One-pot syntheses of alcohols from olefins through Co/Ru tandem catalysis

Article abstract of DOI:10.1016/j.molcata.2007.02.030

The one-pot synthesis of cyclohexylmethanol from cyclohexene has been realized using a tandem catalytic system formed by the Co₂(CO)₈ complex for hydroformylation and different [Ru(CO)₂(PPh₃)X₂]₂ (X: Cl, Br, I) complexes for hydrogenation. The sole ruthenium(II) complexes [Ru(CO)₂(PPh₃)X₂]₂ (X: Cl, Br, I) are also able to synthesize cyclohexylmethanol from cyclohexene but a large part of the olefin is hydrogenated to alkane. Furthermore the sole ruthenium complexes are able to hydrogenate aldehydes to the corresponding alcohols even in the presence of carbon monoxide. The tandem catalytic system (Co-Ru) allows for the syntheses of several primary alcohols from the corresponding olefins with a total conversion and a very high selectivity (up to 97%).

Full text of DOI:10.1016/j.molcata.2007.02.030

Journal of Molecular Catalysis A: Chemical 271 (2007) 80–85
One-pot syntheses of alcohols from olefins through
Co/Ru tandem catalysis
Piero Frediani∗, Paolo Mariani, Luca Rosi, Marco Frediani, Alessandro Comucci
Department of Organic Chemistry, University of Florence, Via della Lastruccia, 13, 50019 Sesto Fiorentino, Firenze, Italy
Received 11 January 2007; received in revised form 19 February 2007; accepted 20 February 2007
Available online 24 February 2007
Abstract
The one-pot synthesis of cyclohexylmethanol from cyclohexene has been realized using a tandem catalytic system formed by the Co2(CO)8
complex for hydroformylation and different [Ru(CO)2(PPh3)X2]2 (X: Cl, Br, I) complexes for hydrogenation. The sole ruthenium(II) complexes
[Ru(CO)2(PPh3)X2]2 (X: Cl, Br, I) are also able to synthesize cyclohexylmethanol from cyclohexene but a large part of the olefin is hydrogenated
to alkane. Furthermore the sole ruthenium complexes are able to hydrogenate aldehydes to the corresponding alcohols even in the presence of
carbon monoxide. The tandem catalytic system (Co-Ru) allows for the syntheses of several primary alcohols from the corresponding olefins with
a total conversion and a very high selectivity (up to 97%).
© 2007 Elsevier B.V. All rights reserved.
Keywords: Alcohol; Alkene; Hydroformylation; Tandem catalysis
1. Introduction
formation of alcohol but the yields are not so high due to the
hydrogenation of alkene in a large extent.
Primary alcohols are an important class of products that
founds application as intermediates in organic synthesis for
agrochemicals, detergents, pharmaceuticals or directly used as
solvent or oxygen containing compounds in fuel blending.
Alcohols may be synthesised from olefins through a two
steps process [1]. In the first one the olefin is transformed into
the corresponding aldehyde (hydroformylation process) and in
the second step aldehyde is hydrogenated to alcohol. However
the possibility to realize the one-pot syntheses of primary alco-
hols is actually very attracting [2]. Several papers are reported
concerning the direct synthesis of alcohols from olefins both in
homogeneous or heterogeneous phase using Co, Ru, Rh, Pd cat-
alysts [3–7]. The main problem concerning the one step reaction
is the parallel hydrogenation of alkene and sometimes the severe
reaction conditions required.
2. Experimental
2.1. Instruments and materials
A Shimadzu GC14 chromatograph was equipped with two
FID detectors, and a 2 m packed columns filled with PPG
monostearate supported on chromosorb as stationary phase. The
response factors of reagents and products were evaluated for
quantitativeanalyses. Theidentityoftheproductswasconfirmed
by GC-MS using a Shimadzu apparatus (GCMS-QP5050A)
equippedwithacapillarycolumnSPTM-1(length30 m, diameter
0.25 mm, film thickness 0.1 ␮m).
Elemental analyses were performed with a Perkin-Elmer
Analyzer model 2400 Series II CHNS/O.
In this paper we report on the one-pot syntheses of alco-
hols from olefins using the tandem catalytic system [Ru(CO)2
(PPh3)X2]2/Co2(CO)8 (X: Cl, Br, I). The sole [Ru(CO)2
(PPh3)X2]2 (X: Cl, Br, I) complexes also catalyze the one-pot
IR spectra were recorded with a Perkin-Elmer mod. 1760
FTIR spectrometer.
1H, 13C and 31P NMR spectra were recorded using a Varian
VXR300 spectrometer operating at 299.987 MHz for 1H NMR,
at 75.429 MHz for 13C NMR and at 121.421 MHz for 31P NMR,
using solutions of appropriate solvents. Residual hydrogens of
solvents were used as internal standard for 1H NMR, the carbon
atoms of the solvent for 13C NMR, and H3PO4 (85%) as external
∗
Corresponding author. Tel.: +39 055 457 3522; fax: +39 055 457 3531.
E-mail address: piero.frediani@unifi.it (P. Frediani).
1381-1169/$ – see front matter © 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.molcata.2007.02.030

P. Frediani et al. / Journal of Molecular Catalysis A: Chemical 271 (2007) 80–85
81
Table 1
Spectroscopic data of mononuclear (1)–(3) and binuclear (5)–(7) ruthenium complexes
Complex
IR
NMR (ppm)
Solvent ν CO (cm−1
)
Solvent 31P
1H
13C
[Ru(CO)2(PPh3)Cl2]2 CH2Cl2 2059 (s), 1996 (s)
[Ru(CO)2(PPh3)Br2]2 CH2Cl2 2058 (s), 1996 (s)
CDCl3
CDCl3
17.04 8.2–7.8, 7.7–7.5
13.12 7.7–7.2
CO: 207.20 (s); Ph: 134.50–128.00
CO: 208.50 (s); Ph: 134.44 (d, Ci, JCP 10.4 Hz);
133.35 (s, Cp); 132.64 (d, Cm, JCP 10.7 Hz); 129.15
(d, Co, JCP 12.4 Hz)
[Ru(CO)2(PPh3)I2]2
CH2Cl2 2056 (s), 1996 (s)
CDCl3
7.68 7.8–7.2
CO: 207.10 (s); Ph: 134.62 (d, Ci, JCP 8.9 Hz);
132.65 (s, Cp); 131.96 (d, Cm, JCP 10.0 Hz); 128.78
(d, Co, JCP 12.1 Hz)
Ru(CO)3(PPh3)Cl2
Ru(CO)3(PPh3)Br2
C6D6
C6D6
2129 (s), 2072 (vs), 2034 (s) C6D6
2128 (s), 2071(s), 2036 (vs) C6D6
16.28 8.25–8.10; 7.05–6.8
CO: 192.50 (s), 185.80 (s); Ph: 135.00–128.00
11.68 7.60–7.35; 7.03–6.88 CO: 196.40 (s), 187.20 (s); Ph: 134.15 (d, Ci, JCP
9.4 Hz); 133.50 (s, Cp); 132.64 (d, Co, JCP 8.3 Hz);
129.60 (d, Cm, JCP 21.4 Hz)
Ru(CO)3(PPh3) I2
C6D6
2113 (s), 2062 (vs), 2035 (s) C6D6
4.29 7.50–7.30; 6.96–6.80 CO: 196.50 (s), 186.80 (s); Ph: 134.34 (d, Ci, JCP
9.1 Hz); 133.03 (s, Cp); 132.14 (d, Co, JCP 10.6 Hz);
129.01 (d, Cm, JCP 13.7 Hz)
standard for 31P NMR (signals reported as positive downfield to
the standard). 13C and 31P NMR spectra were acquired using a
broad band decoupler.
All manipulations were routinely carried out under a nitrogen
atmosphere using standard Schlenk techniques.
in Table 1. Elemental analysis for C21H15Cl2O3PRu was: % C
48.57 (48.67), % H 2.87 (2.92), % Cl 13.77 (13.68). The IR
bands are in agreement with those reported by Johnson et al.
[10] for the same product obtained through another procedure.
Hydroformylations were performed in a stainless steel high
pressure autoclave (125 ml) equipped with a stopper and a
manometer, heated in an oil bath kept at the required temper-
ature ( 1 ◦C). In the course of the reaction the total pressure of
the reaction was kept constant supplying the appropriate amount
of CO/H2 mixture from a high pressure cylinder.
Benzene and toluene were deoxygenated and dried by
refluxing under nitrogen atmosphere and distilling over
sodium/potassium amalgam.
2.2.2. Synthesis of Ru(CO)3(PPh3)Br2 (6)
A solution of [Ru(CO)2(PPh3)Br2]2 (0.5 g, 0.43 mmol) in
toluene (20 ml) was introduced in the autoclave, the vessel pres-
surized to 115 bar with CO and the reactor kept in a thermostated
oil bath, rocked and heated at 100 ◦C for 5 h. The autoclave was
cooled, the gas vented and a light yellow solution collected. Pen-
tane was added and 0.515 g (0.85 mmol) of Ru(CO)3(PPh3)Br2
(6) was precipitated as light yellow crystals with 98% yield.
A cyclohexane solution of the product show IR bands, in the
2100–1800 cm−1 region, at 2036 (m), 2073 (s), 2128 (m), while
the IR, the 1H, 13C and 31P NMR signals, in C6D6, are reported
in Table 1. Elemental analysis for C21H15Br2O3PRu was: % C
41.30 (41.54), % H 2.48 (2.49), % Br 26.29 (26.32). The IR
bands are in agreement with those reported by Johnson et al.
[10] for the same product obtained through another procedure.
Cyclohexene, pent-1-ene, oct-1-ene, 4-methylpent-1-ene
were commercial products, purified by elution on an Al2O3
column, then dried by refluxing and distilling on Na.
2.2. Synthesis of complexes
The following complexes were prepared according to the
literature: [Ru(CO)2(PPh3)Cl2]2 (1) [8], [Ru(CO)2(PPh3)Br2]2
(2) [8], [Ru(CO)2(PPh3)I2]2 (3) [8], Co2(CO)8 (4) [9]. Their
spectroscopic characteristics are reported in Table 1.
The following complexes were also synthesised as reference
compounds.
2.2.3. Synthesis of Ru(CO)3(PPh3)I2 (7)
A solution of [Ru(CO)2(PPh3)I2]2 (0.5 g, 0.37 mmol) in
toluene (20 ml) was introduced in the autoclave, the vessel was
pressurized to 115 bar with CO and the reactor kept in a ther-
mostated oil bath, rocked and heated at 100 ◦C for 5 h. The
autoclave was cooled, the gas vented and a yellow lemon solu-
tion collected. Pentane was added and 0.512 g (0.73 mmol) of
Ru(CO)3(PPh3)I2 (7) was precipitated as yellow-lemon crystals
with 98% yield. A cyclohexane solution of the product show
IR bands, in the 2100–1800 cm−1 region, at 2037 (m), 2060
2.2.1. Synthesis of Ru(CO)3(PPh3)Cl2 (5)
A solution of [Ru(CO)2(PPh3)Cl2]2 (0.5 g, 0.51 mmol) in
toluene (20 ml) was introduced in the autoclave, the vessel pres-
surized to 115 bar with CO and the reactor kept in a thermostated
oil bath, rocked and heated at 100 ◦C for 5 h. The autoclave
was cooled, the gas vented and a white solution collected. Pen-
tane was added and 0.52 g (1.00 mmol) of Ru(CO)3(PPh3)Cl2
(5) was precipitated as yellow-lemon crystals with 98% yield.
A cyclohexane solution of the product show IR bands, in the
2100–1800 cm−1 region, at 2033 (m), 2075 (s), 2133 (m), while
the IR, the 1H, 13C and 31P NMR signals, in C6D6, are reported
1
(s), 2116 (m), while the IR, the H, 13C and 31P NMR sig-
nals, in C6D6, are reported in Table 1. Elemental analysis for
C21H15I2O3PRu was: % C 35.90 (35.97), % H 2.15 (2.16), % I
35.50 (35.20). The IR bands are in agreement with those reported
by Johnson et al. [10] for the same product obtained through
another procedure.

82
P. Frediani et al. / Journal of Molecular Catalysis A: Chemical 271 (2007) 80–85
Table 2
Hydroformylation of cyclohexene in the presence of [Ru(CO)2(PPh3)X2]2 (X = Cl, Br, I) (1)–(3) as catalyst
Run no.
X
pH2 (bar) p(CO) (bar) Induction time Reaction time
Conversion (%) Reaction products composition (%)
Alkane Alcohol Aldehyde Othersb
Selectivitya
(%)
(min)
(min)
1
2
3
4
5
6
Cl 101
Br 101
9
9
9
20
20
20
52
–
52
45
55
60
360
360
360
655
655
655
52.8
90.3
26.3
87.5
96.5
59.0
67.6
59.5
63.6
39.0
44.8
32.5
29.2
38.8
32.5
59.0
51.7
60.0
2.0
<1.0
2.8
0.4
0.4
1.2
0.7
1.1
1.6
3.1
5.0
33.2
40.9
36.4
61.0
55.2
67.5
I
101
Cl 110
Br 110
I
110
2.5
Cyclohexene 98.7 mmol; toluene 30 ml; catalyst 17.3 mmol; T 150 ◦C.
a
Selectivity: mol hydroformylation products/mol total products.
Others: C6H11CH(OCH2C6H11)2.
b
Table 3
Hydrogenation of cyclohexylformaldehyde in the presence of [Ru(CO)2
(PPh3)X2]2 (X = Cl, Br, I) (1)–(3) as catalyst
Run no.
X
Induction time (min)
Conversion (%)
Selectivitya
(molar ratio)
7
8
9
Cl
Br
I
28
48
47
79.3
27.6
27.0
96.5
86.0
87.0
Cyclohexylformaldehyde 50.0 mmol; toluene 30 ml; catalyst 11.5 mmol; T
120 ◦C; p(H2) 102 bar; p(CO) 19 bar, reaction time 20 min.
Scheme 1.
a
Selectivity: mol alcohol/mol products.
2.3. Hydroformylation
3. Results and discussion
A typical experiment is described: the same procedure was
employed for all catalysis. The data collected are reported in
Tables 2–6.
3.1. Hydroformylation of cyclohexene in the presence of
(1)–(3) as catalysts
The catalyst was introduced into the autoclave, the vessel
closed, air evacuated and a solution containing the solvent and
the substrate introduced by suction. The autoclave was pres-
surized with CO and H2 at the desired pressure and the reactor
placed in a thermostated oil bath. When the pressure was reduced
of 4 bar, the same amount of gas mixture was reintroduced in
the reactor from a high pressure cylinder containing the same
gas mixture.
When the absorption of the gas was ceased or after a prefixed
time, the autoclave was cooled to room temperature, and the
gas vented. The solution was collected, analyzed by GC and the
products identified through GC-MS technique.
The catalytic activity of the ruthenium complexes (1)–(3) was
tested at 150 ◦C using a hydrogen pressure among 100–110 bar
and a CO pressure of 9 or 20 bar. Cyclohexene was chosen as
substrate to avoid problems due to the formation of isomers
(Table 2).
The main products were cyclohexylmethanol and cyclo-
hexane together with low amount of cyclohexylformaldehyde
(Scheme 1). Trace of the acetal resulting from the reaction
between the alcohol and the aldehyde was also detected. The
alcohol/alkane ratio is lower than 1 using a p(CO) of 9 bar
(0.43–0.65) while it is increased to 1.51–1.84 working in the
presence of 20 bar of CO. Increasing the CO pressure the
Table 4
Hydroformylation of cyclohexene in the presence of [Ru(CO)2(PPh3)X2]2 (X = Cl, Br, I) (1)–(3) and Co2(CO)8 (4) as catalysts
Run no.
X
Co/Ru
(molar ratio)
p(H2) (bar)
p(CO) (bar)
Induction
time (min)
Reaction
timea (min)
Reaction products composition (%)
Selectivityb (%)
Alkane
Alcohol
Aldehyde
10
11
12
13
14
Cl
Br
I
Cl
Cl
2.5
2.5
2.5
5
107
107
107
107
101
11
11
11
11
42
14
13
13
12
20
206
120
101
320
310
12.0
21.0
13.5
10.0
4.0
85.0
78.1
83.0
85.0
89.0
3.0
0.9
2.5
5.0
7.0
88.0
79.0
85.5
90.0
96.0
3
Cyclohexene 98.7 mmol; toluene 30 ml; [Ru(CO)2(PPh3)X2]2 11.5 mmol; T 150 ◦C.
a
Time required to obtain a complete conversion of alkene.
Selectivity: mol hydroformylation products/mol total products.
b

P. Frediani et al. / Journal of Molecular Catalysis A: Chemical 271 (2007) 80–85
83
selectivity towards alcohol improves while the reaction rate
decreases.
The bromo derivative (2) (entry 5, Table 2) shows the highest
catalytic activity in all experiments while the highest alco-
hol/alkane ratio is obtained using the iodo complex (3) (entry 6,
Table 2).
3.2. Hydrogenation of cyclohexylformaldehyde in the
presence of (1)–(3) as catalysts
The results reported in Table 2 show the ability of the cata-
lysts (1)–(3) to hydroformylate an olefin although the selectivity
towards hydroformylation products is low (among 32.4 and
67.5%) because a large amount of alkene is hydrogenated to
alkane (67.6–32.5%). The direct formation of alcohol together
with low amount of aldehyde suggests that these ruthenium com-
plexes catalyze in a first step the hydroformylation of olefin to
aldehyde. In a second step the aldehyde is hydrogenated to alco-
hol (Scheme 1). These data suggest that these complexes are able
to hydrogenate a carbonylic compound in the presence of hydro-
gen and carbon monoxide. The catalysts (1)–(3) were tested in
the hydrogenation of cyclohexylformaldehyde to confirm this
hypothesis and to evaluate their ability to reduce a carbonylic
compound. The reaction conditions were chosen in order to dis-
criminate among the catalytic activity of the three catalysts: CO
(20 bar) and hydrogen (100 bar) at 120 ◦C with a reaction time
of 20 min (Table 3).
All catalysts hydrogenate cyclohexylformaldehyde but the
best conversion and selectivity were obtained using the catalyst
(1).
3.3. Direct synthesis of cyclohexylmethanol from
cyclohexene through tandem catalysis in the presence of
Co2(CO)8/[Ru(CO)2(PPh3)X2]2 (X = Cl, Br, I).
The complexes [Ru(CO)2(PPh3)X2]2 (X = Cl, Br, I), are
catalytically active in the hydrogenation of cyclohexylformalde-
hyde in the presence of CO, especially the chloro derivative, but
they have a low activity in the hydroformylation of alkene. To
increase the rate of hydroformylation a tandem catalytic sys-
tem was tested. Co2(CO)8 was chosen as a very active and
selective catalyst for the hydroformylation of cyclohexene and
[Ru(CO)2(PPh3)X2]2 (X = Cl, Br, or I) as a catalyst able to
hydrogenate the intermediate aldehyde formed. In this way it
was possible to reduce the hydrogenation of cyclohexene and
to realize the one-pot syntheses of primary alcohols from the
corresponding olefins in high yield (Scheme 2).
The preliminary tests, reported in Table 4, show the pos-
sibility to realize the tandem catalysis obtaining a complete
conversion of cyclohexene and an yield to cyclohexylmethanol
of 78–85%. A few amount of cyclohexylformaldehyde (less than
5%) remained among the reaction products while the hydrogena-
tionofcyclohexenetocyclohexanewasintherange12.0–21.0%.
The best yield in cyclohexylmethanol was reached using the
chloro derivative even if a higher reaction time is required to
obtain a complete conversion of cyclohexene. Trying to opti-
mize the reaction conditions we have also improved the Co/Ru

84
P. Frediani et al. / Journal of Molecular Catalysis A: Chemical 271 (2007) 80–85
Table 6
Hydroformylation of cyclohexene in the presence of [Ru(CO)2(PPh3)Cl2]2) (1) and Co2(CO)8 (4) as catalysts
Run no.
Reaction time (min)
Conversion (%)
Reaction products composition (%)
Selectivitya (%)
Alkane
Alcohol
Aldehyde
23
24
14
20
94
310
85.5
100
100
3.8
4.0
4.0
10.3
27.0
89.0
71.4
69.0
7.0
95.6
96.0
96.0
Influence of the reaction time. Cyclohexene 98.7 mmol; toluene 30 ml; [Ru(CO)2(PPh3)Cl2]2 11.5 mmol; Co/Ru (molar ratio) 3.0; p(H2) 101 bar; p(CO) 42 bar; T
150 ◦C.
a
Selectivity: mol hydroformylation products/mol total products.
and CO/H2 ratios (Table 4). A high pressure of CO increased
the yield of alcohol to 88% together with 7% of aldehyde and
only 4% of alkane.
unchanged (around 95% as hydroformylation products) but the
reaction rate is higher and 235 min are required to obtain the
complete conversion of the alkene.
The gas consumption was very rapid up to 2/3 of the the-
oretical amount, suggesting that the hydroformylation is faster
than hydrogenation. This hypothesis was confirmed by the data
reported in Table 6, where the reaction was quenched at different
reaction time. After 20 min the olefin conversion was 85.5% and
products were the aldehyde (71.4%) and the alcohol (10.3%).
After 94 min the conversion was 100% but the aldehyde was
reduced to 69.0% and the alcohol increased to 27.0%. Finally,
after 310 min, the alcohol was 89.0% and the aldehyde only
7.0%.
3.4. Direct synthesis of primary alcohols from olefins
through tandem catalysis using a
Co2(CO)8/[Ru(CO)2(PPh3)Cl2]2 system
Taking into account that the chloro derivative (1) gave better
results than the other Ru complexes the subsequent tests were
performed using this hydrogenation catalyst (Table 5).
Different olefins were chosen and the results of the one-pot
synthesis of primary alcohols is reported in Table 5. Using pent-
1-ene the yield of hexanols was 87.2% accomplished by a 9.8%
of aldehydes and only 3% of alkene. Using phosphine or arsine
substituted cobalt carbonyls [3f,3g] low yields to alcohols were
obtained.
4. Conclusion
The results reported show that the complexes [Ru(CO)2
(PPh3)X2]2 (X = Cl, Br, I) are catalysts able to transform an
alkene in the alcohol having one more carbon atom through
the hydroformylation of the olefin and its subsequent hydro-
genation to the corresponding alcohol. A large part of the
alkene is however hydrogenated to alkane especially if a CO/H2
ratio was 1:10. In the course of this reaction the starting com-
plexes [Ru(CO)2(PPh3)X2]2 (X = Cl, Br, I) were converted into
mononuclear specie Ru(CO)3(PPh3)X2 (X = Cl, Br, I) that may
be recovered at the end of the reaction.
The hydrogenation activity of the catalysts (1)–(3) reduces
the yield to alcohols because the alkene is partially hydrogenated
to alkane even if carbon monoxide is present in the reaction
medium. This last property is not very usual for hydrogenation
catalysts. With the aim to improve the alcohol we have realized
a tandem system coupling a catalyst able to hydroformylate the
olefin at a high rate [Co2(CO)8] with the ruthenium complexes
active in the hydrogenation of the carbonylic intermediate. By
this way has been possible to realize the one-pot synthesis of
primary alcohols from the corresponding olefins in high yields.
The initial gas consumption was very rapid (up to 2/3 of the
theoretical amount), then decreases. This behaviour and the data
reported in Table 6 confirm the reaction sequences reported in
Scheme 2.
Increasing the molecular weight of the olefin, i.e. using oct-1-
ene, a slightly lower alcohol yield was obtained (82.4%) together
with 14.6% of aldehydes and only 3% of alkane. Lower yield
are reported in the literature [3h]. A branched olefin such as
4-methylpent-1-ene gave a slightly low yield (83%) than pent-
1-ene with a low increase of the resulting alkane (6%).
The straight/branched ratio (S/B) among the alcohols was as
expected for the hydroformylation of the same alkenes [2c].
In all tests reducing the CO/H2 ratio the amount of alcohol
is reduced while the amount of alkane increases (Table 5).
In these reactions the syn gas was in large excess but initially
in a CO/H2 1:3 ratio. Considering that hydrogen was required
for hydroformylation of the olefin and hydrogenation of the
aldehyde, some experiments were carried out using the stoichio-
metric ratio CO/H2 (1:2) (Table 5). The yield remains almost
If we consider that residual aldehydes may be converted into
alcohols when the reaction time is improved, the combination
of the catalysts (1) and (4) in a tandem process gives primary
alcohols from alkenes with very high yields.
Scheme 2.

P. Frediani et al. / Journal of Molecular Catalysis A: Chemical 271 (2007) 80–85
85
Presumably in the course of the reaction the role of the two
catalysts is independent. The starting complexes were modified
at the end of the reaction as happen when the two catalyst are
independently employed. However it must be remembered that
[Co(CO)4]− formed under syngas conditions reacts with the
[Rh(CO)2Cl]2 complex as reported by Joo and Alper [11] Fur-
ther studies are in progress to evidence the specie involved in
this tandem process.
(h) I. Wender, R. Levine, M. Orchin, J. Am. Chem. Soc. 72 (1950)
4375–4378.
[4] (a) M.A. Moreno, M. Haukka, A. Turunen, T.A. Pakkanen, J. Mol. Catal.
A: Chem. 240 (2005) 7–15;
(b) M.A. Moreno, M. Haukka, S. Jaeaeskelaeinen, S. Vuoti, J. Pursiainen,
T.A. Pakkanen, J. Organometal. Chem. 690 (2005) 3803–3814;
(c) K.-I. Tominaga, Y. Sasaki, J. Mol. Catal. A: Chem. 220 (2004) 159–
165;
(d) T. Mitsudo, N. Suzuki, T. Kobayashi, T. Kondo, J. Mol. Catal. A: Chem.
137 (1999) 253–262;
(e) T. Hayashi, Z.H. Gu, T. Sakakura, M. Tanaka, J. Organometal. Chem.
352 (1988) 373–378;
Acknowledgements
(f) A. Fukuoka, H. Matsuzaka, M. Hidai, M. Ichikawa, Chem. Lett. (1987)
941–944;
(g) E.M. Gordon, R. Eisenberg, J. Organometal. Chem. 306 (1986)
C53–C57.
The authors thank the University of Florence, COST
`
D30 action, and the Ministero della Industria, Universita e
Ricerca (MIUR), Programmi di Ricerca Scientifica di Interesse
Nazionale, Cofin. 2004–2005, for financial support and the Ente
Cassa di Risparmio – Firenze for a gift to acquire an NMR
instrument.
[5] (a) K. Tomishige, I. Furikado, T. Yamagishi, S.-I. Ito, K. Kunimori, Catal.
Lett. 103 (2005) 15–21;
(b) A. Solsona, J. Suades, R. Mathieu, J. Organometal. Chem. 669 (2003)
172–181;
(c) L. Ropartz, R.E. Morris, D.F. Foster, D.J. Cole-Hamilton, J. Mol. Catal.
A: Chem. 182–183 (2002) 99–105;
(d) D.L. Packett, J.B. Briggs, D.R. Bryant, A.G. Phillips, D.J. Schreck, A.S.
Guram, K.D. Olson, T.C. Eisenschmid, E.B. Tjaden, WO 9739996 through
Chem. Abstr., 128 (1997) 13065;
(e) A.S. Guram, J.R. Briggs, K.D. Olson, T.C. Eisenschmid, D.L. Pack-
ett, E.B. Tjaden, WO 9739995, through Chem. Abstr., 128 (1997)
3451;
References
[1] K. Griesbaum, A. Bher, D. Biedenkapp, H.W. Voges, D. Garbe, C. Paetz, G.
Collin, D. Mayer, H. Ho¨ke, in: B. Elvers, S. Hawkins, M. Ravenschroft, G.
Schulz (Eds.), Ullmann’s Enciclopedia of Industrial Chemistry, vol. A13,
VCH, Weinheim, 1989, p. 248.
[2] (a) J. Falbe, Carbon Monoxide in Organic Synthesis, Springer Verlag,
Berlin, 1970;
(f) M.C. Cimpson, A.W.S. Currie, J.A.M. Andersen, D.J. Cole-Hamilton,
M.J. Green, Dalton Trans. (1996) 1793–1800;
(g) J.K. MacDougall, D.J. Cole-Hamilton, J. Chem. Soc., Chem. Commun.
(1990) 165–167.
(b) L. Marko, Aspect Homogeneous Catal. (1974) 3–55;
(c) P. Pino, F. Piacenti, M. Bianchi, in: I. Wender, P. Pino (Eds.), Organic
Synthesis via Metal Carbonyls, vol. 2, New York, 1977, p. 44.
[3] (a) C. Crause, L. Bennie, L. Damoense, C.L. Dwyer, C. Grove, N. Grimmer,
W.J. Van Rensburg, M.M. Kirk, K.M. Mokheseng, S. Otto, P.J. Steynberg,
Dalton Trans. (2003) 2036–2042;
[6] D. Konya, K.Q.A. Lenero, E. Drent, Organometallics 25 (2006)
3166–3174.
[7] (a) W.O. Haag, D.D. Whitehurst, in: J.W. Hightower (Ed.), Catalysis, vol.
1, 1973, paper 29, p. 465;
(b) P.-K. Wong, A.A. Moxey, U.S. Pat. 6114588, through Chem. Abstr.,
133 (2000) 207587;
(c) T. Bartik, B. Bartik, B.E. Hanson, J. Mol. Catal. A: Chem. 85 (1993)
121–129;
(d) L. Alvila, T.A. Pakkanen, T.T. Pakkanen, O. Krause, J. Mol. Catal. 71
(1992) 281–290;
(e) W.R. Jackson, P. Perlmutter, G.H. Suh, J. Chem. Soc., Chem. Commun.
(1987) 724–725;
(b) C.U. Pittmann Jr., Q. Ng, A. Hirao, W. Honnick, R. Hanes, Colloq.
Int. du C.N.R.S. n. 281, Relations Entre Catalyse Homogene et Catalyse
Heterogene, C.N.R.S., Paris, 1977, p. 49;
(c) C.U. Pittmann Jr., R.M. Hanes, J. Am. Chem. Soc. 98 (1976) 5402–
5405.
[8] F. Piacenti, M. Bianchi, E. Benedetti, G. Braca, Inorg. Chem. 7 (1968)
1815–1817.
[9] G. Natta, R. Ercoli, Chim. Ind. (Milan) 34 (1952) 503.
[10] B.F.G. Johnson, R.D. Johnston, J. Lewis, J. Chem. Soc. (A) (1969)
792–797.
(f) L.H. Slaugh, R.D. Mullineaux, J. Organometal. Chem. 13 (1968)
469–477;
(g) L.H. Slaugh, R.D. Mullineaux, U.S. Pat. 3,239,570, through Chem.
Abstr., 64 (1966) 19420b;
[11] F. Joo, H. Alper, Can. J. Chem. 63 (1985) 1157–1160.