was 《Microwave spectra, molecular geometries, and internal rotation of CH3 in N-methylimidazole···H2O and 2-methylimidazole···H2O complexes》.Safety of 1-Methyl-1H-imidazole The author mentioned the following in the article:
Broadband microwave spectra have been recorded between 7.0 and 18.5 GHz for N-methylimidazole···H2O and 2-methylimidazole···H2O complexes. Each complex was generated by co-expansion of low concentrations of methylimidazole and H2O in argon buffer gas. The rotational spectra of five isotopologues of each complex have been assigned and analyzed to determine rotational constants (A0, B0, C0), centrifugal distortion constants (DJ, DJK) and parameters that describe the internal rotation of the CH3 group. The results allow the determination of parameters in the (r0) mol. geometry of each complex. H2O is the hydrogen bond donor and the pyridinic nitrogen of imidazole is the hydrogen bond acceptor in each case. The ∠(O-Hb···N3) angles are 177(5)° and 166.3(28)° for N-methylimidazole···H2O and 2-methylimidazole···H2O resp. These results are consistent with the presence of a weak electrostatic interaction between the oxygen atom of H2O and the hydrogen atom (or CH3 group) attached to the C2 carbon atom of imidazole, and with the results of d. functional theory calculations The (V3) barrier to internal rotation of the CH3 group within N-methylimidazole···H2O is essentially unchanged from the value of this parameter for the N-methylimidazole monomer. The same parameter is significantly higher for the 2-methylimidazole···H2O complex than for the 2-methylimidazole monomer as a consequence of the weak electrostatic interaction between the O atom and the CH3 group of 2-methylimidazole. The experimental part of the paper was very detailed, including the reaction process of 1-Methyl-1H-imidazole(cas: 616-47-7Safety of 1-Methyl-1H-imidazole)
1-Methyl-1H-imidazole(cas: 616-47-7) is used as a precursor for the synthesis of pyrrole-imidazole polyamides, ionic liquids such as 1-butyl-3-methylimidazolium hexafluorophosphate.Safety of 1-Methyl-1H-imidazole
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem