The reactivity of new (1,5-cyclooctadiene)rhodium acylpyrazolonates towards N- and P-donor ligands: X-ray structures of [Rh(1,5-COD)Qs], [Rh(1,5-COD)(phen)]Qs·0.5H2O (HQs=1-phenyl-3-methyl-4-(2-thenoyl)-pyrazol-5-one) and [Rh(1,5-COD)Br]2

Article abstract of DOI:10.1016/S0022-328X(02)01122-1

Complexes [Rh(1,5-COD)(Q)] have been prepared by the reaction between [Rh(1,5-COD)Cl]₂ (1,5-COD=1,5-cyclooctadiene) and HQ (where HQ=1-phenyl-3-methyl-4-R-pyrazol-5-one: R=2-thenoyl (HQ^s), 2-furanoyl (HQ^o) or tert-butylacetyl (HQ^T). [Rh(1,5-COD)(Q)] react with N₂-donor ligands such as 1,10-phenanthroline (phen) or 2,2-bipyridyl (bipy) yielding ionic compounds [Rh(1,5-COD)(N₂ -donor)]Q. The substitutional lability of 1,5-COD in [Rh(1,5-COD)(Q)] versus mono- and di-organophosphine ligands was also investigated. In all cases 1,5-COD has been displaced. Reaction with two equivalents of PPh₃ gave, upon oxidation of the Rh(I) centre, [Rh(PPh₃)₂(O₂)(Q)] species containing a η²-peroxo-group. Reaction of [Rh(1,5-COD)(Q)] with the chelating P₂-donor 1,2-bis(diphenylphosphino)ethane (dppe) or 4,4′-bis(diphenylphosphino)ferrocene (dppf) yields the peroxo Rh(III) compounds [Rh(dppe)₂O₂]Q^T and [Rh(dppf)O₂(Q^s)] or Rh(I) species [Rh(dppf-O₂)(Q^T)] containing the diphosphine in the oxidised form. Finally the reaction between [Rh(1,5-COD)(Q)] and allylbromide yields the well-known [Rh(1,5-COD)Br]₂. All complexes have been characterised by analytical and spectral data (IR, ¹H and ³¹P{¹H}-NMR spectra). The crystal structures of [Rh(1,5-COD)(Q^s)], [Rh(1,5-COD)(phen)]Q^s and [Rh(1,5-COD)Br₂, all containing a Rh(I) atom in a square coordinate environment, are also reported.

Full text of DOI:10.1016/S0022-328X(02)01122-1

Journal of Organometallic Chemistry 651 (2002) 5–14
www.elsevier.com/locate/jorganchem
The reactivity of new (1,5-cyclooctadiene)rhodium
acylpyrazolonates towards N- and P-donor ligands: X-ray
s
s
structures of [Rh(1,5-COD)Q ], [Rh(1,5-COD)(phen)]Q ·0.5H O
2
s
(
HQ =1-phenyl-3-methyl-4-(2-thenoyl)-pyrazol-5-one) and
[
Rh(1,5-COD)Br]2
a,
a
a
a
Claudio Pettinari *, Fabio Marchetti , Augusto Cingolani , Gianluca Bianchini ,
b,
b
b
Andrei Drozdov *, Vyacheslav Vertlib , Sergei Troyanov
a
Dipartimento di Scienze Chimiche, Uni6ersit a` degli Studi, 6ia S. Agostino 1, 62032 Camerino MC, Italy
b
Chemistry Department, Moscow State Uni6ersity, Vorobje6y Gory, 119899 Moscow, Russia
Received 8 November 2001; accepted 10 December 2001
Abstract
Complexes [Rh(1,5-COD)(Q)] have been prepared by the reaction between [Rh(1,5-COD)Cl] (1,5-COD=1,5-cyclooctadiene)
2
s
o
T
and HQ (where HQ=1-phenyl-3-methyl-4-R-pyrazol-5-one: R=2-thenoyl (HQ ), 2-furanoyl (HQ ) or tert-butylacetyl (HQ ).
Rh(1,5-COD)(Q)] react with N -donor ligands such as 1,10-phenanthroline (phen) or 2,2-bipyridyl (bipy) yielding ionic
[
2
compounds [Rh(1,5-COD)(N -donor)]Q. The substitutional lability of 1,5-COD in [Rh(1,5-COD)(Q)] versus mono- and di-
2
organophosphine ligands was also investigated. In all cases 1,5-COD has been displaced. Reaction with two equivalents of PPh3
2
gave, upon oxidation of the Rh(I) centre, [Rh(PPh ) (O )(Q)] species containing a h -peroxo-group. Reaction of [Rh(1,5-
3
2
2
COD)(Q)] with the chelating P -donor 1,2-bis(diphenylphosphino)ethane (dppe) or 4,4%-bis(diphenylphosphino)ferrocene (dppf)
yields the peroxo Rh(III) compounds [Rh(dppe) O ]Q and [Rh(dppf)O (Q )] or Rh(I) species [Rh(dppf-O )(Q )] containing the
2
T
s
T
2
2
2
2
diphosphine in the oxidised form. Finally the reaction between [Rh(1,5-COD)(Q)] and allylbromide yields the well-known
1
31
1
[
Rh(1,5-COD)Br] . All complexes have been characterised by analytical and spectral data (IR, H and P{ H}-NMR spectra).
2
s
s
The crystal structures of [Rh(1,5-COD)(Q )], [Rh(1,5-COD)(phen)]Q and [Rh(1,5-COD)Br] , all containing a Rh(I) atom in a
2
square coordinate environment, are also reported. © 2002 Elsevier Science B.V. All rights reserved.
Keywords: Rhodium; 4-Acylpyrazolones; b-Diketones; Phosphines; Structures; 31P-NMR; Oxidation
1. Introduction
fluoroacetylacetonate derivatives containing a wide se-
ries of phosphines [4–9]. On the other hand only few
The important role of rhodium and iridium com-
plexes containing b-diketones, olefins and phosphines in
homogeneous catalysis is well established [1–3] since
they were discovered and characterised in the middle of
1960. The main efforts in this field were made on the
investigation of the structure and properties of rhodium
acetylacetonate, trifluoroacteylacetonate and hexa-
*
Corresponding authors. Tel.: +39-0737-402217; fax: +39-0737-
6
37345.
E-mail addresses: pettinar@camserv.unicam.it (C. Pettinari),
drozdov@inorg.chem.msu.ru (A. Drozdov).
Fig. 1. Proligands HQ used in this work.
0
022-328X/02/$ - see front matter © 2002 Elsevier Science B.V. All rights reserved.
PII: S0022-328X(02)01122-1

6
C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
data have been reported in the literature on rhodium
complexes containing 1-phenyl-3-methyl-4-R(CꢀO)-
pyrazol-5-ones HQ (R=Me or Ph) (Fig. 1) — a fam-
ily of heterocyclic proligands analogues of b-diketones
2.1. Synthesis of the ligands
s
2.1.1. HQ
To a hot dioxane solution of 3-methyl-1-phenylpyra-
zole-5-one (15 g, 0.088 mol) Ca(OH) (12 g, 0.162 mol)
[
10,11]. In order to understand the influence of the
-R(CꢀO) fragment on the geometry and stability of
2
4
was added and the resulting mixture refluxed for 30
min. Then 2-thiophenecarbonyl chloride (12.61 g, 0.086
mol) was added dropwise to the suspension and the
reaction mixture refluxed for 24 h. The yellow precipi-
tate formed was treated with 350 ml of 2 N HCl and
then filtered off and re-crystallised from MeOH (78%
yield), m.p. 152–155 °C. Anal. Calc. for C H N O S:
rhodium complexes containing pyrazolonate ligands we
describe here the synthesis and characterisation of
rhodium derivatives with different 4-acylpyrazolones
containing substituents with additional donor atoms
(
such as 2-thienyl, 2-furanyl groups) or sterically hin-
dered ones (neo-pentyl group), namely 1-phenyl-3-
1
5
12
2
2
o
methyl-4-(2-furoyl)-pyrazole-5-one (HQ ), 1-phenyl-
C, 63.36; H, 4.25; N, 9.85; S, 11.28. Found: C, 63.39;
H, 4.35; N, 9.86; S, 11.21%. IR (Nujol, cm ): 2700br
s
−1
3
-methyl-4-(2-thenoyl)-pyrazole-5-one (HQ ), and 1-
phenyl-3-methyl-(4-tert-butylacetyl)-pyrazole-5-one
w(O···H), 1634s, 1596s, 1558m w(CꢀO, CꢀC); 429s, 383
T
1
(
HQ ) (Fig. 1). The reactivity of [Rh(1,5-COD)Q]
s; 369s; 315m, 295s, 277 s. H-NMR (CDCl , 300
3
s
derivatives toward N-donor such as 1,10-phenanthro-
MHz): l 2.43 (s, 3H, 3-CH3 ), 7.17 (d, 1H, C H S),
Q
4
3
line (phen) and 2,2%-bipyridyl (bipy) or P-donors such
7.29 (t, 1H, C H S), 7.47 (t, 2H, C H ), 7.72 (t, 1H,
4 3 6 5
as triphenylphosphine (PPh ), 1,2-bis(diphenylphos-
C H ), 7.74 (d, 1H, C H S), 7.84 (d, 2H, C H ), 12.1
3
6
5
4
3
6
5
phino)ethane
(dppe)
and
4,4-bis(diphenylphos-
(br, 1H, OH).
phino)ferrocene (dppf) has also been investigated. The
results of the reaction of [Rh(1,5-COD)Q] with allyl
o
2.1.2. HQ
o
bromide are also reported. The crystal structures of
The compound HQ (yellow) has been obtained as
described for HQ using 2-furoyl chloride. M.p. 103–
105 °C. Anal. Calc. for C H N O : C, 67.16; H, 4.51;
s
S
[
Rh(1,5-COD)(m-Br)] , [Rh(1,5-COD)Q ] and [Rh(1,5-
2
s
COD)(Phen)]Q ·0.5H O were determined. The latter
2
15 12
2
3
one is the first example of anionic acylpyrazolonate in
rhodium complexes.
N, 10.44. Found: C, 67.19; H, 4.57; N, 10.40%. IR
−
1
(Nujol, cm ): 2700br w(O···H), 1625m, 1585 s; 1531 s
w(CꢀO, CꢀC), 690s; 604s; 585s, 509s; 391m; 355s; 282s.
1
o
3Q
H-NMR (CDCl , 300 MHz): l 2.59 (s, 3H, 3-CH ),
3
6
.62 (t, 1H, C H O), 7.25 (t, 1H, C H O), 7.42 (m, 3H,
4 3 4 3
C H ), 7.69 (d, 1H, C H O), 7.85 (d, 2H, C H ).
6
5
4
3
6
5
2. Experimental
T
2.1.3. HQ
T
Solvents were used as supplied or distilled using
The ligand HQ has been prepared according to the
standard methods. The samples for microanalyses were
dried in vacuum to constant weight (293 K, ca. 0.1
Torr). Elemental analyses (C, H, N) were performed
in-house with Fisons Instruments 1108 CHNS-O Ele-
mental Analyser. IR spectra were recorded from 4000
method outlined in the literature [13].
2.2. Synthesis of complexes
s
2.2.1. [Rh(COD)(Q )] (1)
To an EtOH solution of HQ (0.49 g, 1.0 mmol),
−
1
s
to 100 cm
using a Perkin–Elmer System 2000 FT-IT
1
instrument. H spectra were recorded in a VXR-300
Varian spectrometer operating at 300 MHz or in a
[Rh(COD)(m-Cl)] (0.54 g, 2.0 mmol) and NEt (0.28
2
3
ml, 2 mmol) were added. The reaction mixture was
stirred for 1 h under reflux, and then cooled to room
temperature (r.t.); a yellow precipitate formed was
31
V-200 Varian operating at 200 MHz. P-NMR spectra
were recorded in a VXR-300 Varian spectrometer oper-
ating at 121.4 MHz. Proton chemical shifts are reported
filtered off, washed with Et O and dried in vacuo to
2
in ppm versus Me Si while phosphorus chemical shifts
constant weight to give 1.20 g of 1 (62.5% yield). M.p.
146 °C. Anal. Calc. for C H N O RhS: C, 55.88; H,
4
are in ppm versus 85% H PO . Melting points (m.p.)
3
4
23 23
2
2
were taken in a SMP3 Stuart scientific instrument and
in a capillary apparatus.
Triphenylphosphine (PPh3), 1,2-bis(diphenylphos-
5.67; N, 5.67; S, 6.48. Found: C, 55.67; H, 5.75; N,
−
1
5.70; S, 6.54%. IR (Nujol, cm ): 1602s, 1588s, 1557s,
1537s, 1530s w(CꢀO, CꢀC), 1470sh w(CꢀC, COD), 775s,
685s (z(CꢁH), w(COD)), 572m, 510m, 478m
phino)ethane
phino)ferrocene (dppf), 1,10-phenanthroline (phen),
,2%-bipyridyl (bipy) and allylbromide were purchased
from Aldrich (Milwaukee) and used as received.
(dppe),
1,1%-bis(diphenyl-phos-
w(RhꢁCꢁH), 410m, 390m w(RhꢁO), 384m, 365m
1
2
w(RhꢁC). H-NMR (CDCl , 200 MHz): l 1.74–1.86
3
s
3Q
(m, 4H, CH2COD), 2.07 (s, 3H, 3-CH ), 2.48–2.53 (m,
[
(
Rh(COD)Cl]2 was synthesised from RhCl ·3H O
Aldrich) and purified using a standard procedure [12].
4H, CH2COD), 4.18 (s, 2H, CHCOD), 4.28 (s, 2H,
CHCOD), 7.08 (m, 1H, C H S), 7.18 (t, 1H, C H ),
3
2
4
3
6
5

C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
7
7
7
.32–7.40 (m, 3H, C H +C H S), 7.56 (d, 1H, C H S),
C H N O Rh: C, 63.83; H, 4.74; N, 8.51. Found: C,
35 31 4 3
63.73; H, 4.68; N, 8.47%. IR (Nujol, cm ): 1613s,
6
5
4
3
4
3
−
1
.87 (d, 2H, C H ).
6
5
1
588s, 1543sh w(CꢀO, CꢀC), 1460sh w(CꢀC, COD),
o
2
.2.2. [Rh(COD)(Q )] (2)
775s, 718s (z(CꢁH), w(COD)), 600m, 510m, 491sh,
1
Compound 2 (yellow) has been prepared as described
for 1 (80% yield). M.p. 171 °C. Anal. Calc. for
C H N O Rh: C, 57.75; H, 4.85; N, 5.86. Found: C,
480sh w(RhꢁCꢁH), 364m w(RhꢁC), 306w w(RhꢁN). H-
NMR (CD OD, 300 MHz): l 2.20–2.23 (m, 4H,
3
o
3Q
CH2COD), 2.33 (s, 3H, 3-CH ), 2.63–2.67 (m, 4H,
CH2COD), 4.83 (s, 4H, CHCOD), 6.51 (m, 1H, C H O),
7.07 (t, 1H, C H O), 7.19 (t, 2H, C H ), 7.62 (t, 1H,
C H ), 7.71 (d, 2H, CH ), 7.86 (d, 1H, C H S), 7.93
(t, 2H, CHphen), 8.12 (d, 2H, CHphen), 8.36 (d, 2H,
C H ), 8.75 (d, 2H CHphen).
2
3
23
2
3
−
1
5
1
6
7.65; H, 5.00; N, 5.62%. IR (Nujol, cm ): 1596s,
563s, 1520s w(CꢀO, CꢀC), 1470sh w(CꢀC, COD), 778s,
88s (z(CꢁH), w(COD)), 572w, 515m, 490m, 475m
4
3
4
3
6
5
6
5
phen
4
3
w(RhꢁCꢁH), 415w, 398sh w(RhꢁO), 386m, 379m
1
w(RhꢁC). H-NMR (CDCl , 200 MHz): l 1.74–1.87
3
6
5
o
3Q
(
m, CH2COD), 2.21 (s, 3H, 3-CH ), 2.50–2.60 (m, 4H,
s.
CH2COD), 4.18 (s, 2H, CHCOD), 4.29 (s, 2H, CHCOD),
.55 (m, 1H, C H O), 6.98 (d, 1H, C H O), 7.18 (t, 1H,
C H ), 7.36 (t, 2H, C H ), 7.59 (d, H, C H O), 7.87 (d,
2.2.6. [Rh(COD)(bipy)]Q 2H O (6)
2
6
Compound 6 (red–orange) has been prepared as
described for 4 by using bipy instead of phen (80%
yield). M.p. (dec.) 80 °C. Anal. Calc. for
C H N O RhS: C, 57.73; H, 5.14; N, 8.16; S, 4.67.
4
3
4
3
6
5
6
5
4
3
2H, C H ).
6 5
33
35
4
4
T
2
.2.3. [Rh(COD)(Q )] (3)
Compound 3 (pale-yellow) has been prepared as
Found: C, 57.62; H, 4.87; N, 8.02; S, 4.58%. IR (Nujol,
−
1
cm ): 3400br w(OꢁH), 1614s, 1602s, 1588s, 1539s,
1504s w(CꢀO, CꢀC), 1454s w(CꢀC, COD), 768s, 725m
(z(CꢁH), w(COD)), 600m, 513m, 484m w(RhꢁCꢁH),
described for 1 (91% yield). M.p. 175 °C. Anal. Calc.
for C H N O Rh: C, 59.75; H, 6.48; N, 5.81. Found:
2
4
31
2
2
−
1
C, 60.00; H, 6.61; N, 5.75%. IR (Nujol, cm ): 1614sh,
599s, 1570br, 1537s, 1500s w(CꢀO, CꢀC), 1475sh
418sbr, 398s br, 380sh, 360m w(RhꢁC), 302w w(RhꢁN).
1
1
H-NMR (CDCl , 200 MHz, 295 K): l 1.90–2.05 (m,
3
s
3Q
w(CꢀC, COD), 775w, 690s (z(CꢁH), w(COD)), 612m,
4H, CH2COD), 2.38 (s, 3H, 3-CH ), 2.50–2.60 (m, 4H,
CH2COD), 4.35 (br, 4H, CHCOD), 7.00 (m, 2H, C H S),
7.20–7.30 (m, 2H, C H +C H S), 7.50–7.60 (m, 2H,
C H +C H S), 7.60 (d, 2H, CHbipy), 7.90–8.10 (m,
6 5 4 3
4H, CH ), 8.40 (m, 2H, C H ), 8.70–8.80 (m, 2H,
CHbipy). H-NMR (CDCl , 200 MHz, 223 K): l 2.10
(m, 4H, CH2COD), 2.44 (s, 3H, 3-CH ), 2.54 (m, 4H,
5
3
9
3
10m, 485s w(RhꢁCꢁH), 410w, 395m w(RhꢁO), 385m,
4
3
1
56m w(RhꢁC). H-NMR (CDCl , 300 MHz): 1.03 (s,
3
6 5 4 3
T
H, CH Q), 1.82–1.89 (m, 4H, CH2COD), 2.25 (s, 3H,
3
T
3
-CH Q), 2.46–2.52 (m, 4H, CH2COD), 2.62 (s, 2H,
CH2Q), 4.18 (s, 2H, CHCOD), 4.23 (s, 2H, CHCOD), 7.19
t, 1H, C H ), 7.31 (t, 2H, C H ), 7.83 (d, 2H, C H ).
bipy 6 5
1
T
3
s
3Q
(
6
5
6
5
6
5
CH2COD), 4.40 (br, 4H, CHCOD), 7.01 (m, 2H, C H S),
4
3
s.
2
.2.4. [Rh(COD)(phen)]Q 0.5H O (4)
7.30 (m, 2H, C H +C H S), 7.50 (d, 2H, CHbipy), 7.53
2
6 5 4 3
To a MeOH (20 ml) suspension of 1 (0.32 g, 0.64
(m, 4H, C H +C H S), 8.07 (m, 4H, CHbipy), 8.96 (m,
6
5
4
3
mmol) phen (0.115 g, 0.64 mmol) was added. The
2H, CHbipy).
orange solution formed was stirred overnight. After the
o.
addition of Et O (20 ml) a red precipitate formed which
2.2.7. [Rh(COD)(bipy)]Q 2H O (7)
2
2
was re-crystallised from MeOH–Et O 1/1. About 0.380
g of pure 4 was obtained (88% yield). M.p. 170–
Compound 7 (red–orange) has been prepared as
described for 4 by using bipy (85% yield). M.p. (dec.)
170 °C. Anal. Calc. for C H N O Rh: C, 59.11; H,
2
1
4
8
72 °C. Anal. Calc. for C H N O RhS: C, 61.49; H,
35 32 4 2.5
33 35
4
5
.72; N, 8.20; S, 4.69. Found: C, 61.43; H, 4.67; N,
5.26; N, 8.36. Found: C, 59.12; H, 5.07; N, 8.22%. IR
−
1
−1
.27; S, 4.71%. IR (Nujol, cm ): 1614s, 1588s, 1552s
(Nujol, cm ): 3400br w(OꢁH), 1610sh, 1602s, 1567s,
w(CꢀO, CꢀC), 1475sh w(CꢀC, COD), 770s, 698m
1524S w(CꢀO, CꢀC), 1470sh w(CꢀC, COD), 768m,
726m (z(CꢁH), w(COD)), 600m, 511m, 484w
(
3
z(CꢁH), w(COD)), 599m, 516m, 492m w(RhꢁCꢁH),
1
61m, 344m w(RhꢁC), 301w w(RhꢁN). H-NMR
w(RhꢁCH), 448w, 418w, 398v w, 360w w(RhꢁC), 304w
1
(CDCl , 200 MHz): l 1.95–2.11 (m, 4H, CH2COD), 2.30
w(RhꢁN). H-NMR (CDCl , 200 MHz, 293 K): l 2.05
3
3
s
s
3Q
(
s, 3H, 3-CH Q), 2.55–2.70 (m, 4H, CH2COD), 4.56 (s,
(m, 4H, CH2COD), 2.48 (s, 3H, 3-CH ), 2.20–2.40 (m,
3
4
H, CHCOD), 6.87–7.00 (m, 2H, C H S), 7.05 (t, 1H,
4H, CH2COD), 4.40 (br, 4H, CHCOD), 6.50 (br, 1H,
C H O), 7.0–8.0 (m br, 7H, C H +C H O), 7.83 (d,
4
3
C H S), 7.18 (t, 1H, C H ), 7.36 (d, 1H, C H S), 7.57
4
3
6
5
4
3
4
3
6
5
4
3
(
d, 2H, CHphen), 7.60 (m, 1H, C H ), 7.86 (t, 2H,
2H, CHbipy), 8.07 (m, 2H, CHbipy), 8.36 (d, 2H, CHbipy),
8.72 (m, 2H, CHbipy).
6
5
CHphen), 7.95 (d, 2H, CHphen), 8.32 (d, 2H, C H ), 8.79
6
5
(
d, 2H CHphen).
s
2
.2.8. Synthesis of [Rh(PPh ) (O )(Q )] (8)
3
2
2
o
2
.2.5. [Rh(COD)(phen)]Q (5)
Compound 5 (yellow) has been prepared as described
for 4 (90% yield). M.p. 282 °C. Anal. Calc. for
To a Et O suspension (30 ml) of 1 (0.5 g, 1 mmol)
PPh (053 g, 2 mmol) dissolved in the same solvent (30
ml) was added. A dark-red solution formed was stirred
2
3

8
C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
S
vigorously for 1 h. A brownish precipitate (0.78 g)
3H, 3-CH3Q), 4.19 (br, 4H, CHdppf), 4.33 (br, 4H,
3
1
formed was filtered off and washed with Et O (83%
CHdppf), 6.80–8.0 (m br, 28H, C H +C H S). P-
2
6 5 4 3
yield). M.p. (dec.) 136 °C. Anal. Calc. for
NMR (CDCl , 121 MHz, 295 K): l 44.11 (d, JRhꢁP=
3
C H N O P RhS: C, 64.97; H, 4.38; N, 2.97; S, 3.40.
145.8 Hz), 43.1 (d, JRhꢁP=129.1 Hz)
5
1
41
2
4 2
Found: C, 64.68; H, 4.59; N, 2.87; S. 3.35%. IR (Nujol,
cm ): 1600s, 1588s, 1562s, 1530s w(CꢁO, CꢁC),
−
1
T
2.2.12. [Rh(dppe) (O )](Q ) (12)
2
2
1
5
3
1
7
2
462sh, 1450s w(PꢁPh), 858s br w(OꢁO), 540s, 524s,
Compound 12 (brownish) has been obtained as de-
scribed for 11 in THF (40% yield). M.p. (dec.) 195 °C.
Anal. Calc. for C H N O P Rh: C, 67.89; H, 5.61; N,
14s, 493s w(CꢁPꢁC), 457m, 444m, 429m w(RhꢁO),
1
66m, 322w. H-NMR (CDCl , 200 MHz, 295 K): l
3
68 67
2
4 4
.76 (s, 3H, Me), 6.85–7.60 (m, 36H, C H +C H S),
2.33. Found: C, 67.60; H. 5.80; N, 2.20%. IR (Nujol,
cm ): 1618s, 1590s, 1580s, 1574sh, 1568s, 1558s,
6
5
4
3
3
1
−1
.80 (d, 2H, C H S). P-NMR (CDCl , 121.4 MHz,
4
3
3
95 K): l 15.8d (JRhꢁP=89.6 Hz).
1532s, 1520s w(CꢁO, CꢁC), 1450br w(PꢁPh), 879br
w(OꢁO), 536s, 505s, 482s w(CꢁPꢁC), 469m, 441m, 423m
o
2
.2.9. Synthesis of [Rh(PPh ) (O )(Q )] (9)
w(RhꢁO), 397w, 386w, 358w,m, 350m, 325w, 301w.
3
2
2
1
Compound 9 (brownish) has been prepared as de-
scribed for 8 in toluene (76% yield) by using compound
as the starting reagent. M.p. (dec.) 120 °C. Anal.
Calc. for C H N O P Rh: C, 66.10; H, 4.46; N, 3.02.
H-NMR (CDCl , 200 MHz, 295 K): l 1.10 (s, 9H,
3
T
9Q
T
3Q
C H ), 2.11 (br, 8H, CH
), 2.46 (s, 3H, 3-CH ),
4
2dppe
T
31
2
2.53 (s, 2H, CH2 ), 6.8–7.8 (m, 45H, C H ). P-NMR
Q 6 5
(CDCl , 121.4 MHz): l 51.06 (double triplet, JRhꢁP=
126 Hz, JPꢁP=17 Hz), 44.97 (double triplet, JRhꢁP=91
Hz, JPꢁP=17 Hz).
5
1
41
2
5
2
3
−
1
Found: C, 66.08; H, 4.63; N, 2.97%. IR (Nujol, cm ):
1
603m, 1579s, 1551s, 1527sh w(CꢁO, CꢁC), 1461s
w(PꢁPh), 883br w(OꢁO), 541s, 520s, 511s, 496sh
1
T
w(CꢁPꢁC), 456m, 440w, 420w w(RhꢁO). H-NMR
2.2.13. [Rh(dppf-O )(Q )] (13)
2
o
3Q
(CDCl , 300 MHz): l 1.65 (s, 3H, 3-CH ), 6.50 (d,
Compound 13 (brownish) has been obtained from
the reaction of 1 mmol of 3 with 2 mmol of dppf in
THF. The reaction mixture was stirred for 24 h. A
precipitated formed when Et O was added to the solu-
tion was re-crystallised from THF–Et O 1/1 (30%
yield). M.p. (dec.) 225 °C. Anal. Calc. for
C H FeN O P Rh: C, 62.52; H, 4.93; N, 2.92. Found:
C, 62.80; H. 4.80; N, 2.80%. IR (Nujol, cm ): 1599s,
3
1
H, C H O), 6.50 (d, 1H, C H O), 7.0–8.0 (m br, 31H,
4 3 4 3
3
1
C H +C H O). P-NMR (CDCl , 121.4 MHz): l
6
5
4
3
3
1
1
1
1
5.86 (d, JRhꢁP=88 Hz). H-NMR (C D , 300 MHz): l
.93 (s, 3H, 3-CH3 ), 5.90 (br, 1H, C H O), 6.60 (d,
6
6
2
o
Q
4
3
2
H, C H O), 6.80–8.2 (m br, 36H, C H +C H O).
4
3
6
5
4
3
3
1
P-NMR (C D , 121.4 MHz): l 17.16 (d, JRhꢁP=90
6
6
50 47
2
4 2
−
1
Hz).
1
587s, 1574s, 1530m w(CꢁO, CꢁC), 1470sh w(PꢁPh),
T
2
.2.10. Synthesis of [Rh(PPh ) (O )(Q )] (10)
1090 w(PꢁO), 566s, 523s, 513s, 496s w(CꢁPꢁC), 472m,
3
2
2
1
Compound 10 (brownish) has been prepared as de-
scribed for 8 (79% yield). M.p. (dec.) 170 °C. Anal.
Calc. for C H N O P Rh: C, 67.10; H, 5.31; N, 3.01.
Found: C, 66.90; H. 5.51; N, 2.96%. IR (Nujol, cm ):
462m, 437m w(RhꢁO), 397w, 351m, 325w. H-NMR
T
9Q
(CDCl , 200 MHz, 295 K) l 0.91 (s, 9H, C H ), 2.13
3
4
T
3Q 2Q
T
(s, 3H, 3-CH ), 2.16 (s, 2H, CH ), 4.16, 4.22, 4.27,
4.28 (4s, 8H, CHdppf), 7.0–8.2 (m, 25H, C H ). P-
6 5
5
2
49
2
4
2
−
1
31
1
603s, 1590s, 1577s, 1568s, 1532s w(CꢁO, CꢁC), 1442s
NMR (CDCl , 121.4 MHz): l 28.53br.
3
w(PꢁPh), 889m w(OꢁO), 544s, 524s, 511s, 490m
w(CꢁPꢁC), 468m, 453m, 435m w(RhꢁO), 418m, 398w,
2.2.14. [Rh(COD)(v-Br)] (14)
2
1
3
57m, 325w. H-NMR (C D , 300 MHz, 295 K): l 1.19
Compound 14 has been obtained when 1 mmol of
either compound 1 or 3 reacts with 2 mmol of allylbro-
mide in benzene. Yellow-brownish crystals formed
when the concentrated benzene solution was stored for
6
6
T
4 9Q 2Q
T
(
s, 9H, C H ), 1.54 (s, 2H, CH ), 2.14 (s, 3H, 3-
T
31
CH3 ), 6.70–7.10, 7.6–7.8 (m, 35H, C H ). P-NMR
Q
6
5
(
C D , 121.4 MHz): l 16.7 (d, JRhꢁP=109.2 Hz).
6 6
2
4 h at 277 K. Physical and analytical data correspond
s
2
.2.11. [Rh(dppf )(O )(Q )] (11)
to those reported in Ref. [14].
2
To a Et O suspension of compound 1 (0.32 g, 0.64
2
mmol), dppf (0.35 g, 0.64 mmol) was added. After 2 h
a clear orange solution formed was concentrated under
vacuum. A yellow-brownish precipitate was filtered off
washed with diethyl ether and recrystallised from
MeOH (89% yield). M.p. (dec.) 190 °C. Anal. Calc. for
C H FeN O P RhS: C, 60.51; H, 4.04; N, 2.88; S,
2.3. Crystallographic study
The data for complexes 1, 4 and 14 were collected in
an Image-Plate diffractometer (IPDS, Stoe) using
graphite monochromated Mo–Ka radiation (u=
0.71073 A). Numerical absorption correction was ap-
,
4
9
39
2
4 2
3
.30. Found: C, 60.54, H, 4.38; N, 2.82; S, 2.93%. IR
plied only for the bromine-containing complex 14. The
structures were solved by direct methods (SHELXS 86
[15a]) and refined anisotropically for all non-hydrogen
atoms using SHELXL 93 [15b]. Hydrogen atoms (except
−
1
(
Nujol, cm ): 1590s, 1568s, 1531s, 1509s w(CꢁO,
CꢁC), 1445sh w(PꢁPh), 550s, 516m, 493s, 462m, 434m
1
w(CꢁPꢁC), 347w, 302w. H-NMR (CDCl ): l 2.54 (s,
3

C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
9
Table 1
Crystal data and structure refinement parameters for Rh(COD) derivatives
Rh(1,5-COD)(Qs)]
Rh(1,5-COD)(phen)Q ·0.5H O
s
[Rh(1,5-COD)(m-Br)]2
[
2
Empirical formula
Formula weight
Crystal system
C23H23N O RhS
494.40
Monoclinic
C35H32N O2.5RhS
683.82
Orthorhombic
Pbca
C16H24Br Rh
2
581.99
Monoclinic
I2/m
2
2
4
2
Space group
P2 /c
1
Unit cell dimensions
a (A
,
)
)
)
7.796(2)
13.190(3)
20.125(4)
97.75(3)
2050.8(8)
4
0.957
0.5×0.5×0.2
180
20.153(3)
22.240(4)
26.337(5)
90
11 804(4)
16
0.691
0.3×0.3×0.2
180
11.830(3)
11.555(3)
12.443(3)
97.78(3)
1692.3(7)
4
6.661
0.5×0.3×0.2
180
b (A
,
c (A
i (°)
,
3
V (A
,
)
Z
Absorption coefficient (mm−1)
Crystal size (mm)
Temperature/K
q Range for data collection (°)
Reflections collected
Independent reflections
Data/parameters
2.5–27.0
9880
4347 [Rint=0.059]
3307/275
0.0691
2.5–25.8
57 805
11 204 [Rint=0.145]
7656/786
0.1290
3.5–27.8
4971
2055 [Rint=0.081]
1647/94
0.1045
2
wR2 (on F )
R1 [I]2|(I)]
Largest difference peak and hole (e A
0.0385
0.698 and −0.764
0.0565
0.965 and −0.668
0.0413
1.364 and −1.440
−3)
,
those of the water molecule in the structure of 4) were
included in the calculated positions and refined in the
riding mode.
Crystallographic data and some details of data col-
lection and structures refinement are reported in Table
enes and olefins [8,10,11,18]. The presence of w(RhꢁC)
and w(RhꢁO) stretching vibrations at ca. 390–360 and
−
1
420–390 cm , typical of RhꢁCOD and Rh(I)–b-dike-
tonates complexes, respectively, confirms the formation
1
of the products. In the H-NMR spectra of 1–3 there
1. The interatomic distances for Rh environment are
are sets of signals due to the COD and acylpyra-
zolonate moieties. All the olefin resonances are shifted
downfield with respect to the free ligand that confirms
the coordination [19].
listed in Table 2.
3. Results and discussion
T
o
s
Table 2
The ligands HQ , HQ and HQ were prepared by a
Coordination of the Rh atom (distances in A) in the crystal structures
,
of 1, 4, and 14
standard procedure reported by Pettinari et al. [13] and
Jensen [16]. HQ has already been reported by Pettinari
et al. [13] in an investigation on barium(II) complexes,
while HQ and HQ according to our knowledge were
prepared by us with the aim to investigate the influence
of 2-thienyl and 2-furanyl substituents on the structure
and reactivity of rhodium complexes. While this work
has been in progress the ligand HQ has been reported
and structurally characterised [17].
T
Distance
1 (X=O) 4 (X=N) Rh(1) Rh(2)
14 (X=Br)
o
s
RhꢁC(1)
RhꢁC(2)
RhꢁC(5)
RhꢁC(6)
RhꢁX(5)
RhꢁX(6)
2.100(3)
2.139(8)
2.124(8)
2.144(7)
2.129(8)
2.085(5)
2.109(7)
2.125(6)
2.146(7)
2.145(7)
2.154(8)
2.090(5)
2.089(6)
2.119(6)
2.117(6)
2.110(5)
2.117(6)
2.538(1)
2.535(1)
2.110(2)
2.103(3)
2.127(2)
2.067(2)
2.077(2)
s
T
The interaction between [Rh(COD)Cl] and HQ ,
HQ or HQ in the presence of NEt results in the
2
o
s
3
formation of [Rh(COD)Q] complexes 1–3 (Scheme 1)
which are yellow solids soluble in methanol, acetone
and chlorinated solvents and slightly soluble in non-po-
lar solvents. They are sufficiently stable in air and can
be synthesised without using the Schlenk technique. In
the IR spectra of 1–3 the w(C···O, C···C) bands at
−
1
1500–1600 cm
clearly indicate the bidentate-chelat-
ing mode of the acylpyrazolonate as already found in
the analogous b-diketonate derivatives containing di-
Scheme 1.

1
0
C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
scribed in the case of rhodium complexes with
b-diketones such as acetylacetone or hexafluoroacety-
lacetone. Signals multiplicity and patterns of chemical
1
shifts in H-NMR spectra of 4–7 are also in accordance
with these formulations. A similar substitution for
[Rh(COD)L] derivatives has been recently reported by
N-donor ligands such as aliphatic diamines, imidazoles,
pyridines and related compounds [22]. The reaction of
[
Rh(1,5-COD)X] (X=Cl, Br) with NꢁN ligand was
2
also shown to give the ionic compounds
Rh(COD)(NꢁN)][Rh(COD)X ] [23], but in our case no
[
2
analogous complexes have been obtained, may be due
to the sterical hindrances in hypothetical
Rh(COD)(Q) ] anion. Recently it has been reported
a
−
[
2
that b-diketonate ligands (e.g. acetylacetonate) can be
easily substituted by other N-donors, such as tris(pyra-
zolyl)borates [24], some O-donors (N-acetyl-3-bu-
Fig. 2. Molecular structure of derivative 1.
tanoyl-1,5-dihydro-4-hydroxy-2H-pyrrol-2-one
and mixed O,P-donors (polyether bridged diphosphines
26]) that confirms the dependence of the substitution
[25])
[
on the nucleophility of the entering group.
The phen-containing complexes 4 and 5 are much
more stable with respect to bipy derivatives and can be
isolated with almost quantitative yield even if the syn-
thesis was performed in air. The bipy derivatives 6 and
7
can be obtained in good yields only when the reac-
tions were carried out in nitrogen atmosphere. Com-
plexes 6 and 7 are air sensitive to oxidation and
hydration. Complexes 6 and 7 always crystallise with
two molecules of water that can be explained by the
more flexible nature of bipy with respect to phen and
Scheme 2.
The structure of 1 was confirmed by X-ray single
crystal crystallography (Fig. 2). The Rh(I) atom adopts
an usual square-planar coordination with the carbonyl
oxygens and the centres of the double bonds on the
sides of the square. The average RhꢁC distance, 2.110
by the possibility of H-bonding between H O and
2
heteroatoms of acylpyrazolonate anion. Such difference
has been already mentioned in 1-phenyl-3-methylpyra-
zole-5-one derivatives [11]. The crystal structure of 4,
A
,
, corresponds well to the values for Rh(COD)(b-dike-
tonate) complexes known from the literature: 2.102 A
in a previous acetylacetonate complex [20] or 2.115 A in
the trifluoroacetylacetonate complex [8]. The average
RhꢁO distance, 2.072 A, is also well comparable with
the similar distances, 2.060 and 2.062 A, found in the
two complexes mentioned above.
s
[
Rh(COD)(phen)](Q )·0.5 H O, has been determined
2
,
that confirms the ionic nature of the compound (Fig.
). The square coordination of the two independent Rh
atoms is characterised by the average RhꢁC distance of
.146 A . These values
,
3
,
2
and RhꢁN distance of 2.103 A
, ,
,
are close to the corresponding distances found for the
related structure of [Rh(COD)(bipy)](PF ): 2.135 and
6
The reactivity of 1–3 toward N- and P-donor ligands
has also been investigated. The reaction of 1 or 2 with
phen or bipy results in the formation of the ionic
complexes 4–7 by the displacement of the acylpyra-
zolonate ligand from the Rh(I) coordination sphere by
2
.095 A [27]. The RhꢁC distances in both these cationic
,
complexes are somewhat longer than those in the neu-
tral [Rh(COD)(b-diketonate)] derivatives. It should be
noticed that both Q anions in 4 have a different
s
s
configuration from that found in 1 where Q acts as a
the N -donor ligand as shown in Scheme 2.
2
chelating ligand. Due to the rotation around the CꢁC
bond the trans-orientation of the carbonyl groups is
close to that in the free ligand [17]. It can be concluded
on the basis of the distances from the O(5)w to both
anionic ligands: O5···O4, 2.837 A
A, that the water molecule connects them to the dimer
,
by means of weak H-bonds (Fig. 4).
In the IR spectra of 4–7 the w(C···O, C···C) bands
are typical of complexes containing anionic not coordi-
nated b-diketonate species [11]. The presence of RhꢁN
−
1
−1
(
ca. 300 cm ) and RhꢁC (ca. 360 cm ) stretching
,
and O5···N6%, 3.098
vibrations is in accordance with the formation of
Rh(COD)(NꢁN)] species which were already known
as perchlorate, chloride, tetraphenylborate or hex-
+
The reaction of [Rh(COD)Q] complexes 1–3 with
triphenylphosphine results in the substitution of the
afluorophosphate salts [21], but have never been de-

C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
11
31
31
1
40.9 Hz, respectively; P– P coupling constants of
2
8.6 and 28.8 Hz, respectively) were immediately de-
31
1
tected in the P{ H}-NMR of a benzene solution con-
taining 0.1 mmol of 1 and 0.2 mmol of PPh . After 5
3
min these signals disappear and the same signals found
in the spectra of 8–10 appear (see below). The w(C···O)
and w(C···C) vibrations in the IR spectra of 8–10 fall in
region typical for the coordinated acylpyrazolone
[
10,11]. The PꢁC bands are similar to those reported for
other triphenylphosphine derivatives, e.g. Rh(PPh ) Cl
3
3
[
29] and different from those found in triphenylphos-
1
phine–oxide complexes [28a,30]. The H-NMR spectra
of 8–10 exhibit all resonances due to the acylpyra-
zolonate moiety and PPh . The methyl resonance is
3
upfield shifted with respect to that found in 1–3. The
31
P-NMR spectra of 8–10 exhibit a doublet at ca. 16.0
ppm with JRhꢁP typical of Rh(III) complexes containing
PPh3 and b-diketones (23.0 d (JRhꢁP=90.9 Hz) in
RhCl (PPh ) (acac) and 24.7 d (JRhꢁP=99.6 Hz) in
Fig. 3. Molecular structure of cation in derivative 4.
2
3 2
RhCl(OOH)(PPh ) (acac) [28b]). The large difference in
3
2
the JRhꢁP coupling constant values of complexes 8 and
with respect to 10 can be due to both large difference
9
in steric and electronic properties of the pyrazolonato
ligand and different isomeric cis- or trans-P Rh
2
configuration. While heating or during storage the per-
oxide complexes can decompose: in this case the
w(OꢁO) bands in the IR spectra disappear, while the
−
1
intensity of PꢀO stretching at 1120 and 1160 cm
increases clearly indicating the oxidation of
triphenylphosphine [28a,30]. Such process has already
been studied and described for the Wilkinson catalyst,
Fig. 4. H-bonding interconnection between two anions in 4.
labile COD ligand by PPh3 with the formation of
[Rh(CO)I(PPh ) ] [31] and in the case of interaction
3 2
[
RhQ(PPh ) ] intermediates analogous to those re-
between [Rh(acac)(CO)(PPh )] with salicilyc acid [28c].
3
3
2
ported in Refs. [11,26] which in this case can be de-
tected only by P{ H}-NMR spectroscopy but are very
sensitive toward even negligible traces of oxygen. The
It is well known that p-acceptors such as COD, NBD,
COE, CO and ethylene stabilise Rh in the low oxida-
tion state +1, so that the compounds are air stable to
oxidation during storage. Even the mixed ligand com-
3
1
1
[
RhQ(PPh ) ] intermediates immediately reacts with O
3
2
2
yielding the Rh(III) species [RhQ(O )(PPh ) ] 8–10
plexes containing both CO and PPh ligands are suffi-
2
3 2
3
(
Scheme 3). In fact, in the IR spectra of 8–10 there are
ciently air stable. PPh acts as a chemical Janus toward
3
−
1
stretching bands at 850–890 cm
of h -peroxo-groups [28]. This reaction was also moni-
tored by NMR: two double doublets at ca. 34 and 37
due to the presence
Rh centre. From one side, refluxing RhCl in ethanol in
3
2
the presence of the excess of PPh3 is an important
method to prepare the Wilkinson catalyst or
[Rh(PPh ) Cl] , i.e. to stabilise Rh in +1 state, since
3
1
103
ppm ( P– Rh coupling constants of ca. 150.5 and
3
2
2
Scheme 3.

1
2
C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
Scheme 4.
both Rh(PPh ) Cl and [Rh(PPh ) Cl] are sufficiently
air stable as solids. On the other hand the full substitu-
dppf-O ligand is formed. This reaction was also moni-
2
3
3
3 2
2
31
31
tored by P-NMR spectra. After 15 min the P-NMR
+
tion of the labile soft carbon p-acceptor (CO, COD) by
spectrum exhibited signals typical of [Rh(dppf)
2
]
spe-
PPh results in a complete destabilisation of Rh toward
cies [40]. After 2 h signals analogous to those found in
the spectrum of 11 appeared which disappeared com-
pletely after 24 h. At this point only a broad signal
3
oxidation, so that the isolation of Rh(PPh ) (dik) com-
3
2
plexes in many cases is not possible. Recently such
complexes with some tertiary phosphines were shown to
be thermodynamically unstable [32]. So, the only possi-
ble way to stabilise Rh(I) is to use a large excess of
phosphine as it was shown to be a method used in the
preparation of the Wilkinson catalyst from
typical of oxidised dppf-O was present. Unfortunately
2
this compound is soluble only in chlorinate solvents, in
which it decomposes to not clearly identifiable species.
The oxidative addition of allyl bromide to complex 1
has been studied. It was shown that in the absence of
PPh no oxidation occurs, but the reaction proceeds via
[Rh(COD)Cl]2.
3
the substitution pathway quantitatively giving
In the literature there are indications on the existence
of mixed ligand Rh(I) cycloalkadiene (COD, NBD)–
[Rh(COD)(m-Br)]2 (14). In the presence of PPh3 the
yellowish colour of the solution of 1 in THF turns to
brownish immediately and a mixture of oxidation prod-
ucts forms. Further investigation of this reaction will be
reported elsewhere.
PPh complexes such as [Rh(COD)(PPh ) ]Cl [33] or
3
3 2
[
Rh(NBD)(PPh ) ]ClO [34]. Such complexes were re-
3 2 4
ally isolated and characterised in the case of less donor
tri(p-fluorophenyl)phosphine [35] and chelating alkoxy
The structure of [Rh(COD)Br] (14) resembles that of
2
aryl-
and
alkylarylphosphines
as
tris(2,4,6-
the corresponding chloride [41]. However, both struc-
tures are not isomorphous crystallographically. The
two independent Rh atoms in 14 are lying in the mirror
plane of the molecule (Fig. 5). Both Rh atoms have a
slightly distorted square-planar environment with two
bromine atoms and two centres of the double bonds.
trimethoxyphenyl)phosphine [36] or benzylbis(2-
ethoxyethyl)phosphine [37]. It has also been shown [8]
that alyphatic phosphines such as PMe , being more
3
basic withrespect to PPh , completely substitute cy-
3
clooctadiene in Rh(COD)(dik) giving (PMe ) Rh(dik)
3
2
or even ionic [Rh(PMe) ]dik.
4
The average RhꢁC distance, 2.116 A
corresponding values, 2.12 A, calculated from the data
in Ref. [41]. As expected, the RhꢁBr distances, 2.54 A
are considerably longer than those of RhꢁCl, 2.38 A
41]. Two square-planar Rh fragments are folded
,
, is close to the
The reactivity of RhꢁCOD complexes toward biden-
tate chelating phosphine has also been investigated. The
interaction of 1 with dppf resulted in the formation of
the oxidation product 11 (Scheme 4). In fact the sharp
,
,
,
,
[
−
1
band at 874 cm in the IR spectrum of 11 is typical of
around the Br···Br line by 31°. This feature has not
been noticed in the original publication [41] where the
whole dimeric fragment was considered as nearly
planar.
2
h -peroxo-complexes, while the CꢁO, CꢁC adsorptions
are similar to those found in the spectrum of 1, indicat-
31
ing the chelating nature of acylpyrazolone. The P-
NMR spectrum of 11 exhibit a signal similar to that
found in Rh(III) species containing not-oxidised dppf
ligands [38].
When 3 reacts with an excess of dppe the complex
T
[
Rh(dppe) O ]Q
(12) was formed (Scheme 5).
2
2
Analogous complexes [Rh(dppe) O ]X have been re-
2
2
−
−
4
ported (X=Cl and BF ). The spectral data of our
complex are in accordance with those reported in Ref.
[
39].
Finally when compound 3 reacts with an excess of
dppf and the reaction is carried out for more than 24 h,
then compound 13 (Scheme 6) containing the oxidised
Scheme 5.

C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
13
Scheme 6.
5
. Supplementary material
Crystallographic data for structural analysis have
been deposited with the Cambridge Crystallographic
Data Centre, CCDC nos. 173303–173305. Copies of
this information may be obtained free of charge from
The Director, CCDC, 12 Union Road, Cambridge,
CB2 1EZ, UK (Fax: +44-1223-336033; e-mail: de-
posit@ccdc.cam.ac.uk or www: http://www.ccdc.
cam.ac.uk).
Acknowledgements
Thanks are due to the university of Camerino,
‘Carima Foundation’, INTAS (research project 00-469
Fig. 5. Molecular structure of derivative 14.
and individual grant YS-220 for Dr Andrei Drozdov)
and Russian Foundation for Basic Research (research
grant 00-03-32662) for financial support.
4. Conclusions
References
It was shown that the additional donor atoms in 4-R
group of acylpyrazolones do not change the structure,
geometry and reactivity of Rh(I) complexes. Chelating
N-donor ligands such as bipy and phen replace
acylpyrazolonate anion in [Rh(COD)Q] derivatives giv-
ing ionic complexes. In the presence of the phosphines
[
[
[
1] A.M. Trzeciak, J.J. Zi o´ lkowski, Coord. Chem. Rev. 190–192
(
1999) 883.
2] M.C. Simpson, D.J. Cole-Hamilton, Coord. Chem. Rev. 155
(1996) 163.
3] (a) A.T. Teleshev, N.V. Kolesnichenko, N.A. Markova, G.V.
Terekhova, V.I. Kurkin, E.V. Slivinskii, E.E. Nifant’ev,
Neftekhimiya 39 (1999) 203;
(
PPh , dppe, dppf), rhodium centre becomes more sen-
3
sitive toward oxidation. Rh(I) derivatives were iso-
lated only in the case of dppf due to the sterical
hindrances in dppf that make a complex more stable to
oxidation.
(
b) L.A. van der Veen, P.C.J. Kamer, P.W.N.M. van Leeuwen,
Organometallics 18 (1999) 4765;
c) S. Deerenberg, P.C.J. Kamer, P.W.N.M. van Leeuwen,
Organometallics 19 (2000) 2065;
(

1
4
C. Pettinari et al. / Journal of Organometallic Chemistry 651 (2002) 5–14
d) M. Laly, R. Broussier, B. Gautheron, Tetrahedron Lett. 41 (e) J.G. Donkervoort, M. B u¨ hl, J.M. Ernsting, C.J. Elsevier,
(
(
(
(
(
2000) 1183;
Eur. J. Inorg. Chem. (1999) 27.
e) R.W. Hoffmann, D. Br u¨ ckner, V.J. Gerusz, Heterocycles 52
2000) 121;
[23] (a) V. Garcia, M.A. Garralda, L. Ibarlucea, Polyhedron 7 (1988)
1067;
f) M.A. Esteuelas, J. Herrero, M. Martin, L.A. Oro, V.M. Real,
(b) V. Garcia, M.A. Garralda, L. Ibarlucea, Trans. Met. Chem.
10 (1985) 288;
J. Organomet. Chem. 599 (2000) 178.
4] (a) K. Wajda-Hermanowicz, F.P. Pruchnik, Trans. Met. Chem.
3 (1998) 22;
b) K. Wajda-Hermanowicz, F.P. Pruchnik, Trans. Met. Chem.
3 (1998) 101.
[
[
(c) M.A. Garralda, L. Ibarlucea, J. Organomet. Chem. 311
(1986) 225;
1
(
(d) M.A. Garralda, R. Hern a´ ndez, L. Ibarlucea, M.I. Arr `ı ortua,
M.K. Urtiaga, Inorg. Chim. Acta 232 (1995) 9.
1
5] (a) F.P. Pruchnik, P. Smole n´ ski, K. Wajda-Hermanowicz, J.
[
[
24] M. Moszner, S. Wolowiec, A. Tr o¨ sch, H. Vahrenkamp, J.
Organomet. Chem. 595 (2000) 178.
25] B.T. Heaton, C. Jacob, J. Markopoulos, O. Markopoulou, J.
N a¨ hring, C.-K. Skylaris, A.K. Smith, J. Chem. Soc. Dalton
Trans. (1996) 1701.
Organomet. Chem. 570 (1998) 63;
(b) A.M. Trzeciak, T. Głowiak, R. Grzybek, J.J. Zi o´ łkowski, J.
Chem. Soc. Dalton Trans. (1997) 1831.
[
[
6] J.R. Bleeke, A.J. Donaldson, Organometallics 5 (1986) 2401.
7] J.G. Leipoldt, G.J. Lamprecht, E.C. Steynberg, J. Organomet.
Chem. 43 (1990) 239.
[
[
[
26] K. Timmer, D.H.M.M. Thewissen, Inorg. Chim. Acta 100 (1985)
2
35.
[
[
8] Z. Duan, M.J. Hampden-Smith, E.N. Duesler, Polyhedron 13
27] A. Felix, A.R. Guadalupe, S.D. Huang, Z. Krist, New. Cryst.
Struct. 214 (1999) 463.
28] (a) C.W. Dudley, G. Read, P.J.C. Walker, J. Chem. Soc. Dalton
Trans. (1974) 1927;
(
1994) 609.
9] K. Angermund, W. Baumann, E. Dinjus, R. Fornika, H. G o¨ rls,
M. Kessler, C. Kr u¨ ger, W. Leitner, F. Lutz, Chem. Eur. J. 3
(
1997) 755.
(
b) H. Suzuki, S. Matsuura, Y. Moro-oka, T. Ikawa, Chem.
Lett. (1982) 1011;
c) E. Mieczy n´ ska, A.M. Trzeciak, J.J. Zi o´ łkowski, T. Lis, J.
Chem. Soc. Dalton Trans. (1995) 105;
[
[
10] F. Bonati, L.A. Oro, M.T. Pinillos, Polyhedron 4 (1985) 357.
11] C. Pettinari, F. Accorroni, A. Cingolani, F. Marchetti, A. Cas-
setta, L. Barba, J. Organomet. Chem. 566 (1998) 187.
(
[
[
12] G. Giordano, R.H. Crabtree, Inorg. Synth. 28 (1990) 88.
13] C. Pettinari, F. Marchetti, A. Cingolani, D. Leonesi, S. Troy-
anov, A. Drozdov, J. Chem. Soc. Dalton Trans. (1999) 1555.
14] (a) J. Chatt, L.M. Venanzi, J. Chem. Soc. (1957) 4735;
(
(
(
d) G.L. Geoffroy, M.E. Keeney, Inorg. Chem. 16 (1977) 205;
e) M.J. Bennett, P.B. Donaldson, Inorg. Chem. 16 (1977) 1581;
f) F. Sakurai, H. Suzuki, Y. Moro-oka, T. Ikawa, J. Am. Chem.
[
[
Soc. 102 (1980) 1749;
g) H.F. Haarman, F.R. Bregman, P.W.N.M. van Leeuwen, K.
Vrieze, Organometallics 16 (1997) 979;
(
(
b) D.M. Adams, P.J. Chandler, J. Chem. Soc. A (1969) 588;
c) J.V. Kingston, G.R. Scollary, J. Chem. Soc. A (1971) 3399.
(
15] (a) G.M. Sheldrick, SHELXS 86, University of G o¨ ttingen, G o¨ ttin-
(
(
h) R.L. Augustine, J. Van Peppen, Chem. Commun. (1970) 497;
i) Another route for transformation of peroxo-complex during
gen, Germany, 1986;
(b) G.M. Sheldrick, SHELXL 93, University of G o¨ ttingen, G o¨ ttin-
the storage is the formation of peroxocarbonate through OꢁO
bond cleavage and CO2 insertion. See: M. Aresta, I. Tommasi,
E. Quaranta, C. Fragale, J. Mascetti, M. Tranquille, F. Galan,
M. Fouassier, Inorg. Chem. 35 (1996) 4254;
gen, Germany, 1993.
[
[
[
16] B.S. Jensen, Acta Chem. Scand. 13 (1959) 1347.
17] W. Holzer, K. Mereiter, B. Plagens, Heterocycles 50 (1999) 799.
18] (a) M.A. Bennett, R.J.H. Clark, D.L. Milner, Inorg. Chem. 6
(
(
j) M. Aresta, A. Dibenedetto, I. Tommasi, Eur. J. Inorg. Chem.
2001) 1801.
(
(
1967) 1647;
b) A.C. Jesse, M.A.M. Meester, D.J. Stufkens, K. Vrieze, Inorg.
[
29] H.G.M. Edwards, I.P. Lewis, P.H. Turner, Inorg. Chim. Acta
16 (1994) 191.
Chim. Acta 26 (1978) 129;
(
(
2
c) D.W. Wertz, M.A. Moseley, Inorg. Chem. 19 (1980) 705;
d) M.A. Bennett, J.D. Saxby, Inorg. Chem. 7 (1968) 321.
[
[
30] G.B. Deacon, J.H.S. Green, Spectrochim. Acta A 25 (1969) 355.
31] M. Selke, W.L. Karney, S.I. Khan, C.S. Foote, Inorg. Chem. 34
[
19] (a) M. Chatt, L.A. Duncanson, J. Chem. Soc. (1953) 2939;
b) H.C. Volger, M.M.P. Gaasbeek, H. Hogeveen, K. Vrieze,
(
1995) 5715.
(
[
32] W. Simanko, K. Mereiter, R. Schmid, K. Kirchner, A.M. Trze-
ciak, J. Zi o´ łkowski, J. Organomet. Chem. 602 (2000) 59.
33] G.K. Anderson, R. Kumar, Inorg. Chim. Acta 146 (1988) 89.
34] R.R. Scronck, J.A. Osborn, J. Am. Chem. Soc. 93 (1971) 2397.
35] M. Iglesias, C. del Pino, A. Corma, S. Garc ´ı a-Blanco, S.M.
Carrera, Inorg. Chim. Acta 127 (1987) 215.
Inorg. Chim. Acta 3 (1969) 145.
[
[
20] P.A. Tucker, W. Scutcher, D.R. Russell, Acta Crystallogr. B 31
[
[
[
(
1975) 592.
21] (a) W.A. Fordyce, G.A. Crosby, Inorg. Chem. 21 (1982) 1023;
(
(
(
b) W.A. Fordyce, K.H. Pool, G.A. Crosby, Inorg. Chem. 21
1982) 1027;
c) G. Mestroni, A. Camus, G. Zassinovich, J. Organomet.
[
[
36] K.R. Dunbar, S.C. Haefner, C.E. Uzelmeier, A. Howard, Inorg.
Chim. Acta 240 (1995) 527.
37] S.J. Chadwell, S.J. Coles, P.G. Edwards, M.B. Hursthouse, J.
Chem. Soc. Dalton Trans. (1995) 3551.
Chem. 65 (1974) 119;
d) G. Clauti, G. Zassinovich, G. Mestroni, Inorg. Chim. Acta
12 (1986) 103;
e) B. Crociani, F. Di Bianca, M. Paci, T. Boschi, Inorg. Chim.
(
1
(
[
[
38] J.-F. Ma, Y. Yamamoto, J. Organomet. Chem. 574 (1999) 148.
39] (a) B.R. James, D. Mahajan, Can. J. Chem. 58 (1980) 996;
(b) A. Morvillo, M. Bressan, Inorg. Chim. Acta 121 (1986) 219;
(c) J.S. Miller, K.G. Caulton, J. Am. Chem. Soc. 97 (1975) 1067;
(d) J.A. McGinnety, N. Payne, J.A. Ibers, J. Am. Chem. Soc. 91
(1969) 6301.
Acta 145 (1988) 253.
[
22] (a) E. Anzuela, M.A. Garralda, R. Hern a´ ndez, L. Ibarlucea, E.
Pinilla, M.A. Monge, Inorg. Chim. Acta 185 (1991) 211;
(b) M.A. Esteruelas, L.A. Oro, M.C. Apreda, C. Foces-Foces, F.
Cano, R.M. Claramunt, C. Lopez, J. Elguero, M. Begtrup, J.
Organomet. Chem. 344 (1988) 93;
[40] (a) U. Casellato, B. Corain, R. Graziani, B. Longato, P. Pilloni,
Inorg. Chem. 29 (1990) 1193;
(
c) M. Cano, J.A. Campo, J.V. Heras, E. Pinilla, C. Rivas,
Polyhedron 13 (1994) 2463;
d) V. Gayathri, E.G. Leelamani, N.M.N. Gowda, G.K.N.
Reddy, Trans. Met. Chem. 25 (2000) 450;
(b) V. Di Noto, G. Valle, B. Zarli, B. Longato, G. Pilloni, B.
Corain, Inorg. Chim. Acta 233 (1995) 165.
(
[41] J.A. Ibers, R.G. Snyder, Acta Crystallogr. 15 (1962) 923.