Classical coordination compounds

This section is almost entirely concerned with the kinetics of solid phase decompositions of classical coordination compounds, since most of the information available refers to these substances. The hydrates, in which the ligands are water only, are correctly classified under the present heading, but as their dehydrations have been so intensively studied, a separate section (Sect. 1) has been devoted to the removal of water from crystalline hydrates. A separate water elimination step also preceeds many decomposition reactions. 

In summary, it can be concluded that "non-classical coordination compounds" are chemical compounds not explained by the textbooks. As the papers in this ACS symposium series "Inorganic Chemistry Towards the 21st Century" are examined, the reader will find much that is "non-classical" today but will be "classical" by the 21st century. 

Rhodium is normally plated from a sulfate or phosphate bath. It is palladium and platinum that give more scope for some classic coordination compounds. 

Thus, use of ultrasound is very common in chemical processes, first of all in the optimization of syntheses of organic compounds, which are out of the area of the present book. Classic coordination compounds, such as, for example, metal chelates, synthesized by this technique, are not sufficiently represented in the available literature. More attention is paid to US preparation of a- and Ji-organometallic compounds, mainly s- and p-metals (Li, Mg, Al), which frequently serve as precursors for organic synthesis reactions. 

The historical sketch outlines the class of lanthanide amides this article is to deal with and which is further manifested in Scheme 1. Organometallic amides which can be classified as dialkyl (-aryl, -silyl) amides and amides derived from unsaturated heterocyclic ligands are seen with respect to N-unsubstituted (primary, inorganic) amides. The consideration of more classic coordination compounds like acid amides or sulfonamides, often ascribed as wet chemistry , is excluded. The historical data also demonstrate the relatively late start of lanthanide amide chemistry reflecting the late industrial establishment of the lanthanide elements (separation, purification, etc.) [9], However, lanthanide amides are still the youngest class in conjunction with the most important pillars of organometallic lanthanide chemistry, namely the alkyls/cyclopentadienyls (LnCp3, 1954, [10]) and the alkoxides (Ce(OR)4 1956 [11a] La(OR)3 , 1958 [lib]). Indeed most of the work has been conducted in the last ten years. 

The application of organometallic complexes and moieties in life science, in general, or in radiopharmacy, in particular, is very recent. Still, bioorganometal-lic chemistry is progressing very fast since it offers an attractive and challenging topic besides the pathway of using classical coordination compounds. Clearly, novelty is not a sufficient argument to work in a field however,... 

Fig. 2 The basic features of a metal K-edge X-ray absorption spectrum highlighted on the spectra of two classical coordination compounds D4h CuCl42 (pale line) and CuCl42- (dark line). The inset shows the pre-edge region is expanded at the bottom [22]...

Formulae can also be used to indicate two- or three-dimensional structures. This is particularly useful for coordination compounds, which are discussed next. However, this use is not restricted to classical coordination compounds, as the following examples show. Special devices are often adopted to indicate bonds or lines that are not in the plane of the paper. Their use is not consistent throughout chemistry, but the meaning in any given case is generally obvious. 

Compounds of this type conform to the 18-electron rule better than classical coordination compounds. Thus ... 

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