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The ponomarenko reaction — A convenient one-step synthesis of chlorinated aromatic pollution standards from nitro compounds
Chemosphere No. 3, pp 191 - 19&, 1976.
Pergamon Press.
Printed in Great Britain.
THE PONOMARENKO REACTION - A CONVENIENT ONE-STEP SYNTHESIS OF CHLORINATED AROMATIC POLLUTION STANDARDS FROM NITRO COMPOUNDS
6. Sundstr~m, Laboratory of Environmental Chemistry, University of Amsterdam, Nieuwe Achtergracht 166 Amsterdam, Th6 Netherlands.
(Received in UK for publication 8 April 1976)
The introduction of chlorine in aromatic systems is usually achieved by direct chlorination with chlorine gas or via the Sandmeyer reaction. The amino function required for the latter reaction may in turn be obtained by the reduction of a nitro group. Aromatic nitro groups can, however, be converted to chlorine by a simple one-step reaction which involves treatment of the nltro compound with tetrachloromethane at 250-300 ° . Little attention seem to have been paid to thls synthetic route after it was first descrlbed In a series of papers by I-4 Ponomarenko .
We recently used the method f o r the synthesls of some hexa- and octachlorobiphenyls from t e t r a c h l o r o d i n l t r o - , h e x a c h l o r o d l n l t r o - and heptachloronitrobiphenyls5-7. The reaction proceeds In e x c e l l e n t y l e l d s with these hlghly deactivated compounds. E,g. the conversion of compound l a to the octachloroblphenyl 2a was achieved in a q u a n t l t a t l v e y l e l d 7. The corresponding conversion via reduction and subsequent Sandmeyer reaction has been reported to 9 i r e a t o t a l y i e l d of
35%8.
Cl-(,
,)--(,
,)-0
CCI4280-90°
CI C)
CI
1._~a
2a
191
0
192
No. 3
In the original papers the reaction was applied to aromatic systems like benzene, biphenyl, naphtalene, antraqulnone and phtalimldes containing I-3 nitro groups. Activating substituents such as alkyl groups were not compatible with the forcing reaction conditlons and only -Br, -S02CI , -CN and -COOH substltuents were reported to withstand the high temperatures needed for reaction (see below). However, only in the case of a few benzene derivatives a thorough description of reaction conditions and yield of products were given. Durlng the studies on the chemistry of possible environmental
pollutants we have synthe-
sised a number of aromatic chlorine compounds from nitro- or nitrochloro compounds by the Ponomarenko reaction (Table I). The reaction have proved to be of great ~alue for the synthesis of small amounts of reference compounds. The nitronaphthalenes
investlgated (Table I) gave in most cases a major product which was
easlly purlfled by crystallisation or by chromatography.
In some cases the structure of the
byproducts were determined and it was shown that further chlorination had occurred at one of the reactive e-positlons of the naphthalene nucleus.
Thus,
1,4,6-trlchloronaphthalene was iso-
lated from the reaction of compounds Id and le with carbon tetrachloride and octachloronaphthalene from the reaction of lh. However,
Increasing substsitutlon with chlorine or nitro groups
and the concomitant deactivation seem to inhibit this side-reaction the high amount of octachloronaphthalene
(14%) formed from compound lh being a exception. The mononltro compound 1_bb
was obviously too reactive under the conditions studied and gave several
products. Attempts
to avoid further chlorination by shortening of the reaction time did not substancially change the composition of products but resulted In recovery of starting material. The Ponomarenko reaction was also succesfully used for the synthesls of two chlorinated 12 in e.R. chlorophenol preparations . The conver-
diphenyl ethers (2i-21) known as contaminants sion of 2,7-dinltro-9-fluorenone illustration to the usefulness
(Im) to be the corresponding dichloro compound give further of thls reaction.
Finally it should be mentloned that attempts by us to convert 3-bromo-4-nltrobibhenyl the chloro compound
to
led to a mixture of mono- and dichloroblphenyls only. This is in contrast
to the report by Ponomarenko who stated that bromine substltuents are stable during the reaction conditions. EXPERIMENTAL.
Exchange of n i t r o groups f o r c h l o r i n e . General Procedure. Ca___~.0.15 g o f the n i t r o compound and 0.8 ml t e t r a c h l o r o m e t h a n e in a glass ampoule (Pyrex, i.d. 6 mm, I. 80 mm) was heated for 30 min. at 250-56 °. After opening of the ampoule (inner pressure posslble!) most of the tetrachloromethane was exchanged for hexane and polymeric material removed by filtratlon by a small column (Pasteur pipette) of alumlnlum oxide (neutral, activity grade I) which was eluted with hexane. The more polar compounds (21-2m) were eluted with mixtures of hexane and ethyl acetate. The major chloro compounds were flnally obtained in a pure slate by crystalllsatlon from ethanol or by preparative thin layer chromatography on silica gel with hexane,
hexane~ethyl acetate (4:1) (2i-21) or chloroform (2m) as solvent.
Me ltlng points were determlned on a Kofler mlcro hot-plate and are uncorrected. New compounds
No. 3
193
Table I. Chloro-substifufed compounds(2) obtained by treatment of aromatic nitro compounds(1) with fefrachloromefhaneat 250-256°. Nitro compound
Ch[orosubstituted product Strudvre Y+etd,%
11:){ ~ ~ NO2
(m Piit)a
mixture of C10H6CI2 compds 90 (3
,NO2 lc ~ N 0 2
90
56-57.5 (60-61)
85
87-88,5 (89)
90
86-88 (89)
90
88-89 {92)
2
CI If [ ~
No2
CI 2_! ~ C I
NO2 0 19.
NO2
70
a [iferafure va[ues from Ref.g.
were characterised
by mass spectrometry and proton NMR spectroscopy.
References. 1. Ponomarenko, A.A., Zh. Obshch. Khlm., 3__2, 4029(1962). 2. Ponomarenko, A.A., Zh. Obshch. Khim., 3--2, 4035(1962). 3. Ponomarenkop A.A. and Tsyblna, N.A., Zh. Obshch. Khlm., 3-2, 4018(1962). 4. Ponomarenko, A.A., Dopovldi Akad, Nauk Ukr. RSR., !963, 787.
78-80
t81)
19~
No. 3
Tabte 1 continued. Chioro substituted product
Nitro compound
SfnJcfure
Yield,%
80
2._b
m.~,.
(mp lit) 175-180a (-)
CI oil (39-40)b
1,
oil
(o,) b O
0
CI
NO2
2~
CI
75
Cl
(~
oil (-)
I,I
~ ~O~No
2
oil (-) 0
0
2m
C
~
90
195-197 (191)c
a this product contained I~, 10% odachioronaphfhalene which could not be removed by crysfatiisafion or chromafography. b from Ref. 10, c from Ref, 11. 5. Sundstr~m, G., Acta Chem. Scand., 27, 1109(1973). 6. SundstrSm, G., Bull. Envlron. Contam. Toxlcol., 11, 39(1974). 7. Sundstr~m, G., Chemical Communlcatlons
Unlverslty of Stockholm,
8. Safe, S. and Hutzinger , 0., J. Chem. Soc. Perkln Trans.,
1974, No. 10, p. 18 (Thesis)
Ir ]972, 686.
9. Rodd, E.H. and van Alphen, J., In: Chemistry of Carbon Compounds, E.H. Rodd, ed. Vol. IIIB, Elsevier, Amsterdam,
1956, p. 1290.
10. Suter, C.M. and Green, F.O., J. Amer. Chem. Soc., 59, 2578(1937). 11. Courtot, C. and Vlgnatl , C., Compt. Rend., 184, 1180(1927). 12. Nllsson, C.A. and Renber9, L., J. Chromato9. , 89, 325(1974).
Pergamon Press.
Printed in Great Britain.
THE PONOMARENKO REACTION - A CONVENIENT ONE-STEP SYNTHESIS OF CHLORINATED AROMATIC POLLUTION STANDARDS FROM NITRO COMPOUNDS
6. Sundstr~m, Laboratory of Environmental Chemistry, University of Amsterdam, Nieuwe Achtergracht 166 Amsterdam, Th6 Netherlands.
(Received in UK for publication 8 April 1976)
The introduction of chlorine in aromatic systems is usually achieved by direct chlorination with chlorine gas or via the Sandmeyer reaction. The amino function required for the latter reaction may in turn be obtained by the reduction of a nitro group. Aromatic nitro groups can, however, be converted to chlorine by a simple one-step reaction which involves treatment of the nltro compound with tetrachloromethane at 250-300 ° . Little attention seem to have been paid to thls synthetic route after it was first descrlbed In a series of papers by I-4 Ponomarenko .
We recently used the method f o r the synthesls of some hexa- and octachlorobiphenyls from t e t r a c h l o r o d i n l t r o - , h e x a c h l o r o d l n l t r o - and heptachloronitrobiphenyls5-7. The reaction proceeds In e x c e l l e n t y l e l d s with these hlghly deactivated compounds. E,g. the conversion of compound l a to the octachloroblphenyl 2a was achieved in a q u a n t l t a t l v e y l e l d 7. The corresponding conversion via reduction and subsequent Sandmeyer reaction has been reported to 9 i r e a t o t a l y i e l d of
35%8.
Cl-(,
,)--(,
,)-0
CCI4280-90°
CI C)
CI
1._~a
2a
191
0
192
No. 3
In the original papers the reaction was applied to aromatic systems like benzene, biphenyl, naphtalene, antraqulnone and phtalimldes containing I-3 nitro groups. Activating substituents such as alkyl groups were not compatible with the forcing reaction conditlons and only -Br, -S02CI , -CN and -COOH substltuents were reported to withstand the high temperatures needed for reaction (see below). However, only in the case of a few benzene derivatives a thorough description of reaction conditions and yield of products were given. Durlng the studies on the chemistry of possible environmental
pollutants we have synthe-
sised a number of aromatic chlorine compounds from nitro- or nitrochloro compounds by the Ponomarenko reaction (Table I). The reaction have proved to be of great ~alue for the synthesis of small amounts of reference compounds. The nitronaphthalenes
investlgated (Table I) gave in most cases a major product which was
easlly purlfled by crystallisation or by chromatography.
In some cases the structure of the
byproducts were determined and it was shown that further chlorination had occurred at one of the reactive e-positlons of the naphthalene nucleus.
Thus,
1,4,6-trlchloronaphthalene was iso-
lated from the reaction of compounds Id and le with carbon tetrachloride and octachloronaphthalene from the reaction of lh. However,
Increasing substsitutlon with chlorine or nitro groups
and the concomitant deactivation seem to inhibit this side-reaction the high amount of octachloronaphthalene
(14%) formed from compound lh being a exception. The mononltro compound 1_bb
was obviously too reactive under the conditions studied and gave several
products. Attempts
to avoid further chlorination by shortening of the reaction time did not substancially change the composition of products but resulted In recovery of starting material. The Ponomarenko reaction was also succesfully used for the synthesls of two chlorinated 12 in e.R. chlorophenol preparations . The conver-
diphenyl ethers (2i-21) known as contaminants sion of 2,7-dinltro-9-fluorenone illustration to the usefulness
(Im) to be the corresponding dichloro compound give further of thls reaction.
Finally it should be mentloned that attempts by us to convert 3-bromo-4-nltrobibhenyl the chloro compound
to
led to a mixture of mono- and dichloroblphenyls only. This is in contrast
to the report by Ponomarenko who stated that bromine substltuents are stable during the reaction conditions. EXPERIMENTAL.
Exchange of n i t r o groups f o r c h l o r i n e . General Procedure. Ca___~.0.15 g o f the n i t r o compound and 0.8 ml t e t r a c h l o r o m e t h a n e in a glass ampoule (Pyrex, i.d. 6 mm, I. 80 mm) was heated for 30 min. at 250-56 °. After opening of the ampoule (inner pressure posslble!) most of the tetrachloromethane was exchanged for hexane and polymeric material removed by filtratlon by a small column (Pasteur pipette) of alumlnlum oxide (neutral, activity grade I) which was eluted with hexane. The more polar compounds (21-2m) were eluted with mixtures of hexane and ethyl acetate. The major chloro compounds were flnally obtained in a pure slate by crystalllsatlon from ethanol or by preparative thin layer chromatography on silica gel with hexane,
hexane~ethyl acetate (4:1) (2i-21) or chloroform (2m) as solvent.
Me ltlng points were determlned on a Kofler mlcro hot-plate and are uncorrected. New compounds
No. 3
193
Table I. Chloro-substifufed compounds(2) obtained by treatment of aromatic nitro compounds(1) with fefrachloromefhaneat 250-256°. Nitro compound
Ch[orosubstituted product Strudvre Y+etd,%
11:){ ~ ~ NO2
(m Piit)a
mixture of C10H6CI2 compds 90 (3
,NO2 lc ~ N 0 2
90
56-57.5 (60-61)
85
87-88,5 (89)
90
86-88 (89)
90
88-89 {92)
2
CI If [ ~
No2
CI 2_! ~ C I
NO2 0 19.
NO2
70
a [iferafure va[ues from Ref.g.
were characterised
by mass spectrometry and proton NMR spectroscopy.
References. 1. Ponomarenko, A.A., Zh. Obshch. Khlm., 3__2, 4029(1962). 2. Ponomarenko, A.A., Zh. Obshch. Khim., 3--2, 4035(1962). 3. Ponomarenkop A.A. and Tsyblna, N.A., Zh. Obshch. Khlm., 3-2, 4018(1962). 4. Ponomarenko, A.A., Dopovldi Akad, Nauk Ukr. RSR., !963, 787.
78-80
t81)
19~
No. 3
Tabte 1 continued. Chioro substituted product
Nitro compound
SfnJcfure
Yield,%
80
2._b
m.~,.
(mp lit) 175-180a (-)
CI oil (39-40)b
1,
oil
(o,) b O
0
CI
NO2
2~
CI
75
Cl
(~
oil (-)
I,I
~ ~O~No
2
oil (-) 0
0
2m
C
~
90
195-197 (191)c
a this product contained I~, 10% odachioronaphfhalene which could not be removed by crysfatiisafion or chromafography. b from Ref. 10, c from Ref, 11. 5. Sundstr~m, G., Acta Chem. Scand., 27, 1109(1973). 6. SundstrSm, G., Bull. Envlron. Contam. Toxlcol., 11, 39(1974). 7. Sundstr~m, G., Chemical Communlcatlons
Unlverslty of Stockholm,
8. Safe, S. and Hutzinger , 0., J. Chem. Soc. Perkln Trans.,
1974, No. 10, p. 18 (Thesis)
Ir ]972, 686.
9. Rodd, E.H. and van Alphen, J., In: Chemistry of Carbon Compounds, E.H. Rodd, ed. Vol. IIIB, Elsevier, Amsterdam,
1956, p. 1290.
10. Suter, C.M. and Green, F.O., J. Amer. Chem. Soc., 59, 2578(1937). 11. Courtot, C. and Vlgnatl , C., Compt. Rend., 184, 1180(1927). 12. Nllsson, C.A. and Renber9, L., J. Chromato9. , 89, 325(1974).