title: Structural, spectroscopic and theoretical studies of dimethylphenyl betaine complex with two molecules of 2,6-dichloro-4-nitro-phenol.
abstract: The 1:2 complex (1) of dimethylphenyl betaine (DMPB) with two molecules of 2,6-dichloro-4-nitro-phenol (DCNP) was prepared and characterized by X-ray diffraction, B3LYP/6-311++G(d,p) and B3LYP-D3/6-311++G(d,p)calculations, FTIR and NMR spectroscopies. The crystal is monoclinic, space group P21/c with Z=4. The protons at the oxygen atoms of phenols are bonded to each oxygen atoms of the DMPB carboxylate group by two nonequivalent H-bonds with the OH⋯O distances of 2.473(5) and 2.688(4)Å. Both H-bonds in the optimized structures 2 (in vacuum), 3 (in DMSO solution) and dispersion-correlated functional (D3) 4 (in vacuum) are comparable and are slightly shorter than O(6)H(O6)⋯O(2) in the crystal. The FTIR spectrum of 1 shows a broad absorption in the 3400-2000cm(-1) region corresponding to a longer hydrogen bond and a broad absorption in the 1800-500cm(-1) region caused by the shorter H-bond. The relations between the experimental (13)C and (1)H chemical shifts (δexp) of the investigated compound 1 in DMSO solution and GIAO/B3LYP/6-311++G(d,p) magnetic isotropic shielding constants (σcalc) obtained by using the screening solvation model (COSMO) for 3 are linear and reproduce well the experimental chemical shifts described by the equation: δexp=a+b σcalc.
authors.affiliation: Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60780 Poznań, Poland. Electronic address: szafran@amu.edu.pl.
authors.forename: Mirosław
authors.initials: M
authors.lastname: Szafran
authors.affiliation: Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60780 Poznań, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Komasa
authors.affiliation: Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60780 Poznań, Poland.
authors.forename: Kinga
authors.initials: K
authors.lastname: Ostrowska
authors.affiliation: Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60780 Poznań, Poland.
authors.forename: Andrzej
authors.initials: A
authors.lastname: Katrusiak
authors.affiliation: Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60780 Poznań, Poland.
authors.forename: Zofia
authors.initials: Z
authors.lastname: Dega-Szafran
keywords: 2,6-Dichloro-4-nitro-phenol; B3LYP calculations; Dimethylphenyl betaine; FTIR and NMR spectra; Hydrogen bonds; X-ray diffraction