Download 5.New functional coordination compounds

Advanced Inorganic Chemistry
Oct. 9 – Dec. 25
Prof. Lu Jun
[email protected],
School of Science,
State Key Laboratory of Chemical Engineering
Huaxin Building , 204B
Chapter 3 Coordination chemistry
Aims and demands
 Stereoisomerism of coordination compounds
 Basic theory of chemical bonds of coordination
compounds (crystal field theory、ligand field theory)
 Reaction mechanism and kinetics characteristics of
coordination compounds
 New functional coordination compounds
contents
1. Basis of coordination chemistry
2. Coordination stereochemistry
3. Coordination chemistry theory
4. Reaction mechanism of complex
5. New functional coordination compounds
Section 1 Basis of coordination chemistry
1.1 History and development of coordination chemistry
1.2 Definition of coordination compounds and nomenclatue
1.3 Basic types of ligand and coordination ability
1.4 Classification of the coordination compounds
Section 1 Basis of coordination chemistry
1.1 History and development of coordination chemistry
In the 18th century (in 1704), the earliest record of the
coordination compounds in literature:
Fe4[Fe(CN)6]3 (prussian blue)
During the chinese ancient Zhou dynasty (1045 -221B.C.):
Synthesized red alizarin dye by madder root and clay/alumen
Red coordination compounds
contains Al3+, Ca2+
Section 1 Basis of coordination chemistry
1.1 History and development of coordination chemistry
In 1893, Swiss chemist Alfred Werner(26), published a famous paper:
1) the basic conception: modern coordination bond, coordination number, structure of
coordination compounds,
2) clarifying space configuration and isomerism of coordination compounds using idea of
stereochemistry.
3) the foundation of coordination chemistry, and marked the establishment of coordination
chemistry discipline.
Section 1 Basis of coordination chemistry
1.1 History and development of coordination chemistry
Many Nobel Prize winners associated with coordination chemistry:








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1913, Werner: Creating the coordination chemistry
1955, Ziegler and Natta: Metal olefin catalysts
1967, Eigen: Rapid response
1971, Lipscomb: Borane theory
1973, Wilkinson and Fischer: Developing organometallic chemistry
1982, Hoffmann: Isolobal theory
1983, Taube: Electron transfer mechanism of complexes
1987, Cram, Lehn and Pedersen: Supramolecular chemistry
1992, Marcus: Electron transmission theory
Section 1 Basis of coordination chemistry
1.1 History and development of coordination chemistry
Development direction of coordination chemistry:
 Synthesis and structural characterization of new functional
coordination compounds;
 Completeness and development of coordination chemistry theory;
 For biological sciences, form bioinorganic chemistry;
 For material sciences, form molecular functional materials;
 For supramolecular chemistry, structure molecular devices.
Section 1 Basis of coordination chemistry
1.2 Definition of coordination compounds and nomenclature
Definition of coordination compounds
Narrow sense: Coordination compounds are formed by
ligand and central atom according to certain composition and
space configurations.
Broad sense: The compound forming by atom A and atom B
or radical C, different from the original components, could be
considered as coordination ones.
Section 1 The basis of coordination chemistry
1.2 Definition of coordination compounds and nomenclature
Nomenclature of coordination compounds
The nomenclature of coordination compounds at
present in china is IUPAC nomenclature system, developed
and adopted by International Union of Pure and Applied
Chemistry (IUPAC), adapted by China Chemistry Society.
Section 1 The basis of coordination chemistry
1.3 Basic types of ligand and coordination ability
Monodentate , H2O, NH3, PR3
ligand
Multidentate , en, edta
Macrocyclic , crown ether, porphyrin,
Section 1 The basis of coordination chemistry
1.3 The basic types of ligand and coordination ability
bidentate ligand
Ethylene diamine
2,2- bipyridine
1,10-phenanthroline
β-diketone
Section 1 The basis of coordination chemistry
1.3 The basic types of ligand and coordination ability
tridentate ligand
Diethylene triamine
Section 1 The basis of coordination chemistry
1.3 The basic types of ligand and coordination ability
tetradentate ligand
N,N‘-Bis(salicylidene) ethylenediamine cobalt
salt
Section 1 The basis of coordination chemistry
1.3 Basic types of ligand and coordination ability
hexadentate ligand
EDTA
Section 1 The basis of coordination chemistry
1.3 Basic types of ligand and coordination ability
macrocyclic ligand - crown ether
18-crown-6 complexes
15-crown-5 complexes
Section 1 The basis of coordination chemistry
1.3 The basic types of ligand and coordination ability
macrocyclic ligand - cryptand
Cryptand[2,2,2]
Section 1 The basis of coordination chemistry
1.3 Basic types of ligand and coordination ability
coordination ability
From monodentate ligand to chelating ligand, macrocyclic
ligand, as the number of closed loop increases, their
chemical binding to central metal atoms was strengthened.
Section 1 The basis of coordination chemistry
1.4 Classification of the coordination compounds
Based on number of central atom
mononuclear and polynuclear coordination compound
Based on type of ligand
single ligand and mixed ligand coordination compound
Based on number of ligand
simple coordination compound, chelation, macrocyclic etc
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
2.2 Isomerism of coordination compounds
Section 2 Coordination stereochemistry
2.1 The geometry configuration of coordination compounds
The geometry configuration of coordination compounds is
closely related to the coordination number.
The coordination number of metal complex is between 2 to 8.
Rare earth metals has higher coordination number due to its
larger ionic radius, usually between 8 to 12, but 3d transition
metal mostly is 4 or 6.
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N = 2
Central metals are mainly Cu(I), Ag(I), Au(I), and Hg(II) (d10).
Linear molecular geometry.
Typical example: Cu(NH3)2+, AgCl2, Au(CN)2-, and HgCl2.
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.= 3
Central metals are mainly Cu(Ⅰ), Hg(Ⅱ), Pt(0).
Planar trigonal molecular geometry.
Typical examples: HgI3-, D3h point group.
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.= 4 (important configuration)
square planar (D4h)
tetrahedron (Td)
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.= 5
trigonal bipyramid
[CuCl5]3-
[CuBr5]3-
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
Configuration changes
trigonal bipyramid to tetragonal pyramid
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.= 6
regular octahedron (Oh)
tetragonal bipyramid (D4h)
regular
octahedron
Distortion
trigonal antiprism (D3d)
Section 2 Coordination stereochemistry
2.1 The geometry configuration of coordination compounds
tetragonal bipyramid (D4h) distorted along C4 axis
regular octahedron (Oh)
tetragonal bipyramid (D4h)
Section 2 Coordination stereochemistry
2.1 The geometry configuration of coordination compounds
trigonal antiprism (D3d) distorted along C3
regular octahedron (Oh)
trigonal antiprism (D3d)
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.= 7
single-capped octahedron (C3v)
pentagonal bipyramid (D5h)
single-capped triprism (C2v)
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.= 8
For complexes with c.n. > 8, central metal ion usually need to
satisfy the following conditions:
(1) larger radius;
(2) higher oxidation state;
(3) less d-electron.
Examples: Lanthanide, Actinide ions ( Ce(IV), U(VI) )
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.= 8
D4d
D2d
Oh
C2v
D6h
Section 2 Coordination stereochemistry
2.1 The geometry configuration of coordination compounds
C.N.= 9
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N.=10
Dodecahedron (D2)
Section 2 Coordination stereochemistry
2.1 Geometry configuration of coordination compounds
C.N. = 12
Icosahedron (Ih)
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
Definition of isomer
Isomers are defined as compounds having the
identical formula but different structures
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
Classification of isomers
ionization isomerism
hydration isomerism
constitutional isomerism
linkage isomerism
coordination isomerism
isomers
ligand isomerism
stereoisomerism
geometric isomerism
optical isomerism
Section 2 Coordination stereochemistry
2.2 The Isomerism of coordination compounds
2.2.1 ionization isomerism
The distribution of ligand is different between external and internal.
[Co(NH3)5Br]SO4
[Co(NH3)5(SO4)]Br
(violet)
(red)
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
2.2.2 hydration isomerism
[Cr(H2O)6]Cl3
(violet)
[Cr(H2O)5Cl]Cl2•H2O
(green)
[Cr(H2O)4Cl2]Cl•2H2O
(green)
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
2.2.3 linkage isomerism
ambident ligand NO2-
yellow
red
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
2.2.4 coordination isomerism
The distribution of ligand is different between complex
anion and cation.
[Co(NH3)6][Cr(OX)3] and [Cr(NH3)6][Co(OX)3]
[Cr(NH3)6][Cr(SCN)6] and [Cr(NH3)4(SCN)2][Cr(NH3)2(SCN)4]
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
2.2.5 ligand isomerism
1,2 - diaminopropane
methylene diamine
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
2.2.6 geometric isomerism (cis-trans isomerism)
planar square coordination compounds
Section 2 Coordination stereochemistry
2.2 The Isomerism of coordination compounds
2.2.6 geometric isomerism(cis-trans isomerism)
Octahedron complexes
 M(a4b2) type: cis-, and trans-;
 M(a3b3) type: fac-, and mer-;
Section 2 Coordination stereochemistry
2.2 The Isomerism of coordination compounds
2.2.6 geometric isomerism (cis-trans isomerism)
Section 2 Coordination stereochemistry
2.2 The Isomerism of coordination compounds
2.2.6 geometric isomerism(cis-trans isomerism)
octahedron comlexes：M(a2b2c2) type
3 trans-
1 trans- and 2 cis-
3 cis-
Section 2 Coordination stereochemistry
2.2 Isomerism of coordination compounds
2.2.7 optical isomerism
A molecule, if cannot overlap with its mirror image after
symmetric operation, it is called the optical isomer, or
chiral molecule.
Such as, cis-Co(en)(NO2)22+ is chiral.
Section 2 Coordination stereochemistry
2.2 The Isomerism of coordination compounds
2.2.7 optical isomerism
ethylene diamine
glycine
Section 3 Coordination chemistry theory
3.1 Development of coordination chemistry theory
3.2 Crystal field theory
3.3 Ligand field theory
Section 3 Coordination chemistry theory
3.1 Development of coordination chemistry theory
In 1893, Swiss chemist Alfred Werner, 26 years old,
published a famous paper. It gives the basic conception
of modern coordination bond, coordination number and
structure of coordination compounds.
Werner coordination theory plays a major role on the
development of coordination chemistry, and thus won
the Nobel Prize in chemistry in 1913.
Section 3 Coordination chemistry theory
3.1 The development of coordination chemistry theory
In 1929, L.Pauling put forward valence bond theory
of coordination compounds.
In 1929, Bethe and Van-Vleck put forward crystal
field theory of coordination compounds.
Later ligand field theory and molecular orbital theory
formed.
Section 3 Coordination chemistry theory
3.2 Crystal field theory
In 1929, Bethe put forward crystal field theory. Crystal
field theory is a static theory, but adding ligand makes
original quintuple degenerate d-orbitals losing
degeneracy of central atom.
d-orbitals
Section 3 Coordination chemistry theory
3.2 Crystal field theory
Basic point of crystal field theory:
(1) electrostatic interaction between M and L;
(2) degenerated d-orbit split in crystal field;
(3) d electron rearrangement within the splitted d orbits;
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(1) spherical symmetry field
Due to the negative charge of ligands distributed
spherically, no matter where d-orbit is, the repulsive
interaction of the negative charge is the same,
although of the d-orbital energy increases, still keep
quintet degenerate d-orbitals.
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(2) regular octahedron field
In regular octahedron field, the repulsive interaction of 5 d-orbitals
will no longer be the identical.
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(2) regular octahedron field
free ion
spherical
symmetry
field
regular octahedron
field
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(2) regular octahedron field
Energy level splitting conforms to the center of
gravity conservation principle.
2E(eg)＋3E(t2g)＝0
E(eg)－E(t2g)＝△o
E(eg)＝0.6△o = 6Dq
E(t2g)＝－0.4△o =－4Dq
△o/10Dq is eg and t2g orbit energy difference
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(3) elongated regular octahedron field
In elongated regular octahedron field, eg and t2g orbit
will split further.
Energy order (from high to low):
① dx2-y2,②dz2,③dxy,④dxz and dyz
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(4) square planar field
In square planar field, eg and t2g orbit also will occur
to split further.
Energy order (from high to low):
① dx2-y2,②dxy,③dz2,④dxz and dyz
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(5) regular tetrahedron field
free ion
spherical
symmetry
field
regular tetrahedron field
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
(5) regular tetrahedron field
According to the center of gravity conservation
principle:
△t＝E(t2)－E(e)＝(4/9)△o
3E(t2)＋2 E(e)＝0
Calculated: E(t2)＝1.78Dq E(e)＝－2.67Dq
Section 3 Coordination chemistry theory
3.2 Crystal field theory
d-orbit energy level splitting
Section 3 Coordination chemistry theory
3.2 Crystal field theory
Splitting energy and its influence factors:
(1) the type of ligand field
such as: △t = (4/9)△o
(2) the oxidation state and radius of center ion
Ion Co(H2O)62+
Δo(cm-1) 9300
Co(H2O)63+
18600
Co(NH3)62+
10100
the higher oxidation state，the larger Δ
Co(NH3)63+
23000
Section 3 Coordination chemistry theory
3.2 Crystal field theory
Splitting energy and its influence factors:
(3) the types of ligands
Such as:
ion
Δo(cm-1)
Cu(H2O)62+
12600
Cu(NH3)42+
15100
Cu(en)32+
16400
for the same metal ion，Δo is different with different ligands
Section 3 Coordination chemistry theory
3.2 Crystal field theory
Splitting energy and its influence factors:
(3) the types of ligands
spectrochemistry order: splitting energy of common
ligand arrange from small to large.
(weak field) I- < Br- < S2- < Cl- < SCN- < NO3- < F- < OH- <
H2O< NCS- < NH3 < en < bipy < phen < NO2- < CN- < CO
(strong field)
Section 3 Coordination chemistry theory
3.2 Crystal field theory
Low-spin predictions of complexes
High spin arrangement
Weak Field
Low spin arrangement
Strong field
Obviously, only one arrangement in d1, d2, d3, d8, d9, d10 , no difference
between high and low spin.
Section 3 Coordination chemistry theory
3.2 Crystal field theory
Limitations of crystal field theory
Crystal field theory can be better to illustrate the main
issues of stereochemistry complexes and thermodynamic
properties, but it can not reasonably explain the
spectrochemistry order of ligands.
This is due to the crystal field theory without considering
the overlap of metal ions and ligands tracks, that does not
recognize the existence of the covalent bond. Modern
experimental determination indicate that the track rails of the
ligands and the metal ions are indeed overlap.
Section 3 Coordination chemistry theory
3.3 Ligand field theory
Solution of crystal field theory limitations
covalent bonds
molecular orbital theory
Propose
crystal field calculation method
Base on
Crystal field theory
Ligand field theory.
Section 3 Coordination chemistry theory
3.3 Ligand field theory
Key points of complex ligand field theory
(1) the ligand is not a point charge without details, but there is a
certain charge distribution.
(2) The binding contain both the electrostatic and covalent
interactions.
Section 4 Reaction mechanism of complex
4.1 Active and inertia of coordination compounds
4.2 The mechanism for substitution reactions
4.3 Factors of influencing the substitution reaction rate
Section 4 Reaction mechanism of complex
4.1 The active and inertia of coordination compounds
Active coordination compounds: fast ligand exchange in
substitution reaction;
Inertia coordination compounds: slow ligand exchange in
substitution reaction.
Coordination compounds activity base on the kinetics, but
coordination compounds stability base on the thermodynamics.
Section 4 Reaction mechanism of complex
4.1 The active and inertia of coordination compounds
activator
activation energy
activity
reaction energy
stability
reactant
product
Section 4 Reaction mechanism of complex
4.2 The mechanism for substitution reactions
Substitution reactions mechanism:
nucleophilic substitution(SN): MLn + Y → MLn-1Y + L
electrophilic substitution(SE): MLn + M’ → M’Ln + M
nucleophilic substitution: SN1 and SN2 mechanism
Section 4 Reaction mechanism of complex
4.2 The mechanism for substitution reactions
1 SN1 reaction mechanism(mono-molecule substitution reactions)
two steps:
(1) ML6 → ML5 + L
(slow) (C.N. = 5)
(2) ML5 + Y → ML5Y (fast)
The first step is to determine the rate of reaction, and the
total rate depends on [ML6]. Such as:
（1） M(H2O)62+ → M(H2O)52+ + H2O (slow) ( M = Cu……)
（2） M(H2O)52+ + H2O* → [M(H2O)5(H2O*)]2+ (fast)
Section 4 Reaction mechanism of complex
4.2 The mechanism for substitution reactions
2. SN2 reaction mechanism(bimolecular substitution reactions)
two steps: (1) MLn + Y → MLnY (slow) (C.N. = 7)
(2) MLnY → MLn-1Y ＋ L (fast)
The total rate depends on [MLn] and [Y]. Such as:
[Pt(NH3)3Cl]+ + Br- → [Pt(NH3)3Br]+ + Clrate equation: v = k[Pt(NH3)3Cl+][Br-] 2nd-order reaction
Section 4 Reaction mechanism of complex
4.3 Factors of influencing the substitution reaction rate
key factor:
Static electricity theory
Internal and external orbital theory(Taube rule)
Crystal field theory
Section 4 Reaction mechanism of complex
4.3 Factors of influencing the substitution reaction rate
4.3.1 Static electricity theory
key factor: the Z and r of M, L, Y
SN1:
larger r of L, M-L bond easily breaking, be beneficial to SN1
such as: [Co(NH3)5Br]2+ + H2O = [Co(NH3)5(H2O)]3 ++ Br[Co(NH3)5Cl]2+ + H2O = [Co(NH3)5(H2O)]2 ++ Cl-
(fast)
(slow)
lower Z of M, M-L bond easily breaking, be beneficial to SN1,
such as: [Fe(H2O)6]2 ++ H2O* = [Fe(H2O)5(H2O*)]2+ + H2O (fast)
[Fe(H2O)6]3 ++ H2O* = [Fe(H2O)5(H2O*)]3+ + H2O (slow)
Section 4 Reaction mechanism of complex
4.3 Factors of influencing the substitution reaction rate
4.3.1 Static electricity theory
SN2:
smaller r, higher Z of L, and higher Z of M, be beneficial to SN2
[Co(NH3)5(H2O)]2+ + I- = [Co(NH3)5I]+ + H2O
[Co(NH3)5(H2O)]2++ Cl- = [Co(NH3)5Cl]+ + H2O
(slow)
(fast)
Section 4 Reaction mechanism of complex
4.3 Factors of influencing the substitution reaction rate
4.3.2 Internal and external orbital theory(Taube rule)
activity
Inertia
Section 4 Reaction mechanism of complex
4.3 Factors of influencing the substitution reaction rate
4.3.3 Crystal field theory
CFAE = CFSE(Oh) - CFSE(int)
CFAE- Crystal field activation energy;
CFSE(Oh)- Crystal field stabilization energy;
CFSE(int) – intermediate crystal field stabilization energy
great CFAE represent inertia complex, otherwise activation
complex
5.New functional coordination compounds
As development of advanced technology , research about functional
complexes (molecular-based magnetic materials) with special optical ,
electric , thermal , magnetic character was developed rapidly .
Conductive complexes
Magnetic complexes
Nonlinear optical complexes
Photoluminescence complexes
Electroluminescent complexes
Medical complexes
5.New functional coordination compounds
The research of molecule-based materials is a new and hot
science between chemistry, physics, biology.
Molecule-based materials is defined as useful substances with
molecules compose combined with molecules or changed molecules.
As the different optical, magnetic, electrical characters of
molecule-based materials , we can call them as optical molecularbased material, molecular conductor and molecular magnetic
materials.
5.New functional coordination compounds
5.1 Conductive Complexes
5.2 Magnetic Complexes
5.3 photoluminescence/electroluminescence complexes
5.4 Medical Complexes
5.5 Coordination Polymers
5.New functional coordination compounds
5.1 Conductive complexes
Conductive complexes ( molecular conductor )
have their own superiority
1) small density (1.5~2.0 g·cm-3,vs. copper:
8.9g·cm-3 );
2) easy to adjust and reform;
3) Suitable for molecular electronics.
5.New functional coordination compounds
5.1 Conductive complexes
Conductive complexes can divide into two broad categories:
Low dimensional coordination polymers: phenolphthalein
porphyrin
Charge transfer complexs: Fullerene , metal salt ,we can also call
them electron
donors–receptor ligand compound
5.New functional coordination compounds
5.1 Conductive complexes
Low dimensional coordination polymers: It can show the
characteristics of the molecular conductor when the aggregation
state of conjugate surface complexes are stratified structure .
According to the type of interactions between the molecules of this
kind of conductive polymer ligand, we can divided into:
M - M, M – p, and p - p three categories.
5.New functional coordination compounds
5.1 Conductive complexes
M-M type low dimensional coordination polymers :
K2[Pt(CN)4]Br0.3·3H2O is relied on the extending of
the dz2 orbital overlap of neighboring central metal
ion (M - M type, the distance between metal ion
usually less than 0.3 nm) , it can form onedimensional metal conductive channel which
electrons can transmission between column.
5.New functional coordination compounds
5.1 Conductive complexes
This kind of one-dimensional molecular crystal metal
properties satisfy the two conditions:
 Part of its structural units (molecular) HOMO orbit was
occupied.
 Crystal molecular arrangement is beneficial to the
frontier orbital overlap between moleculars.
The 1D conductor has the following characteristics:
 Strong anisotropy
5.New functional coordination compounds
5.1 Conductive complexes
Low dimensional coordination polymers (M-M type)
Phthalocyanine (pc) is a kind of macrocyclic plane conjugated
ligands with 18 p electronic system (N4 ligand). Phthalocyanine
complexes doped iodine after partial oxidation, their energy gap
decreases, conduction band and valence band width, the
conductivity significantly increased.
For Pt, Fe, Ru and Mn coordination polymers, their conductive
(M - M type) form was obtained by the metal atoms dz2 orbital
overlap .The carrier is electron.
5.New functional coordination compounds
5.1 Conductive complexes
Low dimensional coordination polymers (π -π type)
For Cu, Ni and other coordination polymer，the p-orbit
overlapping of the phthalocyanine ligand molecular form
the one dimensional conductive column which plays a role
of electronic transferring (hole).
In this type of metal complexes, the electrical conductivity is
only influenced by π -π overlapping of macrocyclic ligands and
has nothing to do with the metal center.
5.New functional coordination compounds
5.1 Conductive complexes
Low dimensional coordination polymers (M -π type)
In one-dimensional polymer phthalocyanine metal complexes
use conjugate molecules as bridging ligand , when the metal dxz
and dyz orbital overlap track and large ring dentate orbital,
forbidden band width become smaller and the M -π type can
show the electrical conductivity.
[PcMCN] ∝(M = Cr, Mn , Fe, Co and Rh etc) show the
conductivity of 10-4~10-2S·cm-1 without dopping
5.New functional coordination compounds
5.1 Conductive complexes
Charge transfer complexes: The molecular metallic
charge transfer salt formed by the electron donor D and
electron acceptor A can be divided into three categories,
DA, DX and CA type
(C represent for cation, X represent for anion).
But the conductive mainly comes from part D and A.
5.New functional coordination compounds
5.1 Conductive complexes
From the electronic and spatial structure theory, many electron
donors and acceptors was designed and sythesized.
5.New functional coordination compounds
5.1 Conductive complexes
Electron accepter
5.New functional coordination compounds
5.1 Conductive complexes
The charge transfer complexes is also called the electron donoracceptor ligand compounds:
 The first organic metal was obtained by combination with donor–
acceptor (TTF:TCNQ 1:1) with metal electrical conductivity.
(DA type)
 In 1980, The first atmospheric molecular superconductors
(TMTST)2ClO4 was prepared by tetramethyl four selenium
fulvalence .(DX type)
5.New functional coordination compounds
5.1 Conductive complexes
DA Conductor
As the first organic metal TTF-TCNQ, the concept of nature
organic matter and complexes was changed. In this compound,
charge transfer occurred between the electron donors TTF (D)
and the receptor TCNQ (A) .
5.New functional coordination compounds
5.1 Conductive complexes
DX Conductor
Typical representative of the first generation of organic
superconductor compounds (TMTSF)2X (X represent for anion,
such as PF6-, AsF6-, ClO4-, etc), can turn to superconductors with
pressure.
5.New functional coordination compounds
5.1 Conductive complexes
Outlook
Various types of excellent conductors, even the low
temperature superconductors through the research on
conductive complexes have been obtained. They are small
crystals with poor mechanical strength, unlike traditional
metal superconductors which can be processed. It is possible
to make semiconductor molecules into the superconductor by
modifying the structure of complexes and was potentially
available as the molecular electronic devices in the future.
That’s why physicists, materials scientists and biologists pay
attention to it.
5.New functional coordination compounds
5.2 Magnetic complexes
Magnetic complexes easily soluble in organic solvent which
make it possible to obtain special magnetic material by ordinary
chemical reaction in normal conditions. And molecular
ferromagnet has advantages of small volume, light weight,
various structures and easy to processing molding, can be used
for aerospace materials, microwave absorption stealth materials,
electromagnetic shielding materials and information storage
materials, etc.
It is a hot research field of coordination chemistry to synthesis
molecular ferromagnet complexes with high phase transition
temperature (Tc, known as the critical temperature).
5.New functional coordination compounds
5.2 Magnetic complexes
Currently, magnetic complexes is the most widely researched of
the molecular magnets, it can be formed mononuclear and
binuclear and polynuclear complexes. It can form a onedimensional, two-dimensional and three-dimensional molecular
magnets by proper molecular assembly of high spin complexes.
5.New functional coordination compounds
5.2 Magnetic complexes
molecule ferromagnet:
[{NiII(tn)2}5{FeIII(CN)6}3]n(ClO4)n·2.5nH2O
reaction :
1,3-propylene amine,
Ni(ClO4)2·6H2O,
K3[Fe(CN)6].
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
When illuminate some substances, these substances will emit
visible light with various wavelength and intensity, When the
illuminattion stop, the light emission also disappear, which is
called photoluminescence (PL).
And the electroluminescent(EL) is about the material can be
sparked by the corresponding electricity to produce luminescence
phenomenon under a certain electric field.
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
The photoluminescence and electroluminescence have common
research point what is having a high luminous efficiency.
Due to the special molecular structure of the metal complexes ,
on the one hand, its molecular structure rigidity, on the other
hand, its molecular stability.
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
Light-emitting principle: ligand center light-emitting
Metal complexes as a molecular whole, light
absorbed by the ligand of photosensitive
functional groups, and luminescence was
originated from the electron transition
between the orbitals on the ligands.
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
Metal ions, the equivalent of a inert
atoms, combine with different parts of
the organic ligands form chelate ring.
And the original nonrigid flat structure
change into a rigid plane one, which
resulted in organic compounds without
fluorescence into a strong fluorescence
complexes.
For example, non-fluorescence 8hydroxyquinoline have the green
fluoresence in the chelate of tris (8hydroxyquinoline) aluminium (AlQ3) .
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
Light-emitting principle: the light-emitting on center ion
If the m* level is below the T1 level in the
complexes , it will happen the intramolecular
energy transfer as :
S1 T1
m*.
This complexes of metal ions sensitized by
organic match physical quantity transfer,
its fluorescence intensity is much stronger
than pure inorganic metallic ion.
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
Rare earth complexes with high luminescence efficiency and high
color purity, covering the visible area.
Advantages:
 narrow half-peak width;
 modify the structure of the ligand does not affect the luminescence
spectra of center ion
Applications:
 agricultural luminescent material, anti-counterfeiting materials,
fluorescent and color display, electroluminescent
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
(1) Application in agriculture
Rare earth complexes luminescence materials can effectively
transform the sun‘s ultraviolet light into a red orange light which
benefit for crop growth. The fluorescent conversion agricultural
film (turn light film) based on the rare earth complexes can be
used for vegetables, seedings, flowers, etc.
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
(2) Primary fluorescence and the application in color display
Polymer complexes containing rare earth Ln3+, Tb3+ and Eu2+ can
produce red, green and blue color fluorescence under uv
excitation ,they can be made in three primary colors of composite
polymer materials, plastic type tricolor fluorescent lights or color
display
5.New functional coordination compounds
5.3 Photoluminescence/Electroluminescent complexes
(3) Medical application of the rare earth complexes as fluorescent
markers
Fluorescent tags -- fluorescence immunity analysis.
 Long fluorescent life of the rare earth complexes
 Sharp band
 High sensitivity in extremely dilute concentrations
serum protein
 the application prospect is very optimistic.
5.New functional coordination compounds
5.4 Medical Complexes
Platinum Antitumor Drugs
Complexes of platinum are the most widely used anticancer
drugs, there are four complexes in clinical use, in addition to, a
dozen complexes are on different stages of clinical trials,
including an oral administration tetravalent platinum
compound.
(1) cisplatin
1965 discovered by American physiologist B. Rosenberg;
1978 approved for clinical use in the United States - the first
inorganic anti-cancer substances
1997 comprehensive evaluation of anti-cancer drugs by World Health
Organization
Cisplatin ranked second (Adriamycin ranked first)
Combination with cisplatin anti-cancer drugs - control or delay vomiting
ondansetron, paclitaxel
5.4 Medical Complexes
(1).Cisplatin
First generation
Advantages:
Strong anti-cancer effect, high anti-cancer activity, conducive to
clinical drug combination
Disadvantages:
Cause strong nausea and vomiting, toxic side effects, nephrotoxicity
Anticancer application of cisplatin :
ovarian cancer, lung cancer, cervical cancer,
nasopharyngeal cancer, head and neck squamous cell
carcinoma, prostate cancer, bladder cancer, testicular
cancer, lymphosarcoma.
5.4 Medical Complexes
(2).Carboplatin
Second generation
• In the 1980s, U.S. Bristol Myers Squibb, Cancer Research UK, and
Johnson Matthey company jointly develop the carboplatin;
• In 1990 carboplatin was successful developed in our country
and approved listing.
5.4 Medical Complexes
(2).Carboplatin
• Good chemical stability - effectively reduce the vomiting
• Good water solubility, 16 times of cisplatin - effectively reduce the
nephrotoxicity
• Myelosuppression, large blood toxicity
If cisplatin is prescriptible for the cancer , carboplatin is
also prescriptible, and the side effects (non-blood system)
and induced vomiting of carboplatin is less than cisplatin,
so people inclined to use carboplatin in current clinical.
5.4 Medical Complexes
(3).Nedaplatin
Second generation
• Features:
No renal toxicity after
hydration and diuresis;
Bone marrow suppression
(Similar with carboplatin)
Pharmacodynamic application of Nedaplatin :
• leukemia, lung cancer, melanoma -- Anti-tumor effects better than
cisplatin
• head and neck cancer, testicular cancer, esophageal cancer, bladder
cancer, ovarian cancer, cervical cancer-- Promised rate ≧ 25%
• If cisplatin is prescriptible for the cancer , Nedaplatin is also
prescriptible, and the effect of Nedaplatin is similar to or even better
than cisplatin
5.4 Medical Complexes
(4).Oxaliplatin
Third generation
•Be curative for leukemia (cisplatin resistance, that is non-active efficacy)
•Good effect activity for the advanced colorectal cancer (colon cancer)
• Good effect for a variety of tumors-- colorectal cancer, breast cancer, ovarian
cancer -- and even has inhibitory effect for the first and second generation
platinum-based anticancer drug-resistant strains
5.4 Medical Complexes
(5).Lobaplatin
Third generation
 Equal or better efficacy than the first-generation and
second-generation;
 Considerable toxicity with carboplatin and no crossresistance with cisplatin;
 Good effect on the esophageal cancer.
5.4 Medical Complexes
(6). Other third-generation platinum-based anticancer drugs
• Ring Platinum -- Less toxic than cisplatin (thrombocytopenia),
high activity than carboplatin; poor specificity, easy to damage
normal cells
• BBR3464-- Triple platinum complexes, multi-bonded with DNA,
strong damage to DNA , high anti-tumor activity
• ZD0473-- High activity of the tumor cells for secondgeneration drug resistance, orally active
5.4 Medical Complexes
Gadolinium complex and magnetic resonance imaging (MRI)
MRI technology has become one of the most powerful clinical
diagnostic testing means.
 Diagnosis of the disease: using the foreign paramagnetic
agents or imaging agent to make 1H(mainly water) in the
normal and diseased tissues to produce a difference in
resonance signals.
Magnetic resonance contrast agents make proton relaxation
time shortened, thus it improve tissue imaging results.
Most magnetic resonance imaging agents are Gd (III), Mn (II)
and Fe (III) complexes etc. .
5.5 Coordination Polymers
Coordination Polymers
The concept of coordination polymers. was first proposed in J. Am.
Chem. Soc. by R.Robson in 1989 .
The first coordination polymer synthesized by Robson is a threedimensional polymer built by the monovalent copper ions with the
organic ligand 4,4 ', 4 ", 4"' - 4-cyano-phenyl-methane .
Similar to the three-dimensional network structure of diamond configuration.
5.5 Coordination Polymers
Coordination Polymers
Maintain the characteristics of both the organic polymer
and inorganic metal ;
Polymer materials with new structure and peculiar
properties;
It may become functional materials with thermal,
electrical, magnetic, catalytic and biological effects;
One of the most attractive research direction in inorganic
chemistry, materials chemistry , life sciences and other
fields .