Isomers ionization

This type of isomerism occurs when isomers produce different ions in solution, and is possible in compounds which consists of a complex ion with a counter ion which is itself a potential ligand. The pairs [Co(NH3)5(N03)]S04, [Co(NH3)5(S04)]N03 and [PtCl2(NH3)4]Br2, [PtBr2(NH3)4]Cl2, and the series [CoCl(en)2-(N02)]SCN, [CoCl(en)2(SCN)]N02, [Co(en)2-(N02)(SCN)]C1 are examples of ionization isomers. 

Wan, Q.- H., Davies, M. C., Shaw, P. N., and Barrett, D. A., Retention behavior of ionizable isomers in reversed-phase liquid chromatography a comparative study of porous graphitic carbon and octadecyl bonded silica, Anal. Chem., 68, 437, 1996. 

Although the compounds [Pt(en)2Cl2]Br2 and [Pt(en)2Br2]Cl2 have the same empirical formulas, they are quite different compounds. For example, the first gives Br- when dissolved in water, whereas the second gives Cl-. This occurs because in the first case, the Cl- ions are coordinated to the Pt4+, whereas in the second case the Br- ions are coordinated to the metal ion. The isomerism in cases such as these is known as ionization isomerism. It is easy to see that many pairs of compounds could be considered as ionization isomers, among them the following examples ... 

An ionization isomer results from the exchange of ions inside and outside the coordination sphere. 

Ionization isomer chem One of two or more com pounds that have identical molecular formulas but different ionic forms.. T-o-no za shon T-so-mor ... 

The ionization isomers [Co NHj)5Br]S04 and [CofNHj SOJBr dissolve in water to yield different ions and thus react differently to various reagents ... 

Ionization isomers differ by the exchange of a ligand with an anion or neutral molecule outside the coordination sphere. For instance, [CoBr(NH3)5]S04 and [CoS04(NH3)5]Br are ionization isomers because the Br ion is a ligand of the cobalt in the former but an accompanying anion in the latter. The two compounds have different physical properties the bromo complex is violet and the sulfato complex is red. The chemical properties of the two ionization isomers are also different the red isomer forms an off-white precipitate of AgBr when Agf ions are added, but no precipitate forms after the addition of Ba2-1- ... 

Hydrate isomers are a special type of ionization isomer. They differ by an exchange between an HzO molecule and another ligand in the coordination sphere (Fig. 16.24). For example, the solid hexahydrate of chromium(III) chloride, CrCl3-6H20, may be any of the three compounds... 

Isomers that have different connections among their constituent atoms are called constitutional isomers. Of the various types of constitutional isomers, we ll discuss just two linkage isomers and ionization isomers. 

Ionization isomers differ in the anion that is bonded to the metal ion. An example is the pair [Co(NH3)5Br]S04, a violet compound that has a Co-Br bond and a free sulfate anion, and [Co(NH3)5S04]Br, a red compound that has a Co-sulfate bond and a free bromide ion. Ionization isomers get their name because they yield different ions in solution. 

Many complexes exist as isomers, compounds that have the same formula but a different arrangement of the constituent atoms. Constitutional isomers, such as linkage isomers and ionization isomers, have different connections between their constituent atoms. Stereoisomers (diastereoisomers and enantiomers) have the same connections but a different arrangement of the atoms in space. The most common diastereoisomers are cis and trans isomers of square planar MA2B2 and octahe-... 

Draw all possible constitutional isomers of [Ru(NH3)5-(N02)]C1. Label the isomers as linkage isomers or ionization isomers. 

The pair of compounds Co(NH3)5SOtBr and Co(NH3) 6Br s+SO are said to be ionization isomers. The first of these, in which the sulfate ion occupies one of the octahedral positions about the cobalt atom, reacts only slowly with Ba2+ but gives an immediate precipitate with Ag+. The reverse is true of the second compound which contains a Co—Br bond. 

This arises when the counterion in a complex salt is a proligand and can, in principle, displace a ligand which can then become the counterion. An example is provided by the ionization isomers [Co(NH3)5SOJBr and [Co(NH3)5Br](S04). 

Structural (constitutional) isomers (Applied to coordination compounds.) Isomers whose differences involve more than a single coordination sphere or else different donor atoms they include ionization isomers, hydrate isomers, coordination isomers, and linkage isomers. 

Write the formula for a potential ionization isomer of each of the following compounds. Name each one. 

E7.11 [RuBr(NH3)5]Cl and [RuCl(NH3)5]Br complexes differ as to which halogen is bonded, and as to which one is the counter ion. These types of isomers are known as ionization isomers because they give different ions in the solution. When dissolved [RuBr(NH3)5]Cl will dissociate into [RuBr(NH3>5] and chloride ions, while [RuCl(NH3)5]Br will produce [RuClfNHajs] and bromide ions. 

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