Coordination complexes/compounds

Coordination Compounds (Complexes). See Ammine or Ammoniate and Coordination, Vol 1, pA275... 

Additionally to the theoretical data and synthetic techniques for various metal complexes presented in Chaps. 2-A, we would like to pay special attention to three kinds of coordination compounds (complexes of phthalocyanines, quinones, and radioactive elements), whose syntheses, in our opinion, have been insufficiently generalized in monographs and textbooks on synthetic coordination chemistry. This choice is caused by the facts that phthalocyanines, as n-aromatic macrocyclic compounds, possess unusual thermal stability (nonstandard for organic and organometallic species) the quinone complexes have free-radical properties and coordination and organometallic compounds of radioactive elements are interesting at least for the reasons of necessity of special precautions in their syntheses and applications in the nuclear industry and nuclear medicine. So, this chapter is dedicated to the peculiarities of structure and properties and the main synthetic procedures for the complexes above. 

Electron donation-acceptance reactions, which are considered to be Lewis acid-base interactions, also include the formation of coordination compounds, complex formation through hydrogen bonding, charge transfer complex formation, and so on. It should be apparent that the Lewis theory of acids and bases encompasses a great deal of both inorganic and organic chemistry. 

As a first approximation, the reactions of pyridines with electrophiles can be compared with those of trimethylamine and benzene. Thus, pyridine reacts easily at the nitrogen atom with reagents such as proton acids, Lewis acids, metal ions, and reactive halides to form salts, coordination compounds, complexes, and quaternary salts, respectively. Under much more vigorous conditions it reacts at ring carbons to form C-substitution products in nitration, sulfonation, and halogenation reactions. 

Pseudorotaxanes represent a particular class of complexes—a term first used to describe Werner-type [75] metal complexes, also called coordination compounds. Complexes formed by organic molecules began to attract the attention of chemists around 1950, Mulliken in particular, in a landmark series of papers [76], formulated a theoretical treatment to explain the bonding characteristics and spectral properties of organic complexes based on charge-transfer interactions. During the past 20... 

Coordination number is more than just a convenient method of classifying coordination compounds—complexes of a given transition metal ion with the same coordination number often also have closely related magnetic properties and electronic spectra. In later chapters of this book, these... 

Qualitative anticorrosive, decorative, abrasion-resistant, and heat-resistant coatings are usually obtained by the electrolysis of solutions containing coordination compounds (complexes) of metals. Electrochemical processes involving these compounds are rather complicated because they proceed through several different stages, such as the mass transfer of chemically interacting particles, adsorption, charge transfer, formation of new phases, and so on. 

Cu(NH3)4], was recorded upon contact between brass alloy and ammonium chloride. Addition of Prussian blue Fe4[Fe(CN)6]3-xH20 increased the use of coordination compounds in dyes and pigpients. A platinum complex K2[PtCl6] offered an application for the refinement of platinum metal. Thus, before the coordination chemistry was structured, the coordination compounds, complexes and chelates found their apphcations. 

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