Pub Date : 2007-08-22DOI: 10.1080/00945718408058260
A. Syamal, D. Kumar
Abstract New zirconium(IV) heterochelates of the type Zr(O)2 (BB) (AAA) (where AAA = Schiff base derived from benzoylhydrazide and salicylaldehyde, BB = orthophenanthroline, 2, 2′ -dipyridyl, ethylenediamine, tri-methylenediamine, tetramethylenediamine or orthophenylenediamine) have been synthesized and characterized on the basis of elemental analysis, molar conductance, molecular weight, IR and magnetic susceptibility measurements. AAA and BB behave as tridentate and bidentate ligands, respectively. The hetero-chelates are monomers, non-electrolytes, diamagnetic and seven-coordinate.
{"title":"Zirconium(IV) Heterochelates","authors":"A. Syamal, D. Kumar","doi":"10.1080/00945718408058260","DOIUrl":"https://doi.org/10.1080/00945718408058260","url":null,"abstract":"Abstract New zirconium(IV) heterochelates of the type Zr(O)2 (BB) (AAA) (where AAA = Schiff base derived from benzoylhydrazide and salicylaldehyde, BB = orthophenanthroline, 2, 2′ -dipyridyl, ethylenediamine, tri-methylenediamine, tetramethylenediamine or orthophenylenediamine) have been synthesized and characterized on the basis of elemental analysis, molar conductance, molecular weight, IR and magnetic susceptibility measurements. AAA and BB behave as tridentate and bidentate ligands, respectively. The hetero-chelates are monomers, non-electrolytes, diamagnetic and seven-coordinate.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2007-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90534749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The o,o′‐dihydroxyazo dye, 1‐(2‐hydroxy‐4‐methylphenylazo)‐2‐naphthol (HMPAN), and its metal complexes (chromium, cobalt, and iron) having the ligand to metal ratio 2:1 have been synthesized, but manganese forms a 1:1 complex. The spectral characterization of HMPAN and its complexes by IR, UV–VIS, 1H and 13C NMR spectroscopic techniques, and elemental analyses are reported.
{"title":"Synthesis and Spectral Characterization of Metal Complexes of 1‐(2‐Hydroxy‐4‐methylphenylazo)‐2‐naphthol","authors":"H. Kocaokutgen, E. Erdem","doi":"10.1081/SIM-200030245","DOIUrl":"https://doi.org/10.1081/SIM-200030245","url":null,"abstract":"Abstract The o,o′‐dihydroxyazo dye, 1‐(2‐hydroxy‐4‐methylphenylazo)‐2‐naphthol (HMPAN), and its metal complexes (chromium, cobalt, and iron) having the ligand to metal ratio 2:1 have been synthesized, but manganese forms a 1:1 complex. The spectral characterization of HMPAN and its complexes by IR, UV–VIS, 1H and 13C NMR spectroscopic techniques, and elemental analyses are reported.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77350548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract A new series of Cu(II) complexes of naphthylideneamino acid Schiff bases (H2naph:aa) as a primary ligand and imidazole or 2‐methylimidazole (B) as a secondary ligand has been synthesized and characterized. The analytical data and physical characterization have proved that the complexes are four‐coordinate with the general formula [Cu(II)(naph:aa)B]. The structure of the complexes is suggested to be square‐planar. The adsorption of the formed complexes on a hanging mercury drop electrode (HMDE) was performed in 0.1 mol dm−3 KCl solution utilizing cyclic voltammetric and chronocoulometric techniques. The results indicate that an adsorption of copper(II) adducts occurs on the mercury electrode and the amount adsorbed expressed as excess surface coverage, Γ, was determined. The values of Γ calculated chronocoulometrically are almost the same as those calculated by cyclic voltammetry.
{"title":"Synthesis, Characterization, and Electrochemical Adsorption Study on Mercury Electrode of New Ternary Cu(II) Complexes of N‐Naphthylideneamino Acids with Imidazoles","authors":"A. Abdel‐Mawgoud, H. M. El‐Sagher, M. K. Rabia","doi":"10.1081/SIM-200030135","DOIUrl":"https://doi.org/10.1081/SIM-200030135","url":null,"abstract":"Abstract A new series of Cu(II) complexes of naphthylideneamino acid Schiff bases (H2naph:aa) as a primary ligand and imidazole or 2‐methylimidazole (B) as a secondary ligand has been synthesized and characterized. The analytical data and physical characterization have proved that the complexes are four‐coordinate with the general formula [Cu(II)(naph:aa)B]. The structure of the complexes is suggested to be square‐planar. The adsorption of the formed complexes on a hanging mercury drop electrode (HMDE) was performed in 0.1 mol dm−3 KCl solution utilizing cyclic voltammetric and chronocoulometric techniques. The results indicate that an adsorption of copper(II) adducts occurs on the mercury electrode and the amount adsorbed expressed as excess surface coverage, Γ, was determined. The values of Γ calculated chronocoulometrically are almost the same as those calculated by cyclic voltammetry.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79386206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The complexes [M(L)(H2O) x ] n [M = Co(II), Ni(II), Cu(II), Zn(II), Cd(II)] and [M2(L)3] n [M = Mn(III), Fe(III)] and [VO(HL)2] with N‐picolinoyl‐N′‐2‐furanthiocarbohydrazide (H2L) have been prepared and characterized by elemental analyses, magnetic susceptibility measurement, electronic, NMR (1H and 13C), IR and FAB mass spectral data. Physico‐chemical studies indicate that the complexes are polymeric in nature. The room temperature ESR spectra of [VO(HL)2] and [Cu(L)] n complexes yield ⟨g⟩ values, characteristic of square‐pyramidal and square‐planar complexes, respectively. The Mössbauer spectra of [Fe2(L)3] n at room temperature and at 78 K suggest the presence of high‐spin (S = 5/2) and low‐spin (S = 1/2) forms of Fe(III) in the same complex at both temperatures. The complexes of OV(IV), Fe(III), Ni(II), and Cd(II) show semiconducting behaviour in the solid state in the temperature range 307–397 K, with a band gap of 0.18–0.44 eV. The other complexes are insulators.
{"title":"Complexes of N‐Picolinoyl‐N′‐2‐furanthiocarbohydrazide with Oxovanadium(IV), Manganese(III), Iron(III), Cobalt(II), Nickel(II), Copper(II), Zinc(II), and Cadmium(II)","authors":"N. Singh, S. K. Kushawaha","doi":"10.1081/SIM-200030207","DOIUrl":"https://doi.org/10.1081/SIM-200030207","url":null,"abstract":"Abstract The complexes [M(L)(H2O) x ] n [M = Co(II), Ni(II), Cu(II), Zn(II), Cd(II)] and [M2(L)3] n [M = Mn(III), Fe(III)] and [VO(HL)2] with N‐picolinoyl‐N′‐2‐furanthiocarbohydrazide (H2L) have been prepared and characterized by elemental analyses, magnetic susceptibility measurement, electronic, NMR (1H and 13C), IR and FAB mass spectral data. Physico‐chemical studies indicate that the complexes are polymeric in nature. The room temperature ESR spectra of [VO(HL)2] and [Cu(L)] n complexes yield ⟨g⟩ values, characteristic of square‐pyramidal and square‐planar complexes, respectively. The Mössbauer spectra of [Fe2(L)3] n at room temperature and at 78 K suggest the presence of high‐spin (S = 5/2) and low‐spin (S = 1/2) forms of Fe(III) in the same complex at both temperatures. The complexes of OV(IV), Fe(III), Ni(II), and Cd(II) show semiconducting behaviour in the solid state in the temperature range 307–397 K, with a band gap of 0.18–0.44 eV. The other complexes are insulators.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84089213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Baranwal, Tarkeshwar Gupta, Deen Dayal Upadhyay
Abstract A series of iron(II,III,III) and cobalt(II) complexes of thiocarboxylic acids of the general formulas [FeIIFe2 IIIO(SOCR)6(L)3] and [Co(SOCR)2(L)2] (R = C2H5 or C(CH3)3 and L = EtOH or py) have been synthesized and characterized by elemental and thermogravimetric analyses, spectral (infrared, electronic, and Mössbauer) studies, molar conductance, magnetic susceptibility, and molecular weight determinations. The electronic spectral data suggested an octahedral environment around the metal ion in both the iron as well as the cobalt complexes. A band around 13,800 cm−1 in the electronic spectra of the iron complexes indicated intervalence‐transfer between Fe(II) and Fe(III) moieties. A bridging mode of coordination could be assigned for the thiocarboxylate anions in the iron complexes and a chelating mode of coordination for the cobalt complexes have been suggested by infrared spectral data along with a new band at 540 cm−1, which may be ascribed owing to νasy(Fe3O) vibrations. Mössbauer studies revealed two resolved quadrupole doublets at 120–315 K confirming the presence of Fe(II) and Fe(III) moities in the iron complexes. Thermoanalytical data indicated the iron complexes were thermally stable up to 135 °C, whereas the cobalt complexes were stable up to 160 °C, above which temperature decomposition started and continued to ∼400 °C at which temperature the formation of metal sulfide and/or oxide was noticed. An attempt has been made to establish the structures based on these studies.
{"title":"Synthesis and Physico‐Chemical Studies on Iron(II,III,III) and Cobalt(II) Thiocarboxylates","authors":"B. Baranwal, Tarkeshwar Gupta, Deen Dayal Upadhyay","doi":"10.1081/SIM-200030186","DOIUrl":"https://doi.org/10.1081/SIM-200030186","url":null,"abstract":"Abstract A series of iron(II,III,III) and cobalt(II) complexes of thiocarboxylic acids of the general formulas [FeIIFe2 IIIO(SOCR)6(L)3] and [Co(SOCR)2(L)2] (R = C2H5 or C(CH3)3 and L = EtOH or py) have been synthesized and characterized by elemental and thermogravimetric analyses, spectral (infrared, electronic, and Mössbauer) studies, molar conductance, magnetic susceptibility, and molecular weight determinations. The electronic spectral data suggested an octahedral environment around the metal ion in both the iron as well as the cobalt complexes. A band around 13,800 cm−1 in the electronic spectra of the iron complexes indicated intervalence‐transfer between Fe(II) and Fe(III) moieties. A bridging mode of coordination could be assigned for the thiocarboxylate anions in the iron complexes and a chelating mode of coordination for the cobalt complexes have been suggested by infrared spectral data along with a new band at 540 cm−1, which may be ascribed owing to νasy(Fe3O) vibrations. Mössbauer studies revealed two resolved quadrupole doublets at 120–315 K confirming the presence of Fe(II) and Fe(III) moities in the iron complexes. Thermoanalytical data indicated the iron complexes were thermally stable up to 135 °C, whereas the cobalt complexes were stable up to 160 °C, above which temperature decomposition started and continued to ∼400 °C at which temperature the formation of metal sulfide and/or oxide was noticed. An attempt has been made to establish the structures based on these studies.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81738042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In this article, 3,3′‐bis(N‐ferrocenylmethylene formylhydrazone)‐2,2′‐bipyridyl and its Cd(II), Hg(II), Cu(II), and Mn(II) complexes have been synthesized and characterized by elemental analyses, IR, 1H NMR spectral, thermal analyses, and molar conductances. In the complexes, 3,3′‐bis(N‐ferrocenylmethylene formylhydrazone)‐2,2′‐bipyridyl coordinates to the transition metal ions using a methylenimine nitrogen, the amide oxygen in the enolic form, the pyridyl nitrogen, the acetate in a symmetrical bidentate manner, and one water molecule, all of which participate in coordination to form a binuclear complex. The ligand and the complexes are insoluble in common organic solvents and slightly soluble in strongly polar solvents such as DMF and DMSO.
{"title":"Synthesis and Characterization of 3,3′‐bis(N‐Ferrocenyl methylene formylhydrazone)‐2,2′‐bipyridyl and its Cd(II), Hg(II), Cu(II), and Mn(II) Complexes","authors":"Benlai Wu, Chengbin Liu, Mingxing Yao, Hong‐yun Zhang, Pei‐kun Chen, Hong-Yan Mao, Xiao‐qing Shen, Shouchang Liu","doi":"10.1081/SIM-200030165","DOIUrl":"https://doi.org/10.1081/SIM-200030165","url":null,"abstract":"Abstract In this article, 3,3′‐bis(N‐ferrocenylmethylene formylhydrazone)‐2,2′‐bipyridyl and its Cd(II), Hg(II), Cu(II), and Mn(II) complexes have been synthesized and characterized by elemental analyses, IR, 1H NMR spectral, thermal analyses, and molar conductances. In the complexes, 3,3′‐bis(N‐ferrocenylmethylene formylhydrazone)‐2,2′‐bipyridyl coordinates to the transition metal ions using a methylenimine nitrogen, the amide oxygen in the enolic form, the pyridyl nitrogen, the acetate in a symmetrical bidentate manner, and one water molecule, all of which participate in coordination to form a binuclear complex. The ligand and the complexes are insoluble in common organic solvents and slightly soluble in strongly polar solvents such as DMF and DMSO.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85855455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Octahedral bis‐hydrazine metal glycolates and chloroacetates, [MX2(N2H4)2] n , where M = Co, Ni, or Zn for X = HOCH2COO and M = Mn, Co, Ni, Zn, or Cd for X = ClCH2COO have been prepared and characterised by chemical analyses, magnetic moments, electronic and infrared spectra, and thermal analyses (TG, DTG, and DTA). Infrared spectra show the presence of bridging bidentate (ν(N–N) = 970 cm−1) hydrazines and monodentate carboxylate ions. The thermal studies indicate that the glycolate complexes decompose at lower temperatures (60–450 °C) than the chloroacetates which decompose in the temperature range 100–600 °C. The x‐ray powder diffraction lines imply that the compounds in each series of complexes are isomorphous with each other. However, there appears to be no similarity in the x‐ray powder diffraction pattern between the two series of complexes.
{"title":"bis‐Hydrazine Metal Glycolates and Chloroacetates: Synthesis, Spectral, and Thermal Studies","authors":"B. Sivasankar, J. Sharmila, L. Ragunath","doi":"10.1081/SIM-200030212","DOIUrl":"https://doi.org/10.1081/SIM-200030212","url":null,"abstract":"Abstract Octahedral bis‐hydrazine metal glycolates and chloroacetates, [MX2(N2H4)2] n , where M = Co, Ni, or Zn for X = HOCH2COO and M = Mn, Co, Ni, Zn, or Cd for X = ClCH2COO have been prepared and characterised by chemical analyses, magnetic moments, electronic and infrared spectra, and thermal analyses (TG, DTG, and DTA). Infrared spectra show the presence of bridging bidentate (ν(N–N) = 970 cm−1) hydrazines and monodentate carboxylate ions. The thermal studies indicate that the glycolate complexes decompose at lower temperatures (60–450 °C) than the chloroacetates which decompose in the temperature range 100–600 °C. The x‐ray powder diffraction lines imply that the compounds in each series of complexes are isomorphous with each other. However, there appears to be no similarity in the x‐ray powder diffraction pattern between the two series of complexes.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88333238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Slaouti, S. Boutamine, Z. Hank, O. Zekri, M. Meklati, O. Vittori
Abstract The interaction of an ethanolic solution of benzaldoxime, C6H5–CH˭NOH (HL), with aqueous solutions of V(V) or V(IV) has been studied. These reactions lead to the formation of a series of compounds: (1) a green decavanadate salt of the formula H4Na2V10O27(OH) · 6H2O; (2) a yellow‐green dimeric coordination complex of the formula V2O3(OH)(L*)2(HL)2 in which L* is the deprotonated species of the oxidized form of benzaldoxime, (C6H5C(H−)NO2); and (3) a green monomeric complex of the formula [VO(H2O)2(L)2] · 2H2O in which L is the deprotonated form of benzaldoxime, (C6H5–CH˭NO−). Elemental analyses, conductometry, infrared spectroscopy, UV‐Visible spectrometry, nuclear magnetic resonance (NMR), electronic paramagnetic resonance (ESR), and mass spectroscopy have been used to elucidate the structures of the resultant compounds. Magnetic measurements, ESR spectroscopy, and UV‐Visible spectrometry have shown the existence of a lower oxidation state of vanadium in some of these compounds. The reduction of V(V) to V(IV) was due to a ligand–metal redox reaction.
{"title":"Synthesis and Characterisation of Some Vanadium(V) and (IV) Compounds with Benzaldoxime","authors":"H. Slaouti, S. Boutamine, Z. Hank, O. Zekri, M. Meklati, O. Vittori","doi":"10.1081/SIM-200030216","DOIUrl":"https://doi.org/10.1081/SIM-200030216","url":null,"abstract":"Abstract The interaction of an ethanolic solution of benzaldoxime, C6H5–CH˭NOH (HL), with aqueous solutions of V(V) or V(IV) has been studied. These reactions lead to the formation of a series of compounds: (1) a green decavanadate salt of the formula H4Na2V10O27(OH) · 6H2O; (2) a yellow‐green dimeric coordination complex of the formula V2O3(OH)(L*)2(HL)2 in which L* is the deprotonated species of the oxidized form of benzaldoxime, (C6H5C(H−)NO2); and (3) a green monomeric complex of the formula [VO(H2O)2(L)2] · 2H2O in which L is the deprotonated form of benzaldoxime, (C6H5–CH˭NO−). Elemental analyses, conductometry, infrared spectroscopy, UV‐Visible spectrometry, nuclear magnetic resonance (NMR), electronic paramagnetic resonance (ESR), and mass spectroscopy have been used to elucidate the structures of the resultant compounds. Magnetic measurements, ESR spectroscopy, and UV‐Visible spectrometry have shown the existence of a lower oxidation state of vanadium in some of these compounds. The reduction of V(V) to V(IV) was due to a ligand–metal redox reaction.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85016414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Yoder, Nathan Fedors, Natalie J. Flora, H. Brown, K. Hamilton, C. D. Schaeffer
Abstract The existence of pure‐phase transition metal hydroxy apatites of zinc, copper, manganese, and cobalt could not be verified by repeated attempts to duplicate the few literature procedures reported for their preparation in aqueous solution. Variations of temperature, time of reactions, pH, and use of decomplexation also did not produce apatitic compounds. In the case of zinc, the product resulting from the addition of zinc nitrate to ammonium dihydrogen phosphate in solutions brought to pH >9 with ammonia appears to be a zinc ammonia complex with phosphate as the counter ion. Extensive drying removed ammonia to produce the phosphate. At pH <8.5 several hydrates of zinc phosphate were formed. With copper, the use of literature procedures and variations thereon resulted in libethenite, Cu2(PO4)OH. The literature procedure for the cobalt(II) apatite using ethylenediamine produced no precipitate; at pH 5, Co3(PO4)2 · H2O was formed in the presence of ethylenediamine. The Mahapatra procedure for the manganese apatite produced a mixture of Mn3(PO4)2 · 3H2O and hureaulite, Mn5(PO4)2[PO3(OH)]2, whereas the Rao method resulted in (NH4)MnPO4 · H2O. On extensive heating all of the products decomposed to the anhydrous phosphate. The instability of the apatites in aqueous solution is attributed to their solubility, supported by an approximate calculation of ΔG dissolution for the zinc apatite. The underlying thermodynamic reason for the solubility appears to be the large negative heat of hydration of the relatively small, polarizable transition metal cations.
{"title":"The Existence of Pure‐Phase Transition Metal Hydroxy Apatites","authors":"C. Yoder, Nathan Fedors, Natalie J. Flora, H. Brown, K. Hamilton, C. D. Schaeffer","doi":"10.1081/SIM-200030243","DOIUrl":"https://doi.org/10.1081/SIM-200030243","url":null,"abstract":"Abstract The existence of pure‐phase transition metal hydroxy apatites of zinc, copper, manganese, and cobalt could not be verified by repeated attempts to duplicate the few literature procedures reported for their preparation in aqueous solution. Variations of temperature, time of reactions, pH, and use of decomplexation also did not produce apatitic compounds. In the case of zinc, the product resulting from the addition of zinc nitrate to ammonium dihydrogen phosphate in solutions brought to pH >9 with ammonia appears to be a zinc ammonia complex with phosphate as the counter ion. Extensive drying removed ammonia to produce the phosphate. At pH <8.5 several hydrates of zinc phosphate were formed. With copper, the use of literature procedures and variations thereon resulted in libethenite, Cu2(PO4)OH. The literature procedure for the cobalt(II) apatite using ethylenediamine produced no precipitate; at pH 5, Co3(PO4)2 · H2O was formed in the presence of ethylenediamine. The Mahapatra procedure for the manganese apatite produced a mixture of Mn3(PO4)2 · 3H2O and hureaulite, Mn5(PO4)2[PO3(OH)]2, whereas the Rao method resulted in (NH4)MnPO4 · H2O. On extensive heating all of the products decomposed to the anhydrous phosphate. The instability of the apatites in aqueous solution is attributed to their solubility, supported by an approximate calculation of ΔG dissolution for the zinc apatite. The underlying thermodynamic reason for the solubility appears to be the large negative heat of hydration of the relatively small, polarizable transition metal cations.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75296111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The complexes of Co(II), Cu(II), Ni(II), Cd(II), Hg(II), Zn(II), UO2(VI), and Th(IV) with benzofuran thiosemicarbazides have been prepared. All complexes have the general formula MLX n , where n = 2 or 4, X = Cl or NO3 and L is the ligand prepared by the reaction of benzofuran‐2‐carboxyhydrazide with p‐methyl, p‐methoxy, or p‐bromophenylisothiocyanate. The complexes were characterized on the basis of elemental analyses, spectral, magnetic moment, and conductance studies. The ligands coordinate to the metal ions through the oxygen of the arbonyl group and the nitrogen of the hydrazine group. We have assigned the probable geometry for all of these complexes based on their physico‐chemical data. All the metal complexes and ligands were screened for their anti‐microbial activity.
{"title":"Synthesis, Spectral Studies, and Biological Activity of Metal Complexes of Benzofuran Thiosemicarbazides","authors":"M. B. Halli, Shashidhar, Z. S. Qureshi","doi":"10.1081/SIM-200030199","DOIUrl":"https://doi.org/10.1081/SIM-200030199","url":null,"abstract":"Abstract The complexes of Co(II), Cu(II), Ni(II), Cd(II), Hg(II), Zn(II), UO2(VI), and Th(IV) with benzofuran thiosemicarbazides have been prepared. All complexes have the general formula MLX n , where n = 2 or 4, X = Cl or NO3 and L is the ligand prepared by the reaction of benzofuran‐2‐carboxyhydrazide with p‐methyl, p‐methoxy, or p‐bromophenylisothiocyanate. The complexes were characterized on the basis of elemental analyses, spectral, magnetic moment, and conductance studies. The ligands coordinate to the metal ions through the oxygen of the arbonyl group and the nitrogen of the hydrazine group. We have assigned the probable geometry for all of these complexes based on their physico‐chemical data. All the metal complexes and ligands were screened for their anti‐microbial activity.","PeriodicalId":22160,"journal":{"name":"Synthesis and Reactivity in Inorganic and Metal-organic Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79586912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：