کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1412027 1501926 2006 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
X-ray, NMR and DFT studies of the complex of 1,4-dimethylpiperazine mono-betaine with p-hydroxybenzoic acid
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آلی
پیش نمایش صفحه اول مقاله
X-ray, NMR and DFT studies of the complex of 1,4-dimethylpiperazine mono-betaine with p-hydroxybenzoic acid
چکیده انگلیسی

Crystal structure of the 1:1 complex of 1,4-dimethylpiperazine mono-betaine (MBPZ) with p  -hydroxybenzoic acid (HBA) has been determined by X-ray diffraction. The acid molecule is involved in hydrogen bonds with two betaine molecules forming infinite zigzag chains along the [1¯-01] direction, which interact with the other ones only by van der Waals contacts. In this structure, two symmetry-independent hydrogen bonds are formed: the shorter is the O–H⋯O bond of 2.573(2) Å between the hydroxyl group of the acid and the carboxylate group of betaine, and the longer one is the OH⋯N bond of 2.736(3) Å between the carboxylic group and the N(4) atom of piperazine. The piperazine ring has a chair conformation with the N(4)-methyl and N+(1)–CH2COO− groups in the equatorial positions, while the N+(1)-methyl group is in the axial position. The optimized geometry of the complex investigated in the B3LYP/6–31G(d,p) approach is consistent with that in the crystal structure. The 1H and 13C NMR spectra have been analyzed to elucidate the complex structure in the solution.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular Structure - Volume 785, Issues 1–3, 6 March 2006, Pages 160–166
نویسندگان
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