Structural and vibrational study of 3- or 5-methyl substituted 2-N-ethylamino-4-nitropyridine N-oxides
Jadwiga Lorenc , Jerzy Hanuza , J. Janczak
AbstractX-ray crystal structures of two isomers C8H11N3O3, i.e. 2-N-ethylamino-5-methyl-4-nitropyridine N-oxide (EN5MPO) and 2-N-ethylamino-3-methyl-4-nitropyridine N-oxide (EN3MPO) have been determined. The different substitutions of the single bondCH3 groups lead to change of the unit-cell structure, molecular and intermolecular arrangement. Both structures are monoclinic, space group P21/c and P21/n with a parallel and antiparallel orientation along the a-axis, respectively. In each of the two subunits, the methyl carbons and N-atoms of the nitro group are almost coplanar with the pyridine ring, but the N-oxide bonds are inclined from this plane. The crystal structures are stabilized by a set of the weak inter- and intramolecular hydrogen bonds of the Nsingle bondH⋯O type. The structures of both isomers have been confirmed by the results of IR and Raman spectra measurements, quantum chemical calculations and potential energy distribution (PED). The role of methyl group introduced in 3 or 5 position of 2-N-ethylamino-4-nitropyridine N-oxide has been analysed.
|Journal series||Vibrational Spectroscopy, ISSN 0924-2031, (A 25 pkt)|
|Keywords in English||2-N-ethylamino-3-methyl-4-nitropyridine N-oxide, 2-N-ethylamino-5-methyl-4-nitropyridine N-oxide, Crystal structure, Hydrogen bonds, Vibrational properties, DFT calculations|
|Publication indicators||: 2014 = 1.244; : 2012 = 1.747 (2) - 2012=1.978 (5)|
|Citation count*||6 (2016-07-26)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.