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Download Nomenclature of coordination compounds: IUPAC rules. Isomerism
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Isomerism: Constitutional isomers, Stereoisomers. D-Najlaa alradadi 1 • Isomers Structural isomer: same composition, but different atom connectivity Stereo isomer: same atom connectivity, but Spatial arrangement of different atoms D-Najlaa alradadi 2 Molecules that have the same chemical composition but differ in structural composition is called isomers and called this property isomerism D-Najlaa alradadi 3 Items appear transitional property isomerism very clearly so we will talk about the different types of isomerism D-Najlaa alradadi 4 isomerism spatial Position Geometric Isomerism Ionization Isomerism Hydrate Isomerism Optical Isomerism Linkage Isomerism Monomer Isomerism Coordination Isomerism Coordination Position Isomerism Ligand Isomerism D-Najlaa alradadi 5 * Isomerism water and Isomerism ion in the cationic complexes. * Isomerism Linkage -communicationin ionic and cationic complexes. * Isomerism monomer in the netural complexes. D-Najlaa alradadi 6 1) Position ( ) Isomerism : 1-1)Ionization Isomerism : This type of isomerism found in the case of anion exchange between the metal ion is associated in the area of consistency with the anion in the domain outside of the overlay. Example : ]Cr(NH3)5SO4[Br ‚ ]Cr(NH3)5Br[ SO4 ]Cr(NH3)5SO4[Br + AgNO3 ]Cr(NH3)5Br[SO4 + Ba(NO3)2 ]Cr(NH3)5SO4[+ + AgBr ]Cr(NH3)5Br[2+ + BaSO4 D-Najlaa alradadi 7 For example: pentaaminebromidocobalt(III)sulphate [Co(NH3)5Br]SO4 is red violet and in solution gives a precipitate with barium chloride, confirming the presence of sulphate ion, while pentaaminesulphatecobalt(III)bromide [Co(NH3)5SO4]Br is red and tests negative for sulphate ion in solution, but instead gives a precipitate of AgBr with silver nitrate. D-Najlaa alradadi 8 In one example the choloride is bound to the cobalt and bromide is the counter ion. In the other coordination isomer the bromide is coordinated to the cobalt and chloride is the counter ion. D-Najlaa alradadi 9 1-2)Hydrate Isomerism : In complexes where there are a number of water molecules may have more than one similar because the water molecule can exist in the coordination field or found in the crystal lattice, for example, when we pass hydrogen chloride in a solution of chrome alum record consists of newly violet compound ]Cr(H2O)6[Cl3 The nomination of this compound and adding ether saturated with hydrogen chloride to the filtrate gives a pale green compound ]Cr(H2O)5Cl[Cl2.H2O D-Najlaa alradadi 10 While if Reduction hexa oxide chromium by acid HCl concentration, and left the solution for a composite consisting ]Cr(H2O)4Cl2[Cl.2H2O Dark green and solutions of these newly prepared Similar complexes with silver nitrate to give all, two-thirds, one third of the existing chloride, respectively. D-Najlaa alradadi 11 For example: [Cr(H2O)6]Cl3 is violet [Cr(H2O)5Cl]Cl2.H2O is blue-green [Cr(H2O)4Cl2]Cl.2H2O is dark green. D-Najlaa alradadi 12 1-3)Linkage Isomerism : There is this kind of isomerism when the coordination group contains the two atoms or more can be consistent with the central atom, such as for example a group (nitrite) can be linked through the nitrogen atom, known as nitro or linked through an oxygen atom known as (nitrito) such as : nitropentaammine Cobalt (III) Chloride (yellow) nitritopentaammine Cobalt (III) Chloride (read) D-Najlaa alradadi 13 Linkage isomers contain the same ligands but one or more of the ligands are coordinated to the metal through a different atoms. These ligands are said to be bidentate. D-Najlaa alradadi 14 In other words, Are compounds that have the same chemical formula but differ in the type of maize related to the central atom (NH4)3]Cr(SCN)6[ )NH4(3]Cr(NCS)6[ D-Najlaa alradadi 15 1-4) Monomer Isomerism : In the case of neutral complexes ]pt(NH3)2Cl2[n=1 ]pt(NH3)4[]ptCl4[n=2 ]pt(NH3)3Cl[]ptCl3(NH3)[ Are compounds with the complications of the values of n and have the same atoms in them. D-Najlaa alradadi 16 1-5) Coordination Isomerism : If the complex on the anions and cations in the same compound, the complex the isomers differ only in the place of harmony between the groups, anions cations. and or other words, is a compounds with the same chemical formula but differ in the quality associated with that is connected to atom central and usually contains two atoms in the center . D-Najlaa alradadi 17 As in the following examples : 3 3 [Co( NH 3 ) 6 ] [Cr (C2O4 )3 ] & [Cr ( NH 3 ) 6 ][Co(C2O4 )3 ] [Cr( NH 3 ) 6 ][Co( NCS ) 6 ] & [Cr( NH 3 ) 4 ( NCS ) 2 ][Co( NH 3 ) 2 ( NCS ) 4 ] [Co( NH3 )6 ][Cr(CN )6 ] & [Co(CN )6 ][Cr ( NH3 )6 ] 3 3 [Cr( NH3 )6 ] [Co(CN )6 ] 3 3 [Co( NH3 )6 ] [Cr(CN )6 ] D-Najlaa alradadi 18 this occurs when both positive and negative ions of a salt are complex ions and the two isomers differ in the distribution of ligands between the cation and anion. Forthe example: [Co(NH3)6][Cr(CN)6] and [Cr(NH3)6][Co(CN)6] D-Najlaa alradadi 19 1-6) Coordination Position Isomerism : Is a complexes have the same chemical formula but differ in the number of ligands that connect to each central atom where the substitution between them. D-Najlaa alradadi 20 Example : D-Najlaa alradadi 21 1-7) Ligand Isomerism : Arises from the presence of the same form inside ligand . [Co(en) 2 (C6 H 4CH 3 NH 2 )]Cl3 Example : D-Najlaa alradadi 22 2-Spatial Isomerism : 2-1)Geometric Isomerism : In this type of isomerism , the coordination groups (ligands) arrange themselves in different places for the atom central If we take, for example, compound (M a2 b2) in the installation (Square planar), this compound have 2 isomers (I), (II) as the following: D-Najlaa alradadi 23 However, if complex the symbol [M abcd] means that the coordination of the four different groups in the same (Square planar), the installation of this compound can be found in three different arrangements which is has three isomers D-Najlaa alradadi 24 Composition of regular quartet (Tetrahedral) of the complexes [M a2b2] or [M abcd] can be found only in a single image and does not have isomers. D-Najlaa alradadi 25 cis-trans isomers occurs in octahedral and square planar complexes (but not tetrahedral). D-Najlaa alradadi 26 Elements that are found in complexes isomers cis - trans is a nickel models, especially with (unsymmetrical glyoximes) as in the following figure: R = CH3 − ‚ R = CH2C6H5 D-Najlaa alradadi 27 Coordination number 5 : Trigonal bipyramidal Square pyramidal D-Najlaa alradadi 28 Gives more pictures engineering at coordination the different groups [MA3B2], and there are three geometric shapes of this complexes is as follows: D-Najlaa alradadi 29 Gives more geometric pictures at different ligands [MA3B2] Axial Diagonal D-Najlaa alradadi 30 As an example of complexes that take installation (regular octahedron) complex the [CoCl2(NH3)4] which has the composition [MX4L2] There is tow isomers cis and trans, as in the following figure: cis-[CoCl2(NH3)4]+ trans-[CoCl2(NH3)4]+ D-Najlaa alradadi 31 (Cr - Cl) a determination that the double polar chlorine electronegativity more of chromium electrons part. and thus pulls How can I differentiate between them? Measurement methods are determined, we find the polar double that if Trans (outcome = zero), while cis (outcome = a specific value). D-Najlaa alradadi 32 complex octahydral of the type [MA3B3] has tow isomers geometric first is called (facial) or abbreviated (fac) and like the second is called (meridional) or abbreviated (mer) in the like first try to list the coordination groups so that for every set (A) group of the other type (B) which is on each of the three axes (x, y, z) tow coordination groups different (a , B) and thus we get the form (a) There are other arrangement is that there are two sets coordination groups of the same type on an axis and not the center of (x) and two sets of the other type on the axis (y). (mer-) (meridional) )b( )fac-( (facial) )a ( D-Najlaa alradadi 33 Does not remain then only be set (A) remaining on the tip of the third axis (z) the coordination group (B) and thus we get the form (b): (mer-) (meridional) )b( )fac-( (facial) )a ( D-Najlaa alradadi 34 Examples of this type of complexes Gelesinat triple chrome )Ш( )fac-( (mer-) D-Najlaa alradadi 35 fac-[CoCl3(NH3)3] mer-[CoCl3(NH3)3] D-Najlaa alradadi 36 2-2)Optical Isomerism : [CoCl2(en)2]+ dichiorobis(ethylenediamine)Cobalt(III) This has complex tow isomers (cis) ,(trans) . )form - cis( Active optical )d - form( )form - trans( Not Active optical )l - form( D-Najlaa alradadi 37 To know is there for them or one similar to light or not? We have to draw a mirror image of each. The next step is to try to put the image of the original shape of the mirror is clear that the Trans-like applies to the mirror image-like while (cis) does not apply to his mirror image. D-Najlaa alradadi 38 If you like Trans have a molecule level of symmetry or center of symmetry in the sense that if you put a mirror perpendicular to the line or association (Cl - Cl), it divides the molecule into two halves, each a mirror of the last words located at the same level of mirror Dividing into halves are identical or if we we dropped a column of the chlorine atom at xy)) then extended the line to be an equal distance to find the same atom of any atom of chlorine in the other side of the level in this case, the molecule ion or similar and then apply the original image on the mirror image . D-Najlaa alradadi 39 Like (cis) therefore not similar if started from the chlorine atom, which on the axis (z) and brought down the column at (xy) and continued the line to a distance equal level of chlorine will not find another. atom the like (cis) rotates the plane of polarized light to the right is called (d, dextro) runs the mirror image plane of polarized light to the left and the so-called (L, levo) D-Najlaa alradadi 40 Like (cis) and his mirror image, called together a double optical (enantiomeric paie) ionic complexes [CoCl2(en)2]+, there has tow geometrical isomers one rotates the plane of polarized light and therefore has a similar light, there is complex of the three isomers. )form - cis( )form - trans( D-Najlaa alradadi 41 The study of ion composition shows that, despite that this ion has no geometric isomers, but it can be found in the two images (a) and (b) as follows because it lacks the level of parity. isomer)a( mirror isomer)b( D-Najlaa alradadi 42 Optical isomerism occurs when a molecule is not superimposable with its mirror image. D-Najlaa alradadi 43 The symbol Λ (lambda): is used as a prefix to describe the lefthanded propeller twist formed by three bidentate ligands, as shown. Likewise, the symbol Δ (delta): is used as a prefix for the right-handed propeller twist. D-Najlaa alradadi 44 Δ-[Fe(ox)3]3− Λ-[Fe(ox)3]3− D-Najlaa alradadi 45 Δ-cis-[CoCl2(en)2]+ Λ-cis-[CoCl2(en)2]+ D-Najlaa alradadi 46 (i) cis-isomers of octahedral complexes with 2 bidentate ligands and 2 monodentate ligands (cis-bis chelates). D-Najlaa alradadi 47 . (ii) octahedral complexes with 3 bidentate ligands (tris chelates) D-Najlaa alradadi 48 1- Optical symmetry is achieved provided that apply to two photos on each other any deviation occurs for light polarized to the right or left . 2- There is no symmetry of the optical image of engineering Trans. If the complex on three ligands bidentate , such as [Co(en)3]3+ in this case resides in the image of overlapping geometric one, but have a similar light. D-Najlaa alradadi 49 * What kind of similarity between each pair of the following compounds? ]COCl(H2O)(en)2[Cl2 and ]ptCL2(NH3)4[ Br2 and ]CO(NH3)5SCN[)NO3(2 and ]COCl2(en)2[Cl.H2O ]ptBr2(NH3)4[Cl2 ]CO(NH3)5NCS[(NO3)2 * Determined using the methods of measuring the polar dual how you can differentiate between the two forms of Cis and Trans complex [Co(en)2Br2]Cl ? * Draw all isomers possible for the following complexes? [Ni(NH3)(H2O)2Br2] [Cr(NH3)4Cl2]+ * What are the different methods used to differentiate between the two forms of Cis and Trans complex [Co(en)2Cl2]+ ? D-Najlaa alradadi 50