| SM ISO690:2012|
ROTARU, Mihaela; COCU, Maria; DRAGANCEA, Diana; BULHAK, Ion; BOUROSH, Paulina. Synthesis and crystal structure of new organic ligand based on s-methylisolthiosemicarbazide. In: Ecological and environmental chemistry 2017The 6th International Conference. 2-3 martie 2017, Chișinău. Chisinau, Republic of Moldova: Academy of Sciences of Moldova, 2017, p. 188.
|Ecological and environmental chemistry 2017 2017|
Conferința "Ecological and environmental chemistry 2017" |
Chișinău, Moldova, 2-3 martie 2017
The new organic ligand, S-methylisolthiosemicarbazide of o-vanillin has been obtained by interaction of o-vanillin and S-methylisothiosemicarbazide (in molar ratio 1:1) in methanol. The compound is soluble in chloroform, dimethylformamide, less soluble in ethanol and methanol and insoluble in water. It has been characterized by IR spectroscopy and X-ray diffraction method. In the IR spectrum of potential coordinating agent is observed an intensification of the band at 1648 cm-1 assigned to ν(C=N), which is caused by condensation of o-vanillin and methylated thiosemicarbazide with formation of Schiff base. The characteristic bands of carbonyl and amino components also occur in condensation product. Thus, the bands at 3398 and 3311cm-1 are assigned to as and s (NH2), respectively and 1602cm-1 band to δ (NH2). A medium intensity broad band at 3113cm-1 is assigned to (OH) oscillations of associated group. Methyl groups are characterized by absorption bands in the 30002800cm-1 region (CH3) and 1460 and 1380cm-1 δs and δas (CH3) respectively. As proof of the presence of carbonyl component (o-vanillin) are the most intense bands in the spectrum at 1239cm-1 assigned to (= CO-CH3) and the medium intensity band at 776cm-1 attributed to the presence of three neighboring hydrogen atoms in benzene ring and which demonstrate the type of substitution (1,2,3-) in it. Compound crystallizes in the monoclinic space group P21/n. The conformation of a planar molecule is stabilized by bifurcate intramolecular hydrogen bond O1–H···N1/S1, and thiosemicarbazide fragment adopts cis configuration (isomer Z) (Fig.). Bond distances in thiosemicarbazide fragment (N2–C8 1.303(3) Å, N3–C8 1.339(3) Å) indicate the localization of double and single bonds. Two NHN intermolecular H-bonds form R2 2 (8) synton and join the molecules into centrosymmetrical dimmer. Such dimmers are linked in the crystal by NHO intermolecular Hbonds.