The Analysis of Organosilicon Compounds

A63. A. P. Kreshkov et al., Analiz kremniiorganicheskikh soedinenii. Goskhimizdat, Moscow, 1954. 255 pp. On the analysis of organosilicon compounds. 

The anomalous response of the flame ionisation detector in the analysis of organosilicon compounds has been investigated454,455. The behaviour of the compounds was studied on columns of silicone elastomer on Chromosorb or Celite. Above a critical sample size, the top of the peak became inverted, the maximum height remaining the same, but the depth of the inverted portion increased with increasing sample size. 

The Analysis of Organosilicon Compounds, Midland Silicones Ltd., Publication A3-2 7 PP (February 1957). 

This monograph is divided into six chapters. The silicon-carbon bond (Chapter 1) and the basic compounds of organic silicon (Chapter 2) are discussed first. Chapter 3 treats the preparation and the properties of individual compounds in all organosilicon classes. The applications of organic silicon in industry, synthesis and medicine are discussed in Chapter 4. Chapter 5 describes the analysis of organosilicon compounds and Chapter 6 presents the topical bibliography. 

Si shielding tensor information may reflect the structure of organosilicon compounds while the structure might have been determined by X-ray crystallographic analysis. Thus,... 

The ultimate analysis of organosilicon compounds is an important subject to every worker in the field of siloxane polymers and their intermediates, for without dependable analytical methods the research chemist gropes blindly, at a loss concerning the composition of his products and unable to evaluate the effects of chemical attack. It is the purpose Of this chapter to trace very briefly the development of adequate analytical procedures for organosilicon compounds, with particular emphasis upon those methods which may be used for investigating the composition of silicone polymers. 

Spectrographic analysis of organosilicon compounds has been carried out36 by the use of the emission lines at 634.7 and 637.1 nm. The sample is decomposed in acid solution by a spark discharge between platinum electrodes. 

Further details on the assignment of frequencies to particular structural features of organosilicon compounds are given below. These are useful for the general characterization of organosilicon compounds. This is followed by some examples of the application of infrared spectroscopy to the quantitative analysis of organosilicon compounds. 

Reports have appeared on environmental aspects of the silicones general influence in the environment, influence in aquatic environments, and in soils. A comprehensive review has appeared of the gas-chromatographic analysis of organosilicon compounds, and the determination of (PDMS) in fats and oils. ... 

Other methods that have found use in measurement of T relaxation of organosilicon compounds are FIRFT (Fast Inversion Recovery combined with Fourier Transform)344,349-352 and saturation recovery353. Each of these sequences produces some dependence of the signal on a time parameter. In order to get the relaxation time, the dependence must be analysed often, a non-linear three-parameter analysis is used354. 

In spite of the known phases, the advantage of suggested selective immovable phase is the possibility of selective analysis of various classes of organic and organosilicon compounds. Of spe-cial attention should be peculiarity of the phase to separation of cyclic and naphthene hydrocarbons, amines and alcohols with preservation of high thermal stability. 

The synthesis and the structural analysis of silicon unsaturated compounds impressively demonstrate that tricoordinate silicon species are able to exist under normal conditions. Since more than 50 years organosilicon research tries to answer the question if this might be true for silyl cations RsSi, in which silicon also is surrounded by three neighbors. Those compounds seem to meet the requirements because silicon is more electropositive than the carbon homologue and therefore should accommodate a positive charge more efficiently. And in fact, calculations confirm that [HsSi] is thermodynamically much more stable than [HsC]. ... 

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