chemicallytechFine Chemical TechnologiesТонкие химические технологии2410-65932686-7575MIREA – Russian Technological University (RTU MIREA).10.32362/2410-6593-2017-12-2-34-41chemicallytech-80Research ArticleCHEMISTRY AND TECHNOLOGY OF INORGANIC MATERIALSХИМИЯ И ТЕХНОЛОГИЯ НЕОРГАНИЧЕСКИХ МАТЕРИАЛОВTHERMAL DECOMPOSITION OF UROTROPINE COMPLEXES WITH NICKEL AND COBALT CHLORIDESИССЛЕДОВАНИЕ ТЕРМИЧЕСКОГО РАЗЛОЖЕНИЯ КОМПЛЕКСНЫХ СОЕДИНЕНИЙ ХЛОРИДОВ НИКЕЛЯ И КОБАЛЬТА С УРОТРОПИНОМГолубевД. В.GolubevD. V.

кандидат химических наук, главный специалист Центра коллективного пользования

119571, Россия, Москва, пр-т Вернадского, д. 86

Moscow, 119571 Russia

noemail@neicon.ruСавинкинаЕ. В.SavinkinaE. V.

доктор химических наук, профессор кафедры неорганической химии им. А.Н. Реформатского

119571, Россия, Москва, пр-т Вернадского, д. 86

Moscow, 119571 Russia

e.savinkina@mail.ruАль-ХазраджиА. С.Al-KhazrajiA. ..

студент Института тонких химических технологий

119571, Россия, Москва, пр-т Вернадского, д. 86

Moscow, 119571 Russia

noemail@neicon.ruДавыдоваМ. Н.DavydovaM. N.

кандидат химических наук, доцент кафедры неорганической химии им. А.Н. Реформатского

119571, Россия, Москва, пр-т Вернадского, д. 86

Moscow, 119571 Russia

noemail@neicon.ruМосковский технологический университет (Институт тонких химических технологий)РоссияMoscow Technological University (Institute of Fine Chemical Technologies)Russian Federation2017280420171223441Copyright © Golubev D.V., Savinkina E.V., Al-Khazraji A..., Davydova M.N., 20172017Голубев Д.В., Савинкина Е.В., Аль-Хазраджи А.С., Давыдова М.Н.Golubev D.V., Savinkina E.V., Al-Khazraji A..., Davydova M.N.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.finechem-mirea.ru/jour/article/view/80

Complex compounds NiCl2·2HMTA·10H2O (1), CoCl2·2HMTA·10H2O (2), CoCl2·HMTA·4.5H2O (3) were prepared by the reaction of nickel(II) and cobalt(II) chlorides with urotropine (HMTA). Compounds 1 and 2 are isostructural, their structure corresponds to the earlier studied crystal structure [Ni(H2O)6]Cl2·4H2O·2HMTA. Thermal destruction of the complex compounds 1-3 was studied by TGA and high-temperature IR-spectroscopy. The TGA curve for compound 1 shows stepwise mass loss caused by two-stage loss of all water molecules (up to 170°C) and one urotropine molecule (up to 270°C) followed by decomposition of NiCl2·HMTA. The X-ray diffraction pattern of the resulting solid shows no reflections typical for the metal and its simplest nitrogen-, carbon- and chlorine-containing compounds. Thermal decomposition of сompounds 2 and 3 proceed similarly, but water is removed in one stage. IR spectra, which were recorded at high temperature (up to 220-230°C) show gradual decrease of intensity of the bands assigned to vibrations of water molecules. The bands of the methylene groups of urotropine do not change on heating. However, the bands of the C-N vibrations shift from ~1050 and ~1008 cm-1 in the spectra of urotropine and [M(H2O)6](HMTA)2Cl2·4H2O to 1015-1019 and 984-995 cm-1, respectively, indicating coordination of urotropine molecules instead of the removed water molecules. The long-wave IR spectra for NiCl2·6H2O and compound 1 at ambient temperature show bands of Ni-O stretching vibrations and O-Ni-O bending vibrations. After heating 1 at 115° C, bands of Ni-N and Ni-Cl appear, which indicates the coordination of urotropine molecules and chloride ions after the removal of outer-sphere and inner-sphere water molecules.

Взаимодействием хлоридов никеля(II) и кобальта(II) с уротропином (HMTA) получены комплексные соединения состава NiCl2·2HMTA·10H2O (1), CoCl2·2HMTA·10H2O (2), CoCl2·HMTA·4.5H2O (3). Показано, что соединения 1 и 2 изоструктурны и отвечают ранее описанному [Ni(H2O)6]Cl2·4H2O·2HMTA. На кривой ТГА соединения 1 наблюдается ступенчатое уменьшение массы, связанное с двухстадийной потерей всех молекул воды (до 170°С) и одной молекулы уротропина (до 270°С), далее происходит разложение фрагмента NiCl2·HMTA. На дифрактограмме твердого остатка, полученного после нагревания образца до 800°С, не удалось обнаружить отражений, характерных для металла и его простейших азот-, углерод- и хлорсодержащих соединений. Термическое разложение соединений 2 и 3 протекает аналогично, но вода удаляется в одну стадию. В ИК-спектрах, измеренных при повышенных температурах, вплоть до 220-230°С, имеет место постепенное уменьшение интенсивности полос, отвечающих колебаниям молекул воды. Полосы, отнесенные к колебаниям метиленовых групп уротропина, остаются в указанном интервале температур практически без изменений. В то же время уже при нагревании выше 130°С отмечается сдвиг полос, обусловленных валентными колебаниями связей C-N, от ~1050 и ~1008 см-1 в спектрах свободного уротропина и [M(H2O)6](HMTA)2Cl2·4H2O к 1015-1019 и 984-995 см-1, соответственно, что свидетельствует о координации атомами никеля и кобальта молекул уротропина вместо удаленных молекул воды. В длинноволновых ИК-спектрах для NiCl2·6H2O и соединения 1 при комнатной температуре наблюдаются полосы валентных колебаний Ni-O и деформационных колебаний O-Ni-O. После нагревания 1 при 115°С в спектре появляются полосы колебаний Ni-N и Ni-Cl, что свидетельствует о координации атомом никеля молекул уротропина и хлорид-ионов после удаления внешнесферных и внутрисферных молекул воды.

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The authors declare that there are no conflicts of interest present.