11_chapter 1
... living matter viz; chlorophyll’s (Mg(II) complex) and haemoglobin (Fe(II) complex) (Vernon and Seely 1966). A large number of metal proteins and other metal complexes of biological importance have been studied. Apart from biological field, co-ordination compounds play an essential role in chemical i ...
... living matter viz; chlorophyll’s (Mg(II) complex) and haemoglobin (Fe(II) complex) (Vernon and Seely 1966). A large number of metal proteins and other metal complexes of biological importance have been studied. Apart from biological field, co-ordination compounds play an essential role in chemical i ...
Metal aqua ions
... In the solid state, the H-atoms of the coordinated waters are almost always H-bonded to other waters, or anions such as nitrate or perchlorate. In aqueous solution, this H-bonding structures the water molecules around the aqua ion into what is called the ‘outer-sphere’ of solvating water molecules, ...
... In the solid state, the H-atoms of the coordinated waters are almost always H-bonded to other waters, or anions such as nitrate or perchlorate. In aqueous solution, this H-bonding structures the water molecules around the aqua ion into what is called the ‘outer-sphere’ of solvating water molecules, ...
Carbohydrate-Metal Complexes : Structural Chemistry of Stable
... in the homoleptic borate ester 17 with doubly deprotonated D - and L -threitol in which the deprotonation occurs at the chelating central threo-configured diol group. Depending on the involved enantiomeric pairs of threitol (17 presents the (R,R)-(R,R) form), three different complexes are formed. Th ...
... in the homoleptic borate ester 17 with doubly deprotonated D - and L -threitol in which the deprotonation occurs at the chelating central threo-configured diol group. Depending on the involved enantiomeric pairs of threitol (17 presents the (R,R)-(R,R) form), three different complexes are formed. Th ...
This salt`s solubility is pH dependent. How? * In a BASIC solution
... If a compound is BASIC, then it will be LESS SOLUBLE in basic solutions, and MORE SOLUBLE in acidic solutions! If a compound is ACIDIC, then it will be MORE SOLUBLE in basic solutions, and LESS SOLUBLE in acidic solutions! If a compound is NEUTRAL (neither acidic nor basic), then its solubility will ...
... If a compound is BASIC, then it will be LESS SOLUBLE in basic solutions, and MORE SOLUBLE in acidic solutions! If a compound is ACIDIC, then it will be MORE SOLUBLE in basic solutions, and LESS SOLUBLE in acidic solutions! If a compound is NEUTRAL (neither acidic nor basic), then its solubility will ...
Coordination Chemistry and Ligand Exchange reactions in the
... According to Wener, in co-ordination compounds, the central metal atoms exhibit primary and secondary valencies. 1. The primary valency is ionizable. Secondary valency is not ionizable. - The primary valency corresponds to the oxidation state - The secondary valency corresponds to the coordination n ...
... According to Wener, in co-ordination compounds, the central metal atoms exhibit primary and secondary valencies. 1. The primary valency is ionizable. Secondary valency is not ionizable. - The primary valency corresponds to the oxidation state - The secondary valency corresponds to the coordination n ...
Scaffold hopping
... relationships between two or three single bonds (vectors) is used to search a database of chemical structures for suitable alternative fragments fitting onto these vectors. CAVEAT applications have been reported in the literature since the early 1990s (see [31] and the CAVEAT home page). A third app ...
... relationships between two or three single bonds (vectors) is used to search a database of chemical structures for suitable alternative fragments fitting onto these vectors. CAVEAT applications have been reported in the literature since the early 1990s (see [31] and the CAVEAT home page). A third app ...
Diverse Chemical Applications of N
... a macrocycle that is eventually ejected from the metal, producing polymer rings of about 150 kDa. Fréchet has used a specially designed Ru-tethered NHC catalyst for the synthesis of a cyclic dendronized polymer from a dendronized macromonomer.6 The combination of tether size and NHC saturation was ...
... a macrocycle that is eventually ejected from the metal, producing polymer rings of about 150 kDa. Fréchet has used a specially designed Ru-tethered NHC catalyst for the synthesis of a cyclic dendronized polymer from a dendronized macromonomer.6 The combination of tether size and NHC saturation was ...
University of Groningen Magnesium and zinc hydride
... transition metal, due to its position in the periodic table, it is a special case on account of its d10 electron configuration. A number of zinc complexes are known and various zinc compounds have been applied in catalytic reactions. However, as a consequence of the filled d-orbitals, zinc often beh ...
... transition metal, due to its position in the periodic table, it is a special case on account of its d10 electron configuration. A number of zinc complexes are known and various zinc compounds have been applied in catalytic reactions. However, as a consequence of the filled d-orbitals, zinc often beh ...
Voltammetric Determination of Trace Concentrations of Metals in the
... Tl(III), and Sb(V) are nontoxic, whereas As(III), Cr(VI), Tl(I), and Sb(III) are toxic (20,21). However, these pairs of oxidation states can be distinguished electrochemically, since only one of each pair is electrochemically active (22). The concentration of the electroinactive oxidation state can ...
... Tl(III), and Sb(V) are nontoxic, whereas As(III), Cr(VI), Tl(I), and Sb(III) are toxic (20,21). However, these pairs of oxidation states can be distinguished electrochemically, since only one of each pair is electrochemically active (22). The concentration of the electroinactive oxidation state can ...
Tetrahedral, Highly Coordinatively Unsaturated 14e (Fe) and 15e
... the nickel complex 2iPr2Ni. In general, tetrahedral TpR′Co-X species show d-d transitions of >300 in the range of 500-600 nm (Figure 2b; cf. 6iPr2Co; for details, see below), but an UV-vis spectrum of the dark orange 2iPr2Co contains a very weak absorption at 647 nm ( 40; Figure 2a), suggesting t ...
... the nickel complex 2iPr2Ni. In general, tetrahedral TpR′Co-X species show d-d transitions of >300 in the range of 500-600 nm (Figure 2b; cf. 6iPr2Co; for details, see below), but an UV-vis spectrum of the dark orange 2iPr2Co contains a very weak absorption at 647 nm ( 40; Figure 2a), suggesting t ...
OXOVANADIUM(IV) COMPLEXES WITH LIGANDS DERIVED BY
... The synthesis of a new parent oxovanadium(IV) complex, [VO(L)]SO4, is achieved under in-situ experimental conditions where vanadyl ion acts as a kinetic template for the ligand derived by condensation of 1,2-diacetylbenzene with 2-aminobenzamide in 1:2 molar ratio in aqueous ethanol medium. The pare ...
... The synthesis of a new parent oxovanadium(IV) complex, [VO(L)]SO4, is achieved under in-situ experimental conditions where vanadyl ion acts as a kinetic template for the ligand derived by condensation of 1,2-diacetylbenzene with 2-aminobenzamide in 1:2 molar ratio in aqueous ethanol medium. The pare ...
NOVEL IRON(II) TRIAZOLE-PYRIDINE BASED DINUCLEAR COMPLEXES: SYNTHESIS, CHARACTERIZATION AND MAGNETIC PROPERTIES
... group. The methyl group in the position 6 of the pyridine group is introduced to induce steric hindrance in the complexes and decrease the ligand field strength. As a result, the influence of the methyl group may induce SCO in low spin (LS) complexes, or tune the SCO properties (such as transition h ...
... group. The methyl group in the position 6 of the pyridine group is introduced to induce steric hindrance in the complexes and decrease the ligand field strength. As a result, the influence of the methyl group may induce SCO in low spin (LS) complexes, or tune the SCO properties (such as transition h ...
- WRAP: Warwick Research Archive Portal
... 2,6-(PtBu2CH2)2–C5H3N) is particularly notable in this regard, undergoing C–H bond oxidative addition of fluorobenzene following dissociation of COE (Scheme 1).8 The reaction however lacks regioselectivity; selectivity that can be induced in analogous reactions with chloro- and bromo-benzene, throug ...
... 2,6-(PtBu2CH2)2–C5H3N) is particularly notable in this regard, undergoing C–H bond oxidative addition of fluorobenzene following dissociation of COE (Scheme 1).8 The reaction however lacks regioselectivity; selectivity that can be induced in analogous reactions with chloro- and bromo-benzene, throug ...
Antimicrobial activity of some of chlorocobaloximes containing
... containing 4-cynaopyridine as the axial ligand showed potential inhibition of bacterial growth. The activity of the complexes can be explained on the basis of chelation theory. On chelation , the polarity of the metal ion may be reduced to a greater extent due to the overlap of the ligand orbital an ...
... containing 4-cynaopyridine as the axial ligand showed potential inhibition of bacterial growth. The activity of the complexes can be explained on the basis of chelation theory. On chelation , the polarity of the metal ion may be reduced to a greater extent due to the overlap of the ligand orbital an ...
IOSR Journal of Applied Chemistry (IOSR-JAC) e-ISSN: 2278-5736.
... Coordination chemistry of Cu(II) and Ni(II) complexes of chelating ligands has been growing interest for their structures, spectral, and redox properties [1]. Large number of Cu(II) and Ni(II) complexes with different chelating ligands were reported and such complexes have shown significant antibact ...
... Coordination chemistry of Cu(II) and Ni(II) complexes of chelating ligands has been growing interest for their structures, spectral, and redox properties [1]. Large number of Cu(II) and Ni(II) complexes with different chelating ligands were reported and such complexes have shown significant antibact ...
synthesis, characterization and antibacterial activity of mixed ligand
... were recorded for KBr discs over the range 4000ñ400 cm-1. On the basis of the reported infrared spectra of amino acids, 8-hydroxyquinoline and their metal complexes (20ñ22), some of the important bands have been assigned (Tab. 4). A broad band observed in the region between 3460ñ3431 cm-1 is due to ...
... were recorded for KBr discs over the range 4000ñ400 cm-1. On the basis of the reported infrared spectra of amino acids, 8-hydroxyquinoline and their metal complexes (20ñ22), some of the important bands have been assigned (Tab. 4). A broad band observed in the region between 3460ñ3431 cm-1 is due to ...
Family of Cofacial Bimetallic Complexes of a Hexaanionic Carboxamide Cryptand
... the carboxamide hydrogen atoms were taken from the difference Fourier synthesis, and the hydrogen atoms were subsequently refined semifreely, restraining the NH distances to 0.88 Å, while constraining their Uiso values to 1.2 times the Ueq of the respective nitrogen atoms. This structure illustrate ...
... the carboxamide hydrogen atoms were taken from the difference Fourier synthesis, and the hydrogen atoms were subsequently refined semifreely, restraining the NH distances to 0.88 Å, while constraining their Uiso values to 1.2 times the Ueq of the respective nitrogen atoms. This structure illustrate ...
Synthesis of Chiral C2-symmetric Palladium and Rhodium SCS
... The control of the ligating properties of metal centers of metal catalyst with a well defined ligand system is one of the important goals of organic chemistry. Chiral pincer complexes consist of an enantiopure tridentate skeleton bound to a metal by at least one metal-carbon σ bond.1 The highly prot ...
... The control of the ligating properties of metal centers of metal catalyst with a well defined ligand system is one of the important goals of organic chemistry. Chiral pincer complexes consist of an enantiopure tridentate skeleton bound to a metal by at least one metal-carbon σ bond.1 The highly prot ...
197. States or Numbers - Department of Chemistry
... states/numbers are always represented using Roman numerals and never using Arabic numerals, though I am fully aware that most textbooks violate this injunction. Indeed the Freshman textbook used at Cincinnati totally inverts the conflicting IUPAC definitions which are the subject of Dr. Loock’s insi ...
... states/numbers are always represented using Roman numerals and never using Arabic numerals, though I am fully aware that most textbooks violate this injunction. Indeed the Freshman textbook used at Cincinnati totally inverts the conflicting IUPAC definitions which are the subject of Dr. Loock’s insi ...
Complexometric titration
... more than one complex in solution during the titration process. 3. a complexometric indicator capable of locating equivalence point with fair accuracy is available. In practice, the use of EDTA as a titrant is well established ...
... more than one complex in solution during the titration process. 3. a complexometric indicator capable of locating equivalence point with fair accuracy is available. In practice, the use of EDTA as a titrant is well established ...
Recent advances in understanding blue copper proteins
... The blue Cu (BC) or type 1 (T1) proteins [1] carry out electron transfer (ET) [2–5] in a wide variety of biological systems with variable enzymatic architectures. From the early days of bioinorganic chemistry researchers were fascinated by the unique spectral features of the BC proteins [1]. An inte ...
... The blue Cu (BC) or type 1 (T1) proteins [1] carry out electron transfer (ET) [2–5] in a wide variety of biological systems with variable enzymatic architectures. From the early days of bioinorganic chemistry researchers were fascinated by the unique spectral features of the BC proteins [1]. An inte ...
Speciation in Metal Toxicity and Metal-Based Therapeutics
... speciation. Our approach in this review will be to introduce the importance of speciation with a particularly rich example, that of nickel, and then present some definitions and concepts related to metal speciation and metal toxicity, with brief examples of how different structural levels of speciat ...
... speciation. Our approach in this review will be to introduce the importance of speciation with a particularly rich example, that of nickel, and then present some definitions and concepts related to metal speciation and metal toxicity, with brief examples of how different structural levels of speciat ...
Complexometric titrations
... as COOH, SO3H, NH2 and OH. When both acidic and basic groups are present, the complex will be soluble over a wide range of pH. When hydrophilic groups are absent, the solubilities of both the chelating agent and the metal chelate will be low, but they will be soluble in organic solvents. The term se ...
... as COOH, SO3H, NH2 and OH. When both acidic and basic groups are present, the complex will be soluble over a wide range of pH. When hydrophilic groups are absent, the solubilities of both the chelating agent and the metal chelate will be low, but they will be soluble in organic solvents. The term se ...
REACTIONS OF IRON(II)
... • complex transition metal ions are stable in acid solution • complex ions tend to be less stable in alkaline solution • in alkaline conditions they form neutral hydroxides and/or anionic complexes • it is easier to remove electrons from neutral or negatively charged species • alkaline conditions ar ...
... • complex transition metal ions are stable in acid solution • complex ions tend to be less stable in alkaline solution • in alkaline conditions they form neutral hydroxides and/or anionic complexes • it is easier to remove electrons from neutral or negatively charged species • alkaline conditions ar ...
IOSR Journal of Applied Chemistry (IOSR-JAC)
... antiprismatic geometry becomes favourable. Since in the complexes [Mn2(4-MPipzcdtH)6(O2)2](X)4 (X = ClO4, Cl) both the 4-methylpiperazine-1-carbodithioic acid and O2- ligands have small bite, D2d geometry should be preferred. It is expected that the D2d low symmetry should lead to magnetic moments n ...
... antiprismatic geometry becomes favourable. Since in the complexes [Mn2(4-MPipzcdtH)6(O2)2](X)4 (X = ClO4, Cl) both the 4-methylpiperazine-1-carbodithioic acid and O2- ligands have small bite, D2d geometry should be preferred. It is expected that the D2d low symmetry should lead to magnetic moments n ...
Ligand
In coordination chemistry, a ligand (/lɪɡənd/) is an ion or molecule (functional group) that binds to a central metal atom to form a coordination complex. The bonding between metal and ligand generally involves formal donation of one or more of the ligand's electron pairs. The nature of metal-ligand bonding can range from covalent to ionic. Furthermore, the metal-ligand bond order can range from one to three. Ligands are viewed as Lewis bases, although rare cases are known to involve Lewis acidic ""ligand.""Metals and metalloids are bound to ligands in virtually all circumstances, although gaseous ""naked"" metal ions can be generated in high vacuum. Ligands in a complex dictate the reactivity of the central atom, including ligand substitution rates, the reactivity of the ligands themselves, and redox. Ligand selection is a critical consideration in many practical areas, including bioinorganic and medicinal chemistry, homogeneous catalysis, and environmental chemistry.Ligands are classified in many ways like : their charge, their size (bulk), the identity of the coordinating atom(s), and the number of electrons donated to the metal (denticity or hapticity). The size of a ligand is indicated by its cone angle.