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Sonochemistry in SRN1 reactions in liquid ammonia at room temperature
TetrAr&oa
0040~4039(93)EO3
Sonochemistry
in S,,l
L.strers, Vol. 35, No. 5. pp. 677-680. 1994 Elsevier Science Ltd F’rinted in Great Britain 0040~4039/?J4 56.C0+0.00
17-D
Reactions in Liquid Ammonia Temperature
at Room
Pablo G. Manzo, Sara M. Pahcios, and RubBn A. Alonso*
CEQUIMAP,
Fact&ad
de Cienoias
Key
p-Iodoantsole
Abstract:
mechantsm
The aromattc substitutton
Quhmcas,
words:
ultrasound,
radical nucleophilic aromatic
process, and the propagatton
Nactonal
stimulated
substitution,
nucleophihc
(Cl, Br, I) react with Ph$
possessmg
subsbtutton
suitable leavmg
radtcals
When ET does not occur spontaneously,
lnttiatton
Propagatton
electrons,’
The mechantsm
the nueleophilic
of the reactton
and radical antons are mtermedrates
step, such as eq. 1 In a few systems, spontaneous
generated
by the S,, 1
is a chant
I
III whda
substrate
by cathodically
ions tn liquid ammonia
groups
process requires an mtttanon
ammonia,’
substatutton
by ultrasound
steps are shown m Scheme I
has been observed.’
Suc.16, C C.61, 5016 C6rdobaARGENTBJA
or S,, 1, has been shown to be an excellent means of affectmg
compounds
Scheme 1 depicts a nucleophihc
de Cbrdoba,
I, electrontransfer,
S,,
and I-halonaphthalenes
at room temperature
of unactivated
Umverstdad
or by certain tnorgantc
electron
However,
this chain
transfer (ET) from the nucleophile
tt can be induced by light,’ by solvated electrons salts6
Step.
Steps
R’ +
RX
+
>
Nu- -
Nu-
5
677
(RNU)’
RNU
+
3
x-
to the
m liquid
5
678
We have become interested [Na(Hg)]
in other methods
to initiate the S,,l
reacts with aryl halides m liquid ammoma’,
diphenylphospmde
(PhQ’) ions’ and oarbanions’
There is an increasing reports about this subject.‘* Liquid ammonia of this solvent, perform
interest in the use of sonochemical
is one of the best solvents for S, 1 reactions
m liquid ammonia
The reaction and the substitution
(p&U)
there is an important
after oxidation
of aryl halides and
but smce the reactions
are camed
out at the boilmg point
Saul reactions,
we designed
a metallic
reactor
to
(CO. 25OC and 9 Kgr/cm*). We report here the results
of ultrasound.
was obtained
(-33°C) m 45 nun. gives 30% yield of iodide ions, in 26% yield,”
obtained
is through
in the yield of substitution was inhibited
there is an mcrease
together
with 5% of anisole (Table
an &.,I reaotion.‘z
m liquid ammonia product.
by p-dmitrobenxene
was 29%, Table 1, run 7). There was no Increase m the yield when that with ultrasound
shown by the number of on oliphatic halides.‘Ob
at room temperature
increase
clearly reactions
and pressure
(Table I, run 5). This reaction
All these results suggest
found that sodium amalgam reactions
S,l
on aromatic
ET, and the product
with the reaction
synthesis.
to catalyze
with Ph,P- tons in bqutd ammoma
there is a spontaneous
at room temperature
tp-An)PhgO
at room temperature
isolated as the oxide tp-An)&PO,
The same results were obtained ultrasound
of ultrasound
with PhrP- ions and the influence
of p-iodoamsole product,
I. run 1). In thy reaction
of (p-An)Ph$‘O
methods in organic
There is only one report of the use of ultrasound
of haloerenes
Thus we recently
in liquid ammonia.
and m order to study the influence
the reactions
of the reactions
reactions
and also it is a sunable reagent to initiate Ss,l
the reaction
(Table 1, ruu 2). However,
with
Thus m 45 min there was a 75% (p-DNB) (In 45 min the yield of
tune
was mcreased
(Table I. run 6)
m the rate of the Saul reaction
Ill’ p-IAn
Phg-
+
> @-An)Php
+
I
Sax1
In the reactton naphthalene, result suggests protonated
of 1-iodonaphthalene
and only 3% of the substitution that Php
to gave naphthalene,
When the reaction
was carried
when the same reactron
that the ET reactton
as substrate
but the yield increases All these results clearly
indicate
with ultrasound,
reactron, increases
1mechanism.
with 50% yield of both reactions,
but
up to 70% (Table I, run 10).
for this reaction.
Indeed,
ultrasound
there was only 30% of Br’ ions in 60 min.
there was a 94% yield of substttution wnh only 6% yield of naphthalene,
[Table I, run 1 I-12). When this reaction
of the yield of the substitution
is catalyzed
product,
product
when
which suggests was carried out
with an increase of naphthalene
by ultrasound.
with Ph$- at room temperature
in 60 nun (7% of the substitution
(Table I, runs 14-15).
that it is possrble to perform
is increased
product increases
aruon. which IS
by an Y,,
meohamsrn
product. However,
of 1-chloronaphthalene
to 30% with ultrasound
and that the rate of the ET reactions
of C(I. 6OpC in the temperature
with ultrasound
decrease
(Table I, run 8) This
to give naphthalene
there was 100% of dehalogenahon
ruled out an aryne rnecluousm
condmons
that the substitutron
There is only a small reaction
exchange”
with Ph&‘- ions at room temperature
much more quickly
there was an nnportant
was obtained”
is formed in small amounts
the yield of the substitution
is formed,
out in the same experimental
(Table I, run 13), which indicates
product),
product
product
The tncrease
and 10% of the substitution
was stimulated
ur the presence ofp-DNB,
product.
much faster than the other competmg of 1BrNaph
giving co. 10% of naphthalene
the reaction was camed
by a metal-halogen
and the substitution
was carried out with ultrasound,
the ET reaction In the reaction
isolated as the oxide (1-Naph)PhpO
out at room temperature,
and 45% yield of the substrtuuon
The fact that only the ipso substitution catalyzes
product,
ions react rnsmly with this substrate
by the ammonia
naphthalene
(1 -INaph) with Php’ ions at -33°C there was 20% of I’ ions, but the main product was
by ultrasound
easily the reactions
of liquid ammonia
Studies 111other ET reactions
are in progress
at room temperature
679
Acknorkdgma~h:
The authors are tbankfid
fellowship
from the Consejo
CONICET,
CONICOR
TABLE I:
and SECYTECOR,
Reactions
RUII
Arl
to Dr. Roberto A. Roaai for valuable
de Iavestigaciones
de la Provmcia
da Gkdoba
PGM acknowle?lges
receipt of a
Thu work was supported in part by
Argentina.
of Ha1oare.ne.s with Php‘ Ions m Liqmd Ammoma
Phg
~scussions.
(CONICOR).
Time (min)
Conditloas
Catalyzed
by Ultrasound.’
1.
ArP(O)Ph,
(%)
mm01
ArH (%)
1
p-IAn
1.5
45
30
26
5
2
p-IAn
1.5
60
30
20
IO
3
p-IAn
15
15
17
4
P-b
1.5
30
50
22
7
5
p-IAn
1.5
45
87
7s
7
6
p-IAn
1.5
60
90
70
13
7’
p-IAll
1.5
45
40
29
3
8
1-INaph
3.0
15
20
3
16
9
1-INaph
3.0
15
100
45
50
IO
I -INaph
3.0
15
100
70
30
11
1-BrNaph
6.0
60
30
10
IO
12
1-BrNaph
6.0
60
100
94
6
13’
I -BrNaph
6.0
60
20
20
14
l-ClNaph
6.0
60
10
7
2
IS
I-ClNaph
6.0
60
60
30
4
’ Reactions
carried
halonaphthalenes
b
out in ea. 150 mL of liquid ammonia
(Cl, Br, I). rt = room temperature
b
wltb 1.0 mm01 of substrate.
b Not quantified
p-IAn
= p-iodoanisole,
’ p-DNB (20 mol%) was added.
b
I-XNaph
= l-
680
REFERENCES-AND
1
For reviews, see. (a) Norrts, R. K., The Chemistty
ofFunctionaI
NOTES
Groups, Patai, S., Rappoport, 2.. Eds
UK, 1983; Supplement D, Chapter 16. (b) Rossi, R. A.; de Rossi, R H.; Aromatic Substitution
; Wiley, Chiohester,
by the &,,I Mechanism,
ACS Monograph 178; American Chemical Society Washington, DC, 1983 2.
(a) Kun. J K; Bunnett, J. F.; J. Am Chem. Sot., 1970,92.7463.
(b) Scamehom, R. G.; Bunnett. J. F., J. Org. Chcm. 1977,
42, 1449 (c) Soamehorn, R. G.; Hardacre: J. M., Lukamch, J. M.; J. Org. Chem. 1984, 49, 4881 3
(a) ROSSI,R. A.; Bunnett, J. F., J. Org. Chem. 1973, 38, 1407. (b) Hoz, S.; Bunnett, J. F., J. Am. Chem. Sot. 1977, 99, 4690. (c) Fox, M. A., Younathan, J , Fryxell, G E.; J. Org. Chem. 1983, 48,3 109.
4.
(a) Kim. J. K; Bunnett, J. F., J. Am. Chem. Sot. 1970,92,
7464. (5) ROSSI,R. A; Bunnett, J.
F , J. Am. Chcm. Sot. 1974,
96, 112. (a) Saveant, J. hf.; Ace. Chem. Res. 1980, 13,323
(b) Saveant, J. M., Adv. Phys. 0%. Chem. 1998,26,
I, and references
crted therein. 6
Galli, C.; Bunnett. J F.; J. Am. Chem. Sot. 1984, 49, 3041
7
Austm. E . Alonso, R. A., Rossi, R A., J. Chem. Res. 1998, 190
8.
Austm, E
9.
Austin, E., Ferrayoli, C. G.. Alonso, R. A., Rossi, R A., Tetrahedron
IO
(a) Emhorn, C., Einhom, J ; Luohe, J. L., J. Synt. Org. Chsm. 1989, 1 I, 787
11
Isolated and quantrtied as the OXI&, compared with an authentical sample, see Austin, E, Alonso, R. A., Rosa, R. A., J.
, Alonso,R. A.; Roost, R A., J. Org. Chem. 1991. 56,4486
M. J., Lucke, J L., Tetrclhedron Lett
1993, 49, 4495.
, and references crte.d therem. (b) Dickens,
1991, 32, 470
Org. C/tern.. 1991, S6,4489 12
Swartz, J. E., Bunnett, J F.; J. Org. Chom.. 1979, 44, 340.
13
There are reports of halogen-metal exchange wtth RF
tons, see Bengerter, B. W.; Beatty. R. P , Kouba, J. K.; Wreford,
S. S., f. Org. Chem. 1977. 42, 3247. Meijs, G F., Tetrahedron Latt. 1985. 26, 105.
(Received in USA 19August 1993; revised 13 October 1993;accepted 23 November 1993)
0040~4039(93)EO3
Sonochemistry
in S,,l
L.strers, Vol. 35, No. 5. pp. 677-680. 1994 Elsevier Science Ltd F’rinted in Great Britain 0040~4039/?J4 56.C0+0.00
17-D
Reactions in Liquid Ammonia Temperature
at Room
Pablo G. Manzo, Sara M. Pahcios, and RubBn A. Alonso*
CEQUIMAP,
Fact&ad
de Cienoias
Key
p-Iodoantsole
Abstract:
mechantsm
The aromattc substitutton
Quhmcas,
words:
ultrasound,
radical nucleophilic aromatic
process, and the propagatton
Nactonal
stimulated
substitution,
nucleophihc
(Cl, Br, I) react with Ph$
possessmg
subsbtutton
suitable leavmg
radtcals
When ET does not occur spontaneously,
lnttiatton
Propagatton
electrons,’
The mechantsm
the nueleophilic
of the reactton
and radical antons are mtermedrates
step, such as eq. 1 In a few systems, spontaneous
generated
by the S,, 1
is a chant
I
III whda
substrate
by cathodically
ions tn liquid ammonia
groups
process requires an mtttanon
ammonia,’
substatutton
by ultrasound
steps are shown m Scheme I
has been observed.’
Suc.16, C C.61, 5016 C6rdobaARGENTBJA
or S,, 1, has been shown to be an excellent means of affectmg
compounds
Scheme 1 depicts a nucleophihc
de Cbrdoba,
I, electrontransfer,
S,,
and I-halonaphthalenes
at room temperature
of unactivated
Umverstdad
or by certain tnorgantc
electron
However,
this chain
transfer (ET) from the nucleophile
tt can be induced by light,’ by solvated electrons salts6
Step.
Steps
R’ +
RX
+
>
Nu- -
Nu-
5
677
(RNU)’
RNU
+
3
x-
to the
m liquid
5
678
We have become interested [Na(Hg)]
in other methods
to initiate the S,,l
reacts with aryl halides m liquid ammoma’,
diphenylphospmde
(PhQ’) ions’ and oarbanions’
There is an increasing reports about this subject.‘* Liquid ammonia of this solvent, perform
interest in the use of sonochemical
is one of the best solvents for S, 1 reactions
m liquid ammonia
The reaction and the substitution
(p&U)
there is an important
after oxidation
of aryl halides and
but smce the reactions
are camed
out at the boilmg point
Saul reactions,
we designed
a metallic
reactor
to
(CO. 25OC and 9 Kgr/cm*). We report here the results
of ultrasound.
was obtained
(-33°C) m 45 nun. gives 30% yield of iodide ions, in 26% yield,”
obtained
is through
in the yield of substitution was inhibited
there is an mcrease
together
with 5% of anisole (Table
an &.,I reaotion.‘z
m liquid ammonia product.
by p-dmitrobenxene
was 29%, Table 1, run 7). There was no Increase m the yield when that with ultrasound
shown by the number of on oliphatic halides.‘Ob
at room temperature
increase
clearly reactions
and pressure
(Table I, run 5). This reaction
All these results suggest
found that sodium amalgam reactions
S,l
on aromatic
ET, and the product
with the reaction
synthesis.
to catalyze
with Ph,P- tons in bqutd ammoma
there is a spontaneous
at room temperature
tp-An)PhgO
at room temperature
isolated as the oxide tp-An)&PO,
The same results were obtained ultrasound
of ultrasound
with PhrP- ions and the influence
of p-iodoamsole product,
I. run 1). In thy reaction
of (p-An)Ph$‘O
methods in organic
There is only one report of the use of ultrasound
of haloerenes
Thus we recently
in liquid ammonia.
and m order to study the influence
the reactions
of the reactions
reactions
and also it is a sunable reagent to initiate Ss,l
the reaction
(Table 1, ruu 2). However,
with
Thus m 45 min there was a 75% (p-DNB) (In 45 min the yield of
tune
was mcreased
(Table I. run 6)
m the rate of the Saul reaction
Ill’ p-IAn
Phg-
+
> @-An)Php
+
I
Sax1
In the reactton naphthalene, result suggests protonated
of 1-iodonaphthalene
and only 3% of the substitution that Php
to gave naphthalene,
When the reaction
was carried
when the same reactron
that the ET reactton
as substrate
but the yield increases All these results clearly
indicate
with ultrasound,
reactron, increases
1mechanism.
with 50% yield of both reactions,
but
up to 70% (Table I, run 10).
for this reaction.
Indeed,
ultrasound
there was only 30% of Br’ ions in 60 min.
there was a 94% yield of substttution wnh only 6% yield of naphthalene,
[Table I, run 1 I-12). When this reaction
of the yield of the substitution
is catalyzed
product,
product
when
which suggests was carried out
with an increase of naphthalene
by ultrasound.
with Ph$- at room temperature
in 60 nun (7% of the substitution
(Table I, runs 14-15).
that it is possrble to perform
is increased
product increases
aruon. which IS
by an Y,,
meohamsrn
product. However,
of 1-chloronaphthalene
to 30% with ultrasound
and that the rate of the ET reactions
of C(I. 6OpC in the temperature
with ultrasound
decrease
(Table I, run 8) This
to give naphthalene
there was 100% of dehalogenahon
ruled out an aryne rnecluousm
condmons
that the substitutron
There is only a small reaction
exchange”
with Ph&‘- ions at room temperature
much more quickly
there was an nnportant
was obtained”
is formed in small amounts
the yield of the substitution
is formed,
out in the same experimental
(Table I, run 13), which indicates
product),
product
product
The tncrease
and 10% of the substitution
was stimulated
ur the presence ofp-DNB,
product.
much faster than the other competmg of 1BrNaph
giving co. 10% of naphthalene
the reaction was camed
by a metal-halogen
and the substitution
was carried out with ultrasound,
the ET reaction In the reaction
isolated as the oxide (1-Naph)PhpO
out at room temperature,
and 45% yield of the substrtuuon
The fact that only the ipso substitution catalyzes
product,
ions react rnsmly with this substrate
by the ammonia
naphthalene
(1 -INaph) with Php’ ions at -33°C there was 20% of I’ ions, but the main product was
by ultrasound
easily the reactions
of liquid ammonia
Studies 111other ET reactions
are in progress
at room temperature
679
Acknorkdgma~h:
The authors are tbankfid
fellowship
from the Consejo
CONICET,
CONICOR
TABLE I:
and SECYTECOR,
Reactions
RUII
Arl
to Dr. Roberto A. Roaai for valuable
de Iavestigaciones
de la Provmcia
da Gkdoba
PGM acknowle?lges
receipt of a
Thu work was supported in part by
Argentina.
of Ha1oare.ne.s with Php‘ Ions m Liqmd Ammoma
Phg
~scussions.
(CONICOR).
Time (min)
Conditloas
Catalyzed
by Ultrasound.’
1.
ArP(O)Ph,
(%)
mm01
ArH (%)
1
p-IAn
1.5
45
30
26
5
2
p-IAn
1.5
60
30
20
IO
3
p-IAn
15
15
17
4
P-b
1.5
30
50
22
7
5
p-IAn
1.5
45
87
7s
7
6
p-IAn
1.5
60
90
70
13
7’
p-IAll
1.5
45
40
29
3
8
1-INaph
3.0
15
20
3
16
9
1-INaph
3.0
15
100
45
50
IO
I -INaph
3.0
15
100
70
30
11
1-BrNaph
6.0
60
30
10
IO
12
1-BrNaph
6.0
60
100
94
6
13’
I -BrNaph
6.0
60
20
20
14
l-ClNaph
6.0
60
10
7
2
IS
I-ClNaph
6.0
60
60
30
4
’ Reactions
carried
halonaphthalenes
b
out in ea. 150 mL of liquid ammonia
(Cl, Br, I). rt = room temperature
b
wltb 1.0 mm01 of substrate.
b Not quantified
p-IAn
= p-iodoanisole,
’ p-DNB (20 mol%) was added.
b
I-XNaph
= l-
680
REFERENCES-AND
1
For reviews, see. (a) Norrts, R. K., The Chemistty
ofFunctionaI
NOTES
Groups, Patai, S., Rappoport, 2.. Eds
UK, 1983; Supplement D, Chapter 16. (b) Rossi, R. A.; de Rossi, R H.; Aromatic Substitution
; Wiley, Chiohester,
by the &,,I Mechanism,
ACS Monograph 178; American Chemical Society Washington, DC, 1983 2.
(a) Kun. J K; Bunnett, J. F.; J. Am Chem. Sot., 1970,92.7463.
(b) Scamehom, R. G.; Bunnett. J. F., J. Org. Chcm. 1977,
42, 1449 (c) Soamehorn, R. G.; Hardacre: J. M., Lukamch, J. M.; J. Org. Chem. 1984, 49, 4881 3
(a) ROSSI,R. A.; Bunnett, J. F., J. Org. Chem. 1973, 38, 1407. (b) Hoz, S.; Bunnett, J. F., J. Am. Chem. Sot. 1977, 99, 4690. (c) Fox, M. A., Younathan, J , Fryxell, G E.; J. Org. Chem. 1983, 48,3 109.
4.
(a) Kim. J. K; Bunnett, J. F., J. Am. Chem. Sot. 1970,92,
7464. (5) ROSSI,R. A; Bunnett, J.
F , J. Am. Chcm. Sot. 1974,
96, 112. (a) Saveant, J. hf.; Ace. Chem. Res. 1980, 13,323
(b) Saveant, J. M., Adv. Phys. 0%. Chem. 1998,26,
I, and references
crted therein. 6
Galli, C.; Bunnett. J F.; J. Am. Chem. Sot. 1984, 49, 3041
7
Austm. E . Alonso, R. A., Rossi, R A., J. Chem. Res. 1998, 190
8.
Austm, E
9.
Austin, E., Ferrayoli, C. G.. Alonso, R. A., Rossi, R A., Tetrahedron
IO
(a) Emhorn, C., Einhom, J ; Luohe, J. L., J. Synt. Org. Chsm. 1989, 1 I, 787
11
Isolated and quantrtied as the OXI&, compared with an authentical sample, see Austin, E, Alonso, R. A., Rosa, R. A., J.
, Alonso,R. A.; Roost, R A., J. Org. Chem. 1991. 56,4486
M. J., Lucke, J L., Tetrclhedron Lett
1993, 49, 4495.
, and references crte.d therem. (b) Dickens,
1991, 32, 470
Org. C/tern.. 1991, S6,4489 12
Swartz, J. E., Bunnett, J F.; J. Org. Chom.. 1979, 44, 340.
13
There are reports of halogen-metal exchange wtth RF
tons, see Bengerter, B. W.; Beatty. R. P , Kouba, J. K.; Wreford,
S. S., f. Org. Chem. 1977. 42, 3247. Meijs, G F., Tetrahedron Latt. 1985. 26, 105.
(Received in USA 19August 1993; revised 13 October 1993;accepted 23 November 1993)