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New ruthenium (III) and (II) complexes containing triphenyl-arsine, -phosphine and other ligands
INORG.
NUCL.
NEW
CHEM. LETTERS
V o l . . 8 , pp. 593-598,
RUTHENIUM
(HI) A N D
TRIPHENYL-ARSINE,
1972.
Pergamon Press.
(H) C O M P L E X E S
-PHOSPHINE
AND
Printed in Great Britain.
CONTAINING
OTHER
LIGANDS
E.S. Switkes, L. Ruiz-Ramirez, T.A. Stephenson and (in part) J. Sinclair Department of Chemistry, University of Edinburgh, Edinburgh, Scotland ( R e c e i v e d 21 March 1972)
There is an extensive chemistry
such as tertiary phosphines.
of r u t h e n i u m (II) c o m p o u n d s w i t h l i g a n d s
In particular, the complexes RuXz(PPh3) 3
or 4
(X = CI, Br) (I) are good starting materials for the synthesis of a range of ruthenium (II) c o m p o u n d s still containing triphenylphosphine (Z). In addition, such complexes as [Ru2CI3(PR3)6]CI
(3) and methanolic solutions of
ZRu5CIIz
(4) are excellent precursors for synthesising a wide range of
ruthenium (II) compounds. In contrast, relatively few ruthenium (HI) compounds containing tertiary monophosphines or arsines have been reported. Such compounds include the series m e r - R u X 3 L RuX3(MPh3)zS
3 (L = various tertiary phosphines and arsi~es) (5)
(M -- P, As; S = C H 3 O H
trans- [RuX4Lz]-
(I, 6), C H 3 N O z (7)), the anions
(X = CI, Br; L = P P h 3, A s P h 3, P M e z P h ,
PEt 3 (7)) and
the binuclear complexes [RuCI3(PR3)Z] Z and [RuzCI5(PR3)4] (R = Pr n, ]Bun) (8). in order that such a deficiency might be remedied, w e wish in this preliminary communication to report the results of a systematic study of the reactions of R u X 3 ( M P h 3 ) z S ( A ) with s o m e ligands containing carbon, nitrogen, sulphur and oxygen donor groups. Five different types of behaviour towards various ligands have been exhibited by A:-
593
594
1)
NEW RUTHENIUM(i!1) AND (ii) COMPLEXES
The labile
solvent ligand is readily
ruthenium
(III) c o m p o u n d s
displaced
RuX3(MPh3)zL
P h C H 2, C H 2 = CH), a c e t o n e
Vol. 8, No. 7
giving the six co-ordinated
[L = RCN,
(1)jT.H.F, M e 2 S O ,
(R = M e ,
CS2].
Ph,
The
infrared spectra (it.) of all the nitrile c o m p o u n d s contain a very w e a k ~CN
at c_~a 2 3 0 0 c m "I, 50 c m -I higher than in the free ligands which
suggest
that bonding occurs
dimethylsulphoxide spectra group
between
through
complexes 9OO-1OOO
a broad
band at ca
bonded CS 2 group.
-1
(4)).
1510 cm
-1
absorptions
suggestive The i.r.
indicating
(9).
-1
of these
in the i. r. sulphoxide
o f t h e CS 2 c o m p l e x e s the presence (ca
o r 1 1 2 0 c m "1)- l i n k a g e s
recrystallisation
The
of an O-bonded
No b a n d s d u e to t h i o c a r b o n y l
o r to r t - C S 2 ( c a 1OZO c m and attempted
have strong
cm
(cf. RuC13(MezSO)3
the nitrogen
complexes
contain
of a linearly 1280-1330
are present from
c m "1)
(lO)
benzene
results in loss of C S 2 and formation of R u X 3 ( M P h 3 ) 2. Examination of the far i.r. spectra of these c o m p o u n d s ( 4 O O - Z O O c m "I) indicates
a similar
configuration
configuration
I with trans
MPh 3 groups
is suggested.
X
halide
to t h a t o f t h e s t a r t i n g (vRuC1 347-299
X
materials
c m -1) (11) a n d t r a n s
L
.
Ph3M L
I
L
II
A and
L
III
Vol. 8, No. 7
z)
NEW RUTHENIUM ( l i d AND (!1) COMPLEXES
595
The solvent ligand and one MPh 3 group are displaced giving the six co-ordinate pyridine examples
(III) c o m p o u n d s ; R u X 3 ( M P h 3 ) L z [ L = M e z S ,
(1); L 2 = b i p y , o - p h e n ] of ruthenium
2, Z ' - b i p y r i d y l far i.r.
ruthenium
-1
ehe similarity
(III) c o m p o u n d s c o n t a i n i n g b o t h M P h 3 a n d
( o r 1, 1 0 - p h e n a n t h r o l i n e )
spectrum
a n d Z85 c m
Examination
of the
vRuC1 c_~a 3 3 0 c m
, s u g g e s t i n g c o n f i g u r a t i o n II w i t h a t r a n s - C 1 R u C 1 of the far i.r.
iII cannot be eliminated All the compounds*
methods).
groups.
of t h e s e c o m p o u n d s i n d i c a t e s
spectrum
of R u C 1 3 ( M P h 3 ) z S a l s o s u g g e s t s
of r u t h e n i u m
The latter are the first reported
to t h a t
c o n f i g u r a t i o n II a l t h o u g h , i n t h i s i n s t a n c e ,
in 1) a n d 2) h a v e m a g n e t i c
The 'H n.m.r,
grouping.
of RuC13(MPh3)(MezS)E
on t h e e v i d e n c e a t p r e s e n t
(III) s p i n - p a i r e d
-1
complexes
spectra
available.
moments
characteristic
( F a r a d a y a n d n. m . r .
solution
a r e t o o b r o a d e n e d to b e o b s e r v e d
except for RuC13(AsPh3)(MezS)z,
which shows resonances
T Z. 62 ~ r t h o 3 , T 3 . 3 4 [ m e t ~
methyl) shifted and broadened by the
presence
T4.60
of the paramagnetic
(T1.331par 4
ion.
T h e c o l o u r s of t h e c o m p o u n d s
vary widely, eg. RuC13(MPh3)zPhCH2CN
(green), RUCIB(MPhB)(MezS)z
(red), R u B r 3 ( M P h 3 ) z C H 3 C N
a detailed examination of their electronic spectra (50, O O O suggests that the lower energy absorptions (15, O O O
(purple) and - IO, O O O
- 30, O O O c m -I) arise
from X-~Ru charge transfer transitions. Similar results are found in compounds containing the [RuXz(bipy)z]+ ion (I2).
T h e corr_,pounds h a v e b e e n f u l l y c h a r a c t e r i s e d and molecular weight measurements.
c m -I)
by elemental
analyses
5'96
NEW RUTHENIUM (III) AND (II) COMPLEXES
In s o m e i n s t a n c e s , norbornadiene,
Vol. 8, No. 7
substitution is accompanied by reduction.
Thus, with
the complexes RuX2(MPh3)zC7H 8 are readily obtained.
F o r M = P , the s a m e c o m p o u n d s c a n be s y n t h e s i s e d f r o m RuXz(PPh3)3 or 4
and
C7H 8 (13).
With carbon monoxide, reaction
with RuC13(AsPh3)zCH3OH at room temperature
gives
trans- RuClz(eO)z(ASPh3) z (VCO1993 cm-I[cHzCIz]).
Comparison
with earlier triphenylphosphine work (I, 14) suggests configuration IV. C1
Ph 3 M
I
CO
CO
Cl
C1
h3
CI C1
C1
IV
V
CO
CO
MPh 3 C1 CO
C1
VI
VII
Recrystallisation 1999 c m
-1) (1)
f r o m h o t b e n z e n e g i v e s t h e ci___s i s o m e r
( c o n f i g u r a t i o n V).
Recrystallisation
from cold
C H z C 1 z / m e t h a n o l c a u s e s s e v e r a l b a n d s to d e v e l o p . appears,
w h i c h m a y b e due to t h e o t h e r t r a n s
(v2061 and
isomer
A b a n d a t 1943 c m VI.
-1
Vol. 8, No. 7
NEW RUTHENIUM (lid AND (11) COMPLEXES
In a d d i t i o n the g r o w t h of bands at Z036 c m
-1
and 1978 c m
597
-1
m a y be
a s s i g n e d to the o t h e r cis i s o m e r VII (VCO2038, 1983, 1967sh c m -1 f o r the p h o s p h i n e a n a l o g u e (14)).
T h e r e is no e v i d e n c e f o r RuC13(AsPh3)2CO
a l t h o u g h e a r l i e r w o r k e r s have b r i e f l y r e p o r t e d the s y n t h e s i s of R u B r 3 ( P P h 3 ) g C O . (6).
With b e n z y l c y a n i d e and M = P j r e a c t i o n u n d e r m i l d c o n d i t i o n s gives
RuX3(PPh3)2PhCH2CN.
However, under m o r e vigorous conditions,
reduction to R u X 2 ( P P h 3 ) y ( P h C H 2 C N ) 2
readily occurs. These compounds
can also be m a d e from RuXz(PPh3) 3 and benzyl cyanide (2).
4)
In s o m e i n s t a n c e s , NlPh 3 is c o m p l e t e l y d i s p l a c e d with or without r e d u c t i o n T h u s , r e a c t i o n o£ R u C 1 3 ( A s P h 3 ) z L (L = CH3OH, P h C H 2 C N ) with e x c e s s N a S 2 P P h Z g i v e s Ru(S2PPh2) 3 and p r o l o n g e d r e a c t i o n of R u X 3 ( A s P h 3 ) z C H 3 O H with p y r i d i n e g i v e s R u X z ( C 5 H s N ) 4 .
s)
F i n a l l y , the c h o i c e o£ s o l v e n t is an i m p o r t a n t c o n s i d e r a t i o n . R e a c t i o n of R u X 3 ( A s P h 3 ) 2 C H 3 O H with e x c e s s Z, Z ' - b i p y r i d y l in d i c h l o r o m e t h a n e gives RuX3(AsPh3)bipy.
H o w e v e r , in m e t h a n o l , p r e l i m i n a r y r e s u l t s i n d i c a t e
that p r o d u c t s c o n t a i n i n g the [RuXz(bipy)2] + c a t i o n a r e p r e f e r e n t i a l l y f o r m e d , w h e r e a s if the r e a c t i o n is c a r r i e d out in the p r e s e n c e of N a B P h 4, [ R u X z b i p y ( A s P h 3 ) Z ] B P h 4 can be i s o l a t e d . F u r t h e r s t u d i e s of t h e s e v e r s a t i l e c o m p l e x e s will be p r e s e n t e d in f u t u r e publications. A cknowled~ment
W e thank Johnson-Matthey Ltd for a loan of ruthenium trichloride, the National Institutes o£ Health (ES) and the National A. University of Mexico (l/R) for fellowships and the Department of Inorganic Chemistry, University of N e w c a s t l e f o r u s e of the F a r a d a y b a l a n c e .
598
NEW RUTHENIUM (lid AND (11) COMPLEXES
Vol. 8, No. 7
References
1.
T.A.
S t e p h e n s o n a n d G. W i l k i n s o n , J . I n o r g . N u c l . C h e m . ,
Z8, 945 (1966). 2.
For detailed references
see J.D.
G i l b e r t a n d G. W i l k i n s o n , J . C h e m .
S o c . (A), 1749 (1969).
3.
For detailed references see W . P .
Griffith, The Chemistry of the
R a r e r Platinum Metals, Interscience, London, 1967. 4.
J.D. Gilbert, D. R o s e and G. Wilkinson, J. C h e m . Soc. (A), Z765 (1970).
5.
J. Chatt, G.J. Leigh, D . M . P .
Mingos and R.J. Paske,
J. C h e m . Soc.(A), Z636 (1968) and references therein. 6.
L. Vaska, C h e m . and Ind., 14OZ (1961).
7.
T.A. Stephenson, J. C h e m . Soc.(A), 889 (1970).
8.
J.K. Nicholson, A n g e w . C h e m . lnternat. Edn. , 6
9.
R.A. Walton, Quart. Rev., 1_9126 (1965).
IO.
Z64 (1967).
See M . Kubota and G.R. Carey, J. Organometal Chem.,Z_4_491 (1970) and references therein.
ii.
M , S . Lupin and B.L. Sham', J . C h e m . Soc.(A), 741 (1968); J. Chart, G.J. Leigh and D . M . P .
Mingos, ibid, 1674 (1969).
12.
G.M.
Bryant and J.E. Fergusson, Aust. J . C h e m .
13.
S.D. Robinson and G. Wilkinson, J . C h e m . Soc(A), 3 O O (1966).
14.
B.R.
James and L.D. Markham,
373 (1971) and references therein.
Z_44 275, (1971).
Inorg. Nucl. Chem
Letters
7
NUCL.
NEW
CHEM. LETTERS
V o l . . 8 , pp. 593-598,
RUTHENIUM
(HI) A N D
TRIPHENYL-ARSINE,
1972.
Pergamon Press.
(H) C O M P L E X E S
-PHOSPHINE
AND
Printed in Great Britain.
CONTAINING
OTHER
LIGANDS
E.S. Switkes, L. Ruiz-Ramirez, T.A. Stephenson and (in part) J. Sinclair Department of Chemistry, University of Edinburgh, Edinburgh, Scotland ( R e c e i v e d 21 March 1972)
There is an extensive chemistry
such as tertiary phosphines.
of r u t h e n i u m (II) c o m p o u n d s w i t h l i g a n d s
In particular, the complexes RuXz(PPh3) 3
or 4
(X = CI, Br) (I) are good starting materials for the synthesis of a range of ruthenium (II) c o m p o u n d s still containing triphenylphosphine (Z). In addition, such complexes as [Ru2CI3(PR3)6]CI
(3) and methanolic solutions of
ZRu5CIIz
(4) are excellent precursors for synthesising a wide range of
ruthenium (II) compounds. In contrast, relatively few ruthenium (HI) compounds containing tertiary monophosphines or arsines have been reported. Such compounds include the series m e r - R u X 3 L RuX3(MPh3)zS
3 (L = various tertiary phosphines and arsi~es) (5)
(M -- P, As; S = C H 3 O H
trans- [RuX4Lz]-
(I, 6), C H 3 N O z (7)), the anions
(X = CI, Br; L = P P h 3, A s P h 3, P M e z P h ,
PEt 3 (7)) and
the binuclear complexes [RuCI3(PR3)Z] Z and [RuzCI5(PR3)4] (R = Pr n, ]Bun) (8). in order that such a deficiency might be remedied, w e wish in this preliminary communication to report the results of a systematic study of the reactions of R u X 3 ( M P h 3 ) z S ( A ) with s o m e ligands containing carbon, nitrogen, sulphur and oxygen donor groups. Five different types of behaviour towards various ligands have been exhibited by A:-
593
594
1)
NEW RUTHENIUM(i!1) AND (ii) COMPLEXES
The labile
solvent ligand is readily
ruthenium
(III) c o m p o u n d s
displaced
RuX3(MPh3)zL
P h C H 2, C H 2 = CH), a c e t o n e
Vol. 8, No. 7
giving the six co-ordinated
[L = RCN,
(1)jT.H.F, M e 2 S O ,
(R = M e ,
CS2].
Ph,
The
infrared spectra (it.) of all the nitrile c o m p o u n d s contain a very w e a k ~CN
at c_~a 2 3 0 0 c m "I, 50 c m -I higher than in the free ligands which
suggest
that bonding occurs
dimethylsulphoxide spectra group
between
through
complexes 9OO-1OOO
a broad
band at ca
bonded CS 2 group.
-1
(4)).
1510 cm
-1
absorptions
suggestive The i.r.
indicating
(9).
-1
of these
in the i. r. sulphoxide
o f t h e CS 2 c o m p l e x e s the presence (ca
o r 1 1 2 0 c m "1)- l i n k a g e s
recrystallisation
The
of an O-bonded
No b a n d s d u e to t h i o c a r b o n y l
o r to r t - C S 2 ( c a 1OZO c m and attempted
have strong
cm
(cf. RuC13(MezSO)3
the nitrogen
complexes
contain
of a linearly 1280-1330
are present from
c m "1)
(lO)
benzene
results in loss of C S 2 and formation of R u X 3 ( M P h 3 ) 2. Examination of the far i.r. spectra of these c o m p o u n d s ( 4 O O - Z O O c m "I) indicates
a similar
configuration
configuration
I with trans
MPh 3 groups
is suggested.
X
halide
to t h a t o f t h e s t a r t i n g (vRuC1 347-299
X
materials
c m -1) (11) a n d t r a n s
L
.
Ph3M L
I
L
II
A and
L
III
Vol. 8, No. 7
z)
NEW RUTHENIUM ( l i d AND (!1) COMPLEXES
595
The solvent ligand and one MPh 3 group are displaced giving the six co-ordinate pyridine examples
(III) c o m p o u n d s ; R u X 3 ( M P h 3 ) L z [ L = M e z S ,
(1); L 2 = b i p y , o - p h e n ] of ruthenium
2, Z ' - b i p y r i d y l far i.r.
ruthenium
-1
ehe similarity
(III) c o m p o u n d s c o n t a i n i n g b o t h M P h 3 a n d
( o r 1, 1 0 - p h e n a n t h r o l i n e )
spectrum
a n d Z85 c m
Examination
of the
vRuC1 c_~a 3 3 0 c m
, s u g g e s t i n g c o n f i g u r a t i o n II w i t h a t r a n s - C 1 R u C 1 of the far i.r.
iII cannot be eliminated All the compounds*
methods).
groups.
of t h e s e c o m p o u n d s i n d i c a t e s
spectrum
of R u C 1 3 ( M P h 3 ) z S a l s o s u g g e s t s
of r u t h e n i u m
The latter are the first reported
to t h a t
c o n f i g u r a t i o n II a l t h o u g h , i n t h i s i n s t a n c e ,
in 1) a n d 2) h a v e m a g n e t i c
The 'H n.m.r,
grouping.
of RuC13(MPh3)(MezS)E
on t h e e v i d e n c e a t p r e s e n t
(III) s p i n - p a i r e d
-1
complexes
spectra
available.
moments
characteristic
( F a r a d a y a n d n. m . r .
solution
a r e t o o b r o a d e n e d to b e o b s e r v e d
except for RuC13(AsPh3)(MezS)z,
which shows resonances
T Z. 62 ~ r t h o 3 , T 3 . 3 4 [ m e t ~
methyl) shifted and broadened by the
presence
T4.60
of the paramagnetic
(T1.331par 4
ion.
T h e c o l o u r s of t h e c o m p o u n d s
vary widely, eg. RuC13(MPh3)zPhCH2CN
(green), RUCIB(MPhB)(MezS)z
(red), R u B r 3 ( M P h 3 ) z C H 3 C N
a detailed examination of their electronic spectra (50, O O O suggests that the lower energy absorptions (15, O O O
(purple) and - IO, O O O
- 30, O O O c m -I) arise
from X-~Ru charge transfer transitions. Similar results are found in compounds containing the [RuXz(bipy)z]+ ion (I2).
T h e corr_,pounds h a v e b e e n f u l l y c h a r a c t e r i s e d and molecular weight measurements.
c m -I)
by elemental
analyses
5'96
NEW RUTHENIUM (III) AND (II) COMPLEXES
In s o m e i n s t a n c e s , norbornadiene,
Vol. 8, No. 7
substitution is accompanied by reduction.
Thus, with
the complexes RuX2(MPh3)zC7H 8 are readily obtained.
F o r M = P , the s a m e c o m p o u n d s c a n be s y n t h e s i s e d f r o m RuXz(PPh3)3 or 4
and
C7H 8 (13).
With carbon monoxide, reaction
with RuC13(AsPh3)zCH3OH at room temperature
gives
trans- RuClz(eO)z(ASPh3) z (VCO1993 cm-I[cHzCIz]).
Comparison
with earlier triphenylphosphine work (I, 14) suggests configuration IV. C1
Ph 3 M
I
CO
CO
Cl
C1
h3
CI C1
C1
IV
V
CO
CO
MPh 3 C1 CO
C1
VI
VII
Recrystallisation 1999 c m
-1) (1)
f r o m h o t b e n z e n e g i v e s t h e ci___s i s o m e r
( c o n f i g u r a t i o n V).
Recrystallisation
from cold
C H z C 1 z / m e t h a n o l c a u s e s s e v e r a l b a n d s to d e v e l o p . appears,
w h i c h m a y b e due to t h e o t h e r t r a n s
(v2061 and
isomer
A b a n d a t 1943 c m VI.
-1
Vol. 8, No. 7
NEW RUTHENIUM (lid AND (11) COMPLEXES
In a d d i t i o n the g r o w t h of bands at Z036 c m
-1
and 1978 c m
597
-1
m a y be
a s s i g n e d to the o t h e r cis i s o m e r VII (VCO2038, 1983, 1967sh c m -1 f o r the p h o s p h i n e a n a l o g u e (14)).
T h e r e is no e v i d e n c e f o r RuC13(AsPh3)2CO
a l t h o u g h e a r l i e r w o r k e r s have b r i e f l y r e p o r t e d the s y n t h e s i s of R u B r 3 ( P P h 3 ) g C O . (6).
With b e n z y l c y a n i d e and M = P j r e a c t i o n u n d e r m i l d c o n d i t i o n s gives
RuX3(PPh3)2PhCH2CN.
However, under m o r e vigorous conditions,
reduction to R u X 2 ( P P h 3 ) y ( P h C H 2 C N ) 2
readily occurs. These compounds
can also be m a d e from RuXz(PPh3) 3 and benzyl cyanide (2).
4)
In s o m e i n s t a n c e s , NlPh 3 is c o m p l e t e l y d i s p l a c e d with or without r e d u c t i o n T h u s , r e a c t i o n o£ R u C 1 3 ( A s P h 3 ) z L (L = CH3OH, P h C H 2 C N ) with e x c e s s N a S 2 P P h Z g i v e s Ru(S2PPh2) 3 and p r o l o n g e d r e a c t i o n of R u X 3 ( A s P h 3 ) z C H 3 O H with p y r i d i n e g i v e s R u X z ( C 5 H s N ) 4 .
s)
F i n a l l y , the c h o i c e o£ s o l v e n t is an i m p o r t a n t c o n s i d e r a t i o n . R e a c t i o n of R u X 3 ( A s P h 3 ) 2 C H 3 O H with e x c e s s Z, Z ' - b i p y r i d y l in d i c h l o r o m e t h a n e gives RuX3(AsPh3)bipy.
H o w e v e r , in m e t h a n o l , p r e l i m i n a r y r e s u l t s i n d i c a t e
that p r o d u c t s c o n t a i n i n g the [RuXz(bipy)2] + c a t i o n a r e p r e f e r e n t i a l l y f o r m e d , w h e r e a s if the r e a c t i o n is c a r r i e d out in the p r e s e n c e of N a B P h 4, [ R u X z b i p y ( A s P h 3 ) Z ] B P h 4 can be i s o l a t e d . F u r t h e r s t u d i e s of t h e s e v e r s a t i l e c o m p l e x e s will be p r e s e n t e d in f u t u r e publications. A cknowled~ment
W e thank Johnson-Matthey Ltd for a loan of ruthenium trichloride, the National Institutes o£ Health (ES) and the National A. University of Mexico (l/R) for fellowships and the Department of Inorganic Chemistry, University of N e w c a s t l e f o r u s e of the F a r a d a y b a l a n c e .
598
NEW RUTHENIUM (lid AND (11) COMPLEXES
Vol. 8, No. 7
References
1.
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Inorg. Nucl. Chem
Letters
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