Calcium and strontium thiobarbiturates with discrete and polymeric structures

Abstract

S), were synthesized and characterized by FT-IR spectroscopy, TG-DSC, and singlecrystal and powder X-ray diffraction analysis. The single-crystal X-ray diffraction data revealed that 1 and 2 are discrete structures, whereas 3 is a polymer. In 1 and 2, Ca 2+ is seven-coordinate and forms a monocapped trigonal prism. In 1, the prisms are pairwise connected with the assistance of two [μ 2 -HTBA-O,O′] − ligands. In 3, Sr 2+ is coordinated by four monodentate HTBA − via S or O donors and four waters, with the formation of a distorted square antiprism. The antiprisms are connected by μ 2 -O,S bridging HTBA − . Hydrogen bonding involving coordinated water and π-π interactions plays an important role in construction of the supramolecular 3-D structures in 1-3. Infrared spectroscopic data supported the structural data. The thermal stability of 1-3 decreases in the order 1 > 2 > 3. Dehydration of 1-3 was a multi-step process, followed by exothermic oxidative degradation of the 2-thiobarbiturate moiety between 290 and 800°C.

Thiobarbiturate and barbiturate salts of pefloxacin drug: Growth, structure, thermal stability and IR-spectra

“…The main bond lengths and valence angles are shown in Table 1S. They coincide with those found earlier for 1 and given in the literature for ions PefH2 + [21][22][23][24] and Htba − [25][26][27][28][29].…”

First outer-sphere 1,3-diethyl-2-thiobarbituric compounds [M(H2O)6](1,3-diethyl-2-thiobarbiturate)2·2H2O (M = Co2+, Ni2+): Crystal structure, spectroscopic and thermal properties

“…Such delocalization was observed in alkali and other metal compounds of 2-thiobarbiturates. [25][26][27][35][36][37][38][39][40][41][42][43][44][45][46][47][48]. Previously, two different conformational states: conformer (A) with large value of torsion angle C8AC7AC9AC10 ($150°) and conformer (B) with a small value of this angle ($0.…”

Structure of Hydrates of Metal Complexes with Barbituric Acids

“…барбитуровой кислоты карбонатом кальция [9]. Кристаллизацией из водного раствора при Нейтрализацией SrCO 3 2-тиобарбитуровой кислотой в воде при 60 ºC получен кристалло-…”

“…личестве только при продолжительном испарении полученного в предыдущем синтезе филь-трата в течение ~30 дней [9]. Реакций между эквимолярными количествами BaCO 3 и H 2 tba в воде при 60 ºС получены При нагревании происходит последовательная дегидратация 11: Стехиометрические соотношения между гидратами 1,3-диэтил-2-тиобарбитурата Mn(II) та-ковы:…”