Muhammad Altaf - Academia.edu (original) (raw)
Papers by Muhammad Altaf
Gold(I) complexes of 2-(diphenylphosphanyl)ethylamine or (2-aminoethyl)diphenylphosphine (AEP), a... more Gold(I) complexes of 2-(diphenylphosphanyl)ethylamine or (2-aminoethyl)diphenylphosphine (AEP), and dithiocaarbamates (R 2 NCS 2) were prepared by the reaction of these ligands with (CH 3) 2 S-AuCl in dichloromethane. The synthesized complexes [Au(AEP)Cl] (1), [Au(AEP) 2 ]Cl (2), and [Au 2 (R 2 NCS 2) 2 ] n (R 2 = di-methyl (3), diethyl (4), and dibenzyl (5)) were characterized by ele
Journal of Chemical Crystallography, 2011
Acta Crystallogr E Struct Rep, 2006
Single-crystal X-ray study T = 173 K Mean (C-C) = 0.003 Å R factor = 0.039 wR factor = 0.086 Data... more Single-crystal X-ray study T = 173 K Mean (C-C) = 0.003 Å R factor = 0.039 wR factor = 0.086 Data-to-parameter ratio = 20.0
Acta Crystallogr E Struct Rep, 2010
Inorganic Reaction Mechanisms, 2006
![Research paper thumbnail of Green chemistry synthesis: 2-amino-3-[(E)-(2-pyridyl)methylideneamino]but-2-enedinitrile monohydrate and 5-cyano-2-(2-pyridyl)-1-(2-pyridylmethyl)-1H-imidazole-4-carboxamide](https://attachments.academia-assets.com/51293626/thumbnails/1.jpg)
](Acta crystallographica. Section C, Crystal structure communications, 2010
The title compounds, C(10)H(9)N(5)O.H(2)O (L1.H(2)O) and C(16)H(12)N(6)O (L2), were synthesized b... more The title compounds, C(10)H(9)N(5)O.H(2)O (L1.H(2)O) and C(16)H(12)N(6)O (L2), were synthesized by solvent-free aldol condensation at room temperature. L1, prepared by grinding picolinaldehyde with 2,3-diamino-3-isocyanoacrylonitrile in a 1:1 molar ratio, crystallized as a monohydrate. L2 was prepared by grinding picolinaldehyde with 2,3-diamino-3-isocyanoacrylonitrile in a 2:1 molar ratio. By varying the conditions of crystallization it was possible to obtain two polymorphs, viz. L2-I and L2-II; both crystallized in the monoclinic space group P2(1)/c. They differ in the orientation of one pyridine ring with respect to the plane of the imidazole ring. In L2-I, this ring is oriented towards and above the imidazole ring, while in L2-II it is rotated away from and below the imidazole ring. In all three molecules, there is a short intramolecular N-H...N contact inherent to the planarity of the systems. In L1.H(2)O, this involves an amino H atom and the C=N N atom, while in L2 it involve...
Acta crystallographica. Section C, Crystal structure communications, 2013
Reaction of biotin {C(10)H(16)N(2)O(3)S, HL; systematic name: 5-[(3aS,4S,6aR)-2-oxohexahydro-1H-t... more Reaction of biotin {C(10)H(16)N(2)O(3)S, HL; systematic name: 5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoic acid} with silver acetate and a few drops of aqueous ammonia leads to the deprotonation of the carboxylic acid group and the formation of a neutral chiral two-dimensional polymer network, poly[[{μ(3)-5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoato}silver(I)] trihydrate], {[Ag(C(10)H(15)N(2)O(3)S)]·3H(2)O}(n) or {[Ag(L)]·3H(2)O}(n), (I). Here, the Ag(I) cations are pentacoordinate, coordinated by four biotin anions via two S atoms and a ureido O atom, and by two carboxylate O atoms of the same molecule. The reaction of biotin with silver salts of potentially coordinating anions, viz. nitrate and perchlorate, leads to the formation of the chiral one-dimensional coordination polymers catena-poly[[bis[nitratosilver(I)]-bis{μ(3)-5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoato}] monohydrate], {[Ag(2)(NO(3))(2)(...
Polyhedron, 2010
Two-, three-and four-coordinate silver (I) complexes, AgX (X= CN−, PF6-, and SbF6-), with triphen... more Two-, three-and four-coordinate silver (I) complexes, AgX (X= CN−, PF6-, and SbF6-), with triphenyl phosphine, tricyclohexyl phosphine, diphenylcyclohexyl phosphine, and dicyclohexylphenyl phosphine have been synthesised and characterised by single crystal ...
![Research paper thumbnail of NMR and kinetic studies of the interactions of [Au( cis -DACH)Cl 2 ]Cl and [Au( cis -DACH) 2 ]Cl 3 with potassium cyanide in aqueous solution](https://attachments.academia-assets.com/51293625/thumbnails/1.jpg)
](Journal of Coordination Chemistry, 2014
NMR and kinetic studies of the interaction of [Au(cis-DACH)Cl2]Cl and [Au(cis-DACH)2]Cl3 with pot... more NMR and kinetic studies of the interaction of [Au(cis-DACH)Cl2]Cl and [Au(cis-DACH)2]Cl3 with potassium cyanide in aqueous solution
![Research paper thumbnail of Structural characterization of a cadmium(II)-sulfato complex, [Cd(N,N′-diethyl thiourea)4(SO4)]](https://attachments.academia-assets.com/51293623/thumbnails/1.jpg)
](Journal of Structural Chemistry, 2011
A cadmium(II) complex, tetrakis(N,N′-diethylthiourea)sulfatocadmium(II), [Cd(Detu) 4 SO 4 ] (1) i... more A cadmium(II) complex, tetrakis(N,N′-diethylthiourea)sulfatocadmium(II), [Cd(Detu) 4 SO 4 ] (1) is prepared and its crystal structure is determined by X-ray crystallography. The crystal structure of the complex consists of an independent molecule with the central cadmium atom coordinated to four thione sulfur atoms of Detu and two oxygen atoms of the sulfate ligand. The Cd atom has a pseudo-octahedral coordination environment with the cis angles varying from 57.68° to 126.57°, while the trans angles fall in the range of 142° to 169°. The new complex was also characterized by IR and NMR spectroscopy and the spectroscopic data are discussed in terms of the nature of bonding.
Acta Crystallographica Section E-structure Reports Online, 2006
![Research paper thumbnail of Mercury(II) complexes of pyrrolidinedithiocarbamate, crystal structure of bis{[μ 2 -(pyrrolidinedithiocarbamato- S , S ′)(pyrrolidinedithiocarbamato- S , S ′)mercury(II)]}](https://attachments.academia-assets.com/51293622/thumbnails/1.jpg)
](Journal of Coordination Chemistry, 2010
Journal of Coordination Chemistry, 2007
ABSTRACT The reactions of 3,6-bis(2′-pyridyl)-1,2,4,5-tetrazine (bptz) with HgX2 (X = Cl, Br, I) ... more ABSTRACT The reactions of 3,6-bis(2′-pyridyl)-1,2,4,5-tetrazine (bptz) with HgX2 (X = Cl, Br, I) have been investigated. The isolated complexes have been characterized by elemental analysis, conductivity measurements, IR, H, and C NMR spectroscopy. PM3 calculations show that the trans-conformation is preferred. Thermodynamic calculations and orbital energies are reported.
![Research paper thumbnail of Crystal Structure of a Trinuclear Mercury(II) Cyanide Complex of Tetramethylthiourea, [{(Tetramethylthiourea)2Hg(CN)2}2·Hg(CN)2]](https://attachments.academia-assets.com/51293609/thumbnails/1.jpg)
](Journal of Chemical Crystallography, 2010
The title compound was prepared by reacting mercury(II) cyanide and tetramethylthiourea (Tmtu) in... more The title compound was prepared by reacting mercury(II) cyanide and tetramethylthiourea (Tmtu) in the molar ratio of 1:1.75. It was characterized by IR and NMR ( 1 H and 13 C) spectroscopy, and X-ray crystallography.
Journal of Chemical Crystallography, 2010
CITATIONS 5 READS 31 7 authors, including: Some of the authors of this publication are also worki... more CITATIONS 5 READS 31 7 authors, including: Some of the authors of this publication are also working on these related projects: Mononuclear complexes of 3d metal ions with Schiff-bases derived from salicylaldehyde View project Saeed Ahmad Gomal University Abstract Reactions of N,N 0 -diethylthiourea (Detu) with copper(I) cyanide and copper(I) iodide in a 2:1 M ratio in acetonitrile resulted in the formation of [Cu(Detu)Cl] 3 Á (CH 3 CN) 0.5 (1) and [Cu(Detu) 3 I] , respectively. In compound 1 each copper atom is coordinated with one sulfur atom of Detu and with one chloride ion forming a centrosymmetric trinuclear core (Cu 3 S 3 Cl 3 ) that exhibits a Cu-Cu separation of 2.7383(5) Ǻ indicating the existence of cuprophilic interactions. Complex 2 crystallizes with two independent molecules per asymmetric unit. Each copper atom is coordinated with three sulfur atoms of Detu and with one iodide ion in a tetrahedral arrangement.
Inorganica Chimica Acta, 2012
The user has requested enhancement of the downloaded file.
Inorganica Chimica Acta, 2010
Acta Crystallographica Section E-structure Reports Online, 2006
Crystallography Reports, 2013
Two mercury(II) complexes containing cyanide and, N,N' diethylthiourea (detu) and N,N' dipropylth... more Two mercury(II) complexes containing cyanide and, N,N' diethylthiourea (detu) and N,N' dipropylthiourea (dprtu) ligands, [(detu) 2 Hg(CN) 2 ] (1) and [(dprtu) 2 Hg(CN) 2 ] (2), respectively, have been prepared and characterized by X ray crystallography. In the both complexes Hg atom lies on a 2 fold rotation axis, and is coordinated to the sulfur atoms of two thiourea ligands and to two cyanide carbon atoms. Both have a distorted tetrahedral environment with bond angles about the Hg atoms in the range of 93.41(4)°-146.75(19)°. In the crystal structures symmetry related molecules are linked via N-H-N hydrogen bonds resulting in the formation of a two dimensional network in 1, while in 2 a double stranded one dimensional chain is formed.
Acta Crystallographica Section E Structure Reports Online, 2009
Key indicators: single-crystal X-ray study; T = 173 K; mean (C-C) = 0.003 Å; R factor = 0.052; wR... more Key indicators: single-crystal X-ray study; T = 173 K; mean (C-C) = 0.003 Å; R factor = 0.052; wR factor = 0.143; data-to-parameter ratio = 11.9.
Gold(I) complexes of 2-(diphenylphosphanyl)ethylamine or (2-aminoethyl)diphenylphosphine (AEP), a... more Gold(I) complexes of 2-(diphenylphosphanyl)ethylamine or (2-aminoethyl)diphenylphosphine (AEP), and dithiocaarbamates (R 2 NCS 2) were prepared by the reaction of these ligands with (CH 3) 2 S-AuCl in dichloromethane. The synthesized complexes [Au(AEP)Cl] (1), [Au(AEP) 2 ]Cl (2), and [Au 2 (R 2 NCS 2) 2 ] n (R 2 = di-methyl (3), diethyl (4), and dibenzyl (5)) were characterized by ele
Journal of Chemical Crystallography, 2011
Acta Crystallogr E Struct Rep, 2006
Single-crystal X-ray study T = 173 K Mean (C-C) = 0.003 Å R factor = 0.039 wR factor = 0.086 Data... more Single-crystal X-ray study T = 173 K Mean (C-C) = 0.003 Å R factor = 0.039 wR factor = 0.086 Data-to-parameter ratio = 20.0
Acta Crystallogr E Struct Rep, 2010
Inorganic Reaction Mechanisms, 2006
Acta crystallographica. Section C, Crystal structure communications, 2010
The title compounds, C(10)H(9)N(5)O.H(2)O (L1.H(2)O) and C(16)H(12)N(6)O (L2), were synthesized b... more The title compounds, C(10)H(9)N(5)O.H(2)O (L1.H(2)O) and C(16)H(12)N(6)O (L2), were synthesized by solvent-free aldol condensation at room temperature. L1, prepared by grinding picolinaldehyde with 2,3-diamino-3-isocyanoacrylonitrile in a 1:1 molar ratio, crystallized as a monohydrate. L2 was prepared by grinding picolinaldehyde with 2,3-diamino-3-isocyanoacrylonitrile in a 2:1 molar ratio. By varying the conditions of crystallization it was possible to obtain two polymorphs, viz. L2-I and L2-II; both crystallized in the monoclinic space group P2(1)/c. They differ in the orientation of one pyridine ring with respect to the plane of the imidazole ring. In L2-I, this ring is oriented towards and above the imidazole ring, while in L2-II it is rotated away from and below the imidazole ring. In all three molecules, there is a short intramolecular N-H...N contact inherent to the planarity of the systems. In L1.H(2)O, this involves an amino H atom and the C=N N atom, while in L2 it involve...
Acta crystallographica. Section C, Crystal structure communications, 2013
Reaction of biotin {C(10)H(16)N(2)O(3)S, HL; systematic name: 5-[(3aS,4S,6aR)-2-oxohexahydro-1H-t... more Reaction of biotin {C(10)H(16)N(2)O(3)S, HL; systematic name: 5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoic acid} with silver acetate and a few drops of aqueous ammonia leads to the deprotonation of the carboxylic acid group and the formation of a neutral chiral two-dimensional polymer network, poly[[{μ(3)-5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoato}silver(I)] trihydrate], {[Ag(C(10)H(15)N(2)O(3)S)]·3H(2)O}(n) or {[Ag(L)]·3H(2)O}(n), (I). Here, the Ag(I) cations are pentacoordinate, coordinated by four biotin anions via two S atoms and a ureido O atom, and by two carboxylate O atoms of the same molecule. The reaction of biotin with silver salts of potentially coordinating anions, viz. nitrate and perchlorate, leads to the formation of the chiral one-dimensional coordination polymers catena-poly[[bis[nitratosilver(I)]-bis{μ(3)-5-[(3aS,4S,6aR)-2-oxohexahydro-1H-thieno[3,4-d]imidazol-4-yl]pentanoato}] monohydrate], {[Ag(2)(NO(3))(2)(...
Polyhedron, 2010
Two-, three-and four-coordinate silver (I) complexes, AgX (X= CN−, PF6-, and SbF6-), with triphen... more Two-, three-and four-coordinate silver (I) complexes, AgX (X= CN−, PF6-, and SbF6-), with triphenyl phosphine, tricyclohexyl phosphine, diphenylcyclohexyl phosphine, and dicyclohexylphenyl phosphine have been synthesised and characterised by single crystal ...
Journal of Coordination Chemistry, 2014
NMR and kinetic studies of the interaction of [Au(cis-DACH)Cl2]Cl and [Au(cis-DACH)2]Cl3 with pot... more NMR and kinetic studies of the interaction of [Au(cis-DACH)Cl2]Cl and [Au(cis-DACH)2]Cl3 with potassium cyanide in aqueous solution
Journal of Structural Chemistry, 2011
A cadmium(II) complex, tetrakis(N,N′-diethylthiourea)sulfatocadmium(II), [Cd(Detu) 4 SO 4 ] (1) i... more A cadmium(II) complex, tetrakis(N,N′-diethylthiourea)sulfatocadmium(II), [Cd(Detu) 4 SO 4 ] (1) is prepared and its crystal structure is determined by X-ray crystallography. The crystal structure of the complex consists of an independent molecule with the central cadmium atom coordinated to four thione sulfur atoms of Detu and two oxygen atoms of the sulfate ligand. The Cd atom has a pseudo-octahedral coordination environment with the cis angles varying from 57.68° to 126.57°, while the trans angles fall in the range of 142° to 169°. The new complex was also characterized by IR and NMR spectroscopy and the spectroscopic data are discussed in terms of the nature of bonding.
Acta Crystallographica Section E-structure Reports Online, 2006
Journal of Coordination Chemistry, 2010
Journal of Coordination Chemistry, 2007
ABSTRACT The reactions of 3,6-bis(2′-pyridyl)-1,2,4,5-tetrazine (bptz) with HgX2 (X = Cl, Br, I) ... more ABSTRACT The reactions of 3,6-bis(2′-pyridyl)-1,2,4,5-tetrazine (bptz) with HgX2 (X = Cl, Br, I) have been investigated. The isolated complexes have been characterized by elemental analysis, conductivity measurements, IR, H, and C NMR spectroscopy. PM3 calculations show that the trans-conformation is preferred. Thermodynamic calculations and orbital energies are reported.
Journal of Chemical Crystallography, 2010
The title compound was prepared by reacting mercury(II) cyanide and tetramethylthiourea (Tmtu) in... more The title compound was prepared by reacting mercury(II) cyanide and tetramethylthiourea (Tmtu) in the molar ratio of 1:1.75. It was characterized by IR and NMR ( 1 H and 13 C) spectroscopy, and X-ray crystallography.
Journal of Chemical Crystallography, 2010
CITATIONS 5 READS 31 7 authors, including: Some of the authors of this publication are also worki... more CITATIONS 5 READS 31 7 authors, including: Some of the authors of this publication are also working on these related projects: Mononuclear complexes of 3d metal ions with Schiff-bases derived from salicylaldehyde View project Saeed Ahmad Gomal University Abstract Reactions of N,N 0 -diethylthiourea (Detu) with copper(I) cyanide and copper(I) iodide in a 2:1 M ratio in acetonitrile resulted in the formation of [Cu(Detu)Cl] 3 Á (CH 3 CN) 0.5 (1) and [Cu(Detu) 3 I] , respectively. In compound 1 each copper atom is coordinated with one sulfur atom of Detu and with one chloride ion forming a centrosymmetric trinuclear core (Cu 3 S 3 Cl 3 ) that exhibits a Cu-Cu separation of 2.7383(5) Ǻ indicating the existence of cuprophilic interactions. Complex 2 crystallizes with two independent molecules per asymmetric unit. Each copper atom is coordinated with three sulfur atoms of Detu and with one iodide ion in a tetrahedral arrangement.
Inorganica Chimica Acta, 2012
The user has requested enhancement of the downloaded file.
Inorganica Chimica Acta, 2010
Acta Crystallographica Section E-structure Reports Online, 2006
Crystallography Reports, 2013
Two mercury(II) complexes containing cyanide and, N,N' diethylthiourea (detu) and N,N' dipropylth... more Two mercury(II) complexes containing cyanide and, N,N' diethylthiourea (detu) and N,N' dipropylthiourea (dprtu) ligands, [(detu) 2 Hg(CN) 2 ] (1) and [(dprtu) 2 Hg(CN) 2 ] (2), respectively, have been prepared and characterized by X ray crystallography. In the both complexes Hg atom lies on a 2 fold rotation axis, and is coordinated to the sulfur atoms of two thiourea ligands and to two cyanide carbon atoms. Both have a distorted tetrahedral environment with bond angles about the Hg atoms in the range of 93.41(4)°-146.75(19)°. In the crystal structures symmetry related molecules are linked via N-H-N hydrogen bonds resulting in the formation of a two dimensional network in 1, while in 2 a double stranded one dimensional chain is formed.
Acta Crystallographica Section E Structure Reports Online, 2009
Key indicators: single-crystal X-ray study; T = 173 K; mean (C-C) = 0.003 Å; R factor = 0.052; wR... more Key indicators: single-crystal X-ray study; T = 173 K; mean (C-C) = 0.003 Å; R factor = 0.052; wR factor = 0.143; data-to-parameter ratio = 11.9.