7 19

Coordmation Cet Chem istry

K4Fe(c)e Co mp ox Potasum avacyorido feunotte

(T)

Cacl Simpla alt

tesOq, (N H), S0 6tt20 Double sa
K2SO4 Al2 (so) g 24 Hg0
5
+ -2
Na[fe(cN)s NO Sodium pentaoyanide nitrosylferotL(L)

Na, Ltel Sodium tetrach lorido pla tinate (T)

Active charIcoal -catalys
CoCl2 in ammoniacal medium [Co(NH2) C
n ha se!> qowe tes tfov only
C D ange e77s tal

co(NDgag > 3 eleckrolyte m.b: molueulLan wt.

eond uctivity
co(H) c]a :2
S4HSO4t KoC1,0, (solid) COgCl21
pased tor. NaOHs elh

Warnu compouds redish broum

+3
g No,CrO 4
Co(NHa)C3 CoNH) 3C Acidify
Hexaamminecobalt(TI) : ch laride Pb (CHcoo
61
+2
Co(NHa)s C Cl2 [eo NH),] 2 PhCr0y
yello pp
ddex Pentoaminechloridocobalt () ckloride
Tn his ABfred
coordinat ion theory Wennan introdu eed two 4.11
deas
greak

In a coordination complax ,a metal ion is

engaged in a strong
binding oith a etain no.
ofeutral (Hg, H0 ete, ) and/ or
mome
qroups (F", u, CN ete.) in te
first sphne of attaetian,
no caled esordination 2one/sph ere.
t1 Tu metal ion
swwoundod by the
naubralfer and/or anioune.
grous nm a deinite geometrieal anangonment.
 NH4OH
4TFe (e)
jivst coondimation 207e +2 Coordination stake.
C.N 6
WeYnen guad thak metatl ton possessed two kinds otvalence
a
primay valenee and a secondany valenee. Primalry valence

i satisfied by, anionja or negat ive groups being present inside «nd
equiste no. of
on
outsid e the eordi
nation sphne. Seeonday valenea indieates he
eapacity o th mutal ion centain no
to ace omodate
otaroup6 in the Prat
sphne ot atlraction, m
Primary oth coordinahon
State
valnee
y val ene iss e noud
now
"equated
and aecondany valemce wrthk the coordi nakion no, ot +he mata
LOn

A
metal
ion (twhethn it i +ve Iy eha1ged
, eutral oreven
Ohged) may combine wth nt
ral moleculs oor onuons
onions to
tc grve a
entity
ne n asonably identifiable oalia
d complex. Te
a
7oubs that ane
Demd/igaked
A
int to the metal ion
in a
comptay one called
A
igands one
aianged aruound igands.
th
attraetion (eoodination One) in metal io tnstde the firat spuane n

ligands bound aiound pveferned acometry. Th no. of

ametal ion by bends i
nation no, ot thi metal ion. oalled coordi-

M
+ L ML
4.
Tn thus Tm thu metal ion Mtreacy
TRactg with
ith t*t autral
L(eapabt of taking 1 eoordination * o
n .
no. neutral liganddind
poaition) ML" Here to fovm
nYepresents tho oordination umban. In [Co
(nH c.N. 8
 Clauwication of digonds 2119

Monodentake T will cooTdinate. but wlllnot

N
H Aartisfy thi change of th malas
ion
PYTidine
n,
2. Bidentate ampine
CHCHa
H,N NH2
a etkylena diamin
Cer)
Coo
HN-CH2 ayeinale anion
aron 2, 2-bipridine
a

-bhonan torotene
y I t0 phenanthroine (-bhn)
C 0
Oxalake
S.
C=0 Bidentake bintgative
e- igand
3. Trident ate Diethytanu triamine

CH2 CH H2
NH
NH2 (dien)

4. Tatradentate
Triethyune tetramine
NH
nd HaN NH

. Penkordshtote Ehyundiamiu triacetie acid,.omian

Pentadentate
NC C-09

0-e-Ho NH +ri ngahve

CHC-0-
Hexodentate Elhyundiamin tetro acckie acid aruo

EDTA
N Coo
OC
Compluxo ne- COoe
coo
eomplurin8 gmt/coovdinating agent/
Cm Kse7 K. Aequustourg and

Felun 34

Hexaaguairon (Lion 29.1 19

Fe(H Cl
Hexaaquairon () chloride
KLFe(cNE Pofasium hexaeyanidoferrate (T

Feleo)s Pentacan bonylivon (o) fe2 Co)

Feg (C0)12
Hexaamineeobalk (TD) hexacyani do chnomake ( )

Anions ending in 5.2-19

ide, i and ate'
ido to, 'ato ane
changed Tespectively to

Fluoridee
fluorido (F-)
Chloride
ehdorido (Cu)
Bromide
bromido (T)
1odido
OH
hyd roxide

hydrido
CN
cyanido
02
oxido
 CoCCl), CwHa)3]> Triamminetrichloridowcobalk (1T)
LCo Cl(NH, Me),
Trichloridetru(methylammine cobalk(T
LeCN)(PDchj> sMonatmminediehloridomonepyridine platinum(T)
LCu Ng(NH), Pentaammineaeido coppen im
IL
Sauaneplaran
LCo N (NH)e Pentaamimineaeido cobalt () ion

Pentaamminechloridocobalt (r chlride
Na [fe(cN), NO Sodium pentaeyanido nitroayl fernateC)
P( ] Diehloridodiammin -Dieh. DiammingdicAlorido plakinum
(T

C
PE
NH
eis platin

AuXa 2 Tetraxenon
old
i d o n r IL) ion

Tomerism 192 1 9

Linkage I40mAriSm.
Hydrate
n Tonsadion
Støwoisomerism yeometrieal and Optieal)
Stersoisomtl4m ia a form oti4omenism in okieh te complures ef
idantieal fivst apheve composition dijfer only in th relative
oalso temue
posittoning et tha eoordinating groubs. Such in omsu aru
qeomotieal inomeru aince tis gives ríse to diffevent sat spai
auangement ot coovdinaking groubs wtwn tha Aom ovenall geo"7
c the compu x 20n.

Square planaj Pd2 may s9,plana

nict,2 le tetrakadral
Tetrahdral Pt 24
Pt Sqplana
Td Plam an
octahn dral the twu
may qivo rise to stereolso mem. Ho weve qeomatrieal
dis poaui on

Can not arise in Td

Y
geometrical isomsru
diapoa ition because in terahudron- each
e igands
equdis tant Prom th othwv u and all bond
identieal. However in
Jingths i au

Aq planan omd Oh
eomp layes this
ab undant. isomuum
PH
(NHg), Ci, Diamminodichteridoplad inum (1T)
C NH3 C pt NH3
Pt
C NHa
N
cis (-trm)
trom (8-form)
Ingenmval MA 82 0Y
MA BC can exist in tso
orm geomatrical tsomwie
es-PE CNHe 4, 250 C
trams vaniety
PC[PE C]-NH3 in Ha
NHCl a bujfn cis votiaty V

a r.t (Ca. 852)

tras voTiety is nit.
 C NH3
- C
Pt
C
NH2
7
al PECI NH3
NHPt NH3 Cc)
2-
Cl C 7 C
Pt NH P cl NH
CI
Pt
amds NH3
The Clqoup
e Ci
group oill in vite thks second NH at its troms posi tion more

m pTOnouneedly than NH
e
relakive
to
tendency ota ligand
Pt(T) sq.plam ov compluy
in a
directa ineoming
for diffeunt ligands Aubstituunt to its tran position being diif
divecting calfed th trams was
ti rtfect. In
troms effeck ot C
exonp
NH
26:219
NH3
A CH 8
Tdentify A, B, Cand D
C2Hy NH3 dD
ie D
A Pt NH N H
C B PE
C C

C C H
C
PE C
D PE
C
HN C
Tras etfeek ot C
NH3
ilPt, NH3 Pt NO 2 Cl
PE
C NH3 oN NH3
NO2 82 2
cpt NH3 CI
P
NO2
HaN

ITaeffeck ot C2 H4 and NO, c

H > No Nn
PiCIPCI]
- 1

PR3 CI
A -pt
iyPtCPa) 24 CI
+T
PR3 PR3
Pt
CI
PR3
Vi) cia - CI
Pt(NH:), Cl2

HN

24
u-PECHs), (),
Nh

Sight exco% iv
tu

Trom effe ck ttu i s ve igh, 7>

e r No, NH
2
tu NH 2+
Tram P (NH) Cl
u
NH HN
axcA tu

NH3 2
Pt Cno chong)
3N

Based on qualitati va amdsemkquantitative timation obcervation th

V
igonds aommonly found in Pt(T) compuras howe been arvnange d
into an
approxi make incTeaj ing onden ot hun troms- dlrecting
infuance, knoon as thu trams elfet senies,

H0 OH ycine sHg RNH2 <Py weok

*
CIBr T sCN Ng Modanata
NO, thiowua ugkusk
*
[Lenge
{PR3 AsRg Rp S NO co CaH4 (CN very lgeJ
*
C CeHSCH
30 70
PEts H
IF000 8000
.. At 25 c +hs relativa nates for th displace mant ot Ci in
othamstie medium for trams Pt (PE), ECI LE Monooanio
dent nie
ake
Pyridine is given in th above Sonies, Elueidate thu
mon
ligand
Tesult;
 |20
c
PE d by C PEt
P Pt
FtP CI FP

R P S a n k a r l

2.3 9
Thuovies of Tras effect
Polavisation thuory (besterplaind) tlas mo mathematical fowdakon
OTbital mixing(d-mixinq)
aberga Polanisation tuory is thu first sueeemful thuory to axplain
trom effeck In
symmetrical complay Ptx thune will be no nut
a

polari sat ion of thu eentral Pt)

Replacement of on * by igand L
Cmore polarising than x ill induce nut
guch tha the
a
polarisation in the Pt eantre
-Ve end is elase to the
qroub X trans to L
causng
aoeakening ot the M-x bond
(PE-x) trons to L.
bond will be Consequntly tkis
preferentially ruptured. This thory
eobsaTved parallelism aueces.sfuly planed
bekween thi magnitud1
othe groups ot he tramseffeck

PE
x-Pt 6-L+
Net
polrisation() =
o
 rbital Mixing theory Civen by Eduard and Pearson Aec ording .
to thm
atate vkich wkin
polanisiblity resulk from tha exietmce ot low lying eeite d
mixed oith the ground states, produces polanity Th polanisibility of T*
Rsulks from ts ability t #empty d' ovbitals to mixet oth fill ed borbrt

+ (4 orbital)

Move mi¥ing - MOre polavisation (orbit) raws bond beeomes weak.

Secondany valencas ane direeted in space. Comment on this statemextiw

the Ligkt ot Wou the

re
neT metallie eomplexes

2t
P $2-7

Ni(era > Octahdral

an-does not satisfy primary

is
valence ence it is not innermttallic ex.
Tetraphenyl } borate -

Callianost. (bulky cakion)

d
Coordinakion complaxps in which both
secondany valenee as
well as prima7
valunee ane
satisfied by, already present (inner) igand is ealled
the one
innn matall ic
complex.

fackovs ofecing the stabitlty of compluy akel ate efect

19 3 19

Thermodynamic stabiuty
i) Kinatie stabiib.
MnL
MLn
staoility eovstant
[MLn
For the det
etminatton ot thau u an
aiumptron Stepuwte foma tron
oh eompoumd
 ML ML

k, [ML

L L ML2 K [ML

Kn ML]
[H LJ"
B: Kx K X .x
Ky

n k, * K2 * Kg * xKn
Kn
Le Thie stan dmd free enwngy change AG
.
G - RTAn k «

2'303 RT Sog
(can be detesmind
Stabillty costant can be axperumentalliy
dokerminud .
-308 PT log B 4H°- T4s
9 303 R log B |4- 4s

Siabiity of a coordinakon com play in a soutjon tobe enhanead

if H decra^e and/or S incTea
What ww fhe thomod yna mie roguinements for t enhaneemint ot
f stabiuty eta coordin ation complax
 FactoTs
Aadsral Natune ot metal
nigomd.-
Solvont.

)he stability comtant inereoses ith deere as e in s12e ot a matal

ion, Fe"/Fe34

inereases with inerease in ehange ot

central tal fon
The ions with higkonpolaisibiity give
compluxes oith ghen F.
more
eluetro ngakiuity stabu eompure.
7) Basicity of ligond The greaten is tu Leuois base strength th highun
expeeke.d thu _B.
T dibola
mamen and polanisibility dtt ligand. inc reases 3.
iy r bornding inereasos stabitity.Ni(Co)4
Ster ie factor 3Solwent ePfeet! Like di olves Jike.
Chlake effect Dielsctric eostanl

Th extTa stabiuty confprne d thu

by eemnplaees press ene e t the
Chelakeing in a metal compla x is twmed a 4ha
chelate effect
Ihe enhanced
stabiluty confevmed by pelydentote Jigond
in Jieu of
mondentate counknponta
POtA in aa metal
meta compkxa-is tenmed as the
d anchoringet its
chelate afeck
Ta taliity tPt(en) 2 24
t s stability ot Pt(UH)
 26 3 19
Optical Tsomerism
VV.E

J any q uare plan an/ octahudral compo un ds

than
do not have or
thy will auou eptioal isomerism.
p t eal isomers - differ only m the dlrectlon in ohich they 7otake thu

Pla of poloiisation ot plane polastised ight and o e called enantio mwa.

exist m obtact mirror
and otun ia
image velotionship, one is
-

dextro Totato ry (d)

Javo vot atory ().
TAt molon zotation baing tha zome for thi anantio merie pauS.
oy
t manifestation ot optical h activity tu compound must be
devoid ot a
cuntre?, o plana ot AYmmetry
Octahedal 06tieal Isomers
CI
9+
Co (MH), C NH3
tHNCco N 7
NH3 HN NH
CI N43
Optically inactive

CalwCl CI
en etkylene diamine

Ct
N
Co
C
C N
19 The cis form doey not hawe any plant or centre of m metry t. e. cus

fovm is optically aactive.

trag - form has 6.
CH3
pn HN-CH-CH-NH2
34

e(,] Th eompo und can axist in d/ form & octahdrad

opti eally active co ( m) comp Luxes ore
thsoretically
possible. Howeve7 dw to tnmody namie comtrain,
(Ea is lou) oll isome not be
a)
can expeTimentally
Tesolvad.
AICAB),X2 and Fe(AB),x,eomplsxe ans octaud rat. Howwe
t y au not res odvab lk du to dow enwng of actvation of thu racmisaio
pTOCC.

24.19
Elucidate thu structne based on
hybridisation

224 Cr 35 4s

CrC) 34
3d 4s

6 NH3

donated e pavu from 6 NHa ligands XX. 2 3d,

44 0md 34p ovbitals oru owailabu to form 5 brid ovbta
follosin g d'sp3 kybridisakion whieh Can aceept 6 ebau. Ipain eaeh
fTom NH3 Ta eompound octokudral, +* 3 ba7amagnetie.
Spin only magnetic moment =
n (n+2) BM

IS BM

Co(JIL) 3d

CNstrong tield,paining
will taka place
breaung
Hund's Tulu

ed'sb3

6 CN

Diamagnetic ds3
Repelled by magutie
Octadral. field.

FeCc)7
Fe3t 38 5
35
45 4
Tatraudral. 4CI

4s
Sp3
 Hexa Tet raammin02ine (I) ion

24
2n (NH
2
90
2n 4s
2n 2+

N 2+
Ni2 3

d s , 4 CN
Squone ploman
Ligand field ot CNi t ong enoug to fore e tha es to
pail. Dia

vi(c),]
sh3 4CI
Pana V2(042) 3
8
reCmo
Fe 24 346
36

4s 4 4d

sp32

Sp32

F 3d

6 CN

Dia
(i(co) Oh

N
N
348 4s2 nar1] U

v 1
Sp3
Tetrahaonal
Dia
 4 19
M(ABCo))- 69uare planon, 3 yi4om one
only pos sibl e

A
M A
M
C D
D

Outline 4he synthesis of all the 3iomers of Pt ct(NHa)(NH, Me) Ne

-I
CIjI
NH3 C C
PE NO2
HgN HN

NH,Me

MeHN
PE

HoN NO2

2
NO NH3
C NO.
NHMe NH NO
PE
PE
Ct HgN CI H3N CI

MeNt2
CI NO
PE NO2
Pt
MeHN
2 Met,N C

NO MeNH2 HeR,N NO 2
PE

PE
C we pt NO
MeHN NH
HeR Ct NR3
T 4mth ot t 3 isomand ean be erplained by greater Tana

efec t NO2.
iseuohne weakness ot tu PhCI bond a companed to Pt - N bond
has been taksn into aonsideration,

MAG M Only one configuzakion

a
34

Mab
M
1

Ma4 Td Sq. planan

Only fom only I frm

Ma,b only oTm

2 isomers. cis
Mag be trons.
Mabcd
3 isomeTS.
ob
b
a
Mab2 a a
a a M
a o
 A Amilavypo of isamevicm oeeuu for Ha,bg typo oh ey, Sinee
each trio of similan igands can occapy eitheT adjotent posiH on at

th eons of on oolah1dy as fac ( foeiol type. 1oel) o positions

n
onound te meridian ot th octakudron.( mevidional type)

M
a

b
fac ial
meridional.

b b

4
N
-droy quionoline (oxine)
OH

At(owin) innn mat allie complux ot first kind