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Copper catalysed O -phenylation of phenols and enols by pentavalent organobismuth compounds
Tetrahedron Letters,Vol.27,No.31,pp Printed in Great Britain
CCPPER
CATALYSED BY
Derek
H.R.
g-PHENYLATION
PENTAVALENT
Barton,
lnstitut
Jean-Pierre
de Chimie
..
-
The
Finet,
des
Khamsi
and
Naturelles,
Cif-sur-Yvette,
of
AND
ENOLS
COMPOUNDS
Jamal
Substances
-0-phenylation
0040-4039/86 $3.00 + .OO Pergamon Journals Ltd.
OF PHENOLS
ORCANOBISMUTH
91190
Abstract
3619-3622,1986
Clotilde
Pichon
C.N.R.S.
France
phenols
under
neutral
conditions
is strongly catalysed by copper salts and by copper by Bi” reagents powder, even at room temperature. Enolic systems are also subject to copper powder catalysis and give exclusively -0-phenylation.
Regioselective organobismuth the
reaction
The
reactivity
can
conditions.
’ s2
-0-arylation
various
Reaction
of
David
and
improved
reflux
with
them
the
1).
without
enols
choice
of
by
various
the
bismuth
pentavalent reagent
and
mechanistic
the
reactivity and
in
methylene
phenols
reaction
Following
studies
of
the
of
enolic
on
David
triphenylbismuth
and
Thieffry
diacetate
-1 with
compounds. dichloride
1
the
in
discovery
the
under presence
of a strong
reflux of
copper
yielded
a
base
salt
the
led
to
catalysis
in
Thieffry glycol reaction and a lesser catalysis in the -0-phenylation the effect of cupric diacetate on the phenylation of alcohols ,6 we studied
reaction
(Table
proper
phenols
whereas
Addition
phenols.
ture
1
of
examined
among
and
phenols by
can be selectively performed. -0- or -C-phenylation diacylates with phenols and enols was not extensively
course
derivatives.’
-0-phenylation of
we
,3’4
many
obtained
Thus,
the
derivatives,
-C-phenylated the
in
substrates,’
-0-phenyl
of be
of triphenylbismuth
However
studied.’ glycol
phenylation
reagents
An
of
copper
rate
in such
optimum
yield
diacetate
CU(OAC)~
a way
that
was
obtained
the
in
reaction after
catalytic could
1 hr,
amount be run
instead
of
(0.1
at
room tempera-
23 hours
catalyst. Ph4BiOCOCF3
1
2
/
3
R’
0
0 &
R2
-4 2
R' =R2
6
R’
3619
=H
R’=Ph,R’=H = H,
R2
= Ph
equiv.)
under
3620
Table
1.
Phenylation
Reaction Time (hr)
Entry 1
23’
2
24’
3
1
4
24
5
24
6
4
of Phenol
-4 with
Catalyst (eq. 1
Triphenylbismuth
BTEK b (eq.)
Diacetatea
2
5
-6
0
14
86
0
1.2
60
trace
CU(OAC)~,
(0.1)
0
15
77
0
CU(OAC)~,
(0.1)
0
13
80
0
CU(OAC)~,
(0.1)
1.2
34
53
6
0
90
0
cu.
(0.1)
0
20
a) All reactions performed with 1 (1.2 eq.) in CH Cl under argon at room temperature unless specified otherwise. b) BTMG2= -i;-t-butyl-I\l’,N’,N”,N_“c) Reaction performed under reflux. tetramethylguanidine.
In the
reaction
(Entry
5)
mostly
modification
of
the
give
: addition
conditions
room temperature then
performed
poor
yield
was
not
under
basic
the CJ-phenyl
reaction
and
system
of metallic
in CH2C12 on
conditions,
a series
with of
made
copper
original
although possible
powder
stirring
(Table did
had
not the
regioselectivity
in moderate a
(0.1
yielded
phenols
2,4,6-tri-t-butylphenol 98.5% Pure copper
critical.
ether,
the
high equiv.)
react. same
Only The effect
(53%). reaction
to a mixture
-5 in 90% after 2).
yield
yielding
was
1 hr.
of
The
reversed
to
A further under
mild
1 and
-4 at
reaction
was
2,4-di-t-butylphenol
gave
purity
copper
powder
Label
99.995%
as Aldrich
of the Gold
copper.
Table
2.
Metallic
-0-Phenylation ArOH
+ -1 + Cu
9 16 TT Tz n
n
i-5 -iG 7 T8 -
->
OH
Catalysed a.b
of Phenols.
-7
-7
Copper
Ar-OPh -10
-8
Reaction Time (hr) 5 5 24 3 4 5 3 24 5 15
OH
OH
OH
OH
8 84 88 73 67 90 80 26 0 90 97
Ale0
a) Reaction conditions : 1 (1.2 eq.), CU (0.1 eq.), CH Cl , room temperature, b) AlI hew compounds were under argon. fully characterised by analytical and spectroscopic data.
OMe -15
OH
OH
C02Me
-17
-18
-16
a
3621
The of
effect
-4 and the
of copper
with
phenols’
-9 in benzene
corresponding
a high
Table
yield
at
room
-0-phenyl
(Table
Copper
3.
salts
appeared
tetraphenylbismuth
also
in the
previously
trifluoroacetate
temperature
gave
after
However,
ethers.
24 hours
addition
described
Reaction
3.
poor
of 0.1
Salt
Catalysis
of the
Reaction
of Phenol
Unreacted phenol (8)
4 -
0.1
9 -
0
36
50
9 -
0.1
12
80
All reactions for 24 hrs,
Substrate
60
Catalysis
klethoda
with
3a
27
3 (1.2 -
of the
20
A
in benzene
Phenylation
Reaction Time (hr)
A
eq.)
at
Reaction
room temperature
of Enols.
Catalyst (eq. 1
0-phenyl Fther (%)
S.M. (8)
I-9,
(56)
2,
(27)
l-9, (551
2,
(40)
22,
23,
(45)
40
Cu(OAc12.
-22 -22
B
24
cu.
(0.1)
C
24
cu.
(0.1)
2,
(aa)
-24
n
4
cu.
(0.1)
25,
(70)
-24
B
4
cu,
(0.1)
2,
(96)
3 (1.2
equiv.),
C: 1 (2 equiv.),
-19R=H -20 R = Ph
of
gave
a5
performed with under argon.
Copper
-19 -19
a)‘A:
yields
Phenyl ether (8)
0
Entry
phenols
of Cu(OAc12
g-Phenylation
4 -
4.
with
3).
Cu(OAc12 (eq.)
Table
-3
to moderate
equiv.
Phenol
a)
-0-phenylation
of
C6H6,
CH2C12,
5ooc;
B:
2 (1 equiv.),
room temperature;
(0.1)
CH2C12,
D: _1 (1 equiv.
),
(22)
room temperature: CH2C12,
room temperature.
3622
0
-23
Enolic not
have
systems a major
However,
21.
which
reacted
7
yields. changed
the
the -0-phenyl to
A
oxidation
is
the
addition
of Bi
and V
compounds
behaviour
the
to phenols.2 of -19
of copper
diacetate
-1
derivative
-25.
effected
or
by by
Cupric
(Table
Dimedone powder
uncatalysed
disulphides
of copper
mechanism
R = Ph
0-phenylation
presence
than
thiols
scope
reactions
with
R=H
-20 was observed.
-23 in the
of
similar
the
derivative
oxidation
by
The
on
faster
smoothly
to furnish
arylation
effect
markedly
very
The
a similar
derivative
was
catalysis,
show catalytic
no -C-phenyl
to its -0-phenyl 4)
-24 -25
(Table
reagent
4,
The 2,
did 1 and
entries
the
-24 distinct
with
carbonate
-2 and
3 and
diosphenol
again
triphenylbismuth diacetate
acetate
entries
-22 was also converted
reaction.2
the
the
4,
gives
reaction
high is
not
powder.
of
this
catalysis
is currently
by
under
metallic
study
and
copper
will
in
the
be reported
-0-arylation
in full
in due
J.-P.
Finet,
course. REFERENCES
1.
2.
3.
D.H.
R.
N.Y.
Barton,
D.J.
Lester,
W.B.
sot.,
Perkin
Trans.
D.H.R.
Barton,
M.T.B.
Papouta,
S.
David
Chem _., 4.
D.H.R.
5.
D.H.R.
and
48,
Bhatnagar, Motherwell, I,
2657
J.-C.
441
S.P.
Blazejewski,
M.T.B.
Papoula,
B.
and
Charpiot,
S.P.
Stanforth,
J.
Chem.
(1985).
Blazejewski,
and A.
J.-C.
B.
Stanforth,
Thieffry,
J.
Charpiot, Chem.
Tetrahedron
J.rP.
Sot.,
Lett.,
z,
Finet,
Perkin 2885,
W.B.
Trans. 5063
Motherwell, I,
2667
(1981);
(1985).
J.
Org.
(19831.
Barton,
J.-P.
Finet,
J.-P.
Finet,
and
C.
Pichon,
J.
and
C.
Pichon,
in preparation:
Chem. kc.,
Chem.
Commun.,
65
(19861. Barton,
Doctorat 6.
V.A.
7.
dIEtat,
University
Dodonov,
A.V.
(1984):
Chem.
Abs.,
D.H.R.
Barton,
Tetrahedron,
(Received
37,
J.P.
Gushchin, E,
T.G.
Pichon,
These
de
Brilkina,
Zh.
Obshch.
Khim.,
2,
2157
(1985).
D.J.
Lester,
73 (1981).
2 June
C.
1985.
and
45543~
Kitchin,
Suppl.1,
in France
of Orsay,
1986)
W.B.
Motherwell,
and
M.T.
B.
Papoula,
CCPPER
CATALYSED BY
Derek
H.R.
g-PHENYLATION
PENTAVALENT
Barton,
lnstitut
Jean-Pierre
de Chimie
..
-
The
Finet,
des
Khamsi
and
Naturelles,
Cif-sur-Yvette,
of
AND
ENOLS
COMPOUNDS
Jamal
Substances
-0-phenylation
0040-4039/86 $3.00 + .OO Pergamon Journals Ltd.
OF PHENOLS
ORCANOBISMUTH
91190
Abstract
3619-3622,1986
Clotilde
Pichon
C.N.R.S.
France
phenols
under
neutral
conditions
is strongly catalysed by copper salts and by copper by Bi” reagents powder, even at room temperature. Enolic systems are also subject to copper powder catalysis and give exclusively -0-phenylation.
Regioselective organobismuth the
reaction
The
reactivity
can
conditions.
’ s2
-0-arylation
various
Reaction
of
David
and
improved
reflux
with
them
the
1).
without
enols
choice
of
by
various
the
bismuth
pentavalent reagent
and
mechanistic
the
reactivity and
in
methylene
phenols
reaction
Following
studies
of
the
of
enolic
on
David
triphenylbismuth
and
Thieffry
diacetate
-1 with
compounds. dichloride
1
the
in
discovery
the
under presence
of a strong
reflux of
copper
yielded
a
base
salt
the
led
to
catalysis
in
Thieffry glycol reaction and a lesser catalysis in the -0-phenylation the effect of cupric diacetate on the phenylation of alcohols ,6 we studied
reaction
(Table
proper
phenols
whereas
Addition
phenols.
ture
1
of
examined
among
and
phenols by
can be selectively performed. -0- or -C-phenylation diacylates with phenols and enols was not extensively
course
derivatives.’
-0-phenylation of
we
,3’4
many
obtained
Thus,
the
derivatives,
-C-phenylated the
in
substrates,’
-0-phenyl
of be
of triphenylbismuth
However
studied.’ glycol
phenylation
reagents
An
of
copper
rate
in such
optimum
yield
diacetate
CU(OAC)~
a way
that
was
obtained
the
in
reaction after
catalytic could
1 hr,
amount be run
instead
of
(0.1
at
room tempera-
23 hours
catalyst. Ph4BiOCOCF3
1
2
/
3
R’
0
0 &
R2
-4 2
R' =R2
6
R’
3619
=H
R’=Ph,R’=H = H,
R2
= Ph
equiv.)
under
3620
Table
1.
Phenylation
Reaction Time (hr)
Entry 1
23’
2
24’
3
1
4
24
5
24
6
4
of Phenol
-4 with
Catalyst (eq. 1
Triphenylbismuth
BTEK b (eq.)
Diacetatea
2
5
-6
0
14
86
0
1.2
60
trace
CU(OAC)~,
(0.1)
0
15
77
0
CU(OAC)~,
(0.1)
0
13
80
0
CU(OAC)~,
(0.1)
1.2
34
53
6
0
90
0
cu.
(0.1)
0
20
a) All reactions performed with 1 (1.2 eq.) in CH Cl under argon at room temperature unless specified otherwise. b) BTMG2= -i;-t-butyl-I\l’,N’,N”,N_“c) Reaction performed under reflux. tetramethylguanidine.
In the
reaction
(Entry
5)
mostly
modification
of
the
give
: addition
conditions
room temperature then
performed
poor
yield
was
not
under
basic
the CJ-phenyl
reaction
and
system
of metallic
in CH2C12 on
conditions,
a series
with of
made
copper
original
although possible
powder
stirring
(Table did
had
not the
regioselectivity
in moderate a
(0.1
yielded
phenols
2,4,6-tri-t-butylphenol 98.5% Pure copper
critical.
ether,
the
high equiv.)
react. same
Only The effect
(53%). reaction
to a mixture
-5 in 90% after 2).
yield
yielding
was
1 hr.
of
The
reversed
to
A further under
mild
1 and
-4 at
reaction
was
2,4-di-t-butylphenol
gave
purity
copper
powder
Label
99.995%
as Aldrich
of the Gold
copper.
Table
2.
Metallic
-0-Phenylation ArOH
+ -1 + Cu
9 16 TT Tz n
n
i-5 -iG 7 T8 -
->
OH
Catalysed a.b
of Phenols.
-7
-7
Copper
Ar-OPh -10
-8
Reaction Time (hr) 5 5 24 3 4 5 3 24 5 15
OH
OH
OH
OH
8 84 88 73 67 90 80 26 0 90 97
Ale0
a) Reaction conditions : 1 (1.2 eq.), CU (0.1 eq.), CH Cl , room temperature, b) AlI hew compounds were under argon. fully characterised by analytical and spectroscopic data.
OMe -15
OH
OH
C02Me
-17
-18
-16
a
3621
The of
effect
-4 and the
of copper
with
phenols’
-9 in benzene
corresponding
a high
Table
yield
at
room
-0-phenyl
(Table
Copper
3.
salts
appeared
tetraphenylbismuth
also
in the
previously
trifluoroacetate
temperature
gave
after
However,
ethers.
24 hours
addition
described
Reaction
3.
poor
of 0.1
Salt
Catalysis
of the
Reaction
of Phenol
Unreacted phenol (8)
4 -
0.1
9 -
0
36
50
9 -
0.1
12
80
All reactions for 24 hrs,
Substrate
60
Catalysis
klethoda
with
3a
27
3 (1.2 -
of the
20
A
in benzene
Phenylation
Reaction Time (hr)
A
eq.)
at
Reaction
room temperature
of Enols.
Catalyst (eq. 1
0-phenyl Fther (%)
S.M. (8)
I-9,
(56)
2,
(27)
l-9, (551
2,
(40)
22,
23,
(45)
40
Cu(OAc12.
-22 -22
B
24
cu.
(0.1)
C
24
cu.
(0.1)
2,
(aa)
-24
n
4
cu.
(0.1)
25,
(70)
-24
B
4
cu,
(0.1)
2,
(96)
3 (1.2
equiv.),
C: 1 (2 equiv.),
-19R=H -20 R = Ph
of
gave
a5
performed with under argon.
Copper
-19 -19
a)‘A:
yields
Phenyl ether (8)
0
Entry
phenols
of Cu(OAc12
g-Phenylation
4 -
4.
with
3).
Cu(OAc12 (eq.)
Table
-3
to moderate
equiv.
Phenol
a)
-0-phenylation
of
C6H6,
CH2C12,
5ooc;
B:
2 (1 equiv.),
room temperature;
(0.1)
CH2C12,
D: _1 (1 equiv.
),
(22)
room temperature: CH2C12,
room temperature.
3622
0
-23
Enolic not
have
systems a major
However,
21.
which
reacted
7
yields. changed
the
the -0-phenyl to
A
oxidation
is
the
addition
of Bi
and V
compounds
behaviour
the
to phenols.2 of -19
of copper
diacetate
-1
derivative
-25.
effected
or
by by
Cupric
(Table
Dimedone powder
uncatalysed
disulphides
of copper
mechanism
R = Ph
0-phenylation
presence
than
thiols
scope
reactions
with
R=H
-20 was observed.
-23 in the
of
similar
the
derivative
oxidation
by
The
on
faster
smoothly
to furnish
arylation
effect
markedly
very
The
a similar
derivative
was
catalysis,
show catalytic
no -C-phenyl
to its -0-phenyl 4)
-24 -25
(Table
reagent
4,
The 2,
did 1 and
entries
the
-24 distinct
with
carbonate
-2 and
3 and
diosphenol
again
triphenylbismuth diacetate
acetate
entries
-22 was also converted
reaction.2
the
the
4,
gives
reaction
high is
not
powder.
of
this
catalysis
is currently
by
under
metallic
study
and
copper
will
in
the
be reported
-0-arylation
in full
in due
J.-P.
Finet,
course. REFERENCES
1.
2.
3.
D.H.
R.
N.Y.
Barton,
D.J.
Lester,
W.B.
sot.,
Perkin
Trans.
D.H.R.
Barton,
M.T.B.
Papouta,
S.
David
Chem _., 4.
D.H.R.
5.
D.H.R.
and
48,
Bhatnagar, Motherwell, I,
2657
J.-C.
441
S.P.
Blazejewski,
M.T.B.
Papoula,
B.
and
Charpiot,
S.P.
Stanforth,
J.
Chem.
(1985).
Blazejewski,
and A.
J.-C.
B.
Stanforth,
Thieffry,
J.
Charpiot, Chem.
Tetrahedron
J.rP.
Sot.,
Lett.,
z,
Finet,
Perkin 2885,
W.B.
Trans. 5063
Motherwell, I,
2667
(1981);
(1985).
J.
Org.
(19831.
Barton,
J.-P.
Finet,
J.-P.
Finet,
and
C.
Pichon,
J.
and
C.
Pichon,
in preparation:
Chem. kc.,
Chem.
Commun.,
65
(19861. Barton,
Doctorat 6.
V.A.
7.
dIEtat,
University
Dodonov,
A.V.
(1984):
Chem.
Abs.,
D.H.R.
Barton,
Tetrahedron,
(Received
37,
J.P.
Gushchin, E,
T.G.
Pichon,
These
de
Brilkina,
Zh.
Obshch.
Khim.,
2,
2157
(1985).
D.J.
Lester,
73 (1981).
2 June
C.
1985.
and
45543~
Kitchin,
Suppl.1,
in France
of Orsay,
1986)
W.B.
Motherwell,
and
M.T.
B.
Papoula,