Research Project:
Organotin Compounds
Student name: Harry Chan
Student number: 971966620
Instructor: Professor M. Denk
Due date: April 12, 2000
The History of Organotin Compounds
E. Frankland discovered the first orgaontin compound in 1849. The first organotin
compound was diethyltin diiodide (Et2SnI2). From then on the research on organotin
chemistry has been conducted under this very day. The development of organotin
chemistry was very slowed in the first 50 years of its development, mainly because the
lack of effective and reliable methods to produce compounds1. 4 years after the discovery
of Et2SnI2, Frankland introduced diethyltin oxide, dichloride and an air-sensitive
diethyltin that when heated above 150oC deposited tin and produced tetraethyltin2. From
1850-1880, chemists such as Cahours, Riche, C.Lowig, A.Strecker, had all contributed to
the development of organotin compounds.
Around 1900, the development of organotin compounds had started to be in rapid
grown. The reason for such was the availability of organomagnesium halides as
alkylating and arylating agents3. The Grignard reagents was important in the development
of organotin compounds since its high electropositivity of Mg allows the transfer of
hydrocarbon radicals to most main group metal.
Large-scale application of organotin compounds occurred in the 1930’s. The work
by Yngve and Carbide and Carbon Chemical Corp. discovered one of the major use of
organotin compounds till this very day: the heat-stabilizing effect on PVC4. Such
discovery increased the pace of development of organotin compounds and attracted more
Sawyer, A. K., Organotin Compounds, volume 1, p.1. Marcel Dekker, Inc., (1971)
Neumann, W. P., The organic chemistry of tin, p.1. John Wiley & Sons Ltd., (1970)
3
Sawyer, A. K., Organotin Compounds, volume 1, p.1. Marcel Dekker, Inc., (1971)
4
Ibid, p. 2.
1
2
input in such research area. The demand of organotin compounds also increased from 50
tons in 1950, to 2000 tons in the 60’s, to 25,000 tons in 19755.
The analysis of Sn-H bond started in 1955 by Noltes provided more mechanistic
options such as additional reaction (or called hydrostannations) and catalytic
decomposition of Sn-H to produce Sn-Sn6.
R3SnH + CH2
CH - R'
R3Sn - CH2CH2R'
From the 1950’s to present day, the researches on organotin compounds had been one of
the mostly researched areas in organometallic chemistry. For example, the highly
reactivity of Sn-H bond, the production of C-Sn bond, organotin halides, Sn-N, Sn-O, SnP, Sn-S, SnSe, Sn-Te, and their physical properties such as IR spectroscopy, the 1H, 13C
NMR spectroscopy, the 119Sn Mossbauer spectroscopy.
The application of organotin compounds in the 60’s was mainly the stabilizer of
polyvinyl chloride (PVC). It was also involved in agriculture and biology. Nowadays
organotin compounds are also involved in biocidal activitiy and as anticancer reagent.
The new uses of organotin compounds will be discussed in the paper, also with their
toxicity and environmental impact.
5
Zuckerman, J. J., Organotin Compounds: New Chemistry and Applications, p.2. American Chemical
Society, (1976)
6
Sawyer, A. K., Organotin Compounds, volume 1, p.3. Marcel Dekker, Inc., (1971)
Structure of organotin compounds
Tetravalent compounds
Table 1. Bond distances (pm) for tetravalent organotin compounds
Compound
Me4Sn
Me3SnH
Me2SnH2
MeSnH3
SnH4
Me3SnCCH
Me3SnccSnMe3
(CH2=CH)4sn
(HCC)4Sn
(HCC)3SnI
(F3CCC)4Sn
Ph4Sn
Me3SnCl
Me2SnCl2
MeSnCl3
SnCl4
E-C
E-H or E-X
214.4
214.9
171
215.3
168
214.3
170
214.1(Me) and 212.6
171.1
212.7(Me) and 209.5
211.6
206.7
206
206
264.5
207
216.8
210.6
235.1
210.9
232.7
210.4
230.4
228.1
The bond length of tetravalent compounds is shown above. Molloy, Zuckerman and
Haaland obtained these data in gas-phrase7. The general trend in the bond length of
simple tetravalent compounds is that the E-C bond length decreases, as the R-group that
attaches to them becomes bigger. However, the decreased in bond length remains within
1 ppm.
Alkyls group with organotin compounds had shown some interesting study. For
example through the 158K X-ray study for Me4Sn suggested the molecule has a 3-fold
axis with 3 different Sn-C bond length: 213.8pm, 210.2pm, 214.4pm. The crystal
7
Patai, S., The chemistry of organic germanium, tin and lead compounds, p. 99. John Wiley & Sons Ltd.,
(1995)
structures of another alkynyl-tin compound Sn(C≡CR)
4
showed deviation from the
theoretical CSnC angle that would be between 207.4 – 207.9 pm8.
For aryls compounds, for example Ph4Sn in table 1, there was a sign of steric
effect based on the measured Sn-C length. The following table for Sn-C bond of
arylorganotin compounds showed the effect of steric.
Table 2. Average E-C bond lengths for Ar4E compounds by crystallographically9
E/Ar Ph o-Tol m-tol p-tol C6F5
Sn
214.3 215.2 215 214.7 212.6
Other aryl compounds such as Sn (p-C6H4Oet)
4
showed that the presence of the Oet
group twisted out of the plane and releases some of the steric strain. The center Sn
therefore had lost is symmetry but the structure is very close to tetrahedral. Analyzing the
triphenylvinyltin showed the presence of intramolecular steric pressures compound. The
Sn-C bonds are equal but with an average twist angle of 51.6o, which are 7o less than
SnPh410.
Rings containing 4-coordinate isolated Sn
The ring structure of 4-coordinate Sn compounds is divided into 4-ring, 6-ring, 7-ring, 8ring or even more complex. The bond length of a 6-ring compound SnBu2t had been
reported as followed:
Table 3: bond length for SnBu2t
SnR2
SnBu2t
Sn-C (pm)
219.4
Sn-O (pm)
196.5
CEC (degree)
119.5
OEO (degree)
106.9
8
Patai, S., The chemistry of organic germanium, tin and lead compounds, p. 99. John Wiley & Sons Ltd.,
(1995)
9
Ibid, p. 104.
10
Ibid, p. 105.
EOE (degree)
133.1
The four-ring structure is symmetrical in most cases. The [R2EY]2 ring is very common
for heavy Y group and bulky R. The structures of R2SnS, R2SnSe and R2SnTe were
determined as followed:
R
Y
Sn
a R
Sn b
Y
R
Y=
A=
B=
Aa =
Bb =
Aa’ =
a' R
S
243
221
86o
117o
94o
Se
255
218
83o
115o
98o
Te
276
220
80o
117o
100o
4-ring structures had also been determined:
Cl
Me
Sn
Sn
Me
Me2
Cl
Me
N
N
Cl
Sn
Me2
A = 215.6 – 217.9 pm
B = 208.8 – 212.2 pm
C = 212 pm
D = 255.7 – 261.5 pm
Dd = 162.4o – 165o
E = 313 pm
Sn
Cl
Me
Some more complex ring compounds have also been analyzed. For example, the 5membered ring SnOSnC=C, which obtained from the oxidation of Sn-Sn bond of the
SnSnCC ring11.
H
O
R2Sn
SnR2
Organotin compounds with coordination numbers above 4
The acceptor power decreases when the number of organic group that attached to tin
increases. The general geometry for coordination number 5 is trigonal bipyramidal
structure. The bond in the axial position in this case is mostly longer than the equatorial
bonds. The structure of tetraorgano compounds, triorgano compounds, diorgano
compounds, mono-organo compounds and polynuclear compounds have been analyzed.
The following structures are just some of them.
Me2HCC
Et
C
BEt2
Me
Sn
C
Me
C
CHMe2
tetraorgano compounds
11
Ibid, p.114.
R2
Sn
R
OH
O
R
Sn
Sn
RSn
RSn
Sn
O
R
Sn
R
Sn
R
RSn
SnR2
R2Sn
Sn
Sn
Sn
O
O
R
R
RSn
R
B
Ar
SnR
RSn
RSn
Sn
R
cluster structure for polynuclear
organotin compounds
Diorgano compounds
There are also some important structure determined in the 1980’s and 90’s. For example
the structure determination of organotin fluorides by Jagirdar et. al. Some of the
examples are the X-ray study of Me2Sn (F)CH2CH2P(O)Ph2 and (2-Carbomethoxy-1,4cyclohexadien-1-yl)dimethyltin fluoride.
H3C
F
F
O
Sn
O
P
H3C
Me2Sn(F)CH2CH2P(O)Ph2
Sn
O
CH3 CH3
Me2Sn(F)[2-C(O)OMe- 1,4 -Chd]
The X-ray structure of Me2Sn(F)CH2CH2P(O)Ph2 suggested that the pentacoordination
around tin resulted a distorted trigonal bipyramidal geometry. The Me2Sn(F)[2-
C(O)OMe-1,4-cyclohexadienyl is the first hexacoordinated triorganotin compound that
has a Sn-O bond. There is the distortion of the trigonal bipyramidal due toe the
nucleophilic attack of the C=O to fluorine, resulting the extended feature of tetrahedron
around the tin. Beside there is an intermolecular nucleophilic attack of the F atoms to the
cyclohexadienyl group, resulted the distortion of octahedra arrangement of the bonding12.
Another important structure was the diorganotin difluorides, R2SnF2. The
vibrational and
119
Sn Mossbauer spectra suggested that the Sn in the hexacoordinated
arrangement has a linear C-Sn-C group13. Diorganotin difluorides has the tendency to
from polymeric structures due to the intermolecular attraction. The coordination number
for increases from 4 to 6 due to Lewis acidity. The compound Me2SnF2 form a sheets of
Sn and F atoms, and every tin atom is bridged to the 4 neighbors by the existence of
disposed F atom14.
H3C
CH3
Sn
Sn
F
H3C
CH3
F
F
Sn
CH3
Sn
F
H3C
CH3
CH3
Sn
H3C
CH3
molecular structure of Me2SnF2
12
Jagidar, Murphy and Roesky, Progress in inorganic chemistry, 48, 414-415 (1999)
Ibid, p. 418
14
Ibid, p. 419
13
Physical and Spectroscopic Properties
IR spectroscopy
Infrared spectroscopy has been widely use in the structure determination of
orgaontin compounds. Group frequencies are easy to identify for organotin compounds.
The reason being that tin atom has a large mass, and the internal vibrations of organic
groups that are attached to the tin atom are distinct from each other. The atoms that are
connected directly to the tin atom provide the frequencies of skeletal vibrations for
structural analysis. The Sn-C stretching provides important information about the
structure, and it depends on the organic group that is attached to the Sn. The Sn-C
stretching also influence by the coordination number of the Sn atom15.
Sn-H stretching vibration also provided information about the structure of
organotin compounds. The Sn-H stretching vibration will be higher if there is the
presence of electronegative group attached to the Sn atom, with H attached to Sn atom.
Sn-O vibration had a range of 300-800 cm-116.
The following are the tables for some of the IR stretching measurement for
different organo tin compounds:
Compound
4 Sn-C bond
Me4Sn
Et4Sn
Pr4Sn
Bu4Sn
Me3SnCCH
State
Liquid
Liquid
Liquid
sol in CS2
Liquid
3 Sn-C bond
Me3SnCl
sol in cyclohex.
Me3SnBr
sol in cyclohex.
Me3SnI
sol in cyclohex.
15
16
v(Sn-C) (cm-1) Compound
2 Sn-C bond
528 Me2SnCl2
508s
Me2SnI2
590s,500s
Et2SnCl2
592s, 503s
Et2SnI2
538vs, 517w
Bu2SnCl2
Bu2SnI2
542s, 513w
539s, 511m
536m, 508w
State
v(Sn-C) (cm-1)
sol in CS2
sol in cyclohex.
sol in CS2
sol in benzene
sol in CS2
sol in benzene
560, 524
542m, 511w
531, 497
520m, 490m
602, 517
592m, 508m
1Sn-C bond
MeSnCl3
soln
MeSnI3
sol in cyclohex.
551-546w-m
527w
Sawyer, A. K., Organotin Compounds, volume 3, p.999. Marcel Dekker, Inc., (1971)
Ibid, p. 1001.
Me3SnOH
Et3SnI
Et3SnOH
Bu3SnCl
Bu3SnBr
Bu3SnI
solid
sol in cyclohex.
solid
liquid
sol in cyclohex.
sol in cyclohex.
540s
506m, 482w
510vs, 485m
601s, 513m
599s, 503m
598s, 501s
EtSnCl3
BuSnCl3
sol in benzene
liquid
522w
596, 518
NMR spectroscopy
There are in total 10 stable isotopes for tin and 3 of them have non-zero magnetic
moments and a nuclear spin I = ½. They are
115
115
Sn,
117
Sn and
119
Sn. The abundance of
Sn is too low for any practical use. The 117Sn and 119Sn provide complex NMR spectra
since both of the isotopes are couple with –CH and –CH. The chemical shift s in the
117
Sn and
119
Sn spectra can be as much as 1800ppm. The direct spin-spin coupling
constants have the magnitude of 2000cps whereas the indirect spin-spin coupling
constants only have a magnitude of 50-100cps. The following are the tables of NMR
measurement for different organotin compounds.
Formula
organotin and organotin halides
Me3SnMe
Me3SnEt
Me3SnPr
Me3SnBu
Me3SntBu
Me3SnCH2Ph
Me3SnPh
T
9.93-9.96
9.97-9.95
9.96-9.93
9.97-9.92
9.99-9.97
9.98
9.73
Me4Sn
Me3SnEt
Me3SnBu
MeSnEt3
Et4Sn
PhSnMe3
PhSnEt3
Ph3SnEt
Me3SnCl
(M3CH2)SnCl
(ClCH2)3SnCl
J117/119(Sn-Me)
J117/119(Sn-Et)
51.5-52.0/54.3-54.4
49.9-50.2/52.2-52.6
50.0-50.2/52.3-52.5
49.9-47.9/49.7
47.5-47.9/49.7-50.2
50.8/52.9
52.2/54.6
52.0/54.3
50.5/52.8
50.4/52.6
47.1/49.3
74.4/77.9
68.6/72.0
65.7/69.2
52.9/55.2
70.5/74.0
79.7/83.2
9.34-9.37
8.64
6.31
56.0/58.5
38.7
18.3
Me3SnBr
(M3CH2)SnBr
Me2SnCl2
9.2
8.61
8.84
organotin hydrides
T
Me3SnH
Et3SnH
Pr3SnH
Bu3SnH
Ph3SnH
Me2SnH2
Et2SnH2
Pr2SnH2
Bu2SnH2
Ph2SnH2
MeSnH3
5.27
5.00-5.24
5.21
5.22
3.03,3.16
5.55
5.25
5.42
5.43
3.98
5.86
56
37.5
66.6/69.7
J117/119(Sn-H)
1664/1744
1539/1611
1533/1605
1532/1609
1850/1935
1717/1797
1616/1691
1615/1685
1619/1690
1842/1927
1770/1852
Synthesis of organotin compounds
Sn-C bond
The reaction between tin and organic halide is the most general method to
produce a Sn-C bond:
2R-X + Sn  R2SnX2
Alkyl halides are also used to synthesis the Sn-C bond. The reactivities of alkyl halides
decreases in the order of: RI> RBr> RCl and MeX> EtX> PrX17. Example of the use of
OH2
(PhCH2)3SnCl
PhCH2Cl
+
Sn
toluene
(PhCH2)2SnCl2
alkyl halides is as follow:
No information on the price or hazard of this reaction.
Diorganotin halides can be obtained by reacting tin, HCl, and a , -unsaturated dihalide
(1). Alkyltin trihalide can be obtained by reacting tin halides with alkyl halides (2).
Sn
+
2HCl
+
2 H2CCHY
Cl2Sn(CH2CH2 Y)2
(1)
Y = CO2R, COR, CONR2, or CN
RBr
17
+
SnBr2
Et3Sb
RSnBr3
(2)
King, R. B., Encyclopedia of Inorganic Chemistry, volume 8, p. 4173. John Wiley & Sons Ltd., (1994)
The price for Sn powder is about $70.70 per 250g. For HCl, each 100mL costs about
$48.90. However the price for H2CCHCN and the rest are unknown, the cost of the
reaction cannot be calculated.
The synthesis of Sn-C can also be obtained from Sn(IV) halides. The use of more
electropositive metals is important in such reaction (3).
R4-nSnXn + nR'-M
R4-nSnR'n
(3)
No information on the price or hazard of this reaction
The addition of organotin hydrides to alkenes and alkynes can also synthesize the Sn-C
R3SnH +
R3Sn
(4)
R3SnH +
R3Sn
bond (4).
No information on the price or hazard of this reaction
H
Distannanes
R3SnX
2 R 3SnH
Mo
-H2
cat.
(5)
R3Sn
SnR3
R3SnX + R3SnM
R 3SnH + R3SnNR'2
The general method to produce distannanes is as followed:
Linear Polystannanes
The synthesis of tristannanes and tetrastannanes can be achieved by the
hydrostannolysis reaction of diorganotin dihydrides and 1,1,2,2-tetraorganodistannes18
(6).
2 R'3Sn-NMe2 + H-(R2Sn)n-H
R'3Sn-(R2Sn)n-SnR'3
(6)
No information on the price or hazard of this reaction
The reaction of triorganotin anions with diorganotin dihalide can also synthesize
linear polystannanes (7). On the similar basis, tetraorganotin can also be produce by
reacting diorganotin dihalide with 1,2-diiodo-1, 1, 2, 2-tetra (t-butyl) distannane (8).
2Ph3SnLi + I-(But2Sn)-I
18
Ph3Sn-(SnBut2)-SnPh3
(7)
Sita, L. R., Advances in organometallic chemistry, 38, 205 (1995)
2 Ph3SnLi
+
I-(But2Sn)2-I
Ph3Sn-(SnBut2)2-SnPh3
(8)
Branched Polystannanes
The reaction of Ph3SnLi and SnCl4 produced (Ph3Sn)3, which is the first synthesis
of branched polystannanes19(9). The synthesis of branched polystannanes can also be
achieved by hydrostannolysis reaction of organotintrihydrides and (dimethylamino)
trimethylstannane (10).
Ph3SnLi + SnCl4
(Ph3Sn)3Sn
RSnH3 + 3 Me2N-SnMe3
(9)
(Me3Sn)3SnR
(10)
R= Me, Et, Bu, But, Ph
SnCl4 is a toxic compound. It is toxic by inhalation, upon contact with skin or swallowed.
The compound is either in a white or yellow form. The LD50 for the compound is
120mg/kg by IPR-RAT.
Cyclopolystannanes
Sakurai and co-workers have achieved the synthesis of monomeric divalent
diorganotin compounds just recently. The compound had been shown that it is
monomeric in solution and in solid states20.
TMS
TMS
Sn
19
20
Ibid, p. 215
Ibid, p. 217
TMS
TMS
The following are other methods of synthesizing cyclopolystannanes compounds.
TMS
TMS
Li
. SnCl4
Li
Sn
TMS
R2SnCl2
+
TMS
ButMgBr
R2Sn
SnR2
R2Sn
RLi
+
SnCl2
Et2O
n
SnR2
R2
Sn
X
-78oc R Sn
2
Sn
R
Sn
R2
No information on the price or hazard of these reactions
SnCl2 * 2 H20 + 2 (CH3CO)2O
SnCl2 + 4 CH3CO2H
(11)
Synthesis of SnCl2
226g of tin(II) chloride dihydrate was added to 204g of acetic anhyride21.
No information on the price or hazard of these reactions
21
Herrmann, W. A., Synthetic methods of Organometallic and Inorganic Chemistry, volume 2, p. 271.
Geory Thieme Verlag, (1996)
Application of organotin compounds
PVC stabilizers
During the synthesis of PVC, the temperature will reach up to 180-200oC. At this
temperature PVC started to decompose. The decomposition is evident by the
discoloration of the compound, from yellow to brown and at the end to black 22. The use
of a stabilizer is require in order to prevent such decomposition of occurring and
organotin compounds are good stabilizers in this case. Diorganotin and triorganotin
thiolates and carboxylates are the mostly used organotin as stabilizers. The
decomposition occurs when there is a loss of HCl. The loss of HCl resulted in
decomposition and discoloration. The addition of organotin compounds will inhibit the
evolution of HCl gas. The addition of Sn-C bond to PVC has anionic exchange with the
chloride in the polymer and therefore provides a stable mixture.
Catalytic Applications
Dialkyltin dicarboxylates are used as catalysts for polyurethane foam formation.
Monobutyltins have been used as catalysts for transesterification and esterifications.
Biocidal Applications
Fungal control –One of the major uses of organotin compounds is as the
antifungal agents. The first compound that was used as antifungal agent was triphenyltin
acetate. In trialkyl tin compounds, tirmethyltin compounds are the most toxic to
mammals and insects. Triethyltin compounds are most toxic to mammals; tripropyltins is
22
Sawyer, A. K., Organotin Compounds, volume 3, p.933. Marcel Dekker, Inc., (1971)
most toxic to Gram-negative bacteria; and tributyltin compounds are most toxic to Gramnegative bacteria and fungi23. The diseases that such compounds attacked are late blight
in potatoes, leaf spot in sugar beets and leaf spot in celeriac24.
Intestinal worms removal for chickens – dibutyltin dilaurate had been used as
anthelmintic. For example a drug named Wormal which contains piperazine,
phenothiazine, and dibutyltin dilaurate was used for such purpose.
Industrial uses
Wood preservation – since organotin compounds are antifungal agents, they
were also being used in wood preservation process. Both triethyl and tributyltin
compounds are used. A higher concentration of organotin compounds can even prevent
the attack by insects25.
Slime control in paper mills – papermaking involves the use of large quantity of
water. The nutrients content for the water favors the growth of microorganisms. In this
case slime is formed. Tributyltin oxide was added to slime in order to eliminate such
compounds26.
Protection of Cables from rodent attack – experiments had shown that
organotin compounds, tributyltin chloride in this case, can be an effective rodent repellent
in the 70’s. The R50 of triphenyltin chloride for mice was 6.9 mg/cm2 27.
23
King R. B., Encyclopedia of Inorganic Chemistry, volume 8, p.4194. John Wiley & Sons Ltd., (1994)
Sawyer, A. K., Organotin Compounds, volume 3, p.953. Marcel Dekker, Inc., (1971)
25
Ibid, p. 955.
26
Ibid, p. 957
24
Latest Uses of organotin compounds
One of the latest use of organotin compounds was the use of labelled tin compounds in
reactions. There are 2 types of tin compounds that are isotopically labelled and
synthesized. The first type was prepared by using specific isotopes of tin. The isotope in a
group bonded to the tin atom prepared the second type. The details of these reactions will
not be discussed in this research. The major use of these labelled tin compounds was to
labelled substrate during reduction reactions.
Computational Methods28
The computation chemistry for heavy main group elements had been made
possible by the ab initio program. Such program allows one to deal with the large number
of electrons of heavier element such as tin. The improvement of pseudo-potential
methods also improves the calculation of heavy elements become less time consuming.
The structure analysis of organotin compounds relies heavily on the use of X-ray
spectroscopy. For example, the structure determination in the journal by Jagirdar et. al.
are conducted by the use of X-ray diffraction and X-ray crystallography. Beside the use
of solid state 119Sn NMR also involved in such analysis.
27
Ibid, p. 960
Patai, S., The chemistry of organic germanium, tin and lead compounds, p. 587-593. John Wiley & Sons
Ltd., (1995)
28
Library Resources
The most useful book in the research project is The chemistry of organic
germanium, tin and lead compounds. This book provided the most useful information
about the topic, at the same time this book is the latest among all books. The Organotin
Compounds series by Sawyer provided most of the background information about the
topic, but the series was out of dated. Most of the resources that were used in this project
were from the Chemistry Library. The books that were recommended are not sufficient to
provide all the information for this project. The monthly journal Advances in
organometallic chemistry and Progress in inorganic chemistry are essential because they
had provided the latest direction and discovery for the topic.
References
1. Dickerson, A.F., Comprehensive Inorganic Chemistry, volume 2, 1st edition.
Trotman: (1993), Great Britain.
2. Baines, K.M. and Stibbs, W.G., Advance in organometallic chemistry, 37, 304 (1996)
3. Herrmann, W. A., Synthetic Methods of Organometallic and Inorganic Chemistry,
volume 2, Geory Thieme Verlag: (1996), Germany.
4. Jagirdar, Murphy and Roesky, Progress in inorganic chemistry, 48, 404, John Wiley
& Sons: (1999), United States.
5. King, R. B., Encyclopedia of Inorganic Chemistry, volume 8, p. 4172-4195, John
Wiley & Sons Ltd. : (1994), Great Britain.
6. Neumann, W. P., The organic chemistry of tin, John Wiley & Sons Ltd., (1970),
England.
7. Patai, S., The chemistry of organic germanium, tin and lead compounds, John Wiley
& Sons Ltd., (1995), Great Britain.
8. Poller, R.C., The chemistry of organotin compounds, Logos Press Limited, (1970),
Great Britain.
9. Sawyer, A. K., Organotin Compounds, volume 1, Marcel Dekker, inc., (1971), New
York.
10. Sawyer, A. K., Organotin Compounds, volume 2, Marcel Dekker, inc., (1971), New
York.
11. Sawyer, A. K., Organotin Compounds, volume 3, Marcel Dekker, inc., (1971), New
York.
12. Sekiguchi, A. and Sakurai, H., Advances in organometallic chemistry, 37, 18,
Academic Press Inc., (1995), United States.
13. Sita, L. R., Advances in organometallic chemistry, 38, 189, Academic Press Inc.,
(1995), United States
14. Zuckerman, J. J., Organotin Compounds: New Chemistry and Applications, American
Chemical Society: (1976), United States