Inorganic substituents

Some microbial exopolysaccharides contain the inorganic substituents phosphate and sulphate. Phosphate has been found in exopolysaccharide from bacteria of medical importance, including Escherichia coli. Sulphate is far less common than phosphate and has only been found in spedes of cyanobaderia. In addition to these inorganic components, which form part of the structure of some exopolysaccharides, all polyanionic polymers will bind a mixture of cations. Exopolysaccharides are, therefore, purified in the salt form. The strength of binding of the various cations depend on the exopolysaccharide some bind the divalent cations calrium, barium and strontium very strongly, whereas others prefer certain monovalent cations, eg Na ... 

Both the electrochemical character of the element (p. 6) and its behaviour as an inorganic substituent (ut supra) seem to indicate the desirability of including it in Group I-, the arrangement adopted in... 

The modern practice of symbolizing substitution by placing the respective designations before the otherwise unaltered name of the parent compound grew from this approach. The field for substitution names widened beyond limits when, with the inauguration of structural chemistry and the aromatic theory, a detailed picture of the chemical formula became available and hydrocarbon radicals now competed with inorganic substituents in producing an unforeseen multiplicity of names. 

Substituent groups (or substituents), considered as replacing hydrogen atoms in parent hydrides, are named using appropriate suffixes ( ol , thiol , peroxol , carboxylic acid , etc.) and prefixes ( hydroxy , phosphanyl , bromo , nitro , etc.). Substituent suffixes are ranked in Section P-43 of Ref. 1. Prefixes are extensively listed in Appendix 2 of Ref. 1. The case of substituents formed by removal of one or more hydrogen atoms from a parent hydride is explained briefly, with examples, in Section IR-6.4.7, and prefixes for many common inorganic substituents are included in Table IX. 

Ab initio and DFT calculations have been made for vibrational wavenumbers of CH3Si(C=CH)3.83 Assignments and intensity measurements have been made for vC=C modes for Me3MC=CX, where M = Si, Ge or Sn, X = organic and inorganic substituents.84... 

Selective and Stepwise Synthesis of Cyclosiloxanes with Mixed and "Inorganic" Substituents... 

Compared with organic-substituted cyclosilazanes only a few Si-N ring systems with inorganic substituents are known. We succeeded in the synthesis of (Cl2SiN-) and the first (F2SiN-) cyclodi-and cyclotrisilazanes [1-3]. 

The most intensively studied catalysts for the promotion of dehydrogenative Si-Si-bond formation are metallocene derivatives of group IV metals first reported by Harrod and co-workers [53], Their general structure can be described as CP2MR2 (Cp = cyclopentadienyl derivative M = metal centre R = organic or inorganic substituent). 

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