Preparation and reactions of the (pentamethylcyclopentadienyl)rhodium(III) complexes bearing 1,1′-bis(diphenylphosphinomethyl)ferrocene (dpmf) or 1,1′-bis(diphenylphosphino)ferrocene (dppf)

Article abstract of DOI:10.1016/S0022-328X(98)00939-5

Reactions of [Cp*RhCl₂]₂ with 1,1′-bis(diphenylphosphinomethyl)ferrocene (dpmf) or 1,1′-bis(diphenylphosphino)ferrocene (dppf) gave the bridged complex [Cp*RnCl₂]₂(μ-diphos) (1: diphos=dpmf; 2: diphos=dppf). Rea

Full text of DOI:10.1016/S0022-328X(98)00939-5

Journal of Organometallic Chemistry 574 (1999) 148–154
Preparation and reactions of the
(pentamethylcyclopentadienyl)rhodium(III) complexes bearing
1,1%-bis(diphenylphosphinomethyl)ferrocene (dpmf) or
1,1%-bis(diphenylphosphino)ferrocene (dppf)ꢀ
Jian-Fang Ma 1, Yasuhiro Yamamoto *
Department of Chemistry, Faculty of Science, Toho Uni6ersity, Miyama, Funabashi, Chiba 274-8510, Japan
Received 4 July 1998; received in revised form 24 August 1998
Abstract
Reactions of [Cp*RhCl2]2 with 1,1%-bis(diphenylphosphinomethyl)ferrocene (dpmf) or 1,1%-bis(diphenylphosphino)ferrocene
(dppf) gave the bridged complex [Cp*RnCl2]2(v-diphos) (1: diphos=dpmf; 2: diphos=dppf). Reaction with dppf in the presence
of NaPF6 gave the cationic chelated [Cp*RhCl(dppf-P,P%)](PF6) complex 3. Complex 1 reacted with xylyl isocyanide (XylNC) in
the presence of NaPF6 to yield [Cp*Rh2Cl2(v-dpmf)(XylNC)2](PF6)2, 4, in low yield. [Cp*Rh(dppf-P,P%)(MeCN)](PF6)2, 5a, was
2
prepared from 3, NaPF6 and AgNO3 in MeCN. The acetonitrile ligand in this complex was replaced readily with Lewis bases (L),
such as CO and isocyanides, to form [Cp*Rh(dppf-P,P%)(L)](PF6)2, 5. Structures of 2, 3 and 5d (L=p-TosCH2NC) were
confirmed by X-ray analyses, in which their molecules have the piano stool structure. © 1999 Elsevier Science S.A. All rights
reserved.
Keywords: dpmf; dppf; Rhodium
1. Introduction
clinal, antiperiplanar, etc., when dppf co-ordinates to
the metals ([1]a).
The use of ferrocenyl phosphines as ligands in co-or-
dination chemistry and catalytic reactions is well-
known [1]. Many of the metal complexes of
1,1%-bis(diphenylphosphino)ferrocene (dppf) are catalyt-
ically active in some organic reactions, such as C–C
couplings [2], hydroformylation [3], etc. It has been
reported that the bite size and angle of dppf contribute
to catalytic activities [1] and the conformation of ferro-
cenyl moiety thus plays an important role. The ferro-
1,1%-Bis[(diphenylphosphino)methyl]ferrocene (dpmf)
formed by introduction of a methylene group between
the cyclopentadienyl ring and P atom is less rigid than
dppf. This paper is interested in differences of struc-
tures and reactivities between dppf and dpmf. As part
of ongoing studies, the preparation of dpmf, and palla-
dium and nickel complexes of dpmf, were reported and
they have macrocyclic dinuclear or tetranuclear struc-
tures bridged by two dpmf ligands [4]. The authors
recently reported the reactions of bis[dichloro(p6-
arene)ruthenium(II)] with dpmf or dppf [5]. They now
report the synthesis, structures and reactions of the
bridged or chelating complexes derived from the treat-
ment of dpmf or dppf with bis[dichloro(p5-pen-
tamethylcyclopentadienyl)rhodium(III)], [Cp*RhCl2]2,
bearing an isoelectronic structure with bis[dichloro(p6-
cenyl moiety in dppf takes
a wide variety of
conformations, such as synperiplanar, synclinal, anti-
ꢀ Dedicated to the memory of the late Professor Rokuro Okawara.
* Corresponding author. Tel.: +81-474-725-076; fax: +81-474-
751-855; e-mail: yamamoto@chem.sci.toho-u.ac.jp.
1 On leave from Changchun Institute of Applied Chemistry, Chi-
nese Academy of Sciences.
0022-328X/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved.
PII: S0022-328X(98)00939-5

J.-F. Ma, Y. Yamamoto / Journal of Organometallic Chemistry 574 (1999) 148–154
149
Table 1
Crystal
data
of
[(p5-C5Me5)2Rh2Cl2(v-dppf)]
2,
[(p5-C5Me5)RhCl(dppf-P,P%)](PF6)
3,
and
[(p5-C5Me5)Rh(dppf-P,P%)(p-
MeC6H5SO2CH2NC)](PF6) 5d
Compound
2
3
5d
Formula
C54H55P2Cl4FeRh2
1172.47
Red–violet
0.40×0.30×0.20
Triclinic
P1 (No. 2)
15.19(1)
16.836(9)
12.36(1)
104.75(5)
111.61(5)
95.39(5)
2780(4)
2
C44H43P3F6CLFeRh
972.94
C53H52NO2P4Fe12SFeRh
1277.69
Pink
0.40×0.30×0.20
Monoclinic
P21/n (No. 14)
16.203(5)
18.081(5)
20.350(4)
90.0
105.35(2)
90.0
5749(2)
4
1.476
7.64
Molecular weight
Color
Orange
0.40×0.20×0.10
Monoclinic
P21/n (No. 14)
14.987(2)
16.734(4)
16.025(2)
90.0
92.94(1)
90.0
4013(1)
4
Crystal size (mm3)
Crystal system
Space group
˚
a (A)
˚
b (A)
˚
c (A)
h (°)
i (°)
k (°)
3
˚
V (A )
Z
Dcalc. (g cm−3
)
1.400
5.38
1192
1.610
10.18
1976
v, (cm−1
F(000)
)
2592
No. of reflections
9811
7336
10 509
No. of data (I\3.0|(I))
No. of variables
4332
558
0.079; 0.097
2.73
2854
505
0.054; 0.062
1.51
2846
511
0.068; 0.075
1.98
a
R; Rw
GOFb
a R=ꢀ ꢁꢁFoꢁ−ꢁFcꢁꢁ/ꢀ ꢁFoꢁ and Rw=[ꢀ w(ꢁFoꢁ−ꢁFcꢁ)2/ꢀ wꢁFoꢁ ] (w=1/|2(Fo)).
2 1/2
b GOF=[ꢀ w(ꢁFoꢁ−ꢁFcꢁ)2/ꢀ (No−Nv)]1/2, where No=number of data, Nv=number of variables.
1
arene)ruthenium(II)]. A preliminary part of this study
has been described [6].
of 1 (42 mg, 70%). H-NMR(CDCl3): l (ppm) 1.29 (d,
J
J
PH=3.4 Hz, C5Me5), 3.19, 3.62 (s, C5H4), 3.67 (d,
PH=3.4 Hz, PCH2), 7.3–7.7 (m, Ph). 31P{1H}-NMR
(CDCl3): l (ppm) 33.86 (d, JRhP=141 Hz). Anal. Calc.
for C56H62C4P2FeRh2: C, 56.03; H, 5.21. Found: C,
56.26; H, 5.00.
2. Experimental
All reactions were carried out under nitrogen atmo-
sphere.
enyl)rhodium(III)] [7], dpmf [4], dppf [8] and
isocyanides (2,6-Me2C6H3NC (=XylNC), 2,4,6-
Me3C6H2NC (=MesNC)) [9] were prepared according
Complex [Cp*RhCl2]2(v-dppf) 2 (78%) was prepared
from the reaction of [Cp*RhCl2]2 with dppf according
to a method similar to that for 1. H-NMR (CDCl3, at
r.t.): l (ppm) 1.21 (d, JPH=3.4 Hz, C5Me5), ca. 4.0 (b,
C5H4), 7.2–7.9 (m, Ph); (at 50°C): l (ppm) 1.23 (d,
Bis[dichloro(p5-pentamethylcyclopentadi-
1
to
the
literature.
p-MeC6H4SO2CH2NC
(=
JPH=3.4 Hz, C5Me5), 4.07, 4.16 (b, C5H4), 7.2–7.8 (m,
TosCH2NC) was commercially available. (l)-3-(PhMe-
HCNHCO)C6H4NC was given by Miss F. Takei of
Osaka University. Dichloromethane and diethyl ether
were distilled over CaH2. The IR spectra were mea-
sured on an FT/IR-5300. NMR spectroscopy was car-
Ph). 31P{1H}-NMR (CDCl3 at r.t.): l (ppm) ca. 22 (b);
(at 50°): l (ppm) 22.98 (d, JRhP=146 Hz). Anal. Calc.
for C54H58C4P2FeRh2: C, 55.32; H, 4.99. Found:
C,54.72;H, 4.79.
1
ried out on a Bruker AC250. H-NMR spectra were
2.2. Preparation of [Cp*RhCl(dppf-P,P%)](PF6), 3
measured at 250 MHz and 31P{1H}-NMR spectra were
measured at 101 MHz using 85% H3PO4 as an external
reference.
To a solution of [Cp*RhCl2]2 (31 mg, 0.05 mmol)
and dppf (56 mg, 0.1 mmol) in a mixture of CH2C12 (5
ml) and acetone (5 ml), NaPF6 (84 mg, 0.5 mmol) was
added at r.t. After the mixture was stirred for 3 h, the
solvent was removed under reduced pressure. The
residue was extracted with CH2CI2 (2×10 ml). The
solution was concentrated to ca. 3 ml and diethyl ether
was added to give red–orange crystals of 3 (82 mg,
84%). IR (nujol): 841 cm−1 (PF6). 1H-NMR
(CD3COCD3): l (ppm) 1.20 (t, JPH=3.7 Hz, C5Me5),
2.1. Preparation of [Cp*RhCl2]2(v-dpmf), 1
To a solution of [Cp*RhCl2]2 (31 mg, 0.05 mmol) in
CH2Cl2 (10 ml), dpmf (29 mg, 0.05 mmol) was added at
room temperature (r.t.). After stirring for 2 h, the
solvent was reduced to ca. 3 ml under reduced pressure
and diethyl ether was added to give red–orange crystals

150
J.-F. Ma, Y. Yamamoto / Journal of Organometallic Chemistry 574 (1999) 148–154
Scheme 1. Reactions of [(p5-C5Me5)RhCl2]2 and its related complexes. (P—P=dmpf-P,P% for 1 and 4; dppf-P,P% for 2, 3 and 5: L=CO, RN).
4.27, 4.48, 4.53, 5.19 (s, C5H4), 7.5–7.9 (m, Ph).
31P{lH}-NMR (CD3COCD3): l (ppm) 37.94 (d, JRhP
145 Hz, dppf), −143.1 (sep. JPF=707 Hz, PF6). Anal.
Calc. for C44H43Cl2P3F6FeRh2: C, 57.07; H, 5.43.
Found: C, 56.65; H, 5.12.
31P{1H}-NMR (CD2Cl2): l (ppm) 39.69 (d, JRhP=123
Hz, dpmf), −142.5 (sep., JPF=711 Hz, PF6). Anal.
Calc. for C74H80Cl2N2P4F12FeRh2: C, 52.85; H, 4.79;
N, 1.67. Found: C, 52.69; H, 4.50; N, 1.67.
=
2.4. Preparation of [Cp*Rh(dppf-P,P%)(MeCN)](PF6)2,
5a
2.3. Preparation of
[Cp*Rh2Cl2(v-dpmf)(XylNC)2](PF6)2, 4
2
To a solution of 3 (97 mg, 0.10 mmol) and NaPF6
(84 mg, 0.5 mmol) in MeCN (20 ml), AgNO3 (17 mg,
0.1 mmol) was added at r.t. After stirring for 3 h, the
solvent was removed under reduced pressure. The
residue was extracted with CH2Cl2 (2×10 ml). The
solution was concentrated to ca. 5 ml and diethyl ether
was added to give brown crystals of 5a (86 mg, 77%).
IR (nujol): 2313, 2278 (CꢀN), 841 cm−1 (PF6). 1H-
NMR (CD3COCD3): l (ppm) 1.32 (t, JPH=3.9 Hz,
C5Me5), 3.43 (s, MeCN), 4.47, 4.64, 4.75, 4.92 (s,
C5H4), 7.7–8.0 (m, Ph). 31P{1H}-NMR (CD3COCD3):
l (ppm) 41.74 (d, JRhp=133 Hz, dppf), −143.1 (sep.,
To a solution of 1 (60 mg, 0.05 mmol) and xylyl
isocyanide (13 mg, 0.1 mmol) in a mixture of CH2Cl2 (5
ml) and acetone (5 ml), NaPF6 (84 mg, 0.5 mmol) was
added at r.t. After the mixture was stirred for 3 h, the
solvent was removed under reduced pressure. The
residue was extracted with CH2Cl2 (2×10 ml). The
solvent was removed to dryness and recrystallization of
the residual oil from MeOH/diethyl ether gave orange
crystals of 4 (8 mg, 11%). IR (nujol): 2170 (NꢀC), 841
cm−1 (PF6). 1H-NMR (CD2Cl2): l (ppm) 1.44 (d,
J
PH=3.6 Hz, C5Me5), 2.16 (s, o-Me), 2.60, 2.96, 3.15,
3.99 (s, C5H4), 333 (t, JHH=JPH=15 Hz, PCH), 3.79
(q, JHH=15 Hz, JPH=7.5 Hz, PCH), 7.0–7.8 (m, Ph).
JPF=707
Hz,
PF6).
Anal.
Calc.
for
Fig. 2. Structure of 3. The PF6 and hydrogen atoms were omitted for
Fig. 1. Structure of 2. Hydrogen atoms were omitted for clarity.
clarity.

J.-F. Ma, Y. Yamamoto / Journal of Organometallic Chemistry 574 (1999) 148–154
151
Analogously,
other
isocyanide
complexes
[Cp*Rh(dppf-P,P%)(RNC)](PF6)2 (5c: R=Mes; 5d:
R=p-TosCH2; 5e: 3-(l)-PhCHMeNHCO)C6H4)] were
prepared from the substitution reaction of 5a with the
appropriate isocyanide. 5c (pink, yield 95%): IR (nujol):
1
2153 (NꢀC), 837 cm−1 (PF6). H-NMR (CD3COCD3):
l (ppm) 1.49 (t, JPH=3.9 Hz, C5Me5), 2.41 (s, o-Me),
2.44 (s, p-Me), 4.60, 4.75, 4.79, 4.85 (s, C5H4), 7.26 (s,
m-H of MesNC), 7.8–8.0 (m, Ph). 31P{1H}-NMR
(CD3COCD3): l (ppm) 42.82 (d, JRhP=127 Hz, dppf),
−143.1 (sep., JPF=707 Hz, PF6). Anal. Calc. for
C54H54NP4F12FeRh: C, 52.83; H, 4.43; N, 1.14. Found:
C, 52.17; H, 4.48; N, 0.99.
5d (brown, yield 91%): IR (nujol): 2186 (NꢀC), 1595
(SO2), 843 cm−1 (PF6). 1H-NMR (CD3COCD3): l
(ppm) 1.49 (t, JPH=3.9 Hz, C5Me5), 2.57 (s, p-Me),
4.51, 4.65, 4.83, 5.12 (s, C5H4), 6.70 (s, CH2), 7.6–8.2
(m, Ph). 31P{1H}-NMR (CD3COCD3): l (ppm) 47.09
(d, JRhP=127 Hz, dppf), −143.1 (sep., JPF=707 Hz,
PF6). Anal. Calc. for C53H52NO2SP4F12FeRh: C, 49.82;
H, 4.10; N, 1.10. Found: C, 49.85; H, 3.92; N, 1.23.
5e (brown, yield 81%): IR (nujol): 3401 (NH), 2164
(NꢀC), 1657 (CꢁO), 839 cm−1 (PF6). 1H-NMR
(CD3COCD3): l (ppm) 1.53 (t, JPH=3.9 Hz, C5Me5),
1.63 (d, JHH=7.0 Hz, CH3), 4.54, 4.65, 4.89, 4.92 (s,
C5H4), 5.38 (q, JHH=7.0 Hz, CH), 7.3–8.6 (m, Ph).
Fig. 3. Structure of 5d. The PF6 and hydrogen atoms were omitted
for clarity.
C46H46N2P4F12FeRh: C, 49.18; H, 4.13; N, 1.25.
Found: C, 48.82; H, 3.84; N, 1.21.
2.5. Preparation of [Cp*Rh(dppf-P,P%)(XylNC)](PF6)2,
5b
To a solution of 5a (25 mg, 0.022 mmol) in CH2Cl2
(10 ml), xylyl isocyanide (4 mg, 0.03 mmol) was added
at r.t. After stirring for 2 h, the solution was concen-
trated to ca. 3 ml and diethyl ether was added to give
pink crystals of 5b (22 mg, 80%). IR (nujol): 2147
31P{1H}-NMR (CD3COCD3): l (ppm) 47.14 (d, JRhP
=
127 Hz, dppf), −143.1 (sep., JPF=707 Hz, PF6). Anal.
Calc. for C60H57N2OP4F12FeRh: C, 54.07; H, 4.31; N,
2.10. Found: C, 53.62; H, 4.20; N, 2.22.
1
(NꢀC), 841 cm−1 (PF6). H-NMR (CD2Cl2): l (ppm)
1.32 (t, JPH=3.9 Hz, C5Me5), 2.30 (s, o-Me), 4.46,
4.54, 4.57 (s, C5H4), 7.3–8.0 (m, Ph). 31P{1H}-NMR
(CD2Cl2): l (ppm) 43.22 (d, JRhP=127 Hz, dppf),
−142.6 (sep., JPF=713 Hz, PF6). Anal. Calc. for
C53H52Np4F12Rh: C, 52.45; H, 4.32; N, 1.15. Found: C,
51.96; H, 4.08; N, 1.15.
2.6. Preparation of [Cp*Rh(dppf-P,P%)(CO)](PF6)2, 5f
Through a solution of 5a (25 mg, 0.022 mmol) in
CH2Cl2 (10 ml), CO was bubbled for 10 min at r.t.
After stirring for 1 h, the solution was concentrated to
ca. 3 ml and diethyl ether was added to give brown
crystals of 5f (12 mg, 53%). IR (nujol): 2074 (CꢀO), 839
Table 2
Selected bond lengths and angles of [(p5-C5Me5)2Rh2Cl2(v-dppf)] 2a
1
cm−1 (PF6). H-NMR (CD3COCD3): l (ppm) 1.62 (t,
J
PH=4.1 Hz, C5Me5), 4.62, 4.80, 5.00, 5.26 (s, C5H4),
˚
Bond length (A)
RhꢂCl(1)
7.8–8.1 (m, Ph). 31P{1H}-NMR (CD3COCD3): l (ppm)
49.98 (d, JRhP=122 Hz, dppf), −143 2 (sep., JPF=707
Hz, PF6). Anal. Calc. for C45H43OF12P4FeRh: C, 48.67;
H, 3.90. Found: C, 48.65; H, 4.12.
2.394(5) RhꢂCl(2)
2.388(5)
2.05
RhꢂP(1)
2.349(5)
RhꢂCav(Cp*)
2.19
FeꢂCav(Cp)
Bond angles (°)
Cl(1)ꢂRhꢂCl(2)
Cl(2)ꢂRhꢂP(1)
RhꢂP(1)ꢂC(17)
C(11)ꢂP(1)ꢂC(17)
C(17)ꢂP(1)ꢂC(23)
2.7. Crystallography
92.5(2) Cl(1)ꢂRhꢂP(1)
89.9(2) RhꢂP(l)ꢂC(11)
119.3(6) RhꢂP(l)ꢂC(23)
100.7(8) C(ll)ꢂP(1)ꢂC(23)
103.8(8) C(23)ꢂFeꢂC(28)
88.1(2)
110.2(6)
116.3(6)
104.5(7)
158.6(7)
Complexes 2, 3 and 5d were recrystallized from
CH2Cl2/diethyl ether. Cell constants were determined
from 15–20 reflections on a Rigaku four-circle auto-
mated AFC5S diffractometer. The crystal along with
data collection parameters are summarized in Table 1.
Data collection was carried out on a Rigaku AFC5S
diffractometer. Intensities were measured by the 2q–ꢀ
scan method using graphite-monochromated Mo–Kh
Torsion angle (°)
RhꢂP(1)ꢂC(23)ꢂFe
P(1)ꢂC(23)
−84(1)
72(2)
RhꢂP(2)ꢂC(28)ꢂFe
P(2)ꢂC(28)
−84(1)
74(2)
ꢂFeꢂC(28)
ꢂFeꢂC(23)
a Cp*=C5Me5, Cp=C5H4.
˚
radiation (u=0.71069 A). Throughout the data collec-

152
J.-F. Ma, Y. Yamamoto / Journal of Organometallic Chemistry 574 (1999) 148–154
Table 3
MeOC6H3)] [13]. Arbitrary h- or i-protons of the
ferrocenyl rings of dpmf complex 1 showed two singlets
at l 3.19 and 3.62 ppm, whereas those of dppf 2
appeared at ca. l 4 ppm as a broad peak, in which h-
and i-protons could not be distinguished within the
NMR time scale at ambient temperature. When it was
measured at 50°C, the spectrum separated as two broad
peaks at l 4.07 and 4.16 ppm. In the 31P{1H}-NMR
spectra, complex 1 showed a doublet at l 33.86 ppm
(JRhP=141.0 Hz), but 2 showed a broad peak at l
21.80 ppm without showing a clear JPH coupling con-
Selected bond lengths and angles of [(p5-C5Me5)RhCl(dppf-
P,P%)](PF6) 3a
˚
Bond length (A)
RhꢂCl(1)
RhꢂP(2)
2.411(3)
2.365(3)
2.02
RhꢂP(1)
RhꢂCav(Cp)
2.364(3)
2.25
FeꢂCav(Cp)
Bond angle (°)
Cl(1)ꢂRhꢂP(1)
P(1)ꢂRhꢂP(2)
RhꢂP(2)ꢂC(6)
P(1)ꢂC(1)ꢂFe
88.9(1)
95.6(1)
120.4(4)
131.5(6)
Cl(1)ꢂRhꢂP(2)
RhꢂP(1)ꢂC(1)
C(1)ꢂFeꢂC(6)
P(2)ꢂC(6)ꢂFe
90.0(1)
119.6(4)
107.4(4)
129.7(6)
1
stant value, as well as in the H-NMR spectrum. The
spectrum at 50°C showed a doublet consisting of
Torsion angle (°)
RhꢂP(1)ꢂC(1)ꢂFe −04(1)
P(1)ꢂC(1)
RhꢂP(2)ꢂC(6)ꢂFe
P(2)ꢂC(6)
26.3(10)
0.1(9)
J
RhP=146.2 Hz. The elemental analysis and spectro-
−0.8(10)
scopic results showed that the molecule has a dimeric
structure bridged by the dpmf or dppf ligand. The
X-ray analysis of 2 supported the proposed structure
(Fig. 1).
ꢂFeꢂC(6)
ꢂFeꢂC(1)
a Cp*=C5Me5, Cp=C5H4.
When [Cp*RhCl2]2 was treated with two equivalents
of dppf in the presence of excess NaPF6 at r.t., red–or-
ange crystals, 3, formulated as [Cp*RhCl(dppf)](PF6)
were obtained in high yield. Complex 3 was also pre-
pared by the reaction of 2 with dppf in the presence of
NaPF6. The IR spectrum showed a strong peak at 841
tion, the intensities of the three standard reflections
were measured every 200 reflections as a check of the
stability of the crystals and no decay was observed.
Intensities were corrected for Lorentz and polarization
effects. The absorption correction was made with em-
pirical „ rotation. Atomic scattering factors were taken
from the usual tabulation of Cromer and Waber [10].
Anomalous dispersion effects were included in Fcalc [11];
the values of Df % and Df %% were those of Creagh and
McAuley [12]. All calculations were performed using
the teXsan crystallographic software package of the
Molecular Structure Corporation.
1
cm−1 due to a PF6 group. The H-NMR spectrum in
CD3COCD3 showed a triplet at l 1.20 ppm for the Cp*
protons and four singlets in the range from l 4.2 to 5.2
ppm for the ferrocenyl ring protons, as has been ob-
served in [(p6-arene)RuCl(dppf P,P%)](PF6) having the
chelated structure [5]. The X-ray analysis showed the
dppf chelated structure (Fig. 2). A similar reaction with
dpmf was carried out in the presence of excess NaPF6,
and a trace of yellow powder was obtained, but it could
The structures of 2, 3 and 5d were solved by Patter-
son methods (DIRDIF92) and refined by a full-matrix
least-squares methods based on F values. All non-hy-
drogen atoms for 2 and 3 were refined anisotropically,
and hydrogen atoms were calculated at the ideal posi-
Table 4
Selected bond lengths and angles of [(p5-C5Me5)Rh(dppf-P,P%)(p-
MeC6H4SO2CH2NC)] (PF6)2 5da
˚
tions with the CꢂH distance of 0.95 A. For 5d, 33
carbon atoms were refined isotropically and other non-
hydrogen atoms, anisotropically. Final difference
˚
Bond length (A)
RhꢂP(1)
2.387(4) RhꢂP(2)
2.397(5)
Fourier syntheses of 2 and 3 had no peak greater than
−3
˚
2.08 eA
.
RhꢂC(45)
N(1)ꢂC(46)
S(1)ꢂO(1)
2.02(2) C(45)ꢂN(1)
1.37(2) C(46)ꢂS(1)
1.41(1) S(1)ꢂO(2)
1.10(2)
1.81(2)
1.40(1)
2.01
RhꢂCav(Cp*)
2.27
FeꢂCav(Cp)
3. Results and discussion
Bond angle (°)
P(1)ꢂRhꢂP(2)
P(2)ꢂRhꢂC(45)
RhꢂP(2)ꢂC(1)
P(1)ꢂC(6)ꢂFe
RhꢂC(45)ꢂN(1)
N(1)ꢂC(46)ꢂS(1)
C(46)ꢂS(1)ꢂO(2)
C(47)ꢂS(1)ꢂO(2)
97.0(2)
89.4(5)
119.3(5)
P(1)ꢂRhꢂC(45)
RhꢂP(1)ꢂC(6)
C(1)ꢂFeꢂC(6)
90.8(5)
118.2(6)
110.3(7)
126.8(9)
178(1)
3.1. Reactions of [Cp*RhCl2]2 with dpmf or dppf
When [Cp*RhCl2]2 was treated with dpmf or dppf in
a 1:1 ratio at r.t., red–orange crystals, formulated as
[Cp*RhCl2]2(dpmf) 1 or [Cp*RhCl2]2(dppf) 2, were ob-
131.9(10) P(2)ꢂC(1)ꢂFe
170(1)
109(1)
106.8
C(45)ꢂ(N1)ꢂC(46)
C(46)ꢂS(1)ꢂ0(1)
C(47)ꢂS(1)ꢂ0(1)
106.5(9)
109.9(9)
1
tained in ca. 70% yields (Scheme 1). In the H-NMR
110.0(8)
spectra (CDCl3) the pentamethylcyclopentadienyl
groups appeared at l 1.29 ppm for 1 and l 1.21 ppm
for 2 as a doublet consisting of the coupling constant
value of JPH=3.4 Hz. A similar P–H coupling behav-
ior has been observed in Cp*RhCl2[PPh2(2-O-6-
Torsion angle (°)
RhꢂP(1)ꢂC(6)ꢂFe
P(1)ꢂC(6)ꢂFeꢂC(1)
−14(1)
−7(1)
RhꢂP(2)ꢂC(1)ꢂFe
P(2)ꢂC(1)ꢂFeꢂC(6)
33(1)
3(1)
a Cp*=C5Me5; Cp=C5H4.

J.-F. Ma, Y. Yamamoto / Journal of Organometallic Chemistry 574 (1999) 148–154
153
Table 5
Structural parameters of the ferrocenyl skeleton
~, (°)a
q (°)b
lP (°)c
CAꢂFeꢂCB (°)
P···P (A)
Conformation
˚
Complex
2
3
5d
142.9
3.0
−2.5
3.33
2.95
0.97
−0.28, −0.25
−0.17, −0.13
−0.06, −0.23
158.6(7)
107.4(4)
110.3(7)
6.84
3.50
3.58
Anticlinal (eclipsed)
Synperiplanar
Synperiplanar
a The torsion angle is defined as CAꢂXAꢂXBꢂCB, where CA is carbon atom in Cp ring A that is bonded to a P atom (likewise for CB), and XA
and XB are the centroids of the two Cp rings.
b q is the dihedral angle between the two Cp rings.
c lP is the deviation of the linked P atom from the same plane. A positive sign means that the P atom is on the same side of the Cp* ring as
the Fe atom.
not be characterized. No chelated complexes were
obtained.
order as MeCNBMesNCBTosCH2NC, (l)-3-(PhCH-
MeNHCO)C6H3NCBCO, and a similar fashion was
also observed for the chemical shift of the methyl
protons on the Cp* ring. Increase of y-acceptor ability
of ligands was accompanied by the result of the down-
field shift of the chemical shift of the Cp* protons and
the P nuclei. This suggested that the electron density on
the P and Cp* ring decreased with increase of y-accep-
tor ability. A similar trend has been observed in the
chelated diphosphine complexes, [(p6-arene)Rh(diphos)]-
(BF4) [15].
3.2. Reactions of the dpmf and dppf complexes (1, 2
and 3)
When complex 1 was treated with xylyl isocyanide in
the presence of NaPF6, replacement of a Cl anion with
the isocyanide occurred to give red–orange crystals, 4,
formulated as [Cp*2 Rh2Cl2(XylNC)2(dpmf)](PF6)2 from
the elemental analysis, as depicted in Scheme 1. How-
ever, a similar reaction with dppf complex 2 did not
give any isolatible complexes. The IR spectrum of 4
3.3. Structures of 2, 3 and 5d
showed two characteristic bands at 2170 and 841 cm−1
,
suggesting the presence of the terminal isocyanide and
PF6 groups.
The selected bond lengths and angles, and structural
parameters of the ferrocenyl skeleton are summarized
in Tables 2–5. The conformations of ferrocenyl skele-
ton are classified by six categories from the torsion
angles of ~ [1], in which the conformation between two
ferocenyl rings are anticlinal (eclipsed) with the P···P
An attempt to replace a Cl anion of 3 with an
isocyanide in the presence of NaPF6 was carried out in
a mixture of CH2Cl2 and MeOH, and the starting
material 3 was recovered. However, when AgNO3 was
added to a mixture of 3 and NaPF6 in MeCN, brown
crystals of 5a, formulated as [Cp*Rh(dppf)(MeCN)]
(PF6)2, were obtained in 77% yield. The IR spectrum
showed the presence of the CꢀN bond and PF6 group.
The 1H-NMR spectrum in CD3COCD3 indicated a
triplet at l 1.32 ppm and a singlet at l 3.43 ppm,
assignable to the Cp* and acetonitrile protons, respec-
tively. Each of the ferrocenyl protons also appeared as
four singlets derived from the chelated structure. A
˚
separation of 6.84 A for 2 and synperiplanar with the
˚
P···P separation of ca. 3.5 A for 3 and 5d. The dihedral
angles between two ferrocenyl rings are 1–3°, not being
different from those found in arene–ruthenium com-
plexes containing dpmf or dppf ligand [5].
4. Supplementary materials
similar
acetonitrile
complex
of
ruthenium(I),
[Cp*Ru(dppf)(MeCN)](BF4)] has been prepared from
the reaction of [Cp*RuCl(dppf)] with AgBF4 in MeCN
[14]. The acetonitrile ligand of 5a was readily replaced
with Lewis bases such as isocyanide and CO to give the
corresponding complex [Cp*Rh(dppf-P,P%)(L)](PF6)2
(5b: L=XylNC; 5c: L=MesNC; 5d: TosCH2NC; 5e:
Complete atomic co-ordinates, thermal parameters,
bond lengths and angles, and a listing of observed and
calculated structure factors are available from Y. Ya-
mamoto on request.
L=(l)-3-(PhMeHCNHCO)C6H3NC;
5f:
L=CO)
(Scheme 1). The detailed structure was confirmed by
Acknowledgements
X-ray analysis of 5d (Fig. 3).
In the 31P{1H}-NMR spectra of 5 in CD3COCD3, the
chemical shift of the chelated ligand increased in the
One of the authors (J.-F. Ma) acknowledges the 60th
Anniversary Foundation of Toho University.

154
J.-F. Ma, Y. Yamamoto / Journal of Organometallic Chemistry 574 (1999) 148–154
[7] J.W. Kang, K. Moseley, M. Maitlis, J. Am. Chem. Soc. 91
References
(1969) 5971.
[8] J.J. Bishop, A. Davison, M.L. Katcher, D.W. Lichtenberg, R.E.
Merrill, J.C. Smart, J. Organomet. Chem. 27 (1971) 241.
[9] H.M. Walborsky, G.E. Niznik, J. Org. Chem. 37 (1972) 187.
[10] D.T. Cromer, J.T. Waber, International Tables for X-ray Crys-
tallography, vol. IV, Table 2.2A, The Kynoch Press, Birming-
ham, UK, 1974.
[11] J.A. Ibers, W.C. Hamilton, Acta Crystallogr. 17 (1964) 781.
[12] D.C. Creagh, W.J. McAuley, in: A.J.C. Wilson (ed.), Interna-
tional Tables for X-ray Crystallography, Vol. C, Table 4.2.6.8,
Kluwer, Boston, 1992, pp. 219–222.
[13] X.-H. Han, Y. Yamamoto, J. Organomet. Chem. in press.
[14] M. Sato, M. Asai, J. Organomet. Chem. 508 (1996) 121.
[15] E.T. Singewald, C.S. Slone, C.L. Stern, C.A. Mirkin, G.P.A.
Yap, L.M. Liable-Sands, A.L. Rheingold, J. Am. Chem. Soc.
119 (1997) 3048.
[1] (a) K.S. Gan, T.S.A. Hor, in: A. Togni, T. Hayashi (eds.),
Ferrocenes: Homogeneous Catalysis, Organic Synthesis, Mate-
rial Science, VCH, Whinheim, 1995, p. 1. (b) P.J. Stang, H.
Plenyuk, J. Fan, A.M. Arif, Organometallics 15 (1996) 904.
[2] (a) T. Ohe, N. Miyaura, A. Suzuki, J. Org. Chem. 58 (1993)
2201. (b) M. Sato, A. Miyaura, A. Suzuki, Chem. Lett. (1989)
1405. (c) W.J. Thompson, J. Gaudino, J. Org. Chem. 49 (1984)
5237.
[3] O.R. Hughe, J.D. Unruh, J. Mol. Catal. 12 (1981) 71.
[4] Y. Yamamoto, T. Tanase, I. Mori, Y. Nakamura, J. Chem. Soc.
Dalton Trans. (1994) 3191.
[5] F.-J. Ma, Y. Yamamoto, J. Organomet. Chem., in press.
[6] F.-J. Ma, Y. Yamamoto, J. Organomet. Chem. 545–546 (1997)
577.
.
.