The reaction of titanocene bis(ferrocenylacetylide) and bis(ruthenocenylacetylide) with silver cation: Formation of bis(Ti-tweezers) silver complexes

Article abstract of DOI:10.1016/S0022-328X(98)00785-2

Titanocene bis(acetylide) where the acetylide has ferrocenyl or ruthenocenyl terminal group (C₅H₄R)₂Ti{(CC)_n-Mc}₂, reacted with 0.5 equivalent amount of AgPF₆ giving cationic heptanuclear c

Full text of DOI:10.1016/S0022-328X(98)00785-2

Journal of Organometallic Chemistry 569 (1998) 169–175
The reaction of titanocene bis(ferrocenylacetylide) and
bis(ruthenocenylacetylide) with silver cation: formation of
bis(Ti-tweezers) silver complexes1
Yukiko Hayashi a, Masahisa Osawa a, Kimiko Kobayashi a, Takuma Sato a, Masaru Sato b,
Yasuo Wakatsuki a,*
a The Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-0198, Japan
b Chemical Analysis Center, Saitama Uni6ersity, Urawa, Saitama 338-8570, Japan
Received 4 April 1998
Abstract
Titanocene bis(acetylide) where the acetylide has ferrocenyl or ruthenocenyl terminal group (C5H4R)2Ti{(CꢀC)n-Mc}2, reacted
with 0.5 equivalent amount of AgPF6 giving cationic heptanuclear complexes of the form [(C5H4R)4Ti2{(CꢀC)n-Mc}4Ag](PF6) (1a:
R=SiMe3, n=1, Mc=ferrocenyl, 2a: R=H, n=2, Mc=ferrocenyl, 3a: R=SiMe3, n=2, Mc=ferrocenyl, 4a: R=SiMe3,
n=1, Mc=ruthenocenyl) in good yields. Likewise, complex [(C5H4SiMe3)4Ti2(CꢀCPh)4Ag](PF6) (5a) was isolated. The Ti(IV)–
Fe(II)–Ag(I) complex 3a was structurally characterized to confirm the solid-state geometry of the first bis(Ti-tweezers) type
chelate complex with silver cation in which the silver was coordinated by four triple bonds of the two titanocene bis(acetylide)
moieties. The similar Ti(IV)–Ru(II)–Ag(I) complex 4a was also characterized by single-crystal X-ray analysis. Complex 3a reacted
with 1.5 equivalents (with respect to Ti) of AgPF6 to liberate Fc–(CꢀC)4-Fc (Fc=ferrocenyl) quantitatively. © 1998 Elsevier
Science S.A. All rights reserved.
Keywords: Titanocene bis(acetylide); Ferrocenyl; Ti-tweezers
the silver salt had to be added carefully in small po-
tions. On monitoring the reaction by IR w(CꢀC) bands,
we noticed that addition of ca. 0.5 equivalents AgPF6
gave a new species which, on further addition of
AgPF6, liberates progressively the bis(ferrocenyl) car-
bon-rod as the final product. This intermediate species
turned out to be a bis(Ti-tweezers) type complex,
formed by aggregation of two starting titanocene
bis(acetylide) molecules on one silver cation as de-
scribed in detail in the present report.
1. Introduction
We reported recently the synthesis of titanocene bis(-
ferrocenylacetylide) and bis(ruthenocenylacetylide)
complexes [1,2]. The former complex showed unique
redox reactivity, i.e. on oxidation of the two terminal
ferrocenyl units by either electrochemical method or
silver salt, homolytic splitting of the Ti–C bonds and
subsequent coupling of the two acetylide units take
place to give ‘carbon rod’ with neutral ferrocenyl termi-
nal groups in 90–95% yield (Scheme 1). A quite similar
reaction was reported later by Lang et al. [3]. Since
addition of excess AgPF6 caused oxidation of the ferro-
cenyl unit of the product and retarded the yield of the
desired neutral bis(ferrocenyl) carbon-rod compound,
A
number of 1:1 complexes of bis(alkynyl)ti-
tanocenes with metal fragments [(C5H4R%)2Ti(Cꢀ
CR)2]M, have been reported [4–12]. Most of these
complexes (M=Ni(CO), Pt(PR3)2, FeCl2, Co(CO),
CuX, CuR, AuR, AgX) display the structure with an
embedded M unit between the ‘Ti(IV)-tweezers’ indicat-
ing ability of the bis(alkynyl)titanocene to stabilize a
variety of metal fragments via alkynyl ligand bridge. To
the best of our knowledge, however, bis(tweezers) type
* Corresponding author. Fax: +81 48 4624665.
1 Dedicated to Professor Nakamura on the occasion of his retire-
ment from Osaka University.
0022-328X/98/$19.00 © 1998 Elsevier Science S.A. All rights reserved.
PII S0022-328X(98)00785-2

170
Y. Hayashi et al. / Journal of Organometallic Chemistry 569 (1998) 169–175
Scheme 1.
2:1 complex of this family has not been reported. There
are two precedents though in diphosphineplatinum(II)
phenylacetylide chemistry, [Pt2(CꢀCPh)4(dppe)2Cu]+
and [Pt2(CꢀCPh)4(PPh3)4Ag]+ [13,14]. These platinum
complexes are stable, while the Ti(IV)–Fe(II)–Ag(I)
counterpart reported here is the prerequisite for the final
redox product. Furthermore, some of the complexes
reported here have diynyl arms with ferrocenyl end
groups: hence their molecular dimension is much larger
than those of the reported platinum complexes. Detailed
characterization of the new aggregates and its implication
for the silver cation-induced coupling of the two acetylide
units on Ti have been discussed in the present report.
consumed from the beginning was exactly 2 equivalents
with respect to starting complex 2. Apparently the
transformation shown in Scheme 1 is a two-stage reaction
and the first product appears to be relatively stable.
Isolation of this new product (2a) was indeed easily
carried out by simply adding 0.5 equivalents AgPF6 to a
CH2Cl2 solution of 2 and evaporating the solvent after 30
min. It was stable enough to undergo recrystallization. In
a similar fashion, three analogs 1a, 3a and 4a were
isolated in good yields as crystalline solid (Eq. (1)). The
FAB/MS, IR, NMR spectroscopy, and elemental analy-
sis indicated that these were 2:1 adducts of the titanocene
bis(acetylide) and AgPF6, of the general form
[(C5H4R)4Ti2{(CꢀC)n-Mc}4Ag](PF6) (Mc=ferrocenyl
or ruthenocenyl). These complexes are moderately stable
in solution at r.t. but decompose easily by illumination
from lamps so that their preparation and purification
have to be carried out in dark.
2. Results and discussion
2.1. Formation of the aggregates
The complexes 1a and 4a show the IR w(CꢀC) band at
2015 and 2020 cm−1, respectively, which are ca. 40 cm−1
lower energy than those of parent 1 (2056 cm−1) and 4
(2059 cm−1). The diyne complex 2a exhibits the bands at
2161 and 1988 cm−1, 3a at 2161 and 1987 cm−1 as
compared to the corresponding bands of the parent 2 at
2172 and 2021 cm−1, and 3 at 2171 and 2021 cm−1. The
lower energy band of the parent complexes, therefore,
shifted by ca. 30 cm−1 but the shift of the higher energy
band was only 10 cm−1. Apparently, silver ion is
interacting with one of the triple bonds of the diyne
moiety and this was further proved by X-ray structure
analysis of 3a (vide infra.). The structural characteriza-
tion of the Rc-ethynylene-Ti–Ag aggregate 4a (Rc=
ruthenocenyl) has also been carried out.
To a CH2Cl2 solution of the bis(ferrocenyldiynyl)ti-
tanocene complex (2), was added AgPF6 in CH2Cl2
slowly through a mechanically controlled syringe while
the reaction was monitored by IR w(CꢀC) peaks. As the
sharp peaks of the starting 2 (2171 and 2021 cm−1
)
decrease, new peaks grew up at 2161 and 1988 cm−1. At
the stage this change was completed, the amount of
AgPF6 added was ca. 0.5 equivalents with respect to the
moles of 2. The addition of the solution of AgPF6 was
continued which lead to the decrease of 2161 and 1988
peaks with concomitant growth of the peak at 2196 cm−1
of the final coupling product, Fc–(CꢀC)4–Fc. When this
second change was completed, the total amount of AgPF6

Y. Hayashi et al. / Journal of Organometallic Chemistry 569 (1998) 169–175
171
Fig. 1. Molecular structure of the cationic part of 3a with the atomic numbering scheme.
in 1–3, which is very susceptible to Ag+, the titanocene
bis(acetylide) catches the Ag cation in its tweezers at
the initial step of the reaction. Probably because anion
PF6− is too bulky to have strong direct interaction with
Ag+, the reaction does not form stable 1:1 Ti-tweezers-
AgPF6 type complex but proceeds further to form the
bis(Ti-tweezers)-Ag+ aggregate. The Ag+ trapped in
this aggregate, however, can participate in oxidation of
the ferrocenyl group at the second stage of the reaction:
When more Ag salt is added to the system, some of the
four ferrocenyl units of the bis(Ti-tweezers)-Ag+ aggre-
gate should be oxidized by the second Ag+ and cause
to decrease the electron density at the CꢀC triple bonds.
Dismissal of the aggregate and re-activation of the
initially captured Ag+ will then follow.
For comparison, a non-metallocenyl derivative of
titanocene acetylide, (C5H4SiMe3)2Ti(CꢀC–Ph)2 (5),
was treated with AgPF6 (0.5 equimolar relative to Ti) in
a similar manner to give again the bis(Ti-tweezers) type
complex [(C5H4SiMe3)4Ti2(CꢀC–Ph)4Ag](PF6) (5a).
In the Mo¨ssbauer spectra of 1a and 3a measured at
77 K, only a broad doublet was observed whose IS and
QS values were 0.53 and 2.28 mm s−1, respectively.
Their Mo¨ssbauer parameters are unchanged from those
of the parent complexes 1 and 3; IS=0.52–0.54 mm
s
−1, QS=2.28–2.31 mm s−1, which are typical values
for ferrocene derivatives. This indicates that the elec-
tronic status of the ferrocenyl group is that of Fe(II)
and has not changed before and after the adduct for-
mation with Ag+.
Although addition of 1.5 equivalents amount of
AgPF6 (relative to Ti) to 1a–3a lead to oxidation of the
ferrocenyl groups releasing the coupling product Fc–
(CꢀC)n–Fc in almost quantitative yields (Scheme 1), a
similar reaction of 4a was not feasible and resulted in
decomposition to uncharacterizable precipitate since
one-electron oxidation of ruthenocene is difficult [15].
In the case of 5a, addition of 0.5 equivalents AgPF6
2.2. X-ray structural analysis of 3a and 4a
Although crystallization of 3a in THF afforded good
crystals, their size was small. Only metal atoms could
be refined with anisotropic thermal parameters because
of the limited number of useful peak intensity data. The
ORTEP drawing of the cation part is shown in Fig. 1
and the selected structural parameters are listed in
Table 1.
lead to a new species having the w(CꢀC) at 2023 cm−1
,
which we assumed to be a 1:1 complex of 5 and AgPF6.
It was not crystalline and on standing its solution or on
addition of further AgPF6, it decomposed to intractable
material.
All of these observations imply the remarkably high
ability of the titanocene bis(acetylide) moiety to chelate
a metal unit: even when it has ferrocenyl end group as
The cationic framework has two (C5H4SiMe3)2-
Ti{(CꢀC)2–Fc)2 tweezers units which are oriented al-
most perpendicularly each other, the dihedral angle
Ti(1)–C(1)–C(S)/Ti(2)–C(9)–C(13) being 86(8)°. The
Ti(1)–Ag–Ti(2) is linear where Ti–Ag distances are
˚
3.26(1) and 3.19(1) A in comparison to the Ti–Ag

172
Y. Hayashi et al. / Journal of Organometallic Chemistry 569 (1998) 169–175
Table 1
Table 2
Selected bond lengths (A) and angles (°) for [(C5H4SiMe3)4-
Ti2(CꢀCCꢀCFc)4Ag](PF6)·THF (3a·THF)
˚
Selected bond lengths (A) and angles (°) for [(C5H4SiMe3)4-
Ti2(CꢀCRc)4Ag](PF6) (4a)
Ti(1)–C(1)
Ti(2)–C(9)
Ag–C(1)
Ag–C(9)
Ag–C(2)
Ag–C(10)
Ag–Ti(1)
2.10(4)
2.12(5)
2.40(4)
2.38(5)
2.68(4)
2.77(4)
3.26(1)
Ti(1)–C(5)
Ti(2)–C(13)
Ag–C(5)
Ag–C(13)
Ag–C(6)
2.07(4)
2.14(4)
2.38(4)
2.36(4)
2.66(5)
2.81(4)
3.19(1)
Ti(1)–C(41)
Ti(2)ꢁC(5)
AgꢁC(1)
AgꢁC(5)
AgꢁC(2)
AgꢁC(6)
C(1)ꢁC(2)
C(5)ꢁC(6)
AgꢁTi(1)
2.13(2)
2.12(2)
2.35(2)
2.37(1)
2.81(2)
2.78(1)
1.23(3)
1.24(3)
Ti(1)ꢁC(3)
Ti(2)ꢁC(7)
AgꢁC(3)
AgꢁC(7)
AgꢁC(4)
AgꢁC(8)
C(3)ꢁC(4)
C(7)ꢁC(8)
2.13(2)
2.11 (1)
2.40(1)
2.41(2)
2.77(1)
2.72(2)
1.23(3)
1.22(2)
3.267(3)
93.7(6)
Ag–C(14)
Ag–Ti(2)
C(1)–Ti(1)–C(5)
93.9(13)
C(9)–Ti(2)–C(13)
95.8(16)
3.248(3) AgꢁTi(2)
C(1)ꢁTi(1)ꢁC(3)
Ti(1)ꢁC(1)ꢁC(2)
Ti(2)ꢁC(5)ꢁC(6)
93.8(6)
165.3(12)
162.9(12)
C(5)ꢁTi(2)ꢁC(7)
Ti(1)ꢁC(3)ꢁC(4)
Ti(2)ꢁC(7)ꢁC(8)
172.7(13)
170.9(13)
˚
distance of 3.16(1) A in a related 1:1 Ti-bis(acetylide)-
Ag complex [(C5H4SiMe3)2Ti(CꢀC–SiMe3)2]AgNO2 (6)
[10]. The Ag atom is interacting with four CꢀC triple
bonds next to the two Ti atoms. Non-equivalent link-
ages of the Ag atom to C(h) and C(i) carbons of the
Ti-acetylide have been reported in 6, where Ag–C(h) is
metric structure while the Ag atom of the other
molecule is on the inversion center and therefore this
unit has symmetric structure. Since the overall struc-
tures of them are almost same, the ORTEP drawing
and the selected structural data of the cation part are
shown, in Fig. 2 and Table 2, only for the asymmetric
molecule.
The structural feature of 4a, whose Ag atom is
tetrahedrally coordinated by four acetylene fragments
with the dihedral angle Ti(1)–C(1)–C(3)/Ti(2)–C(5)–
C(7) of 86.0(1)°, is similar to that of 3a except the
shorter tweezers arms. Ti(1)–Ag–Ti(2) is again linear
˚
shorter (2.29(2), 2.33(2) A) and Ag–C(i) longer
(2.41(2), 2.43(2) A). This tendency is more pronounced
˚
˚
in 3a: Ag–C(h) 2.36(4)–2.40(4) A; Ag–C(i) 2.66(5)–
˚
2.81(4) A. Particularly the Ag–C(i) bonds are much
longer when compared to the corresponding values in 6
apparently owing to the steric reasons.
The Ti–Ru–Ag complex 4a crystallized in the mono-
clinic space group C2/c with one and a half independent
molecules. One of the molecules occupy a general posi-
tion in the unit cell and has crystallographically asym-
˚
with Ti–Ag distances of 3.267(3) and 3.248(3) A. All
four Ag–C(i) bonds (2.72(2)–2.81(2) A) are longer
˚
Fig. 2. Molecular structure of the cationic part of 4a with the atomic numbering scheme.

Y. Hayashi et al. / Journal of Organometallic Chemistry 569 (1998) 169–175
173
Fig. 3. View along the Ti–Ag–Ti axis. (a) Cationic part of 3a; (b) cationic part of 4a.
˚
All manipulations were performed under argon. In
addition, all reactions of AgPF6 were carried out in a
flask covered with aluminum foil to shield it from the
light. Solvents were purified and distilled prior to use.
than in 6 by as much as 0.3–0.4 A. This is brought
about partly by longer Ti–Ag distances and partly by
larger bend at C(1) and C(5) in 4a (165(1) and 163(1)°)
than the corresponding bend at C(h)’s of 6 (171(2) and
170(2)°).
3.1. Synthesis of [(C5H4R)4Ti2{(CꢀC)n-Mc}4Ag](PF6)
3.1.1. [(C5H5)4Ti2(CꢀCCꢀC–FC)4Ag](PF6) (2a)
When viewed along the axis Ti–Ag–Ti as shown in
Fig. 3, it is apparent that the carbon rods are curved in
a S-shaped way. This tendency is attributed to the steric
repulsion between the large metallocenyl end groups at
the rod-terminal with the cyclopentadienyl rings of
titanocene of the aggregating partner. The shortest
interatomic distance found in metallocenyl Cp car-
To
a
CH2Cl2
solution
(80
ml)
of
(C5H5)2Ti(CꢀCCꢀC–Fc)2 (2) (103 mg, 0.16 mmol) was
added dropwise AgPF6 (20 mg, 0.08 mmol) in CH2Cl2
(40 ml) at r.t. The reaction mixture was stirred for 30
min; it turned gradually from moss-green to light-green.
After the solvent was evaporated, the residue was re-
crystallized from CH2Cl2/hexane at −30°C to give 2a
as deep green needles: yield 105 mg (85%). Anal. Calcd
for C76H56AgF6Fe4PSi4Ti2 ·1/2CH2Cl2: C, 58.02; H,
3.63; Ag, 7.00. Found: C, 57.83; H, 4.25; Ag, 6.81%.
The presence of 1/2·CH2Cl2 was also confirmed by
1H-NMR measurement in acetone-d6. 1H-NMR
(CD2Cl2) l 6.51 (s, 20H, C5H5–Ti), 4.55 (bs, 8H,
C5H4–Fe), 4.40 (bs, 8H, C5H4–Fe), 4.28 (s, 20H,
C5H5–Fe). IR (CH2Cl2) w(CꢀC) 2161, 1988 cm−1. MS
(FAB+) m/z 1395 [M-(PF6)]+.
˚
bon—titanocene Cp carbon is 3.22 A in both 3a and
4a.
3. Experimental section
1H- and 13C-NMR spectra were measured on a JEOL
JNM-EX270 spectrometer. IR spectra were recorded on
a Perkin-Elmer 1600 FT-IR spectrometer. Mass spectra
(FAB+) were obtained on a J1EOL JMS-HX110 mass
spectrometer. Mo¨ssbauer spectra were measured with a
constant-acceleration type spectrometer, and the veloc-
ity scale was calibrated on the spectrum of metallic iron
at room temperature. Spectra were fitted with
Lorentzian line shapes by least squares. The isomer
shifts were reported with respect to h-Fe foil at room
Complexes 1a, 3a and 4a were prepared in a similar
manner.
3.1.2. [(C5H4SiMe3)4Ti2(CꢀC–Fc)4Ag](PF6) (1a)
Yield 87%; blue-green needles. Anal. Calcd for
C80H88AgF6Fe4PSi4Ti2: C, 55.42; H, 5.12; Ag, 6.22.
Found: C, 55.21; H, 5.11; Ag, 6.30%. 1H-NMR
(CD2Cl2) l 6.19 (t, J=2.3 Hz, 8H, C5H4–Ti), 6.04 (t,
J=2.3 Hz, 8H, C5H4–Ti), 4.68 (t, J=1.8 Hz, 8H,
temperature.
The
titanocene
derivatives
(C5H4R)2Ti{(CꢀC)n-Mc}2 (1–4) were prepared as re-
ported previously [1] and (C5H4SiMe3)2Ti(CꢀCPh)2 (5)
[16] were prepared by the literature method.

174
Y. Hayashi et al. / Journal of Organometallic Chemistry 569 (1998) 169–175
Found: C, 49.94; H, 4.61; Ag, 5.57%. 1H-NMR
(CD2Cl2) l 6.29 (t, J=2.3 Hz, 8H, C5H4–Ti), 6.19 (t,
J=2.3 Hz, 8H, C5H4–Ti), 5.00 (t, J=1.6 Hz, 8H,
C5H4–Ru), 4.79 (t, J=1.6 Hz, 8H, C5H4–Ru), 4.68 (s,
20H, C5H5–Ru), 0.26 (s, 36H, TMS). IR (CH2Cl2)
w(CꢀC) 2020 cm−1. MS (FAB+) m/z 1770 [M-(PF6)]+.
C5H4–Fe), 4.57 (t, J=1.8 Hz, 8H, C5H4–Fe), 4.34 (s,
20H, C5H5–Fe), 0.30 (s, 36H, TMS). IR (CH2Cl2)
w(CꢀC) 2015 cm−1. MS(FAB+) m/z 1589 [M-(PF6)]+.
Mo¨ssbauer parameters IS=0.53, QS=2.28 mm s−1
.
3.1.3. [(C5H4SiMe3)4Ti2(CꢀCCꢀC–Fc)4Ag](PF6) (3a)
Yield 92%; deep green needles. Anal. Calcd for
C88H88AgF6Fe4PSi4Ti2: C, 57.76; H, 4.85; Ag, 5.89.
Found: C, 57.71; H, 4.82; Ag, 5.71%. 1H-NMR
(CD2Cl2) l 6.81 (t, J=2.3 Hz, 8H, C5H4–Ti), 6.59 (t,
J=2.3 Hz, 8H, C5H4Ti), 4.54 (t, J=1.8 Hz, 8H,
C5H4–Fe), 4.40 (t, J=1.8 Hz, 8H, C5H4–Fe), 4.26 (s,
20H, C5H5–Fe), 0.31 (s, 36H, TMS). IR (CH2Cl2)
w(CꢀC) 2161, 1987 cm−1. MS (FAB+) m/z 1685
[M(PF6)]+. Mo¨ssbauer parameters IS=0.53, QS=
3.2. Synthesis of [(C5H4SiMe3)4Ti2(CꢀCPh)4Ag](PF6)
(5a)
To a solution of (C5H4SiMe3)2Ti(CꢀCPh)2 (5) (84
mg, 0.16 mmol) in THF (80 ml) was added dropwise
AgPF6 (20 mg, 0.08 mmol) in THF (27 ml) at r.t. The
reaction mixture was stirred for 30 min during which
time the color turned gradually from orange to red-or-
ange. After the solvent was evaporated, the residue was
recrystallized from THF/hexane at −30°C to give 5a
as red-orange needles: yield 88 mg (85%). Anal. Calcd
for C64H72AgF6PSi4Ti2: C, 59.03; H, 5.57; Ag, 8.28.
Found: C, 58.88; H, 5.69; Ag, 8.21%. 1H-NMR
(CD2Cl2) l 7.70–7.49 (m, 20H, Ph), 6.24 (t, J=2.3 Hz,
8H, C5H4–Ti), 6.03 (t, J=2.3 Hz, 8H, C5H4–Ti), 0.08
(s, 36H, Me). IR (THF) w(CꢀC) 2039 cm−1. MS
(FAB+) m/z 1157 [M-(PF6)]+.
2.28 mm s−1
.
3.1.4. [(C5H4SiMe3)4Ti2(CꢀC–Rc)4Ag](PF6) (4a)
Yield 99%; red-purple crystals. Anal. Calcd for
C80H88AgF6PRu4Si4Ti2: C, 50.18; H, 4.63; Ag, 5.63.
Table 3
The crystal data of complexes 3a·THF and 4a
3a·THF
4a
Formula
C88H88AgFe4Si4T C80H88AgRu4Si4T
3.3. X-ray crystal analysis
i2 ·PF6 ·C4H8O
1902.14
i2 ·PF6
1914.84
Molecular weight
Crystal size (mm)
Crystal system
A deep green crystal of 3a grown in THF at 5°C was
mounted in a glass capillary with a small volume of
mother liquor. The X-ray measurements were per-
formed on a Mac Science MXC18 diffractometer with
graphite-monochromated Mo–Kh radiation (u=0.7107
0.35×0.20×0.07 1.40×1.00×0.25
Triclinic
Monoclinic
(
Space group
P1
C2/c
Unit cell dimensions
˚
a (A)
16.692(8)
17.105(3)
18.054(2)
75.67(1)
87.42(2)
87.60(2)
4987
38.13(7)
24.284(7)
28.09(5)
90
105.36(2)
90
˚
b (A)
˚
A) at r.t. in the dark.
˚
c (A)
Deep purple crystals of 4a were grown in CH2Cl2/
hexane at r.t. Oscillation and nonscreen Weissenberg
photographs were recorded on the imaging plates on
Mac Science DIP3000 with an 18-kW rotating anode
generator. Data reduction and determination of cell
parameters were made by MAC DENZO program
system.
The structures were solved by direct methods using
SIR92 in the CRYSTAN-GM program system (soft-
ware package for structure determination) and refined
by full-matrix least-squares procedures. Hydrogen
atoms were not located. The crystallographic and refin-
ement parameters are summarized in Table 3.
h (°)
i(°)
k (°)
3
˚
V (A )
25080
12
Z
2
Dcalcd (Mg m−3
)
1.267
1.521
v (mm−1
)
10.163
298
15.739
298
Temperature (K)
Radiation
Mo–Kh (u=
0.71073)
23.86
Mo–Kh (u=
0.71073)
28.83
qmax (°)
h, k, l ranges
−19 0, −20 20, 0 53, 0 34, −34
−21 21
18 322
12 139
34
24 853
21 329
No. of reflections
No. of independent reflec-
tions
No. of reflections in ref. [I] 3461
3|(I)]
12 969
No. of atoms and parame-
ters
207, 480
186, 1326
References
Final R
Final Rw
Goodness of Fit
Max/min in diff. map (e A
0.094
0.116
3.11
1.91/−3.54
0.076
0.092
3.63
2.57/−1.67
[1] Y. Hayashi, M. Osawa, Y. Wakatsuki, J. Organomet. Chem. 542
(1997) 241.
[2] Y. Hayashi, M. Osawa, K. Kobayashi, Y. Wakatsuki, Chem.
Commun. (1996) 1617.
−
˚
3)
[3] S. Back, H. Pritzkow, H. Lang, Organometallics 17 (1998) 41.

Y. Hayashi et al. / Journal of Organometallic Chemistry 569 (1998) 169–175
175
[4] J.R. Berenguer, L.R. Falvello, J. Fornies, E. Lalinde, M. Tomas,
Organometallics 12 (1993) 6.
[11] H. Lang, K. Kohler, B. Schiemenz, J. Organomet. Chem. 495
(1995) 135.
[5] M.D. Janssen, M. Herres, L. Zsolnai, D.M. Grove, A.L. Spek,
H. Lang, G.V. Koten, Organometallics 14 (1995) 1098.
[6] M.D. Janssen, M. Herres, A.L. Spek, D.M. Grove, H. Lang,
G.V. Koten, J. Chem. Soc. Chem. Commun. (1995) 925.
[7] H. Lang, L. Zsolnai, J. Organomet. Chem. 406 (1991) 5.
[8] H. Lang, M. Herres, L. Zsolnai, W. Imhof, J. Organomet.
Chem. 409 (1991) 7.
[12] H. Lang, K. Kohler, L. Zsolnai, Chem. Commun. (1996) 2043.
[13] S. Yamazaki, A. J. Deeming, J. Chem. Soc. Dalton Trans. (1993)
3051.
[14] I. Ara, J.R. Berenguer, J. Fornies, E. Lalinde, M.T. Moreno, J.
Organomet. Chem. 510 (1996) 63.
[15] M.G. Hill, W.M. Lamanna, K.R. Mann, Inorg. Chem. 30 (1991)
4687.
[9] H. Lang, W. Imhof, Chem. Ber. 125 (1992) 1307.
[10] H. Lang, M. Herres, L. Zsolnai, Organometallics 12 (1993) 5008.
[16] J.H. Teuben, H.J.D. L. Meijer, J. Organomet. Chem. 17 (1969)
87.
.