History of coordination chemistry
An Overview of coordination chemistry
Historically, inorganic chemistry is the oldest branch of chemistry. Classical inorganic chemistry was primarily concerned with the preparation and studies of the properties of all the elements and their compounds, including the simple compounds of carbon.
It is very difficult to determine the exact date of preparation of the first coordination compound. The chemistry of complexes may be said to have originated in 1704 with the discovery of Prussian blue by Diesbach, a colour maker. After this one might site the investigation of the products of oxidation of ammonical cobalt solution of Tassaert (1799). In the years that followed, Cleve, Wolcott Gibbs, Blomstrand and Fermy did a large amount of effort towards the study of complexes.
By 1870, a great deal of information on the complexes had been gathered and it was Prof.Jorgenson who for the first time methodized much of this field by the preparation and characterization of a large number of complex compounds.
An understanding of coordination compounds and their properties began with the work of Alfred Werner. In 1893, Werner proposed an interpretation of coordination compounds which emphasized the number and nature of the groups attached to the metal ion. Werner’s theory represent a quantum jump in the history of coordination chemistry, and the most of the 20th century contributions to coordination chemistry has been developments, extensions or confirmation of Werner’s theory rather than ideas incompatible with, or opposed to it. Since its promulgation and general acceptance over the decades between 1890 and 1910, it has provided a central trunk from which many fruitful branches of transition chemistry have grown and flourished.
His theory replaced the older concepts of Berzelius (1819), Grohen (1837), Claus (1856), Blomstrand (1869) and Jorgenson (1894) and became a fundamental part of the electronic theory of valency formulated by G.N.Lewis (1916) and applied extensively to coordination compounds by N.V.Sidgwick (1927).
Revival of classical crystal field theory (Bethe, 1929) and its further sophistication in to the ligand field theory by Orgel, Jorgenson, Ballhausen and others during the 1950s to early 1960s is another significant advancement which could provide quantitative interpretations of the features of spectra and several other properties of transition metal compounds that was hardly possible on the basis of the valence bond concept of Pauling (1931) despite initial success of Pauling’s view to explain in general the stereochemistry and gross magnetic behaviour of transition metal compounds.
One may immediately ask why this group of compounds should be singled out for special study. There are several answers to such a question but some of these are outlined below:
a) These compounds are formed by large number of elements.
b) Their applications more numerous than might be expected and many new applications are being discovered.
c) Many chemical phenomena are exhibited to a superlative degree by these compounds ( i.e., molecular rotation of polarized light )
The growth of the coordination chemistry has been three dimensional, encompassing breadth, depth and applications. The ongoing respect for the evolving science is apparent in the five Nobel prizes that have been impinged heavily on the subject (A. Werner, 1913; M.Eigen, 1967, Wilkinson and Fischer, 1973; H.Taube, 1983; Cram, Lehn and Pederson, 1987). The first (Werner) and last (Cram, Lehn and Pederson) in the list recognized the old and the new realms of coordination chemistry specifically.
The steady improvement in synthetic methodology allows us to forsee coordination chemistry entering a phase of relative rather than investigative chemistry. The development of complexes for application in medicine is an obvious example. The use of metal complexes in therapy and diagnostic imaging is increasing. Throughout history, both ancient and modern, metal compounds have been used in medicine to treat a variety of ailments and a remarkable example being cis-platin, cis-PtCl2(NH3)2, introduced by Rosenberg.This discovery led to a veritable avalanche of research in platinum chemistry and for a continuing search for the most effective anticancer drug.
The chelation plays a definite role in the cause and treatment of a cancer is a significant development of the 1960s.
A triplatinum complex (Fig-1) was shown to be cytotoxic at nanomolar levels for several different concentrations allowing for the potential to dose at much lower concentrations than cisplatin. It has also shown potential in treating g1 malignancies which have been otherwise untreatable using cisplatin. This compound is licensed to Novus pharma and is currently undergoing phase II clinical trial for the treatment of several different cancers.
Gold compounds like Auronofin, (2,3,4,6-tetra-o-acetyl-1-thio-β-D-glucopyranoside-5) triethyl phosphine gold(I) are applied as oral drugs against rheumatoid arthritis.
Coordination chemistry has its greatest application in the field of hydrometallurgy and pyrometallurgical operations. Use of carboxylic acid extractant to recover nickel and cobalt and for removal of iron (III) from solution of rare earth metals has been reported. Versatic acid has been used for the production of pure Eu (III). La (III), Yb (III) oxide and to recover indium and gallium from solutions obtained from leaching of bauxites, zinc minerals and coal ash. Solvent extraction of copper and nickel by ortho hydroxyl oximes is used widely throughout the world.
Many metal complexes find applications in the field of catalysis. Among the top performers in this class ( and the elements involved) are the Wilkinson catalyst for the hydroformylation reaction (Rh), the conversion of ethylene to acetaldehyde (Pd) and olefin polymerization (Zr, Ni); there are many others too numerous to mention. It should also be noted that one of the greatest recent advances in organic chemistry, is asymmetric synthesis, depends entirely upon transitional metal atoms as the catalytic centres.
The ever increasing applications of metal complexes in various fields of science are the driving force for the research and development of coordination chemistry. In present study the coordination chemistry of ruthenium was studied.
Historically, inorganic chemistry is the oldest branch of chemistry. Classical inorganic chemistry was primarily concerned with the preparation and studies of the properties of all the elements and their compounds, including the simple compounds of carbon.
It is very difficult to determine the exact date of preparation of the first coordination compound. The chemistry of complexes may be said to have originated in 1704 with the discovery of Prussian blue by Diesbach, a colour maker. After this one might site the investigation of the products of oxidation of ammonical cobalt solution of Tassaert (1799). In the years that followed, Cleve, Wolcott Gibbs, Blomstrand and Fermy did a large amount of effort towards the study of complexes.
By 1870, a great deal of information on the complexes had been gathered and it was Prof.Jorgenson who for the first time methodized much of this field by the preparation and characterization of a large number of complex compounds.
An understanding of coordination compounds and their properties began with the work of Alfred Werner. In 1893, Werner proposed an interpretation of coordination compounds which emphasized the number and nature of the groups attached to the metal ion. Werner’s theory represent a quantum jump in the history of coordination chemistry, and the most of the 20th century contributions to coordination chemistry has been developments, extensions or confirmation of Werner’s theory rather than ideas incompatible with, or opposed to it. Since its promulgation and general acceptance over the decades between 1890 and 1910, it has provided a central trunk from which many fruitful branches of transition chemistry have grown and flourished.
His theory replaced the older concepts of Berzelius (1819), Grohen (1837), Claus (1856), Blomstrand (1869) and Jorgenson (1894) and became a fundamental part of the electronic theory of valency formulated by G.N.Lewis (1916) and applied extensively to coordination compounds by N.V.Sidgwick (1927).
Revival of classical crystal field theory (Bethe, 1929) and its further sophistication in to the ligand field theory by Orgel, Jorgenson, Ballhausen and others during the 1950s to early 1960s is another significant advancement which could provide quantitative interpretations of the features of spectra and several other properties of transition metal compounds that was hardly possible on the basis of the valence bond concept of Pauling (1931) despite initial success of Pauling’s view to explain in general the stereochemistry and gross magnetic behaviour of transition metal compounds.
One may immediately ask why this group of compounds should be singled out for special study. There are several answers to such a question but some of these are outlined below:
a) These compounds are formed by large number of elements.
b) Their applications more numerous than might be expected and many new applications are being discovered.
c) Many chemical phenomena are exhibited to a superlative degree by these compounds ( i.e., molecular rotation of polarized light )
The growth of the coordination chemistry has been three dimensional, encompassing breadth, depth and applications. The ongoing respect for the evolving science is apparent in the five Nobel prizes that have been impinged heavily on the subject (A. Werner, 1913; M.Eigen, 1967, Wilkinson and Fischer, 1973; H.Taube, 1983; Cram, Lehn and Pederson, 1987). The first (Werner) and last (Cram, Lehn and Pederson) in the list recognized the old and the new realms of coordination chemistry specifically.
The steady improvement in synthetic methodology allows us to forsee coordination chemistry entering a phase of relative rather than investigative chemistry. The development of complexes for application in medicine is an obvious example. The use of metal complexes in therapy and diagnostic imaging is increasing. Throughout history, both ancient and modern, metal compounds have been used in medicine to treat a variety of ailments and a remarkable example being cis-platin, cis-PtCl2(NH3)2, introduced by Rosenberg.This discovery led to a veritable avalanche of research in platinum chemistry and for a continuing search for the most effective anticancer drug.
The chelation plays a definite role in the cause and treatment of a cancer is a significant development of the 1960s.
A triplatinum complex (Fig-1) was shown to be cytotoxic at nanomolar levels for several different concentrations allowing for the potential to dose at much lower concentrations than cisplatin. It has also shown potential in treating g1 malignancies which have been otherwise untreatable using cisplatin. This compound is licensed to Novus pharma and is currently undergoing phase II clinical trial for the treatment of several different cancers.
Gold compounds like Auronofin, (2,3,4,6-tetra-o-acetyl-1-thio-β-D-glucopyranoside-5) triethyl phosphine gold(I) are applied as oral drugs against rheumatoid arthritis.
Coordination chemistry has its greatest application in the field of hydrometallurgy and pyrometallurgical operations. Use of carboxylic acid extractant to recover nickel and cobalt and for removal of iron (III) from solution of rare earth metals has been reported. Versatic acid has been used for the production of pure Eu (III). La (III), Yb (III) oxide and to recover indium and gallium from solutions obtained from leaching of bauxites, zinc minerals and coal ash. Solvent extraction of copper and nickel by ortho hydroxyl oximes is used widely throughout the world.
Many metal complexes find applications in the field of catalysis. Among the top performers in this class ( and the elements involved) are the Wilkinson catalyst for the hydroformylation reaction (Rh), the conversion of ethylene to acetaldehyde (Pd) and olefin polymerization (Zr, Ni); there are many others too numerous to mention. It should also be noted that one of the greatest recent advances in organic chemistry, is asymmetric synthesis, depends entirely upon transitional metal atoms as the catalytic centres.
The ever increasing applications of metal complexes in various fields of science are the driving force for the research and development of coordination chemistry. In present study the coordination chemistry of ruthenium was studied.
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