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Rita H De Rossi - One of the best experts on this subject based on the ideXlab platform.
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one pot synthesis of 3h 1 2 dithiole 3 thione derivatives from dithiolmalonic esters
Tetrahedron Letters, 2002Co-Authors: Mario L Aimar, Jeronimo Kreiker, Rita H De RossiAbstract:Abstract The reaction of dithiolmalonic esters with P 2 S 5 /S 8 in boiling xylene and with 2-Mercaptobenzothiazole/ZnO as catalyst produces 5-R (R=alkyl or aryl) thio-3 H -1,2-dithiole-3-thiones as the major identifiable product. The use of Lawesson's reagent as sulfurizing agent gives even better yields. For instance with R=phenyl the yield rises from 44 to 82%.
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one pot synthesis of 5 alkylthio 3h 1 2 dithiole 3 thiones advantages and scopes
Synthesis, 2000Co-Authors: Mario L Aimar, Rita H De RossiAbstract:The reaction of dialkyl malonate esters with P 2S5/S8 in boiling xylene in the presence of 2-Mercaptobenzothiazole/ZnO as catalyst produces 5-alkylthio-3 H-1,2-dithiole-3-thiones as major identifiable product. Moderate yields were obtained with malonate esters of primary alcohols. The reaction fails with malonate esters of secondary alcohols. Regarding the substituent in position two, di- alkyl malonates with groups such as CH3, Ph, CH2Ph, OCH3 and Cl afford the corresponding 4-substituted derivatives whereas with Br and NO2 do not give the expected products. Some mechanistic evi- dences are described.
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one pot synthesis of 5 alkylthio 3h 1 2 dithiole 3 thiones
Tetrahedron Letters, 1996Co-Authors: Mario L Aimar, Rita H De RossiAbstract:Abstract Dialkyl malonate esters reacted with P 2 S 5 S 8 in boiling xylene and with 2-Mercaptobenzothiazole ZnO as catalyst to yield 5-alkylthio-3H-1,2-dithiole-3-thiones as major products.
Mario L Aimar - One of the best experts on this subject based on the ideXlab platform.
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one pot synthesis of 3h 1 2 dithiole 3 thione derivatives from dithiolmalonic esters
Tetrahedron Letters, 2002Co-Authors: Mario L Aimar, Jeronimo Kreiker, Rita H De RossiAbstract:Abstract The reaction of dithiolmalonic esters with P 2 S 5 /S 8 in boiling xylene and with 2-Mercaptobenzothiazole/ZnO as catalyst produces 5-R (R=alkyl or aryl) thio-3 H -1,2-dithiole-3-thiones as the major identifiable product. The use of Lawesson's reagent as sulfurizing agent gives even better yields. For instance with R=phenyl the yield rises from 44 to 82%.
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one pot synthesis of 5 alkylthio 3h 1 2 dithiole 3 thiones advantages and scopes
Synthesis, 2000Co-Authors: Mario L Aimar, Rita H De RossiAbstract:The reaction of dialkyl malonate esters with P 2S5/S8 in boiling xylene in the presence of 2-Mercaptobenzothiazole/ZnO as catalyst produces 5-alkylthio-3 H-1,2-dithiole-3-thiones as major identifiable product. Moderate yields were obtained with malonate esters of primary alcohols. The reaction fails with malonate esters of secondary alcohols. Regarding the substituent in position two, di- alkyl malonates with groups such as CH3, Ph, CH2Ph, OCH3 and Cl afford the corresponding 4-substituted derivatives whereas with Br and NO2 do not give the expected products. Some mechanistic evi- dences are described.
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one pot synthesis of 5 alkylthio 3h 1 2 dithiole 3 thiones
Tetrahedron Letters, 1996Co-Authors: Mario L Aimar, Rita H De RossiAbstract:Abstract Dialkyl malonate esters reacted with P 2 S 5 S 8 in boiling xylene and with 2-Mercaptobenzothiazole ZnO as catalyst to yield 5-alkylthio-3H-1,2-dithiole-3-thiones as major products.
şenol Kartal - One of the best experts on this subject based on the ideXlab platform.
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separation preconcentration of trace pb ii and cd ii with 2 Mercaptobenzothiazole impregnated amberlite xad 1180 resin and their determination by flame atomic absorption spectrometry
Arabian Journal of Chemistry, 2017Co-Authors: şerife Tokalioglu, Aysel Papak, şenol KartalAbstract:Abstract A new chelating resin, 2-Mercaptobenzothiazole loaded Amberlite XAD-1180 was prepared and used for separation and preconcentration of Cd(II) and Pb(II) ions prior to their determinations by flame atomic absorption spectrometry. The optimum pH for simultaneous retention of the elements and the best elution means for their simultaneous elution were 9.5 and 2 mol L −1 HNO 3 , respectively. The detection limits for Cd(II) and Pb(II) were 0.35 and 5.0 μg L −1 , respectively. The accuracy of the method was confirmed both by analyzing the certified reference material (RM 8704 Buffalo river sediment) and performing recovery studies.
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Separation/preconcentration of trace Pb(II) and Cd(II) with 2-Mercaptobenzothiazole impregnated Amberlite XAD-1180 resin and their determination by flame atomic absorption spectrometry
Elsevier, 2017Co-Authors: şerife Tokalioglu, Aysel Papak, şenol KartalAbstract:A new chelating resin, 2-Mercaptobenzothiazole loaded Amberlite XAD-1180 was prepared and used for separation and preconcentration of Cd(II) and Pb(II) ions prior to their determinations by flame atomic absorption spectrometry. The optimum pH for simultaneous retention of the elements and the best elution means for their simultaneous elution were 9.5 and 2 mol L−1 HNO3, respectively. The detection limits for Cd(II) and Pb(II) were 0.35 and 5.0 μg L−1, respectively. The accuracy of the method was confırmed both by analyzing the certified reference material (RM 8704 Buffalo river sediment) and performing recovery studies
Ian S Butler - One of the best experts on this subject based on the ideXlab platform.
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synthesis structural characterization and biological studies of six and five coordinate organotin iv complexes with the thioamides 2 Mercaptobenzothiazole 5 chloro 2 Mercaptobenzothiazole and 2 mercaptobenzoxazole
Inorganic Chemistry, 2007Co-Authors: Marianna N Xanthopoulou, Nick Hadjiliadis, Stavroula Skoulika, Thomas Bakas, S K Hadjikakou, Maciej Kubicki, Martin Baril, Ian S ButlerAbstract:Organotin(IV) complexes with the formulas [(C6H5)3Sn(mbzt)] (1), [(C6H5)3Sn(cmbzt)] (3), and [(C6H5)2Sn(cmbzt)2] (4) (Hmbzt = 2-Mercaptobenzothiazole and Hcmbzt = 5-chloro-2-Mercaptobenzothiazole) have been synthesized and characterized by elemental analysis; FT-IR, Raman, 1H, 13C, and 119Sn NMR, and Mossbauer spectroscopic techniques; and X-ray crystallography at various temperatures. The crystal structures of complexes 1, 3, and 4 were determined by X-ray diffraction at room temperature [295(1) or 293(2) K]. The complexes [(C6H5)3Sn(mbzo)] (2) and [(n-C4H9)2Sn(cmbzt)2] (5) (Hmbzo = 2-mercaptobenzoxazole) were synthesized by new improved methods, and their structures were determined at low temperature [100(1) K] and compared to those solved at room temperature. Comparison with {(CH3)2Sn(cmbzt)2]} (6), already reported, was also attempted. The influence of temperature on the geometry of the complexes is discussed. In the cases of complexes 1-3, three carbon atoms from phenyl groups and one sulfur atom and one nitrogen atom from thione ligands form a tetrahedrally distorted trigonal-bipyramidal geometry around the five-coordinate tin(IV) ion. In complexes 4-6, two carbon atoms from aryl groups and two sulfur atoms and two nitrogen atoms from thione ligands form a distorted tetrahedral geometry, tending toward octahedral, around the six-coordinate tin(IV) ions, with trans-C2, cis-N2, and cis-S2 configurations. Although the C-Sn and S-Sn bond distances are found to be constant in compounds 1-6, their N-Sn bond lengths vary significantly (from 2.635 to 3.078 A), with the longer distances found in the cases of five-coordinate complexes 1-3.
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synthesis and characterization of ptu i2 ptu 6 n propyl 2 thiouracil and cmbzt i2 cmbzt 5 chloro 2 Mercaptobenzothiazole and possible implications for the mechanism of action of anti thyroid drugs
European Journal of Inorganic Chemistry, 2003Co-Authors: Constantinos D Antoniadis, Nick Hadjiliadis, S K Hadjikakou, Maciej Kubicki, Ghada J Corban, Stephanie D Warner, Ian S ButlerAbstract:Direct reaction of 6-n-propyl-2-thiouracil (PTU), a widely used anti-thyroid drug against hyperthyroidism (Graves’ disease), or 5-chloro-2-Mercaptobenzothiazole (CMBZTH) with iodine in a molar ratio of 1:1 resulted in the formation of the charge-transfer (CT) complexes [(PTU)I2] (1) or [(CMBZT)I2] (2). All reactions were carried out in dichloromethane and water solutions. Compounds 1 and 2 were characterized by elemental analyses, FT-Raman, FT-IR, UV/Vis and 1H NMR spectroscopy. The crystal structures of both complexes were determined by X-ray diffraction at 120(1) K (1) and 293(2) K (2). The charge-transfer nature of the bonds in the adducts 1 and 2 was verified by the lengthening of the I−I bond lengths as compared to the S−I bond lengths and by the characteristic CT bands observed in the UV spectra of the complexes. Compound 1 [(C7H10N2OS)I2] [monoclinic with space group P21/c and a = 9.8501(7), b = 10.3101(7), c = 12.0287(8) A, β = 99.707(6)°, Z = 4] consists of a propylthiouracil ligand bonded with an iodine atom through sulfur. Extended intermolecular N−H···O contacts link the molecules forming a supramolecular assembly. Compound 2 {(C7H4ClNS2)I2} [orthorhombic, space group P212121, a = 4.1650(10), b = 9.691(2), c = 28.471(6) A, Z = 4] consists of a 5-chloro-2-Mercaptobenzothiazole ligand bonded with an iodine atom through sulfur. An extended intermolecular linkage via I···H−N bonds leads to the formation of an extended structure. Attempts to draw conclusions on the behavior of a thioamide — when used as an anti-thyroidal drug — towards iodine have been made. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
şerife Tokalioglu - One of the best experts on this subject based on the ideXlab platform.
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separation preconcentration of trace pb ii and cd ii with 2 Mercaptobenzothiazole impregnated amberlite xad 1180 resin and their determination by flame atomic absorption spectrometry
Arabian Journal of Chemistry, 2017Co-Authors: şerife Tokalioglu, Aysel Papak, şenol KartalAbstract:Abstract A new chelating resin, 2-Mercaptobenzothiazole loaded Amberlite XAD-1180 was prepared and used for separation and preconcentration of Cd(II) and Pb(II) ions prior to their determinations by flame atomic absorption spectrometry. The optimum pH for simultaneous retention of the elements and the best elution means for their simultaneous elution were 9.5 and 2 mol L −1 HNO 3 , respectively. The detection limits for Cd(II) and Pb(II) were 0.35 and 5.0 μg L −1 , respectively. The accuracy of the method was confirmed both by analyzing the certified reference material (RM 8704 Buffalo river sediment) and performing recovery studies.
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Separation/preconcentration of trace Pb(II) and Cd(II) with 2-Mercaptobenzothiazole impregnated Amberlite XAD-1180 resin and their determination by flame atomic absorption spectrometry
Elsevier, 2017Co-Authors: şerife Tokalioglu, Aysel Papak, şenol KartalAbstract:A new chelating resin, 2-Mercaptobenzothiazole loaded Amberlite XAD-1180 was prepared and used for separation and preconcentration of Cd(II) and Pb(II) ions prior to their determinations by flame atomic absorption spectrometry. The optimum pH for simultaneous retention of the elements and the best elution means for their simultaneous elution were 9.5 and 2 mol L−1 HNO3, respectively. The detection limits for Cd(II) and Pb(II) were 0.35 and 5.0 μg L−1, respectively. The accuracy of the method was confırmed both by analyzing the certified reference material (RM 8704 Buffalo river sediment) and performing recovery studies