SlideShare a Scribd company logo
1 of 46
Download to read offline
COMPLEXATION
Shaikh Sabina Meraj
Assistant Professor
Y.B. Chavan College of Pharmacy.
1
DEFINITION
 Complex compounds are defined as those
molecules in which most of the bonding
structures can be described by classical
theories of valency between atoms, but one or more
of these bonds are somewhat
anomalous(different).
 A complex is a species formed by the reversible or
irreversible association of two or more interacting
molecules or ions.
 Complexes have been usually referred to as coordination
compounds. 2
INTRODUCTION
 Intermolecular forces involved in the formation of
complexes are
 Coordinate covalence is important in metal complexes.
 Van der Waals forces of dispersion
 Hydrogen bonding: provide a significant force in some
molecular complexes
 Hydrophobic interaction
3
INTRODUCTION
 Once complexation occurs, the physical and chemical
properties of the complexing species are altered
(solubility, stability, partitioning, energy absorption, and
emission and conductance)
 Complex formation usually alters the physical and
chemical properties of the drug. For examples:
(1) chelates of tetracycline with calcium are less water
soluble and are poorly absorbed. 4
INTRODUCTION
(2) Theophylline complexed with ethylenediamine to form
aminophylline is more water soluble and is used for
parenteral and rectal administration.
Theophylline Aminophylline
(Water-soluble)
5
INTRODUCTION
(3) cyclodextrins are used to form complexes with many
drugs to increase their water solubility.
Hydrophilic
exterior
Hydrophobic
interior
Hydrophobic
drug
6
INTRODUCTION:
 Complexes, according to the classic definition, result from a
donor-acceptor mechanism or Lewis acid-base reaction
between two or more different chemical constituents.
 A Lewis acid is a molecule or ion that accepts an electron pair
to form a covalent bond. The acceptor, or constituent that
accepts a share in the pair of electrons, is frequently a metallic
ion, although it can be a neutral ion.
 A Lewis base (Ligand) is a molecule that provides a pair of
unshared electrons by which the base coordinates with the
acid. Any nonmetallic atom or ion, whether free or contained
in a neutral molecule or in an ionic compound, that can donate
an electron pair may serve as the donor. 7
8
CLASSIFICATION OF COMPLEXES
 Complexes may be divided broadly into two classes
depending on whether the acceptor component is a
metallic ion or an organic molecule; these are classified
according to one possible arrangement.
 A third class, the inclusion / occlusion compounds,
involving the entrapment of one compound in the
molecular framework of another.
9
CLASSIFICATION OF COMPLEXES
1. Metal Ion Complexes:
a. Inorganic Type
b. Chelates
c. Mental-olefins
2. Organic molecular Complexes
a. . Drug and caffeine complexes
b. Polymer types
c. Picric acid types
d. Quinhydrone types
3. Inclusion/occlusion Complexes
a. channel lattice type
b. layer type
c. clathrates
d. monomolecular inclusion compounds
10
METAL COMPLEXES
 In this type of coordination complexes, components
are organic molecules and these are held together by
weaker forces or hydrogen bonding.
11
INORGANIC COMPLEXES
 The ammonia molecules in hexamminecobalt (III)
chloride, as the compound [Co(NH3)6] 3+ Cl3 - is
called, as the ligands and are said to be coordinated to
the cobalt ion.
 The coordination number of the cobalt ion, or number of
ammonia groups coordinated to the metal ions, is six.
 Other complex ions belonging to the inorganic group
include [Ag(NH3)2] + , [Fe(CN)6] 4-, and [Cr(H2O)6]
3+ .
 Each ligand donates a pair of electrons to form a
coordinate covalent link between itself and the central
ion having an incomplete electron shell. 12
 For example
13
Ligands such as H2O:, H3N: , NC:-, or Cl:- donate a
pair of electrons in forming a complex with a metal
ion, and the electron pair enters one of the unfilled
orbitals on the metal ion.
14
Hybridization plays an important part in
coordination compounds in which sufficient bonding
orbital's are not ordinarily available in the metal ion.
CHELATES
 When a ligand provides one group for attachment to the
central ion, then its called monodentate.
 Molecules with two or three groups are called bidentate and
tridentate respectively (multidentate or polydentate).
 If a metal ion binds to two or more sites on a multidentate
ligand, a cyclic complex is formed; this cyclic complex is
known as a chelate.
 Chelates are complexes that typically involve a ring-like
structure formed by the interaction between a partial ring of
atom and a metal.
 In chelates, ligands are usually organic molecules, known as
chelating agents, chelators, chelants or sequestering agents. 15
 Some of the bonds in a chelate may be ionic or of the
primary covalent type, while others are coordinate
covalent links.
 The formation of chelate complexes is controlled by
stringent steric requirements on both the metal ion and
the ligand.
16
17
 Many biologically important molecules (e.g.
hemoglobin, insulin, cyanocobalamine, chlorophyll) are
chelates.
 Other biological chelates include albumin, the most
common plasma protein which acts as a carrier of
various metal ions (Cu2+ and Ni2+) and small molecules
in the blood.
 Hemoglobin also contains a porphyrin chelating agent
bonded to an iron II ion.
 In chlorophyll the central ion is magnesium, and the
large organic molecule is a porphyrin. The porphyrin
contains four nitrogen atoms that form bonds to
magnesium in a square planar arrangement.
18
 Ethylenediamine tetraacetic acid (EDTA) has six points
for attachment to the metal ion and accordingly is
hexadentate.
19
 EDTA is a synthetic chelating agent used to sequester
ions (iron and copper) that catalyzes oxidative
degradation reactions in drug preparation.
 EDTA is also widely used to sequester and remove
calcium ions from hard water.
20
 The chelating properties of procainamide (Sodium
channel blocker, Class IA antiarrhythmic) has been used
as an assay for its content in pharmaceutical
preparations.
 Complex formation with Cu2+ results in a colored
compound that can be measured by visible
spectrophotometry.
 Thus calorimetric methods to assay procainamide in
injectable solutions is based on the formation of a 1:1
complex of procainamide with cupric ion at pH 4 to 4.5.
21
22
 Tetracycline antibiotics are capable of acting as chelating
agents and binding a variety of polyvalent metal ions
(Fe2+, Mg2+, Al3+, Bi3+ ).
 The complexation results in changes in both the drugs’
and the metal ions’ physical and chemical properties.
 The complexation between tetracycline antibiotics and
metal ions either in food (cabbage) or in pharmaceutical
preparations (iron containing supplements) has been
found to reduce both the solubility and bioavailability of
the antibiotics.
23
 Tetracyclines are contraindicated in pediatric patients
since they are prone to tetracycline complexation of
calcium in teeth and bones resulting in teeth
discoloration and bone growth problems.
OLEFIN TYPES
 These types of complexes are used as catalysts in the
manufacture of bulk drugs, intermediates and
in the analysis of drugs.
24
ORGANIC MOLECULAR COMPLEX
 In this type of coordination complexes, components
are organic molecules and these are held together by
weaker forces or hydrogen bonding.
 Classification of organic molecular complex
a. Drug and caffeine complexes
b. Polymer types
c. Picric acid types
d. Quinhydrone types
25
ORGANIC MOLECULAR COMPLEX
 Hydrogen bonds - Here dipole-dipole and london type of
forces are responsible for its stability.
 The compounds N-dimethyl aniline and 2,4,6-
trinitroanisole react in the cold to give a molecular
complex:
26
27
 Charge transfer complexes- In this type one molecule
polarize other, resulting in electrostatic interaction
forming a complex with ionic type of interaction.
 Resonance make the main contribution for stability.
 For example, the polar nitro groups of trinitrobenzene
induce a dipole in the readily polarizable benzene
molecule, and the electrostatic interaction that results
leads to complex formation:
28
 Electron donor–acceptor mechanism :- The type of
bonding existing in molecular complexes in which
hydrogen bonding plays no part is not fully understood,
but it may be considered as electron donor–acceptor
mechanism.
A. DRUG AND CAFFEINE COMPLEXES
 Caffeine complexing with a number of acidic drugs, such
as sulfonamide or barbiturate.
 Mechanism: a. dipole–dipole force or hydrogen bonding
between the polarized carbonyl groups of caffeine and
the hydrogen atom of the acid.
b. interaction probably occurs between the
nonpolar parts of the molecules, and the resultant
complex is “squeezed out” of the aqueous phase owing
to the great internal pressure of water.
29
 In caffine molecule Nitrogen becomes more strongly
electrophillic or acid due to withdrawal of oxygen from
both the sides, forming a positive center which is offered
for complexation.
 In benzocaine molecule ester become polarize in such a
way that carboxy oxygen acts as neutrophill or base.
 The complex result in formation of dipole dipole
interaction between carboxy oxygen group of benzocaine
and electrophillic Nitrogen of caffine.
30
 Caffeine forms complexes with organic acid anions that
are more soluble than the pure xanthine, but the
complexes formed with organic acids, such as gentisic
acid, are less soluble than caffeine alone.
 Such insoluble complexes provide caffeine in a form that
masks its normally bitter taste and should serve as a
suitable state for chewable tablets.
31
B. POLYMER TYPES
 Polyethylene glycols, polystyrene, carboxymethylcellulose,
and similar polymers containing nucleophilic oxygens can
form complexes with various drugs., can be attributed to these
interactions. The interactions that may occur in suspensions,
emulsions, ointments and suppositories.
 The incompatibilities of certain polyethers, such as the
Carbowaxes, Pluronics, and Tweens with tannic acid, salicylic
acid, and phenol may be manifested as a
 precipitate,
 flocculate,
 delayed biologic absorption,
 loss of preservative action,
 undesirable physical, chemical, and pharmacologic effects. 32
C. PICRIC ACID TYPES
 Picric acid, being a strong acid, forms organic
molecular complexes with weak bases, whereas it
combines with strong bases (anesthetic activity of
butesin) to yield salts.
 Picric acid complexes – such as Butesin picrate which
combines the antiseptic property of picric acid and
anesthetic property of Butesin used as a 1% ointment for
burns and painful skin abrasions.
33
34
2
Butesin Picric acid
 Quinhydrone complexes – quindrone complex is
formed by mixing alcoholic solutions of benzoquinone
and hydroquinone forming green crystals.
 Quinhydrone, the complex disassociates into equivalent
amounts of quinone and hydroquinone in an Aqueous
Saturated solution.
35
 These complexes are also called occlusion
compounds in which one of the components is
trapped in the open lattice or cage like crystal
structure of the other.
 A class of addition compounds where one of the
constituent of the complex is trapped in the the other to
yield a stable layout.
 Type of Host-Guest compound.
 Depends on the architecture arrangement rather than the
chemical affinity.
36
CHANNEL TYPES
 When the powder (host) crystallizes in the form of
channels, these channels have specific characteristics and
stereochemistry that allows only Specific type of guest
molecule to fit in.
 A very common example of such complexes is the one
formed by starch and iodine where iodine molecules are
trapped within channels consisting of spirals of glucose
residues of starch; other materials capable of forming
these channels include bile acids, urea and theorem.
37
LAYER TYPE
 Compounds such as clays, montomorillorite
(constituent of bentonite), can entrap hydrocarbons,
alcohols and glycols.
 They form alternate monomolecular (monoatomic)
layers of guest and host.
 Their uses are currently quite limited; however these
may be useful for catalysis on account of a larger
surface area.
38
CLATHRATES
39
 The clathrates crystallize in the form of a cage like lattice
in which the coordinating compound is entrapped.
Chemical bonds are not involved in these complexes, and
only the molecular size of the encaged component is of
importance.
 The stability of a clathrate is due to the strength of the
structure, that is, to the high energy that must be
expended to decompose the compound.
 the highly toxic agent hydroquinone (quinol) crystallizes
in a cage like hydrogen-bonded structure.
 The holes have a diameter of 4.2 A and permit the
entrapment of one small molecule to about every two
quinol molecules. Small molecules such as methyl
alcohol, CO2, and HCl may be trapped in these cages,
 But larger molecules such as ethanol cannot be
accommodated.
40
41
Cagelike structure formed through hydrogen bonding of hydroquinone molecules.
Small molecules such as methanol are trapped in the cages to form the clathrate
 In this class of inclusion compounds, a single guest
molecule is entrapped in the cavity of one host molecule.
 A representative example of such compounds is
cyclodextrins.
 Cyclodextrins are cyclic oligosaccharides containing a
minimum of six D (+) glucopyranose units attached by
an -1,4 linkage.
 Cyclodextrins are produced from starch by the action of
bacterial amylase.

42
43
Host molecule
Cavity for guest molecule
Hydrophobic interior
Hydrophilic entrance
 The interior of the CD cavity is usually hydrophobic
because of the CH2 groups, while the exterior of the
cavity is hydrophilic because of the presence of the
hydroxyl groups.
 Complexation with CD does not ordinarily involve the
formation of covalent bonds. Molecules of appropriate
size and stereochemistry can be included in the
cyclodextrin cavity by hydrophobic interaction.
44
 The naturally occurring α-CD, β-CD and γ-CD contain 6,
7 and 8 units of glucose respectively.
 The cyclodextrins form a ring and the molecule actually
exists as a truncated cone in which guest molecules can
be accommodated to form an inclusion complex.
 The size of the cavity increases by increasing the number
of glucose units, α -CD being the smallest, α -CD is not
very useful for pharmaceutical applications, β-CD and
γ-CD are more useful owing to the large cavity.
45
Thank you
46

More Related Content

What's hot

Pharmaceutical Engineering: Evaporation
Pharmaceutical Engineering: EvaporationPharmaceutical Engineering: Evaporation
Pharmaceutical Engineering: EvaporationParag Jain
 
Physical pharmacy i third semester (unit-i) solubility of drug
Physical pharmacy i third semester (unit-i) solubility of drugPhysical pharmacy i third semester (unit-i) solubility of drug
Physical pharmacy i third semester (unit-i) solubility of drugMs. Pooja Bhandare
 
Surface and Interfacial tension [Part-6] ( Solubilization, Detergency, Adsorp...
Surface and Interfacial tension [Part-6]( Solubilization, Detergency, Adsorp...Surface and Interfacial tension [Part-6]( Solubilization, Detergency, Adsorp...
Surface and Interfacial tension [Part-6] ( Solubilization, Detergency, Adsorp...Ms. Pooja Bhandare
 
Ideal solubility parameter (solubility of drug part 2)
Ideal solubility parameter (solubility of drug part 2)Ideal solubility parameter (solubility of drug part 2)
Ideal solubility parameter (solubility of drug part 2)Ms. Pooja Bhandare
 
Distribution law
Distribution lawDistribution law
Distribution lawMUL
 
Physicochemical properties of drug molecules
Physicochemical properties of drug moleculesPhysicochemical properties of drug molecules
Physicochemical properties of drug moleculesMahewash Sana Pathan
 
Stability of emulsion
Stability of emulsionStability of emulsion
Stability of emulsionShikha Thakur
 
State of matter and properties of matter (Part-3) (Eutectic mixture)
State of matter and properties of matter (Part-3) (Eutectic mixture)State of matter and properties of matter (Part-3) (Eutectic mixture)
State of matter and properties of matter (Part-3) (Eutectic mixture)Ms. Pooja Bhandare
 
Surface and Interfacial tension [Part-5] (HLB System, Solubilization )
Surface and Interfacial tension [Part-5](HLB System, Solubilization )Surface and Interfacial tension [Part-5](HLB System, Solubilization )
Surface and Interfacial tension [Part-5] (HLB System, Solubilization ) Ms. Pooja Bhandare
 
Mechanism of solute solvent interaction
Mechanism of solute solvent interactionMechanism of solute solvent interaction
Mechanism of solute solvent interactionVickyLone1
 
Solvation and association (Solubility of drug Part -3)
Solvation and association (Solubility of drug Part -3)Solvation and association (Solubility of drug Part -3)
Solvation and association (Solubility of drug Part -3)Ms. Pooja Bhandare
 
Complexation and protein binding
Complexation and protein bindingComplexation and protein binding
Complexation and protein bindingPunitMadaan
 
Solubility-----(Pharmaceutics)
Solubility-----(Pharmaceutics)Solubility-----(Pharmaceutics)
Solubility-----(Pharmaceutics)Soft-Learners
 
Surface and Interfacial tension [Part-3(b)] (Measurement of Surface and Inter...
Surface and Interfacial tension [Part-3(b)](Measurement of Surface and Inter...Surface and Interfacial tension [Part-3(b)](Measurement of Surface and Inter...
Surface and Interfacial tension [Part-3(b)] (Measurement of Surface and Inter...Ms. Pooja Bhandare
 

What's hot (20)

Liquid complexes
Liquid complexesLiquid complexes
Liquid complexes
 
Pharmaceutical Engineering: Evaporation
Pharmaceutical Engineering: EvaporationPharmaceutical Engineering: Evaporation
Pharmaceutical Engineering: Evaporation
 
Physical pharmacy i third semester (unit-i) solubility of drug
Physical pharmacy i third semester (unit-i) solubility of drugPhysical pharmacy i third semester (unit-i) solubility of drug
Physical pharmacy i third semester (unit-i) solubility of drug
 
Surface and Interfacial tension [Part-6] ( Solubilization, Detergency, Adsorp...
Surface and Interfacial tension [Part-6]( Solubilization, Detergency, Adsorp...Surface and Interfacial tension [Part-6]( Solubilization, Detergency, Adsorp...
Surface and Interfacial tension [Part-6] ( Solubilization, Detergency, Adsorp...
 
Complexation and protein binding
Complexation and protein bindingComplexation and protein binding
Complexation and protein binding
 
Solubility of drugs
Solubility of drugsSolubility of drugs
Solubility of drugs
 
Ideal solubility parameter (solubility of drug part 2)
Ideal solubility parameter (solubility of drug part 2)Ideal solubility parameter (solubility of drug part 2)
Ideal solubility parameter (solubility of drug part 2)
 
Distribution law
Distribution lawDistribution law
Distribution law
 
Complexation
ComplexationComplexation
Complexation
 
Physicochemical properties of drug molecules
Physicochemical properties of drug moleculesPhysicochemical properties of drug molecules
Physicochemical properties of drug molecules
 
Stability of emulsion
Stability of emulsionStability of emulsion
Stability of emulsion
 
Solubility of drugs
Solubility of drugsSolubility of drugs
Solubility of drugs
 
State of matter and properties of matter (Part-3) (Eutectic mixture)
State of matter and properties of matter (Part-3) (Eutectic mixture)State of matter and properties of matter (Part-3) (Eutectic mixture)
State of matter and properties of matter (Part-3) (Eutectic mixture)
 
Surface and Interfacial tension [Part-5] (HLB System, Solubilization )
Surface and Interfacial tension [Part-5](HLB System, Solubilization )Surface and Interfacial tension [Part-5](HLB System, Solubilization )
Surface and Interfacial tension [Part-5] (HLB System, Solubilization )
 
Mechanism of solute solvent interaction
Mechanism of solute solvent interactionMechanism of solute solvent interaction
Mechanism of solute solvent interaction
 
Solvation and association (Solubility of drug Part -3)
Solvation and association (Solubility of drug Part -3)Solvation and association (Solubility of drug Part -3)
Solvation and association (Solubility of drug Part -3)
 
Complexation and protein binding
Complexation and protein bindingComplexation and protein binding
Complexation and protein binding
 
Solubility-----(Pharmaceutics)
Solubility-----(Pharmaceutics)Solubility-----(Pharmaceutics)
Solubility-----(Pharmaceutics)
 
Ph, buffers & isotonic solution
Ph, buffers & isotonic solutionPh, buffers & isotonic solution
Ph, buffers & isotonic solution
 
Surface and Interfacial tension [Part-3(b)] (Measurement of Surface and Inter...
Surface and Interfacial tension [Part-3(b)](Measurement of Surface and Inter...Surface and Interfacial tension [Part-3(b)](Measurement of Surface and Inter...
Surface and Interfacial tension [Part-3(b)] (Measurement of Surface and Inter...
 

Similar to Complex

COMPLEXATION & PROTEIN BINDING.pptx
COMPLEXATION & PROTEIN BINDING.pptxCOMPLEXATION & PROTEIN BINDING.pptx
COMPLEXATION & PROTEIN BINDING.pptxBALASUNDARESAN M
 
Complexation and Protein Binding
Complexation and Protein BindingComplexation and Protein Binding
Complexation and Protein BindingVastaviGore
 
Cordination compound, Manik
Cordination compound, ManikCordination compound, Manik
Cordination compound, ManikImran Nur Manik
 
Biocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/Thiols
Biocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/ThiolsBiocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/Thiols
Biocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/ThiolsTope A
 
Chapter 17 complexation and precipitation reactions and titrations
Chapter 17 complexation and precipitation reactions and titrationsChapter 17 complexation and precipitation reactions and titrations
Chapter 17 complexation and precipitation reactions and titrationsCleophas Rwemera
 
CLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptx
CLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptxCLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptx
CLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptxAkankshaAshtankar
 
vitamins and coordination complexes
vitamins and coordination complexesvitamins and coordination complexes
vitamins and coordination complexeskashafrafi
 
Chemical bond and importance in biology akv
Chemical bond and importance in biology akvChemical bond and importance in biology akv
Chemical bond and importance in biology akvakhileshverma07
 
Lecture - 20 Complexometric Titrations.pptx
Lecture - 20 Complexometric Titrations.pptxLecture - 20 Complexometric Titrations.pptx
Lecture - 20 Complexometric Titrations.pptxDRx Chaudhary
 
CHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptx
CHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptxCHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptx
CHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptxShanayaMlanch
 
Class 4 - Summary notes.pdf
Class 4 - Summary notes.pdfClass 4 - Summary notes.pdf
Class 4 - Summary notes.pdfeuphemism22
 
Chemistry of Coordination Compounds.pptx
Chemistry of Coordination Compounds.pptxChemistry of Coordination Compounds.pptx
Chemistry of Coordination Compounds.pptxPackia Nathan
 
Ch2 Ppt Lect 1
Ch2 Ppt Lect 1Ch2 Ppt Lect 1
Ch2 Ppt Lect 1bholmes
 
2. Chemical Basis for Life
2. Chemical Basis for Life2. Chemical Basis for Life
2. Chemical Basis for LifeSUNY Ulster
 

Similar to Complex (20)

COMPLEXATION & PROTEIN BINDING.pptx
COMPLEXATION & PROTEIN BINDING.pptxCOMPLEXATION & PROTEIN BINDING.pptx
COMPLEXATION & PROTEIN BINDING.pptx
 
Complexation 2
Complexation 2Complexation 2
Complexation 2
 
Complexation and Protein Binding
Complexation and Protein BindingComplexation and Protein Binding
Complexation and Protein Binding
 
Cordination compound, Manik
Cordination compound, ManikCordination compound, Manik
Cordination compound, Manik
 
Biocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/Thiols
Biocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/ThiolsBiocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/Thiols
Biocidal Evaluation of Mixed Ligand Metal Complexes of Mercaptans/Thiols
 
Chapter 17 complexation and precipitation reactions and titrations
Chapter 17 complexation and precipitation reactions and titrationsChapter 17 complexation and precipitation reactions and titrations
Chapter 17 complexation and precipitation reactions and titrations
 
CLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptx
CLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptxCLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptx
CLASSIFICATION OF COMPLEXES & ITS APPLICATIONS IN PHARMACY.pptx
 
Coordination compound
Coordination compoundCoordination compound
Coordination compound
 
13-miller-chap-2-lecture.ppt
13-miller-chap-2-lecture.ppt13-miller-chap-2-lecture.ppt
13-miller-chap-2-lecture.ppt
 
vitamins and coordination complexes
vitamins and coordination complexesvitamins and coordination complexes
vitamins and coordination complexes
 
Chemical bond and importance in biology akv
Chemical bond and importance in biology akvChemical bond and importance in biology akv
Chemical bond and importance in biology akv
 
COMPLEXATION AND PROTEIN BINDING
COMPLEXATION AND PROTEIN BINDINGCOMPLEXATION AND PROTEIN BINDING
COMPLEXATION AND PROTEIN BINDING
 
Lecture - 20 Complexometric Titrations.pptx
Lecture - 20 Complexometric Titrations.pptxLecture - 20 Complexometric Titrations.pptx
Lecture - 20 Complexometric Titrations.pptx
 
CHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptx
CHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptxCHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptx
CHAPTER- CO-ORDINATION COMPOUNDS PPT - Copy.pptx
 
Class 4 - Summary notes.pdf
Class 4 - Summary notes.pdfClass 4 - Summary notes.pdf
Class 4 - Summary notes.pdf
 
Chemistry of Coordination Compounds.pptx
Chemistry of Coordination Compounds.pptxChemistry of Coordination Compounds.pptx
Chemistry of Coordination Compounds.pptx
 
Unit IV PP-I PPT.ppt
Unit IV PP-I PPT.pptUnit IV PP-I PPT.ppt
Unit IV PP-I PPT.ppt
 
Ch2 Ppt Lect 1
Ch2 Ppt Lect 1Ch2 Ppt Lect 1
Ch2 Ppt Lect 1
 
Ch2 Ppt Lect 1
Ch2 Ppt Lect 1Ch2 Ppt Lect 1
Ch2 Ppt Lect 1
 
2. Chemical Basis for Life
2. Chemical Basis for Life2. Chemical Basis for Life
2. Chemical Basis for Life
 

Recently uploaded

Call Girls in Dwarka Mor Delhi Contact Us 9654467111
Call Girls in Dwarka Mor Delhi Contact Us 9654467111Call Girls in Dwarka Mor Delhi Contact Us 9654467111
Call Girls in Dwarka Mor Delhi Contact Us 9654467111Sapana Sha
 
Alper Gobel In Media Res Media Component
Alper Gobel In Media Res Media ComponentAlper Gobel In Media Res Media Component
Alper Gobel In Media Res Media ComponentInMediaRes1
 
Micromeritics - Fundamental and Derived Properties of Powders
Micromeritics - Fundamental and Derived Properties of PowdersMicromeritics - Fundamental and Derived Properties of Powders
Micromeritics - Fundamental and Derived Properties of PowdersChitralekhaTherkar
 
Hybridoma Technology ( Production , Purification , and Application )
Hybridoma Technology  ( Production , Purification , and Application  ) Hybridoma Technology  ( Production , Purification , and Application  )
Hybridoma Technology ( Production , Purification , and Application ) Sakshi Ghasle
 
mini mental status format.docx
mini    mental       status     format.docxmini    mental       status     format.docx
mini mental status format.docxPoojaSen20
 
Separation of Lanthanides/ Lanthanides and Actinides
Separation of Lanthanides/ Lanthanides and ActinidesSeparation of Lanthanides/ Lanthanides and Actinides
Separation of Lanthanides/ Lanthanides and ActinidesFatimaKhan178732
 
Crayon Activity Handout For the Crayon A
Crayon Activity Handout For the Crayon ACrayon Activity Handout For the Crayon A
Crayon Activity Handout For the Crayon AUnboundStockton
 
Introduction to ArtificiaI Intelligence in Higher Education
Introduction to ArtificiaI Intelligence in Higher EducationIntroduction to ArtificiaI Intelligence in Higher Education
Introduction to ArtificiaI Intelligence in Higher Educationpboyjonauth
 
Arihant handbook biology for class 11 .pdf
Arihant handbook biology for class 11 .pdfArihant handbook biology for class 11 .pdf
Arihant handbook biology for class 11 .pdfchloefrazer622
 
Presiding Officer Training module 2024 lok sabha elections
Presiding Officer Training module 2024 lok sabha electionsPresiding Officer Training module 2024 lok sabha elections
Presiding Officer Training module 2024 lok sabha electionsanshu789521
 
PSYCHIATRIC History collection FORMAT.pptx
PSYCHIATRIC   History collection FORMAT.pptxPSYCHIATRIC   History collection FORMAT.pptx
PSYCHIATRIC History collection FORMAT.pptxPoojaSen20
 
Paris 2024 Olympic Geographies - an activity
Paris 2024 Olympic Geographies - an activityParis 2024 Olympic Geographies - an activity
Paris 2024 Olympic Geographies - an activityGeoBlogs
 
A Critique of the Proposed National Education Policy Reform
A Critique of the Proposed National Education Policy ReformA Critique of the Proposed National Education Policy Reform
A Critique of the Proposed National Education Policy ReformChameera Dedduwage
 
Concept of Vouching. B.Com(Hons) /B.Compdf
Concept of Vouching. B.Com(Hons) /B.CompdfConcept of Vouching. B.Com(Hons) /B.Compdf
Concept of Vouching. B.Com(Hons) /B.CompdfUmakantAnnand
 
Grant Readiness 101 TechSoup and Remy Consulting
Grant Readiness 101 TechSoup and Remy ConsultingGrant Readiness 101 TechSoup and Remy Consulting
Grant Readiness 101 TechSoup and Remy ConsultingTechSoup
 
Q4-W6-Restating Informational Text Grade 3
Q4-W6-Restating Informational Text Grade 3Q4-W6-Restating Informational Text Grade 3
Q4-W6-Restating Informational Text Grade 3JemimahLaneBuaron
 
_Math 4-Q4 Week 5.pptx Steps in Collecting Data
_Math 4-Q4 Week 5.pptx Steps in Collecting Data_Math 4-Q4 Week 5.pptx Steps in Collecting Data
_Math 4-Q4 Week 5.pptx Steps in Collecting DataJhengPantaleon
 
BASLIQ CURRENT LOOKBOOK LOOKBOOK(1) (1).pdf
BASLIQ CURRENT LOOKBOOK  LOOKBOOK(1) (1).pdfBASLIQ CURRENT LOOKBOOK  LOOKBOOK(1) (1).pdf
BASLIQ CURRENT LOOKBOOK LOOKBOOK(1) (1).pdfSoniaTolstoy
 
Organic Name Reactions for the students and aspirants of Chemistry12th.pptx
Organic Name Reactions  for the students and aspirants of Chemistry12th.pptxOrganic Name Reactions  for the students and aspirants of Chemistry12th.pptx
Organic Name Reactions for the students and aspirants of Chemistry12th.pptxVS Mahajan Coaching Centre
 

Recently uploaded (20)

Call Girls in Dwarka Mor Delhi Contact Us 9654467111
Call Girls in Dwarka Mor Delhi Contact Us 9654467111Call Girls in Dwarka Mor Delhi Contact Us 9654467111
Call Girls in Dwarka Mor Delhi Contact Us 9654467111
 
Alper Gobel In Media Res Media Component
Alper Gobel In Media Res Media ComponentAlper Gobel In Media Res Media Component
Alper Gobel In Media Res Media Component
 
Micromeritics - Fundamental and Derived Properties of Powders
Micromeritics - Fundamental and Derived Properties of PowdersMicromeritics - Fundamental and Derived Properties of Powders
Micromeritics - Fundamental and Derived Properties of Powders
 
Hybridoma Technology ( Production , Purification , and Application )
Hybridoma Technology  ( Production , Purification , and Application  ) Hybridoma Technology  ( Production , Purification , and Application  )
Hybridoma Technology ( Production , Purification , and Application )
 
mini mental status format.docx
mini    mental       status     format.docxmini    mental       status     format.docx
mini mental status format.docx
 
Separation of Lanthanides/ Lanthanides and Actinides
Separation of Lanthanides/ Lanthanides and ActinidesSeparation of Lanthanides/ Lanthanides and Actinides
Separation of Lanthanides/ Lanthanides and Actinides
 
Model Call Girl in Tilak Nagar Delhi reach out to us at 🔝9953056974🔝
Model Call Girl in Tilak Nagar Delhi reach out to us at 🔝9953056974🔝Model Call Girl in Tilak Nagar Delhi reach out to us at 🔝9953056974🔝
Model Call Girl in Tilak Nagar Delhi reach out to us at 🔝9953056974🔝
 
Crayon Activity Handout For the Crayon A
Crayon Activity Handout For the Crayon ACrayon Activity Handout For the Crayon A
Crayon Activity Handout For the Crayon A
 
Introduction to ArtificiaI Intelligence in Higher Education
Introduction to ArtificiaI Intelligence in Higher EducationIntroduction to ArtificiaI Intelligence in Higher Education
Introduction to ArtificiaI Intelligence in Higher Education
 
Arihant handbook biology for class 11 .pdf
Arihant handbook biology for class 11 .pdfArihant handbook biology for class 11 .pdf
Arihant handbook biology for class 11 .pdf
 
Presiding Officer Training module 2024 lok sabha elections
Presiding Officer Training module 2024 lok sabha electionsPresiding Officer Training module 2024 lok sabha elections
Presiding Officer Training module 2024 lok sabha elections
 
PSYCHIATRIC History collection FORMAT.pptx
PSYCHIATRIC   History collection FORMAT.pptxPSYCHIATRIC   History collection FORMAT.pptx
PSYCHIATRIC History collection FORMAT.pptx
 
Paris 2024 Olympic Geographies - an activity
Paris 2024 Olympic Geographies - an activityParis 2024 Olympic Geographies - an activity
Paris 2024 Olympic Geographies - an activity
 
A Critique of the Proposed National Education Policy Reform
A Critique of the Proposed National Education Policy ReformA Critique of the Proposed National Education Policy Reform
A Critique of the Proposed National Education Policy Reform
 
Concept of Vouching. B.Com(Hons) /B.Compdf
Concept of Vouching. B.Com(Hons) /B.CompdfConcept of Vouching. B.Com(Hons) /B.Compdf
Concept of Vouching. B.Com(Hons) /B.Compdf
 
Grant Readiness 101 TechSoup and Remy Consulting
Grant Readiness 101 TechSoup and Remy ConsultingGrant Readiness 101 TechSoup and Remy Consulting
Grant Readiness 101 TechSoup and Remy Consulting
 
Q4-W6-Restating Informational Text Grade 3
Q4-W6-Restating Informational Text Grade 3Q4-W6-Restating Informational Text Grade 3
Q4-W6-Restating Informational Text Grade 3
 
_Math 4-Q4 Week 5.pptx Steps in Collecting Data
_Math 4-Q4 Week 5.pptx Steps in Collecting Data_Math 4-Q4 Week 5.pptx Steps in Collecting Data
_Math 4-Q4 Week 5.pptx Steps in Collecting Data
 
BASLIQ CURRENT LOOKBOOK LOOKBOOK(1) (1).pdf
BASLIQ CURRENT LOOKBOOK  LOOKBOOK(1) (1).pdfBASLIQ CURRENT LOOKBOOK  LOOKBOOK(1) (1).pdf
BASLIQ CURRENT LOOKBOOK LOOKBOOK(1) (1).pdf
 
Organic Name Reactions for the students and aspirants of Chemistry12th.pptx
Organic Name Reactions  for the students and aspirants of Chemistry12th.pptxOrganic Name Reactions  for the students and aspirants of Chemistry12th.pptx
Organic Name Reactions for the students and aspirants of Chemistry12th.pptx
 

Complex

  • 1. COMPLEXATION Shaikh Sabina Meraj Assistant Professor Y.B. Chavan College of Pharmacy. 1
  • 2. DEFINITION  Complex compounds are defined as those molecules in which most of the bonding structures can be described by classical theories of valency between atoms, but one or more of these bonds are somewhat anomalous(different).  A complex is a species formed by the reversible or irreversible association of two or more interacting molecules or ions.  Complexes have been usually referred to as coordination compounds. 2
  • 3. INTRODUCTION  Intermolecular forces involved in the formation of complexes are  Coordinate covalence is important in metal complexes.  Van der Waals forces of dispersion  Hydrogen bonding: provide a significant force in some molecular complexes  Hydrophobic interaction 3
  • 4. INTRODUCTION  Once complexation occurs, the physical and chemical properties of the complexing species are altered (solubility, stability, partitioning, energy absorption, and emission and conductance)  Complex formation usually alters the physical and chemical properties of the drug. For examples: (1) chelates of tetracycline with calcium are less water soluble and are poorly absorbed. 4
  • 5. INTRODUCTION (2) Theophylline complexed with ethylenediamine to form aminophylline is more water soluble and is used for parenteral and rectal administration. Theophylline Aminophylline (Water-soluble) 5
  • 6. INTRODUCTION (3) cyclodextrins are used to form complexes with many drugs to increase their water solubility. Hydrophilic exterior Hydrophobic interior Hydrophobic drug 6
  • 7. INTRODUCTION:  Complexes, according to the classic definition, result from a donor-acceptor mechanism or Lewis acid-base reaction between two or more different chemical constituents.  A Lewis acid is a molecule or ion that accepts an electron pair to form a covalent bond. The acceptor, or constituent that accepts a share in the pair of electrons, is frequently a metallic ion, although it can be a neutral ion.  A Lewis base (Ligand) is a molecule that provides a pair of unshared electrons by which the base coordinates with the acid. Any nonmetallic atom or ion, whether free or contained in a neutral molecule or in an ionic compound, that can donate an electron pair may serve as the donor. 7
  • 8. 8
  • 9. CLASSIFICATION OF COMPLEXES  Complexes may be divided broadly into two classes depending on whether the acceptor component is a metallic ion or an organic molecule; these are classified according to one possible arrangement.  A third class, the inclusion / occlusion compounds, involving the entrapment of one compound in the molecular framework of another. 9
  • 10. CLASSIFICATION OF COMPLEXES 1. Metal Ion Complexes: a. Inorganic Type b. Chelates c. Mental-olefins 2. Organic molecular Complexes a. . Drug and caffeine complexes b. Polymer types c. Picric acid types d. Quinhydrone types 3. Inclusion/occlusion Complexes a. channel lattice type b. layer type c. clathrates d. monomolecular inclusion compounds 10
  • 11. METAL COMPLEXES  In this type of coordination complexes, components are organic molecules and these are held together by weaker forces or hydrogen bonding. 11
  • 12. INORGANIC COMPLEXES  The ammonia molecules in hexamminecobalt (III) chloride, as the compound [Co(NH3)6] 3+ Cl3 - is called, as the ligands and are said to be coordinated to the cobalt ion.  The coordination number of the cobalt ion, or number of ammonia groups coordinated to the metal ions, is six.  Other complex ions belonging to the inorganic group include [Ag(NH3)2] + , [Fe(CN)6] 4-, and [Cr(H2O)6] 3+ .  Each ligand donates a pair of electrons to form a coordinate covalent link between itself and the central ion having an incomplete electron shell. 12
  • 13.  For example 13 Ligands such as H2O:, H3N: , NC:-, or Cl:- donate a pair of electrons in forming a complex with a metal ion, and the electron pair enters one of the unfilled orbitals on the metal ion.
  • 14. 14 Hybridization plays an important part in coordination compounds in which sufficient bonding orbital's are not ordinarily available in the metal ion.
  • 15. CHELATES  When a ligand provides one group for attachment to the central ion, then its called monodentate.  Molecules with two or three groups are called bidentate and tridentate respectively (multidentate or polydentate).  If a metal ion binds to two or more sites on a multidentate ligand, a cyclic complex is formed; this cyclic complex is known as a chelate.  Chelates are complexes that typically involve a ring-like structure formed by the interaction between a partial ring of atom and a metal.  In chelates, ligands are usually organic molecules, known as chelating agents, chelators, chelants or sequestering agents. 15
  • 16.  Some of the bonds in a chelate may be ionic or of the primary covalent type, while others are coordinate covalent links.  The formation of chelate complexes is controlled by stringent steric requirements on both the metal ion and the ligand. 16
  • 17. 17  Many biologically important molecules (e.g. hemoglobin, insulin, cyanocobalamine, chlorophyll) are chelates.  Other biological chelates include albumin, the most common plasma protein which acts as a carrier of various metal ions (Cu2+ and Ni2+) and small molecules in the blood.
  • 18.  Hemoglobin also contains a porphyrin chelating agent bonded to an iron II ion.  In chlorophyll the central ion is magnesium, and the large organic molecule is a porphyrin. The porphyrin contains four nitrogen atoms that form bonds to magnesium in a square planar arrangement. 18
  • 19.  Ethylenediamine tetraacetic acid (EDTA) has six points for attachment to the metal ion and accordingly is hexadentate. 19
  • 20.  EDTA is a synthetic chelating agent used to sequester ions (iron and copper) that catalyzes oxidative degradation reactions in drug preparation.  EDTA is also widely used to sequester and remove calcium ions from hard water. 20
  • 21.  The chelating properties of procainamide (Sodium channel blocker, Class IA antiarrhythmic) has been used as an assay for its content in pharmaceutical preparations.  Complex formation with Cu2+ results in a colored compound that can be measured by visible spectrophotometry.  Thus calorimetric methods to assay procainamide in injectable solutions is based on the formation of a 1:1 complex of procainamide with cupric ion at pH 4 to 4.5. 21
  • 22. 22  Tetracycline antibiotics are capable of acting as chelating agents and binding a variety of polyvalent metal ions (Fe2+, Mg2+, Al3+, Bi3+ ).  The complexation results in changes in both the drugs’ and the metal ions’ physical and chemical properties.  The complexation between tetracycline antibiotics and metal ions either in food (cabbage) or in pharmaceutical preparations (iron containing supplements) has been found to reduce both the solubility and bioavailability of the antibiotics.
  • 23. 23  Tetracyclines are contraindicated in pediatric patients since they are prone to tetracycline complexation of calcium in teeth and bones resulting in teeth discoloration and bone growth problems.
  • 24. OLEFIN TYPES  These types of complexes are used as catalysts in the manufacture of bulk drugs, intermediates and in the analysis of drugs. 24
  • 25. ORGANIC MOLECULAR COMPLEX  In this type of coordination complexes, components are organic molecules and these are held together by weaker forces or hydrogen bonding.  Classification of organic molecular complex a. Drug and caffeine complexes b. Polymer types c. Picric acid types d. Quinhydrone types 25
  • 26. ORGANIC MOLECULAR COMPLEX  Hydrogen bonds - Here dipole-dipole and london type of forces are responsible for its stability.  The compounds N-dimethyl aniline and 2,4,6- trinitroanisole react in the cold to give a molecular complex: 26
  • 27. 27  Charge transfer complexes- In this type one molecule polarize other, resulting in electrostatic interaction forming a complex with ionic type of interaction.  Resonance make the main contribution for stability.  For example, the polar nitro groups of trinitrobenzene induce a dipole in the readily polarizable benzene molecule, and the electrostatic interaction that results leads to complex formation:
  • 28. 28  Electron donor–acceptor mechanism :- The type of bonding existing in molecular complexes in which hydrogen bonding plays no part is not fully understood, but it may be considered as electron donor–acceptor mechanism.
  • 29. A. DRUG AND CAFFEINE COMPLEXES  Caffeine complexing with a number of acidic drugs, such as sulfonamide or barbiturate.  Mechanism: a. dipole–dipole force or hydrogen bonding between the polarized carbonyl groups of caffeine and the hydrogen atom of the acid. b. interaction probably occurs between the nonpolar parts of the molecules, and the resultant complex is “squeezed out” of the aqueous phase owing to the great internal pressure of water. 29
  • 30.  In caffine molecule Nitrogen becomes more strongly electrophillic or acid due to withdrawal of oxygen from both the sides, forming a positive center which is offered for complexation.  In benzocaine molecule ester become polarize in such a way that carboxy oxygen acts as neutrophill or base.  The complex result in formation of dipole dipole interaction between carboxy oxygen group of benzocaine and electrophillic Nitrogen of caffine. 30
  • 31.  Caffeine forms complexes with organic acid anions that are more soluble than the pure xanthine, but the complexes formed with organic acids, such as gentisic acid, are less soluble than caffeine alone.  Such insoluble complexes provide caffeine in a form that masks its normally bitter taste and should serve as a suitable state for chewable tablets. 31
  • 32. B. POLYMER TYPES  Polyethylene glycols, polystyrene, carboxymethylcellulose, and similar polymers containing nucleophilic oxygens can form complexes with various drugs., can be attributed to these interactions. The interactions that may occur in suspensions, emulsions, ointments and suppositories.  The incompatibilities of certain polyethers, such as the Carbowaxes, Pluronics, and Tweens with tannic acid, salicylic acid, and phenol may be manifested as a  precipitate,  flocculate,  delayed biologic absorption,  loss of preservative action,  undesirable physical, chemical, and pharmacologic effects. 32
  • 33. C. PICRIC ACID TYPES  Picric acid, being a strong acid, forms organic molecular complexes with weak bases, whereas it combines with strong bases (anesthetic activity of butesin) to yield salts.  Picric acid complexes – such as Butesin picrate which combines the antiseptic property of picric acid and anesthetic property of Butesin used as a 1% ointment for burns and painful skin abrasions. 33
  • 35.  Quinhydrone complexes – quindrone complex is formed by mixing alcoholic solutions of benzoquinone and hydroquinone forming green crystals.  Quinhydrone, the complex disassociates into equivalent amounts of quinone and hydroquinone in an Aqueous Saturated solution. 35
  • 36.  These complexes are also called occlusion compounds in which one of the components is trapped in the open lattice or cage like crystal structure of the other.  A class of addition compounds where one of the constituent of the complex is trapped in the the other to yield a stable layout.  Type of Host-Guest compound.  Depends on the architecture arrangement rather than the chemical affinity. 36
  • 37. CHANNEL TYPES  When the powder (host) crystallizes in the form of channels, these channels have specific characteristics and stereochemistry that allows only Specific type of guest molecule to fit in.  A very common example of such complexes is the one formed by starch and iodine where iodine molecules are trapped within channels consisting of spirals of glucose residues of starch; other materials capable of forming these channels include bile acids, urea and theorem. 37
  • 38. LAYER TYPE  Compounds such as clays, montomorillorite (constituent of bentonite), can entrap hydrocarbons, alcohols and glycols.  They form alternate monomolecular (monoatomic) layers of guest and host.  Their uses are currently quite limited; however these may be useful for catalysis on account of a larger surface area. 38
  • 39. CLATHRATES 39  The clathrates crystallize in the form of a cage like lattice in which the coordinating compound is entrapped. Chemical bonds are not involved in these complexes, and only the molecular size of the encaged component is of importance.  The stability of a clathrate is due to the strength of the structure, that is, to the high energy that must be expended to decompose the compound.
  • 40.  the highly toxic agent hydroquinone (quinol) crystallizes in a cage like hydrogen-bonded structure.  The holes have a diameter of 4.2 A and permit the entrapment of one small molecule to about every two quinol molecules. Small molecules such as methyl alcohol, CO2, and HCl may be trapped in these cages,  But larger molecules such as ethanol cannot be accommodated. 40
  • 41. 41 Cagelike structure formed through hydrogen bonding of hydroquinone molecules. Small molecules such as methanol are trapped in the cages to form the clathrate
  • 42.  In this class of inclusion compounds, a single guest molecule is entrapped in the cavity of one host molecule.  A representative example of such compounds is cyclodextrins.  Cyclodextrins are cyclic oligosaccharides containing a minimum of six D (+) glucopyranose units attached by an -1,4 linkage.  Cyclodextrins are produced from starch by the action of bacterial amylase.  42
  • 43. 43 Host molecule Cavity for guest molecule Hydrophobic interior Hydrophilic entrance
  • 44.  The interior of the CD cavity is usually hydrophobic because of the CH2 groups, while the exterior of the cavity is hydrophilic because of the presence of the hydroxyl groups.  Complexation with CD does not ordinarily involve the formation of covalent bonds. Molecules of appropriate size and stereochemistry can be included in the cyclodextrin cavity by hydrophobic interaction. 44
  • 45.  The naturally occurring α-CD, β-CD and γ-CD contain 6, 7 and 8 units of glucose respectively.  The cyclodextrins form a ring and the molecule actually exists as a truncated cone in which guest molecules can be accommodated to form an inclusion complex.  The size of the cavity increases by increasing the number of glucose units, α -CD being the smallest, α -CD is not very useful for pharmaceutical applications, β-CD and γ-CD are more useful owing to the large cavity. 45