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Reaction of stannic chloride with hydrazine
J. Iaorg. NucLChem., 1966.VoL 28. pp. 161 to 165. PergamonPress Ltd. Printedin NorthernIreland
REACTION
OF STANNIC
CHLORIDE
WITH
HYDRAZINE
R. C. AGGARWAL and R. C. MAKHIJA Chemistry Department, Lucknow University, Lucknow, India (Received 21 December 1964) AImtract--Dilute chloroform solutions of stannic chloride and anhydrous hydrazine react to form products of empirical compositions, SnClt.NtHs (I), SnCI¢2N2H, (ll), SnC14"3NtI-~ (Ill) and SnCl¢4NsI-I4 (IV). Of these products only I is a pure compound, the others being mixtut~ of trichloromonohydrazimv--stannane or its hydrazine adducts with hydrazine hydrochloride. Repeated extraction of these with anhydrous hydrazine yields a dark polymeric solid, SnN,I-I4 (V). On refluxing I with chloroform solutions of hydrazine, pyridine or ~-picoline, adducts SnCls'NtHs'2N2H~ (VI), SnC18.NtHs.2C6I-I6N (VII) and SnCIs.NtHs.C6I-I~(CHs)N (VIII) respectively are produced. Intcrconversion and thormal decomposition of some of these compounds have been studied and their infra-red spectra measured. Possible mechanisms of their formation are given.
IN previous communications the reactions of hydrazine with SiF4<1~ and GeF4, ¢a~ and of phenylhydrazine~3~with SnC14 and SnF 4 have been investigated. In the present paper the results of our investigations on the reactions of stannic chloride with hydrazinc are presented. DISCUSSION
That substitution reactions occur in the stannic chloride-hydrazine system is evident from (i) the evolution of gaseous hydrogen chloride observed during the course of these reactions, (ii) the presence of hydrazine hydrochloride in the reaction products, II, III and IV as shown by their infra-red spectra and extractions with hydrazine and (iii) the isolation of I and V from stannic chloride hydrazine reactions. The occurrence of substitution reactions in the above system is strongly supported by the condensation reactions reportedly undergone by many anhydrous chlorides with ammonia, ~4~hydrazine(6) and primary and secondary amines. ~s~ The hydrazinolysis of stannic chloride seems to increase with time, temperature and concentration of hydrazinc. Extensive hydrazinolysis is often marked with the formation of dark polymeric material. Interaction of stannic chloride and hydrazine in chloroform at low temperatures (0°C) and at low concentrations of hydrazine (up to molar ratio 1 : I) produces an unstable solid compound, probably a 1 : 1 adduct, which loses hydrogen chloride at n~ R. C. AOa~WXL and M. OW~SZCHUK,Canad..i.. Chem. 41, 876 (1963). ,27 R. C. AGGARWALand M. ONYSZCH~, Pros. Chem. Soc. p. 20 (1962). ~a~R. C. A6OARWALand R. C. MAKHUA,Z. Anorg. Chem. 336, 81 (1965). c,~ E. BANsm'rva~and G. W. A. FowL, s, J. Chem. Soc. 751 (1958). ~'~ W. G. PATEnSONand M. ONYSZCHUK,Canad. J. Chem. 41, 1872 (1963). ~'~ G. W. A. FOWLES and C. M. PLY.ASS,Y. Chem. Soc. 1674 (1957) G. W. A. FOWL~ and C. M. PLEASS,J. Chem. Soc. 2078 (1957). 11 161
162
R . C . AGGARWALand R. C. MAKI-HJA
room temperature to form the stable compound I. As the concentration of hydrazine relative to stannic chloride is increased, products II, III and IV are formed. The hydrogen chloride liberated during hydrazinolysis reacts with the tmreacted hydrazine forming hydrazine hydrochloride. The following mechanism, based on the similar work of BANNISTERand FOWLES,~7~can easily explain the stepwise formation of the reaction products from I to IV.
SnCI~ + NsH4
/
SnCla.N2Hs. + HCl
i
> SnCI4"N2H~ +N2Ha I :1 adduct NN,4 SnCIs-N~H8 + N~HsCI n
II
•
I+NzH. SnCI,'N2Hs'N2H4 -'1-N~HsCl
I
NjH. I i I
SnCIs'N2Hs-2N~H. -'1-NsHsCI
The overall reaction with excess of hydrazine is then :-SnCI4 + 4N~H~
• SnCIs.NsH3-2N~H4+ N~HsCl
(i)
Not more than one Sn-C1 bond seems to be hydrazinolysed in reactions of stannic chloride and hydrazine up to the molar ratio, 1 : 8, studied. If dichloro-dihydrazinostannane, SnCI~(N2Hs)~ is assumed to be formed for a moment then the overall reaction with excess of hydrazine would be expected to take place in the molar ratio 1 : 6 as given below :-SnCI4 + 6NzH4
). SnCls(NiHs)l.2NiH ~ + 2N2HbCl
rather than in the molar ratio l : 4 experimentally obtained. The alternative mechanism for the experimentally observed 1:4 reaction, SnCI, + 4N~H4
~ SnCl2(N2Na)2 + 2NsHrCI
cannot, however, explain a number of our experimental results and is therefore ruled out. The results of thermal decomposition show that IV liberated hydrazine loosely bound to I and this further supports the above mechanism. Hydrazine co-ordinatively bound to I, a poor Lewis acid, would be expected to be lost readily on heating. That I has acceptor properties was established by the preparation of the adduets, VI to VIII by its reactions with hydrazine, pyridine and ~-picoline. The fact that we have been able to prepare the compounds I and VI assumed to be formed in stannic chloride hydrazine reactions conclusively proves the correctness of the mechanism proposed. The results of the interconversions can be explained on the basis of the mechanism proposed above for the stannic chloride hydrazine reactions. When stannic chloride is reacted with excess of hydrazine in the pure state or when the products I to IV are repeatedly washed with anhydrous hydrazine, all the Sn-C1 ~ E. BANNISTERand G. W. A. FOWLES,.!., Chem. Soc. 310-315 (1959).
Reaction of stannic chloride with hydrazine
163
bonds appear to be hydrazinolysed and the polymer V presumably results through the formation of the unstable tetrahydrazinostannane, Sn(N~Ha) v as follows : - SnCl~ -F N,,H,
)' SnCIs'N=Hs -k HCI +
N=H,
N=H¢
SnCl=(N=H~)= + HCI q- N=H~ SnCII ,IsH~)a -k HCI
N=H, X'~4N=H6CI N=H, ~ l
-k NsH, Sn(N~ -Is)~ ÷ HCI
N=H4
l
SnNcN~H 8 + 2N=H4
Similar mechanisms were put forward by PATERSON and OIqYSZCHUK(5) to explain the formation of the boron and aluminium polymers from reactions of hydrazine with the trichlorides of boron and aluminium. As the 1 : 1 and 1 : 2 adducts of trichloromonohydrazino-stannane are insoluble in organic solvents, little information about their structure could be obtained. The 1:2 adducts, SnCIa-N~Ha.2N~H4 and SnCla'N~Ha'2CsHsN are certainly octahedral. The 1 : 1 adduct SnCla.N2Ha CeH4(CHa)N appears to be polymeric and is also probably octahedral through chlorine bridged structure, ts~ The infra-red spectra of compounds I to VI and hydrazine have been recorded; the frequency assignments are given in Table 1. These were made by comparison of these spectra with those of hydrazine c9~and hydrazine monohydrochloride, tx°~ Further the known assignments of the spectra, BFs.NzHI, m) B(CHs)a.N2H4(IS) SiF4.2NsHI (1~ and GeF4.2NsH4 tla~ have been kept in view while interpretating our spectra. EXPERIMENTAL Stannic chloride (B.D.H.) was purified as described by HILDEBRANDand CAR~. aS~ Anhydrous hydrazine was prepared by refluxing 95 q- ~o material (Eastman Kodak) for 3--4 hr over potassium hydroxide pallets and was then distilled. The fraction boiling in the range 111-113° was found to be 100 per cent pure by the iodate method. ~m The solvents (chloroform, ether) were purified by standard methods. The purified reagents were stored in a dry box of low humidity. Infra-red spectral measurements were made in the frequency range 400(b-650 cm-1 using a PerkinElmer Infra-red cord equipped with sodium chloride optics. Samples were examined in nujol mulls and KBr. ~s~E. L. Mtm'rl~ltT~S, J. Amer. Chem. Soc. 82, 1082 (1960). ~'~J. GOUBEAUand E. RICKER,Z. Anorg. chem. 310, 123 (1961); P. A. GIGUERAand I. D. LrU., J. Chem. Phys. 20, 136 (1952). tx0~j. C. DEcros and D. P. PEARSONJ. Amer. Chem. Soc. 75, 2436 (1953). m~ W. G. PA'na~SONand M. ONYSZCHUK,Canad. J. Chem. 39, 986 (1961). cm W. G. PATERSONand M. ONYSZCnUK,Canad. J. Chem. 39, 2324 (1961).
~a~ R. C. AOOAgWALand M. ONYSZCmJK,Unpublished work (1961). tx,~ T. L. BROWNand M. KoBtrrA, J. Amer. Chem. Soc. 83, 4175-77 (1961). ~m j. H. I-IF.~EegANOand J. M. CARTER,Jr. Amer. Chem. Soc. 54, 3594 (1932). ~e~ L. F. AuDpa~-I and B. A. 0 ~ , The Chemistry of Hydrazine. Wiley, New York (1951).
R. C. AGGARWAL and R. C. MAKHUA
164
TABLE 1.----COMPARISON OF INFRA-RED SPECTRA AND AssIGNMENTS SnCI3.N2H8
3225 sh 3075 m
- -
2855 s -- -
- -
SnCIc4N,H4 SnCIs'NsHs-2NaH4
N2I-I4
Assignments
3178 m 3075 m
3283 sh 3075 s
3310 s 3190 s
N - - H stretching
-2855 s -2699 sh 2566 m
--2742 w
2920 m ---
unidentified Nujol
1600 sh
--
--
--
--
NH8 + stretching
--
--
1640 s
1574 s
1590 w
1590 m
1600 s
--NH~ and N H , + deformation (asym)
1560 sh 1502 m
1550 w 1491 m
-1491 s
---
- N H s and NHs + deformation
1448 s
1448 s 1398 s 1360m
-1406 w --
--
(sym) 1360s
--
1243 m
--
- -
l
- -
1055 s 945 s 940 s
l
1
3
s
1086 s 970 s 961 s 945 w
1080 s 945 m
- -
Nujol NHs + bending
Nujol 1330 s 1300 s --
NHs rocking (asym & sym) NII,+ bending
- -
1120-1020 sh 890 s
N H , wagging N - - N stretching
Note: (i) A s Sn-CI and Sn-N cm stretching vibrations occur beyond the range of our instrument no
information on these bands is presented in this table. (ii) s = strong, m = medium, w = weak, b = broad, sh = shoulder, asym = asymmetric and sym = symmetric Preparation and analysis o f compounds
Products II to IV were prepared by reaction (in dilute chloroform solutions) of stannic chloride and hydrazine in different molar proportions. Addition compounds of I were prepared by refluxing about 5 mmoles of this materialwith about 20 mmoles of hydrazine, pyridine, ~-picoline and quinolin¢ in about 100 ml chloroform for about 24 hr. The products were filtered, washed thoroughly with chloroform and dried. The compounds were analysed for tin, hydrazine and chlorine. Tin was estimated as SnOs, chlorine as AgC1 and hydrazine by the iodate m e t h o d : TM Results of analysis are summarized in the Tables 2 and 3. lnterconversions
II and III (about 2 mmoles) were refluxed with hydrazine (3-4 mmoles) in 100 ml of dry chloroform for 4--6 hr. The reaction products were filtered, washed and analysed. The results of analysis show that they were completely converted to IV. (Found: NsN,, 32.3. Calc. for SnClc4N,H~: NsI~, 32.9%.) When II, HI and IV were similarly refluxed with excess of stanic chloride in chloroform for 8 to 10 hr, they were almost completely changed into I. (Found: N2I-I4, 11.2; Sn, 46-1; C1, 44-7; Calc; for SnCIa'NjHs: NsI-~, 12"1; Sn, 46.4; C1,41.5~o.)
Reaction of stannic chloride with hydrazine
165
TAnLE 2.--AN~LYSXS OF TIN ( i V ) CHLORIDE-HYDRAZINE REACTION PRODUCTS Molar Ratio SnCI~: N~H, taken for reaction
Composition of compounds formed
N~H4
Sn
N,H4
Sn
4:1 1:1 1:2 1:3 1:4 1:8
SnCla'NiHa SnCls'NiHs SnC1,.2NsI-I~ SnCI4.3NsH4 SnC14.4NsH4 SnCI4.4N2H4
12"8 12"6 20.7 27.5 32.9 32-4
45"7 45.9 37.2 32-9 30.7 30.9
12"1 12-1 19.7 26.9 32.9 32.9
46"0 46.0 36-7 33-3 30.5 30.5
Calculated ~o
Found (%)
TABLE 3.--ANALYSIS OF ADDUCT$ OF TRICHLOROMONOHYDRAZINO-$TANNANE
Molar ratio SnCls'NsHa and base taken for reaction
Molar ratio 8nCls'N=Ha & base formed in adducts
NsH4
Sn
CI
N2H4
Sn
CI
SnCIa'NsHs:2NsH4 SnCIs-NIH8: 4CsI-~N SnCIa-NIHs :4C6H,(CHs)N *SnCls'NsHa :4CgHTN
1:2 1:2 1:1 1:0
29.9 9.6 9.2 12.8
36.7 28.4 32.5 45.5
32"1 ----
29.7 8.0 8-8 12"1
37"1 28-6 33-9 46.0
33"2 ----
Found (%)
Calculated (~o)
* Quinoline failed to form an adduct with 1 presumably because of steric considerations.
Reaction with concentrated hydrochloric acid When I, II, HI and IV were refluxed with concentrated hydrochloric acid, a clear solution was obtained which on cooling deposited, white crystals of hydrazine dihydrochloride, melting point 198°C. The filtrate contained Sn(IV). A typical reaction is given below:--
SnCI4-4N2H4 + 10HCI = H~[SnCI6] -{- 4NsHeCI 2
Thermal decomposition That SnC1,.4N2H~ loses hydrazine gradually when heated in a vacuum above 100°C was verified by condensing the volatile material and analysing it. IVwas heated in a vacuum ( < 5 mm) at a constant temperature for several hours till the analysis of hydrazine in the residue became almost constant. The temperature was then raised by about 20°C and the process repeated. Measurements were made in the temperature range 80-200°C and it was found that the fiberation of hydrazine increases linearly with temperature. At 170°C the hydrazine in the residue corresponded to SnCls-NgHs. Further, a white sublimate of ammonium chloride and uncondensable gases were obtained around this temperature. These observations indicate the following mode of decomposition at 170°C.
2SnCI,.4N2H~
• 2SnCls'NzHa + 5N2 -I- 9H~ + 2NH4CI
The residue at 210°C did not contain any hydrazine but gave tests for tin, NI-I4+ and CI-. This, when heated at about 300-400°C, yielded a white water soluble sublimate of ammonium hexachlorostannate. (Found: Sn, 34.0. Calc. for (NI-~BSnCI6; Sn, 32.2%.) The black nonvolatile residue left in the flask gave tests for tin, and nitrogen. The observed results at 300-400°C can be explained on the basis of the following mode of thermal decomposition.
2SnCI~'4NsH4
> SnN2 + (NH~)s[SnCI6] + 2NH4CI -I- SN2 -f- 8Ns
Acknowledgement The author's grateful acknowledgements are due to the Council of Scientific and Industrial Research, New Delhi (India) for the award of Junior Research Fellowship to one of them (RCM). The authors are also thankful to the Head of the Chemistry Department for providing the laboratory facilities and to Dr. M. ONYSZCHUK, McGill University, Montreal for his kind help in the form of chemicals and equipment.
REACTION
OF STANNIC
CHLORIDE
WITH
HYDRAZINE
R. C. AGGARWAL and R. C. MAKHIJA Chemistry Department, Lucknow University, Lucknow, India (Received 21 December 1964) AImtract--Dilute chloroform solutions of stannic chloride and anhydrous hydrazine react to form products of empirical compositions, SnClt.NtHs (I), SnCI¢2N2H, (ll), SnC14"3NtI-~ (Ill) and SnCl¢4NsI-I4 (IV). Of these products only I is a pure compound, the others being mixtut~ of trichloromonohydrazimv--stannane or its hydrazine adducts with hydrazine hydrochloride. Repeated extraction of these with anhydrous hydrazine yields a dark polymeric solid, SnN,I-I4 (V). On refluxing I with chloroform solutions of hydrazine, pyridine or ~-picoline, adducts SnCls'NtHs'2N2H~ (VI), SnC18.NtHs.2C6I-I6N (VII) and SnCIs.NtHs.C6I-I~(CHs)N (VIII) respectively are produced. Intcrconversion and thormal decomposition of some of these compounds have been studied and their infra-red spectra measured. Possible mechanisms of their formation are given.
IN previous communications the reactions of hydrazine with SiF4<1~ and GeF4, ¢a~ and of phenylhydrazine~3~with SnC14 and SnF 4 have been investigated. In the present paper the results of our investigations on the reactions of stannic chloride with hydrazinc are presented. DISCUSSION
That substitution reactions occur in the stannic chloride-hydrazine system is evident from (i) the evolution of gaseous hydrogen chloride observed during the course of these reactions, (ii) the presence of hydrazine hydrochloride in the reaction products, II, III and IV as shown by their infra-red spectra and extractions with hydrazine and (iii) the isolation of I and V from stannic chloride hydrazine reactions. The occurrence of substitution reactions in the above system is strongly supported by the condensation reactions reportedly undergone by many anhydrous chlorides with ammonia, ~4~hydrazine(6) and primary and secondary amines. ~s~ The hydrazinolysis of stannic chloride seems to increase with time, temperature and concentration of hydrazinc. Extensive hydrazinolysis is often marked with the formation of dark polymeric material. Interaction of stannic chloride and hydrazine in chloroform at low temperatures (0°C) and at low concentrations of hydrazine (up to molar ratio 1 : I) produces an unstable solid compound, probably a 1 : 1 adduct, which loses hydrogen chloride at n~ R. C. AOa~WXL and M. OW~SZCHUK,Canad..i.. Chem. 41, 876 (1963). ,27 R. C. AGGARWALand M. ONYSZCH~, Pros. Chem. Soc. p. 20 (1962). ~a~R. C. A6OARWALand R. C. MAKHUA,Z. Anorg. Chem. 336, 81 (1965). c,~ E. BANsm'rva~and G. W. A. FowL, s, J. Chem. Soc. 751 (1958). ~'~ W. G. PATEnSONand M. ONYSZCHUK,Canad. J. Chem. 41, 1872 (1963). ~'~ G. W. A. FOWLES and C. M. PLY.ASS,Y. Chem. Soc. 1674 (1957) G. W. A. FOWL~ and C. M. PLEASS,J. Chem. Soc. 2078 (1957). 11 161
162
R . C . AGGARWALand R. C. MAKI-HJA
room temperature to form the stable compound I. As the concentration of hydrazine relative to stannic chloride is increased, products II, III and IV are formed. The hydrogen chloride liberated during hydrazinolysis reacts with the tmreacted hydrazine forming hydrazine hydrochloride. The following mechanism, based on the similar work of BANNISTERand FOWLES,~7~can easily explain the stepwise formation of the reaction products from I to IV.
SnCI~ + NsH4
/
SnCla.N2Hs. + HCl
i
> SnCI4"N2H~ +N2Ha I :1 adduct NN,4 SnCIs-N~H8 + N~HsCI n
II
•
I+NzH. SnCI,'N2Hs'N2H4 -'1-N~HsCl
I
NjH. I i I
SnCIs'N2Hs-2N~H. -'1-NsHsCI
The overall reaction with excess of hydrazine is then :-SnCI4 + 4N~H~
• SnCIs.NsH3-2N~H4+ N~HsCl
(i)
Not more than one Sn-C1 bond seems to be hydrazinolysed in reactions of stannic chloride and hydrazine up to the molar ratio, 1 : 8, studied. If dichloro-dihydrazinostannane, SnCI~(N2Hs)~ is assumed to be formed for a moment then the overall reaction with excess of hydrazine would be expected to take place in the molar ratio 1 : 6 as given below :-SnCI4 + 6NzH4
). SnCls(NiHs)l.2NiH ~ + 2N2HbCl
rather than in the molar ratio l : 4 experimentally obtained. The alternative mechanism for the experimentally observed 1:4 reaction, SnCI, + 4N~H4
~ SnCl2(N2Na)2 + 2NsHrCI
cannot, however, explain a number of our experimental results and is therefore ruled out. The results of thermal decomposition show that IV liberated hydrazine loosely bound to I and this further supports the above mechanism. Hydrazine co-ordinatively bound to I, a poor Lewis acid, would be expected to be lost readily on heating. That I has acceptor properties was established by the preparation of the adduets, VI to VIII by its reactions with hydrazine, pyridine and ~-picoline. The fact that we have been able to prepare the compounds I and VI assumed to be formed in stannic chloride hydrazine reactions conclusively proves the correctness of the mechanism proposed. The results of the interconversions can be explained on the basis of the mechanism proposed above for the stannic chloride hydrazine reactions. When stannic chloride is reacted with excess of hydrazine in the pure state or when the products I to IV are repeatedly washed with anhydrous hydrazine, all the Sn-C1 ~ E. BANNISTERand G. W. A. FOWLES,.!., Chem. Soc. 310-315 (1959).
Reaction of stannic chloride with hydrazine
163
bonds appear to be hydrazinolysed and the polymer V presumably results through the formation of the unstable tetrahydrazinostannane, Sn(N~Ha) v as follows : - SnCl~ -F N,,H,
)' SnCIs'N=Hs -k HCI +
N=H,
N=H¢
SnCl=(N=H~)= + HCI q- N=H~ SnCII ,IsH~)a -k HCI
N=H, X'~4N=H6CI N=H, ~ l
-k NsH, Sn(N~ -Is)~ ÷ HCI
N=H4
l
SnNcN~H 8 + 2N=H4
Similar mechanisms were put forward by PATERSON and OIqYSZCHUK(5) to explain the formation of the boron and aluminium polymers from reactions of hydrazine with the trichlorides of boron and aluminium. As the 1 : 1 and 1 : 2 adducts of trichloromonohydrazino-stannane are insoluble in organic solvents, little information about their structure could be obtained. The 1:2 adducts, SnCIa-N~Ha.2N~H4 and SnCla'N~Ha'2CsHsN are certainly octahedral. The 1 : 1 adduct SnCla.N2Ha CeH4(CHa)N appears to be polymeric and is also probably octahedral through chlorine bridged structure, ts~ The infra-red spectra of compounds I to VI and hydrazine have been recorded; the frequency assignments are given in Table 1. These were made by comparison of these spectra with those of hydrazine c9~and hydrazine monohydrochloride, tx°~ Further the known assignments of the spectra, BFs.NzHI, m) B(CHs)a.N2H4(IS) SiF4.2NsHI (1~ and GeF4.2NsH4 tla~ have been kept in view while interpretating our spectra. EXPERIMENTAL Stannic chloride (B.D.H.) was purified as described by HILDEBRANDand CAR~. aS~ Anhydrous hydrazine was prepared by refluxing 95 q- ~o material (Eastman Kodak) for 3--4 hr over potassium hydroxide pallets and was then distilled. The fraction boiling in the range 111-113° was found to be 100 per cent pure by the iodate method. ~m The solvents (chloroform, ether) were purified by standard methods. The purified reagents were stored in a dry box of low humidity. Infra-red spectral measurements were made in the frequency range 400(b-650 cm-1 using a PerkinElmer Infra-red cord equipped with sodium chloride optics. Samples were examined in nujol mulls and KBr. ~s~E. L. Mtm'rl~ltT~S, J. Amer. Chem. Soc. 82, 1082 (1960). ~'~J. GOUBEAUand E. RICKER,Z. Anorg. chem. 310, 123 (1961); P. A. GIGUERAand I. D. LrU., J. Chem. Phys. 20, 136 (1952). tx0~j. C. DEcros and D. P. PEARSONJ. Amer. Chem. Soc. 75, 2436 (1953). m~ W. G. PA'na~SONand M. ONYSZCHUK,Canad. J. Chem. 39, 986 (1961). cm W. G. PATERSONand M. ONYSZCnUK,Canad. J. Chem. 39, 2324 (1961).
~a~ R. C. AOOAgWALand M. ONYSZCmJK,Unpublished work (1961). tx,~ T. L. BROWNand M. KoBtrrA, J. Amer. Chem. Soc. 83, 4175-77 (1961). ~m j. H. I-IF.~EegANOand J. M. CARTER,Jr. Amer. Chem. Soc. 54, 3594 (1932). ~e~ L. F. AuDpa~-I and B. A. 0 ~ , The Chemistry of Hydrazine. Wiley, New York (1951).
R. C. AGGARWAL and R. C. MAKHUA
164
TABLE 1.----COMPARISON OF INFRA-RED SPECTRA AND AssIGNMENTS SnCI3.N2H8
3225 sh 3075 m
- -
2855 s -- -
- -
SnCIc4N,H4 SnCIs'NsHs-2NaH4
N2I-I4
Assignments
3178 m 3075 m
3283 sh 3075 s
3310 s 3190 s
N - - H stretching
-2855 s -2699 sh 2566 m
--2742 w
2920 m ---
unidentified Nujol
1600 sh
--
--
--
--
NH8 + stretching
--
--
1640 s
1574 s
1590 w
1590 m
1600 s
--NH~ and N H , + deformation (asym)
1560 sh 1502 m
1550 w 1491 m
-1491 s
---
- N H s and NHs + deformation
1448 s
1448 s 1398 s 1360m
-1406 w --
--
(sym) 1360s
--
1243 m
--
- -
l
- -
1055 s 945 s 940 s
l
1
3
s
1086 s 970 s 961 s 945 w
1080 s 945 m
- -
Nujol NHs + bending
Nujol 1330 s 1300 s --
NHs rocking (asym & sym) NII,+ bending
- -
1120-1020 sh 890 s
N H , wagging N - - N stretching
Note: (i) A s Sn-CI and Sn-N cm stretching vibrations occur beyond the range of our instrument no
information on these bands is presented in this table. (ii) s = strong, m = medium, w = weak, b = broad, sh = shoulder, asym = asymmetric and sym = symmetric Preparation and analysis o f compounds
Products II to IV were prepared by reaction (in dilute chloroform solutions) of stannic chloride and hydrazine in different molar proportions. Addition compounds of I were prepared by refluxing about 5 mmoles of this materialwith about 20 mmoles of hydrazine, pyridine, ~-picoline and quinolin¢ in about 100 ml chloroform for about 24 hr. The products were filtered, washed thoroughly with chloroform and dried. The compounds were analysed for tin, hydrazine and chlorine. Tin was estimated as SnOs, chlorine as AgC1 and hydrazine by the iodate m e t h o d : TM Results of analysis are summarized in the Tables 2 and 3. lnterconversions
II and III (about 2 mmoles) were refluxed with hydrazine (3-4 mmoles) in 100 ml of dry chloroform for 4--6 hr. The reaction products were filtered, washed and analysed. The results of analysis show that they were completely converted to IV. (Found: NsN,, 32.3. Calc. for SnClc4N,H~: NsI~, 32.9%.) When II, HI and IV were similarly refluxed with excess of stanic chloride in chloroform for 8 to 10 hr, they were almost completely changed into I. (Found: N2I-I4, 11.2; Sn, 46-1; C1, 44-7; Calc; for SnCIa'NjHs: NsI-~, 12"1; Sn, 46.4; C1,41.5~o.)
Reaction of stannic chloride with hydrazine
165
TAnLE 2.--AN~LYSXS OF TIN ( i V ) CHLORIDE-HYDRAZINE REACTION PRODUCTS Molar Ratio SnCI~: N~H, taken for reaction
Composition of compounds formed
N~H4
Sn
N,H4
Sn
4:1 1:1 1:2 1:3 1:4 1:8
SnCla'NiHa SnCls'NiHs SnC1,.2NsI-I~ SnCI4.3NsH4 SnC14.4NsH4 SnCI4.4N2H4
12"8 12"6 20.7 27.5 32.9 32-4
45"7 45.9 37.2 32-9 30.7 30.9
12"1 12-1 19.7 26.9 32.9 32.9
46"0 46.0 36-7 33-3 30.5 30.5
Calculated ~o
Found (%)
TABLE 3.--ANALYSIS OF ADDUCT$ OF TRICHLOROMONOHYDRAZINO-$TANNANE
Molar ratio SnCls'NsHa and base taken for reaction
Molar ratio 8nCls'N=Ha & base formed in adducts
NsH4
Sn
CI
N2H4
Sn
CI
SnCIa'NsHs:2NsH4 SnCIs-NIH8: 4CsI-~N SnCIa-NIHs :4C6H,(CHs)N *SnCls'NsHa :4CgHTN
1:2 1:2 1:1 1:0
29.9 9.6 9.2 12.8
36.7 28.4 32.5 45.5
32"1 ----
29.7 8.0 8-8 12"1
37"1 28-6 33-9 46.0
33"2 ----
Found (%)
Calculated (~o)
* Quinoline failed to form an adduct with 1 presumably because of steric considerations.
Reaction with concentrated hydrochloric acid When I, II, HI and IV were refluxed with concentrated hydrochloric acid, a clear solution was obtained which on cooling deposited, white crystals of hydrazine dihydrochloride, melting point 198°C. The filtrate contained Sn(IV). A typical reaction is given below:--
SnCI4-4N2H4 + 10HCI = H~[SnCI6] -{- 4NsHeCI 2
Thermal decomposition That SnC1,.4N2H~ loses hydrazine gradually when heated in a vacuum above 100°C was verified by condensing the volatile material and analysing it. IVwas heated in a vacuum ( < 5 mm) at a constant temperature for several hours till the analysis of hydrazine in the residue became almost constant. The temperature was then raised by about 20°C and the process repeated. Measurements were made in the temperature range 80-200°C and it was found that the fiberation of hydrazine increases linearly with temperature. At 170°C the hydrazine in the residue corresponded to SnCls-NgHs. Further, a white sublimate of ammonium chloride and uncondensable gases were obtained around this temperature. These observations indicate the following mode of decomposition at 170°C.
2SnCI,.4N2H~
• 2SnCls'NzHa + 5N2 -I- 9H~ + 2NH4CI
The residue at 210°C did not contain any hydrazine but gave tests for tin, NI-I4+ and CI-. This, when heated at about 300-400°C, yielded a white water soluble sublimate of ammonium hexachlorostannate. (Found: Sn, 34.0. Calc. for (NI-~BSnCI6; Sn, 32.2%.) The black nonvolatile residue left in the flask gave tests for tin, and nitrogen. The observed results at 300-400°C can be explained on the basis of the following mode of thermal decomposition.
2SnCI~'4NsH4
> SnN2 + (NH~)s[SnCI6] + 2NH4CI -I- SN2 -f- 8Ns
Acknowledgement The author's grateful acknowledgements are due to the Council of Scientific and Industrial Research, New Delhi (India) for the award of Junior Research Fellowship to one of them (RCM). The authors are also thankful to the Head of the Chemistry Department for providing the laboratory facilities and to Dr. M. ONYSZCHUK, McGill University, Montreal for his kind help in the form of chemicals and equipment.