The reactivity of TMSN3 with ruthenium cyclopropenyl complexes containing different ligands and different substituent at Cγ

Article abstract of DOI:10.1016/j.jorganchem.2010.12.017

Ruthenium vinylidene complexes 2a-2c containing indenyl and bidentate dppe ligands can be obtained in efficient yields. Treatment of the cationic ruthenium vinylidene complexes with n-Bu₄NOH in acetone yields the neutral cyclopropenyl products (η⁵-C₉H₇)(dppe)Ru- CC(Ph)CHR (3) (3a, R = Ph; 3b, R = CN; 3c, R = p-C₆H₄-CN) via the deprotonation reaction. Reaction of complexes 3a and 3c with Me ₃SiN₃ (TMSN₃) the N-coordinated complexes 4a and 4c can be obtained as stable products. Complex 3b containing CN group at Cγ in the cyclopropenyl ring reacts with TMSN₃ yielded the tetrazolate complex 5b. Similar cyclopropenyl products containing indenyl and two triphenylphosphine ligands 3′ can also be synthesized. Reaction of complex 3b′ with TMSN₃ also yielded the tetrazolate complex as the major product. And the minor products are [Ru]-N₃ and organic compound 6b. Reaction of 3a′ and 3c′ with TMSN₃ yielded [Ru]-N₃. The corresponding organic products can also be obtained via the N₃^- attacking the metal center in the N-coordinated complexes 4a′ and 4c′.

Full text of DOI:10.1016/j.jorganchem.2010.12.017

Journal of Organometallic Chemistry 696 (2011) 1280e1288
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
The reactivity of TMSN3 with ruthenium cyclopropenyl complexes containing
different ligands and different substituent at C
g
,
b
Hui-Ling Sung a , Hsiu-Ling Hsu
*
a Department of Mathematics and Science (Pre-college), National Taiwan Normal University, Linkou, Taiwan, ROC
b Department of Chemical and Materials Engineering, Lunghwa University of Science and Technology, Taoyuan, Taiwan, ROC
a r t i c l e i n f o
a b s t r a c t
Article history:
Ruthenium vinylidene complexes 2ae2c containing indenyl and bidentate dppe ligands can be obtained
in efficient yields. Treatment of the cationic ruthenium vinylidene complexes with n-Bu4NOH in acetone
Received 30 September 2010
Received in revised form
8 December 2010
yields the neutral cyclopropenyl products (
h
5-C9H7)(dppe)RueC]C(Ph)CHR (3) (3a, R ¼ Ph; 3b, R ¼ CN;
3c, R ¼ p-C6H4eCN) via the deprotonation reaction. Reaction of complexes 3a and 3c with Me3SiN3
Accepted 10 December 2010
(TMSN3) the N-coordinated complexes 4a and 4c can be obtained as stable products. Complex 3b con-
taining CN group at Cg in the cyclopropenyl ring reacts with TMSN3 yielded the tetrazolate complex 5b.
Keywords:
Ruthenium
Vinylidene
Cyclopropenyl
N-Coordinated
Tetrazolate
Similar cyclopropenyl products containing indenyl and two triphenylphosphine ligands 30 can also be
synthesized. Reaction of complex 3b0 with TMSN3 also yielded the tetrazolate complex as the major
product. And the minor products are [Ru]eN3 and organic compound 6b. Reaction of 3a0 and 3c0 with
TMSN3 yielded [Ru]eN3. The corresponding organic products can also be obtained via the Nꢀ3 attacking
the metal center in the N-coordinated complexes 4a0 and 4c0.
Ó 2010 Elsevier B.V. All rights reserved.
1. Introduction
Cyclopropene is known to dimerize and polymerize at room
temperature [26,27]. Substituted cyclopropenes are generally more
The organometallic chemistry of transition-metal vinylidene
complexes has attracted a great deal of attention in recent years [1,2].
These complexes also play an important role as strategic interme-
diates [3e5]. The importance of vinylidene intermediates in catalytic
conversions such as asymmetric hydrogenation [6e9], cyclization of
conjugated enediynes [10,11] and olefin metathesis [12e14] and
polymerization [15,16] has been suggested [17,18].
Extensive reviews on this subject exist. The optimal entry into the
transition-metal vinylidene complexes is the addition of electro-
philes to the electron-rich carbon of metal alkynyl complexes [19,20].
A theoretical study of vinylidene complexes indicated localization of
stable. They dimerize at higher temperatures [28,29]. Organic
cyclopropene is highly strained and plays a crucial role in organic
synthesis [30,31]. However, the cyclopropenyl ligand can be stabi-
lized by coordination with a transition metal through back-bonding
from the metal d-orbital to Ca. Synthesis of metal cyclopropenyl
derivatives in which the metal bonds to C(sp3) of the cyclopropenyl
ring has been reported in literature [32]. However, based on the
research of the study, only few of such a derivative in which the
metal is bonded to the C(sp2) of the three-membered ring have been
reported [33]. A few structurally different transition metal cyclo-
propenylidene complexes have been reported. Reaction of the metal
anionic silyl complex with organic 3,3-dichlorocyclopropenes in
THF at room temperature results in the anticipated carbene
complexes. The carbene complexes of this type are stabilized due to
electron withdrawal from the cyclopropene complex [34]. In
another case, metal cyclopropenyl complex that has the metal
bonding to C(sp3) of the cyclopropenyl ring undergoes a cyclo-
propenyl migration reaction to CO, yielding the 2-cyclopropene-1-
carbonyl complex [35].
electron density on Cb and the electron deficiency at Ca [21]. The
formation of metal vinylidene complexes has been used to promote
new carbonecarbon bond formation by the addition of carbon center
to the electrophilic carbon atom.
The vinylidene complexes of iron with dppe ligand have been
obtained [22e24]. The acidity of the aliphatic protons on a coordi-
nated dppe ligand in a cationic iron vinylidene complex [25] has
been employed for inducing the intramolecular cyclization between
the dppe and vinylidene ligand.
Ruthenium cyclopropenyl complexes by deprotonation reaction
of ruthenium vinylidene complexes have been reported in literature
[36e38]. In the ruthenium system, vinylidene and cyclopropenyl
complexes display distinctive reactivity [39,40]. To explore potential
applications of such a new type of complex, this study conducted
* Corresponding author. Tel.: þ886 2 77148390; fax: þ886 2 26022617.
E-mail address: hlsung@ntnu.edu.tw (H.-L. Sung).
0022-328X/$ e see front matter Ó 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2010.12.017

H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
1281
reactions of cyclopropenyl complexes with various organic
substrates.
Trimethylsilyl azide and sodiumazidewereusedwidelyinorganic
or organometallic reactions [41e43]. Coupling reaction of azide, such
as TMSN3, with simple alkyne and allyl carbonates catalyzed by Pd0/
CuI has been reported [44e47]. The azide reagent is also commonly
used in the synthesis of metal complexes with N-heterocyclic ligand.
The N-coordinated tetrazole derivatives have been obtained by the
reaction of sodium azide with the coordinated CN of the N-coordi-
nated iron nitrile complex [48]. The reaction of TMSN3 with a number
of ruthenium cyclopropenyl complexes containing different substit-
uents at the cyclopropenyl ring yielded various products. Herein we
report the synthesis of ruthenium cyclopropenyl complexes con-
taining indenyl and dppe, or PPh3 ligands. Then we report the reac-
tions of the cyclopropenyl complexes with TMSN3.
Fig. 1. Molecular structure of complex 2a (hydrogen atoms and phenyl groups on dppe
except the ipso carbon are removed for clarity). Thermal ellipsoids are shown at the
30% level. Selected bond lengths [Å] and angles [deg]: Ru(1)eP(1), 2.3359(13); Ru(1)eP
(2), 2.3067(11); Ru(1)eC(36), 1.829(4); C(36)eC(37), 1.328(6); C(37)eC(45), 1.514(7); P
(1)eRu(1)eP(2), 82.86(4); Ru(1)eC(36)eC(37), 176.5(4); C(36)eC(37)eC(45), 119.3(4);
C(37)eC(45)eC(46), 114.8(4).
2. Results and discussion
2.1. Preparation of cationic ruthenium vinylidene complexes
Indenylruthenium acetylide complex 1 [Ru(
C^CPh)] was prepared by the reaction of [RuCl(
with phenylacetylene in the presence of alcoholic CH3ONa [49].
Treatment of [Ru]eC^CePh (1, [Ru]](
5-C9H7)(dppe)Ru) with
h
5-C9H7)(dppe)(h1
5-C9H7)(dppe)]
-
h
study of 2b. The Ru(1)eC(36) bond length of 1.820(4) Å was in the
range of a regular rutheniumecarbon double bond in other crys-
tallographically characterized ruthenium vinylidene complexes.
The C(36)eC(37) bond length of 1.330(5) Å was a typical double
bond. The bond angles C(37)eC(36)eRu(1) and C(36)eC(37)eC(44)
were 176.5(3)ꢁ and 117.8(3)ꢁ, respectively.
h
organic halides such as benzyl bromide at room temperature fur-
nished cationic vinylidene complex 2a in 79% yield (Scheme 1). The
31P NMR spectra of 2a exhibited a singlet at
d
76.1, indicating the
chemical equivalence of the two phosphorus atoms. On the 13C{1H}
NMR spectrum, the RueC resonance appeared at 352.2 as
a triplet with a CeP coupling constant of 17.0 Hz.
a
d
2.2. Synthesis of the cyclopropenylruthenium complex 3a
Complex 2a was air-stable at room temperature. The molecular
structure was confirmed unequivocally by X-ray analysis. The
ORTEP drawing of 2a with thermal ellipsoids is shown at the 30%
probability level in Fig. 1. The Ru(1)eC(36) bond length of 1.829
(4) Å was in the range of a regular rutheniumecarbon double bond
in other crystallographically characterized ruthenium vinylidene
complexes [52,53]. The C(36)eC(37) bond length of 1.328(6) Å was
a typical double bond. The bond angles C(37)eC(36)eRu(1) and C
(36)eC(37)eC(45) were 176.5(4)ꢁ and 119.3(4)ꢁ, respectively.
Similarly, various vinylidene complexes [[Ru]]C]C(Ph)CH2R]þ
2b and 2c (2b, R ¼ CN, 2c, R ¼ p-C6H4eCN) were prepared using the
synthesis method for 2a. The indenylruthenium vinylidene
complexes 2a, 2b and 2c containing dppe ligand and various
Deprotonation of the vinylidene complex 2a by n-Bu4NOH in
acetone induces the intramolecular cyclization reaction and yielded
a neutral cyclopropenyl complex 3a (Scheme 1). The reaction
produces a yellow crystalline product in analytically pure form. Use
of acetone or acetonitrile as a solvent gives a good yield, and use of
other bases such as DBU (1,8-diazabicyclo[5,4,0] undec-7-ene) give
3a in comparable yield. The 31P NMR spectrum of 3a displays two
doublet resonances at
d 92.6 and 90.2 of an AX pattern with
JPeP ¼ 23.3 Hz due to the presence of a stereogenic carbon center at
the three-membered ring. On the 1H NMR spectrum of 3a, the
methyne (methine) proton appears at
NMR spectrum, the triplet at
124.1 with JCeP ¼ 9.5 Hz is assigned
to C
d
1.37, and on the 13C{1H}
d
substituents at C
g
were obtained as air-stable pink solids with
a.
71e86% yields. All indenylruthenium vinylidene complexes can be
obtained at room temperature and gave analytically pure complexes.
These complexes displayed a characteristic pink color in the solid
state. These complexes were characterized by NMR spectroscopy.
The synthesis and chemical reactivity of several neutral ruthe-
nium cyclopropenyl triphenylphosphine complexes in which the
metal bonds to one sp2 carbon atom of the three-membered cyclo-
propenyl ring have been reported [54]. Ruthenium cyclopropenyl
complex containing pentamethylcyclopentadiethyl (Cp*) and dppp
ligands was also be synthesized [40]. These cyclopropenylruthenium
complexes could be prepared from deprotonation reaction of their
vinylidene precursor. In the iron vinylidene complexes containing Cp
and dppe ligands, the relatively more acidic proton of the dppe
ligand in the cationic iron vinylidene complex could direct the
reaction to proceed via a different route. The metallacyclic iron
complex was obtained [55].
The characteristic deshielded Ca
resonances in the 13C NMR in the
region of
d
¼ 348 ꢂ 5. On the 1H NMR spectrum, the singlet reso-
nances for the CH2 group at Cb
appeared at 2.4e2.9 ppm. The 31P
NMR resonance appears as a singlet at
temperature due to the fluxional behavior of the vinylidene ligand
[50,51].
d
¼ 75.5 ꢂ 1 in CDCl3 at room
The structure of 2b was also confirmed by an X-ray diffraction
study. Fig. 2 shows the results of a single-crystal X-ray diffraction
Br
Ph
Ph
PhCH2Br
base
acetone
Ru
C C Ph
Ru
Ru
C
C
H
Ph2P
Ph2P
Ph2P
PPh2
PPh2
PPh2
Ph
Ph
1
2a
3a
Scheme 1.

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H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
electrophilic addition of a second TMS group at Cb followed by loss of
N2 is accompanied by metal migration and hydrolysis of the TMS
group to give the N-coordinated nitrile complex 4a. Trace of water in
the reaction solvent THF is believed to act as the source of the protons
that are incorporated into the product through hydrolysis of the TMS
group derived from the addition of TMSN3 to the three-membered
ring [38,58]. Intermediate complex 2aeN3 is unstable in solution at
room temperature and undergoes a further reaction with azide to
give 4a with azide counter anion as stable product. Conversion of
a vinylidene precursor to N-coordinated nitrile by hydrazine, an
organometallic Beckmann rearrangement, has been reported in an
iron system [59]. It has been reported that the similar product N-
coordinated ruthenium complex containing Nꢀ3 counter anion is
unstable. Exchange of the Nꢀ3 with PFꢀ6 made the N-coordinated
complex more stable [37,38].
2.4. Reaction of 3b with TMSN3
To compare with stereo effect of the cyclopropenyl complexes in
the reaction with TMSN3, we change the substituent at the sp3
carbon of the cyclopropenyl ring. The vinylidene complex 2b con-
Fig. 2. Molecular structure of complex 2b (hydrogen atoms and phenyl groups on dppe
except the ipso carbon are removed for clarity). Thermal ellipsoids are shown at the
30% level. Selected bond lengths [Å] and angles [deg]: Ru(1)eP(1), 2.3113(9); Ru(1)eP
(2), 2.3360(9); Ru(1)eC(36), 1.820(4); C(36)eC(37), 1.330(5); C(37)eC(44), 1.536(5); C
(44)eC(45), 1.453(7); C(45)eN(1), 1.134(6); P(1)eRu(1)eP(2), 82.04(3); Ru(1)eC(36)eC
(37), 176.5(3); C(36)eC(37)eC(44), 117.8(3); C(37)eC(44)eC(45), 111.0(3).
taining CN group at C
g can be obtained with a good yield. The
acetone solution of 2b added base at room temperature yielded
deprotonation product cyclopropenyl complex 3b.
Treatment of cyclopropenylruthenium complex 3b containing
2.3. Reaction of 3a with TMSN3
CN substituent at Cg with TMSN3 at room temperature for 4 h
afford the yellow tetrazolate complex 5b in 81% yield (Scheme 3).
Treatment of cyclopropenylruthenium complex 3a containing
The 31P NMR spectrum of 5b shows two doublet resonances at
phenyl substituent at C
g
with TMSN3 affords the N-coordinated
d
93.3 and 85.6 with JPeP ¼ 27.7 Hz due to the presence of an
asymmetric carbon center in the five-membered ring. On the 1H
NMR spectrum of 5b, a triplet resonance at
3.76 (JHeH ¼ 7.16 Hz)
is assigned to the methyne proton and two resonances displaying
doublets of an AB pattern at
2.10 (JHeH ¼ 16.7, 5.3 Hz) and 1.95
complex 4a with a 65% yield. The reaction conducted at room
temperature for 4 h, longer reaction time even in 8 h complex 4a is
still stable. A series of successive color changes were noted during the
course of the reaction: the light yellow solution of 3a first turned
orange upon addition of TMSN3 at room temperature, and then,
subsequently seen to turn yellow after 4 h elapsed. Complex 4a is
isolated asthefinal product, and isstableinair while inthe solid state.
Complex 4a is soluble in CH2Cl2, MeOH, and THF, but insoluble in
diethyl ether and hexane. The 31P NMR spectrum of 4a displays two
d
d
(JHeH ¼ 16.7, 9.0 Hz) are assigned to the diastereotopic methylene
group. The parent peak in the ESI mass spectrum of 5b clearly
indicates that 5b results from N3 group to the intermediate
complex 4b. By monitoring the reaction using 31P NMR spectros-
copy, the mixture of complexes 4b and 5b can be observed at the
initial stage of the reaction which is converted to complex 5b in THF
within 4 h at room temperature. Complex 5b is stable at room
temperature, soluble in THF, acetone but insoluble in ether and
hexane.
Complex 3b is stable in air and soluble in CH2Cl2 and THF but
insoluble in CH3CN and ether. Single crystals of 3b were obtained by
slow evaporation of the acetone/diethyl ether solution of 3b at
room temperature. The solid-state structure of 3b is determined by
an X-ray diffraction analysis. An ORTEP drawing of 3b is shown in
Fig. 3. The Ru(1)eC(36) bond length of 2.028(2) Å is typical for
doublet resonances at
the presence of a stereogenic center in the N-coordinated nitrile
ligand.
d
83.3 and 81.4 with JPeP ¼ 27.3 Hz indicating
The addition of TMSN3 to cyclopropenyl complex 3a leading to 4a
may proceed via the following pathway (Scheme 2). An electrophilic
addition of a TMS group to the sp3 carbon at the three-membered
ring with concomitant opening of the ring followed by hydrolysis of
the added TMS group affords vinylidene intermediate 2aeN3 con-
taining an azide anion. This is followed by nucleophilic addition of an
azide anion at C
a
of the vinylidene ligand [56,57]. Subsequent
N3
Ph
N3
C
N3
Ph
Ph
TMSN3
[Ru]
[Ru]
C
[Ru]
C
C
H
THF
Ph
Ph
3a
Ph
2a-N3
Ru
[Ru]=
Ph2P
PPh2
N3
N3
N2
N
N
N3
N
C
Ph
H
Ph
N
C
Ph
TMS hydrolysis
[Ru]
N
C
C
[Ru]
CH
Ph
[Ru]
C
TMS
Ph
Ph
4a
Scheme 2.

H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
1283
N3
Ph
N
N
Ph
TMSN3
Ph
N
Ru
Ru
Ru
N
C
C
H
H
N
Ph2P
Ph2P
Ph2P
PPh2
PPh2
PPh2
NC
NC
NC
3b
4b
5b
Scheme 3.
a RueC single bond and the C(36)eC(39) bond length of 1.301(3) Å
is a double bond, indicating coordination of the sp2 carbon of the
cyclopropenyl ligand. The bond angles Ru(1)eC(36)eC(39) and C
(36)eC(39)eC(40) of 161.46(19)ꢁand 157.5(2)ꢁ, respectively, are
both far larger than that of an idealized sp2 hybridization. The C
(36)eC(37) and C(37)eC(39) bond lengths of 1.584(3) and 1.495
(3) Å, respectively, are significantly different, consistent with the
favorable cleavage of the C(36)eC(37) bond. Other relevant crystal
data for complexes 2a, 2b, and 3b are also given in Table 1.
In the reaction of 3b with TMSN3, the reaction may proceed
similarly in the first stage to give an analog of 4b. Formation of 5b is
then rationalized by a [3 þ 2] cycloaddition of the C^N bond with
another azide anion followed by metal migration (linkage isomer-
ization) [60,61]. In some cases, the [3 þ 2] cyclization reaction was
occurred in an imine compound with an azide group. It has been
reported tetrazole compound resulting from an attack of an azide to
an imine compound with an appropriate leaving group following
cyclization [62]. Unlike the reactivity of 3a with TMSN3 yield the
stable N-coordinated product, the C^N bond coordinated with the
metal center by N atom in the 4b followed reaction with Nꢀ3 to
obtain the tetrazolate product 5b. The terminal CN group of
complex 3b is smaller than complex 3a to enhance the Nꢀ3 group
addition.
tetrazole-containing biologically active compounds are known in
literature [63e65]. Organic tetrazoles are generally prepared
starting from nitriles and NaN3 or TMSN3 and stoichiometric of
catalyst in the solvent [66e68]. Literature has reported that nitrile
groups react with azide creating a tetrazolate ring via [3 þ 2]
cycloaddition reaction [69].
2.5. Reaction of 3c with TMSN3
In the vinylidene complex, changing the CN group at Cg to the p-
C6H4eCN containing the CN group at the para position in the
phenyl ring, complex 2c can be obtained. Deprotonation reaction of
complex 2c yielded the cyclopropenyl complex 3c in 86% yield.
Reaction of complex 3c with TMSN3 yielded N-coordinated
complex 4c as the stable product in air in the solid state. Complex
4c can be obtained by a similar pathway of complex 4a (Scheme 4).
No tetrazolate complex was obtained even in the long reaction
time. On the 31P NMR spectrum of 4c, two doublet resonances at
d
83.9 and 81.2 with JPeP ¼ 27.1 Hz indicated the presence of
a diastereotopic center in the ruthenium N-coordinated complex.
On the 1H NMR spectrum, a triplet pattern at
4.37 with
d
JHeH ¼ 7.40 Hz was assigned to the proton at the diastereotopic
center.
Organic tetrazoles are increasingly important heterocyclic
compounds in medicinal chemistry. An enormous number of
The cyclopropenyl complexes containing indenyl and dppe
ligands can be obtained in good yield. N-coordinated complexes 4a
and 4c containing phenyl group and its derivatives at Cg and the
counter ion Nꢀ3 are very stable in air while in the solid state.
Complexes 4a and 4c would not undergo further nucleophilic
addition or cyclization is interpreted in terms of relatively larger
steric hindrance of a phenyl group relative to a CN group.
Table 1
Crystal data and refinement parameters for complexes 2a, 2b, and 3b.
a
2a$CH2Cl2
2b
3b
Empirical formula
Temperature
Crystal system
Space group
a, Å
C
51H45BrCl2P2Ru
C45H38INP2Ru
200(2) K
Monoclinic
C 2/c
37.7342(5)
10.75430(10)
18.5556(3)
90
93.7030(10)
90
7514.23(17)
8
C45H37NP2Ru
200(2) K
Triclinic
P ꢀ 1
200(2) K
Monoclinic
P 21/c
17.3657(5)
11.4420(4)
22.2480(6)
90
91.5510(10)
90
4419.0(2)
4
12.1695(5)
12.1789(6)
12.8051(6)
89.182(2)
76.368(2)
79.858(2)
1814.84(14)
2
b, Å
c, Å
a
, deg
, deg
b
g
, deg
Volume, Å3
Z
Crystal size, mm3 0.46 ꢃ 0.35 ꢃ 0.06 0.3 ꢃ 0.21 ꢃ 0.08 0.75 ꢃ 0.70 ꢃ 0.51
Refinement
method
Full-matrix least- Full-matrix least- Full-matrix least-
squares on F2
squares on F2
R1 ¼ 0.0353,
wR2 ¼ 0.0960
R1 ¼ 0.0467,
wR2 ¼ 0.1104
squares on F2
R1 ¼ 0.0252,
wR2 ¼ 0.0690
R1 ¼ 0.0682,
wR2 ¼ 0.0769
Final R indices
R1 ¼ 0.0471,
[I > 2sigma (I)] wR2 ¼ 0.1214
R indices (all data) R1 ¼ 0.0676,
wR2 ¼ 0.1310
Fig. 3. Molecular structure of complex 3b (hydrogen atoms and phenyl groups on dppe
except the ipso carbon are removed for clarity). Thermal ellipsoids are shown at the
30% level. Selected bond lengths [Å] and angles [deg]: Ru(1)eP(1), 2.2237(6); Ru(1)eP
(2), 2.2584(6); Ru(1)eC(36), 2.028(2); C(36)eC(37), 1.584(3); C(36)eC(39), 1.301(3); C
(37)eC(39), 1.495(3); P(1)eRu(1)eP(2), 85.52(2); Ru(1)eC(36)eC(37), 135.89(17); Ru
(1)eC(36)eC(39), 161.46(19); C(36)eC(39)eC(40), 157.5(2); C(37)eC(36)eC(39), 61.46
(17); C(36)eC(37)eC(39), 49.89(15); C(36)eC(39)eC(37), 68.65(18).
Largest diff. peak 1.901 and ꢀ0.602 1.171 and ꢀ0.999 0.834 and ꢀ0.400
and hole, Åꢀ3
CCDC number
776703
776704
794306
a
Crystals grown from an CH2Cl2eether mixture are found to incorporate an
CH2Cl2 molecule.

1284
H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
N3
Ph
N3
Ph
Ph
TMSN3
Ru
Ru
C
C
H
C
C
N
Ru
H
Ph2P
Ph2P
Ph2P
PPh2
PPh2
PPh2
3c
4c
NC
NC
NC
Scheme 4.
2c-N3
Ruthenium vinylidene complex 2a0 containing two PPh3 ligands
undergo a deprotonation reaction to yield cyclization product 3a0.
The reaction required greater span of time than dppe system.
Deprotonation reaction of complex 2a0 by n-Bu4NOH is followed by
the expected cyclization, yielding the cyclopropenyl complex 3a0
(Scheme 5). The reaction time needed is 4 h. Complex 3a0 is stable
in air and soluble in CH2Cl2, THF, and benzene, slightly soluble in
acetone and diethyl ether, but insoluble in CH3CN. The 31P NMR
X
Ph
Ph
H
base
acetone
RCH2X
reflux
[Ru]
C C
[Ru]
[Ru]
C
C
Ph
R
R
1'
3a', R=Ph
2a',R=Ph, X=Br
2b', R=CN, X=I
3b', R=CN
3c', R=p-C6H4-CN
2c', R=p-C6H4-CN, X=Br
spectrum of 3a0 displays two doublet resonances at
d 52.8 and 43.1
Ru
[Ru]=
with JPeP ¼ 27.6 Hz in C6D6 arising from the presence of a stereo-
Ph3P
genic center in the three-membered ring. In the 1H NMR spectrum
PPh3
of 3a0, the resonance of the methine proton appears at
d 2.62, and in
Scheme 5.
the 13C NMR spectrum, the triplet at 126.8 with JCeP ¼ 21.2 Hz is
assigned to Ca
. Deprotonation reaction of complexes 2a0 and 2c0
containing Ph and derivatives needed 10 h to yield cyclopropenyl
complexes 3a0 and 3c0. Complexes 2a0 and 2c0 needed longer
reaction time than complex 2b0 which indicates the acidic nature of
the methylene protons, which may be ascribed to the combined
effect of the cationic character and electron-withdrawing substit-
uents of the vinylidene complexes. In comparison with the dppe
system, the steric effect of the two PPh3 ligands may hinder the
electrophilic addition, therefore requiring longer reaction times.
The cyclopropenylruthenium complexes containing the triphenyl-
phosphine system therefore exhibits distinctive reactivity from that
of the bidentate ligand, such as dppe, dppp, or dppb.
2.6. Reaction of cyclopropenylruthenium complexes containing
indenyl and two PPh3 ligands with TMSN3
Cyclopropenylruthenium complexes containing Cp and triphe-
nylphosphine (PPh3) ligands reacting with TMSN3 conducted
similar reactivity with these cyclopropenyl complexes containing
indenyl and bidentate ligand [37,38]. Various substituents at the
three-membered ring cause different compounds.
To check the reactivity for the cyclopropenyl complexes con-
taining two PPh3 and indenyl ligands, complexes 2a0, 2b0 and 2c0 are
prepared from the reaction of organic halides and the ruthenium
acetylide complex [Ru]eC^CePh (10), ([Ru]]( 5-C9H7)(PPh3)2Ru).
h
2.7. Reaction of cyclopropenyl complexes 3a0e3c0 with TMSN3
Treatment of complex 10 with benzyl bromide at refluxing
temperature of CH2Cl2 for 18 h afforded cationic vinylidene
complex 2a0 in 85% yield. Similarly, preparation of other vinylidene
complexes 2b0 and 2c0 have been synthesized by reacting 10 with
the corresponding organic halides at refluxing temperature of
CH2Cl2 with good yields. Complexes 2a0e2c0 are all soluble in polar
solvent but insoluble in ether and hexane. The characteristic
spectroscopic data of these vinylidene complexes consist of
Treatment of the cyclopropenyl complex 3a0 with excess of
TMSN3 in THF at room temperature afforded [Ru]eN3 and the
organic product 6a (Scheme 6). The reaction conducted at room
temperature for 18 h and may proceed via N-coordinated complex
4a0. The N-coordinated complex 4a0 is unstable and undergoes
a further reaction with azide to give [Ru]eN3 and 6a. Similar
reaction occurred in the 3c0 with TMSN3 to yield [Ru]eN3 and the
corresponding organic product 6c.
strongly deshielded C
a
resonance as a triplet at
d
345 ꢂ 2 in the 13
C
NMR spectrum and a singlet 31P NMR resonance normally at
In contrast with the results in dppe ligand system, complexes
containing relatively large sterically two PPh3 ligands make 4a0 and
around
d
38 ꢂ 1 in CDCl3 at room temperature, which is due to the
4c0 unstable. Further Nꢀ3 attack C
a to give final [Ru]eN3 and the
fluxional behavior of the vinylidene ligand [70].
N3
Ph
Ph
Ph
H
TMSN3
R
+
N3
[Ru]
[Ru]
[Ru]
N
C
C
NC
H
R=p-C6H4-CN,
R
R
6a, R=Ph
Ph
4a', R=Ph
4b', R=CN
6c, R=p-C6H4-CN
3a', R=Ph
3b', R=CN
4c', R=p-C6H4-CN
3c', R=p-C6H4-CN
R=CN
N
N
Ph
Ru
Ph
N
[Ru]
[Ru]=
CN
[Ru] N3
+
+
NC
Ph3P
N
PPh3
NC
6b
5b' (major)
Scheme 6.

H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
1285
corresponding organic products. In this system, the stereo effect
may play an important role in the reactivity of the cyclopropenyl
complexes with TMSN3. The bond angle P(1)eRu(1)eP(2) of 85.52
(2) in complex 3b is similar to the cyclopropenyl complex con-
taining Cp and dppe ligand [54]. But smaller than that in the system
containing Cp and dppp ligand [40] and is also smaller than those
cyclopropenyl complexes containing Cp and two triphenylphos-
phine ligands [39]. In the iron cyclopropenyl complex containing
dppe ligand, the bond angle P(1)eFe(1)eP(2) of 84.81(4) is also
similar to complex 3b [55].
following the methods reported in literature. The following atom
labels have been used for the 1H and 13C{1H} spectroscopic data:
7
1
7a
6
2
5
3a
3
4
When CN substituent at the sp3 C is in the ruthenium cyclo-
propenyl ring, complex 3b0 react with TMSN3 yielding the N-
coordinated complex 4b0 initially. Further 4b0 react with Nꢀ3 by the
[3 þ 2] cycloaddition yielded the tetrazolate complex 5b0 as the
stable solids in room temperature. The minor product [Ru]eN3 and
the corresponding organic product 6b can be observed. A similar
result occurred in the reaction of 3b and 3b0 each containing dppe
and two PPh3 system with TMSN3. The electron-withdrawing and
the stereo effects of the CN group in the N-coordinated complex 4b
may enhance the [3 þ 2] cycloaddition with the CN group coordi-
nated with the metal and Nꢀ3 to give the tetrazolate complex.
Complex 4b0 is obtained by the similar pathway. The minor product
[Ru]eN3 and the corresponding organic product 6b is considered
the reaction of 4b0 and the N3ꢀ group.
4.1. Synthesis of [(
h
5-C9H7)(dppe)Ru]C]C(Ph)CH2Ph][Br] (2a)
To a solution of 1 (0.21 g, 0.29 mmol) in 20 ml of CH2Cl2 was
added benzyl bromide (0.17 ml, 1.45 mmol). After stirring overnight
at room temperature, the resulting solution was concentrated to
about 5 ml. The residue was then slowly added to 40 ml of vigor-
ously stirred diethyl ether. The pink precipitate thus formed was
filtered off, washed with diethyl ether and hexane and dried under
vacuum to give pink product 2a in 79% yield (0.19 g, 0.23 mmol).
Spectroscopic data for 2a follows. 1H NMR (CDCl3):
37H, H of Ph and indenyl group); 3.01 (m, 4H, 2CH2 of dppe); 2.80
(s, 2H, CH2). 31P NMR (CDCl3): 76.1. 13C NMR (CDCl3): 352.2 (C
JCeP ¼ 17.0 Hz); 138.3e128.1 (Ph); 126.9 (C-5, 6); 123.7 (C-4, 7);
d 7.42e5.83 (m,
d
a,
112.3 (Cb); 97.3 (C-2); 79.9 (C-1, 3); 28.9 (CH2); 27.9 (t,
JCeP ¼ 23.8 Hz, CH2 of dppe). HRMS (ESI, m/z): 807.4 (Mþ); 615.4
(Mþ ꢀ C2(Ph)CH2Ph). Anal. Calcd. for C50H43P2BrRu: C: 67.72, H:
4.89, found: C: 68.01, H: 4.92.
3. Concluding remarks
Ruthenium cyclopropenyl complexes containing indenyl and
dppe or two triphenylphosphine ligands can be synthesized. These
complexes are stable in the solid state in room temperature.
Various substituents at the sp3 carbon of the three-membered ring
govern the reactivity of the cyclopropenyl complexes with TMSN3.
Reaction of the cyclopropenyl complexes 3a and 3c containing the
4.2. Synthesis of [(h
5-C9H7)(dppe)Ru]C]C(Ph)CH2CN][I] (2b)
1 (0.30 g, 0.42 mmol) and iodoacetonitrile (0.15 ml, 2.07 mmol)
were stirred overnight in 20 ml of CH2Cl2. The purification method
described for 2a yielded pink solid product 2b (0.27 g, 0.36 mmol)
in 86% yield. Spectroscopic data for 2b follows. 1H NMR (CDCl3):
phenyl and its derivatives at Cg yield the stable N-coordinated
complexes. Reaction of complex 3b containing a CN group at C
g
d
7.50e6.94 (m, 27H, 25H of Ph, 2H of indenyl group); 6.67, 6.07 (m,
with TMSN3 yields the tetrazolate ruthenium complex 5b via the
[3 þ 2] cycloaddition of Nꢀ3 with the N-coordinated product.
Reaction of the cyclopropenyl complexes containing two PPh3
ligands 3a0 and 3c0 with TMSN3 yields the [Ru]eN3 and the corre-
sponding organic product as the final product. The N-coordinated
complexes are considered to be intermediate in the reaction.
2H each one, H of indenyl group); 5.96 (br, 1H of indenyl group);
3.17, 2.84 (m, 4H, 2CH2 of dppe); 2.40 (s, 2H, CH2). 31P NMR (CDCl3):
d
74.5. 13C NMR (CDCl3): 347.8 (C
a
, JCeP ¼ 16.4 Hz); 132.5e128.9
(Ph); 126.9 (C-5, 6); 123.6 (C-4, 7); 112.6 (C ); 97.4 (C-2); 80.9 (C-1,
3); 27.9 (t, JCeP ¼ 22.7 Hz, CH2 of dppe); 13.3 (CH2). HRMS (ESI, m/z):
756.6 (Mþ); 615.3 (Mþ
C2(Ph)CH2CN). Anal. Calcd. for
C45H38NP2IRu: C: 61.23, H: 4.34, found: C: 61.45, H: 4.39.
b
ꢀ
Further, by the reaction of Nꢀ3 attack at C
a yields the final products.
When the cyclopropenyl complex 3b0 containing CN group at C
g
reacts with TMSN3, the tetrazolate complex 5b0 can be obtained as
4.3. Synthesis of [(h
5-C9H7)(dppe)Ru]C]C(Ph)CH2(p-C6H4-CN)]
[Br] (2c)
the major product.
1 (0.37 g, 0.52 mmol) and
a-bromo-p-tolunitrile (0.42 g,
4. Experimental section
2.14 mmol) were stirred overnight in 20 ml of CH2Cl2. The purifi-
cation method described for 2a yielded pink solid product 2c in 71%
All reagents were purchased from commercial sources and used
without further purification. NMR spectra were obtained with
Bruker-AC 500 spectrometer at 500 MHz (1H), 202 MHz (31P), or
125 MHz (13C). The chemical shifts are given in parts per million
yield (0.31 g, 0.37 mmol). 1H NMR (CDCl3):
d 7.42e6.88 (m, 31H,
29H of Ph, 2H of indenyl group); 6.52, 5.90 (m, 2H each one, H of
indenyl group); 5.82 (br, 1H of indenyl group); 3.12 (m, 4H, 2CH2 of
dppe); 2.90 (s, 2H, CH2). 31P NMR (CDCl3):
d
76.1. 13C NMR (CDCl3):
from SiMe4 (1H and 13C{1H}) or 85% H3PO4
(
31P{1H}) and are
. The Mass spectra were recorded using LCQ
343.4 (C
(C-4, 7); 114.9 (C
a
, JCeP ¼ 16.1 Hz); 131.8e127.5 (Ph); 126.3 (C-5, 6); 122.8
reported in unit
d
b
); 98.1 (C-2); 81.4 (C-1, 3); 28.5 (t, JCeP ¼ 22.4 Hz,
advantage (ESI). X-ray diffraction studies were both carried out at
the Regional Center of Analytical Instrument at the National Taiwan
Normal University.
CH2 of dppe); 12.8 (CH2). HRMS (ESI, m/z): 832.3 (Mþ); 615.2
(Mþ ꢀ C2(Ph)CH2C6H4CN). Anal. Calcd. for C51H42NP2BrRu: C: 67.18,
H: 4.64, found: C: 67.33, H: 4.67.
All synthetic manipulations were performed in oven-dried
glassware under nitrogen using vacuum-line and standard Schlenk
techniques. Solvents were dried by standard methods and distilled
under nitrogen before use. THF was distilled from sodium benzo-
phenone ketyl and CH2Cl2 was distilled from CaH2. Methanol was
4.4. Synthesis of [(h5-C9H7)(PPh3)2Ru]C]C(Ph)CH2Ph][Br] (2a0)
To a solution of 10 (0.23 g, 0.27 mmol) in 20 ml of CH2Cl2 was
added benzyl bromide (0.22 ml, 1.84 mmol). After refluxing for 18 h,
the resulting solution was cooled to room temperature and
distilled from Mg/I2. Complexes (
h
5-C9H7)(dppe)RueC^CePh (1)
[49] and (h5-C9H7)(PPh3)2RueC^CePh (10) [71] were prepared by

1286
H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
concentrated to about 5 ml. The residue was then slowly added to
40 ml of vigorously stirred diethyl ether. The pink precipitate thus
formed was filtered off, washed with diethyl ether and hexane and
dried under vacuum to give pink product 2a0 in 85% yield (0.21 g,
0.23 mmol). Spectroscopic data for 2a0 follows. 1H NMR (CDCl3):
0.5 ml. Then 5 ml CH3CN was added the yellow precipitate thus
formed was filter off and washed with CH3CN and dried under
vacuum to give the product 3b (0.29 g, 0.25 mmol) in 78% yield.
Spectroscopic data for 3b are as follows.1H NMR (CDCl3):
d 7.61e6.85
(m, 25H of Ph group); 6.67, 6.51 (m, 2H each one, H of indenyl group);
5.96, 5.33, 4.81 (m, 1H each one, H of indenyl group); 2.56, 2.05, 1.86
d
7.46e6.28 (m, 40H, Ph); 6.28 (br, 1H, H-2); 5.65 (br, 2H of H-4, 7);
5.33 (d, 2H, H-1, 3, JHeH ¼ 2.3 Hz); 3.49 (s, 2H, CH2). 31P NMR (CDCl3):
(m, 4H, of dppe); 0.65 (s, 1H, CH). 31P NMR (CDCl3):
d 94.3, 88.6 (AX,
d
39.0. 13C NMR (CDCl3): 344.4 (C
a); 137.5e126.6 (Ph); 123.3 (C-4, 7);
JPeP ¼ 24.8 Hz). 13C NMR (CDCl3): 142.2e123.6 (Ph); 127.9 (C
a,
100.0 (C-2); 81.1 (C-1, 3); 31.9 (CH2). HRMS (ESI, m/z): 933.2 (Mþ);
671.1 (Mþ ꢀ PPh3); 479.0 (Mþ ꢀ PPh3, C2(Ph)CH2Ph). Anal. Calcd. for
C60H49P2BrRu: C: 71.14, H: 4.88, found: C: 71.98, H: 5.11.
JCeP ¼ 10.1 Hz); 113.1 (CN); 109.7 (C-5, 6); 109.6 (C-4, 7); 93.1 (C-2);
71.4 (C-1, 3); 28.2 (t, JCeP ¼ 22.3 Hz, CH2 of dppe); 5.4 (CH). HRMS (ESI,
m/z): 756.1 (Mþ þ 1); 615.7 (Mþ þ 1 ꢀ C2(Ph)CHCN). Anal. Calcd. for
C45H37NP2Ru: C: 71.61, H: 4.94, found: C: 71.89, H: 5.03.
4.5. Synthesis of [(h5-C9H7)(PPh3)2Ru]C]C(Ph)CH2CN][I] (2b0)
4.9. Synthesis of cyclopropenylruthenium complex (h
5-C9H7)(dppe)
10 (0.28 g, 0.33 mmol) and iodoacetonitrile (0.15 ml, 2.07 mmol)
were refluxed for 18 h in 20 ml of CH2Cl2. The purification method
described for 2a0 yielded pink solid product 2b0 (0.26 g, 0.29 mmol)
in 88% yield. Spectroscopic data for 2b0 follows. 1H NMR (CDCl3):
RueC]C(Ph)CH(p-C6H4eCN) (3c)
2c (0.28 g, 0.35 mmol) in 2 ml of acetone was treated with
n-Bu4NOH (1 M in MeOH) (2 ml, 2.0 mmol). After stirring at room
temperature for 2 h, the resulting solutionwas concentrated to about
0.5 ml. Then 5 ml CH3CN was added the yellow precipitate thus
formed was filter off and washed with CH3CN and dried under
vacuum to give the product 3c (0.26 g, 0.31 mmol) in 86% yield.
d
7.50e6.63 (m, 35H of Ph group); 6.62, 5.44, 4.74 (m, 2H each one, H
of indenyl group); 5.63 (br, 1H of indenyl group); 3.52 (s, 2H, CH2).
31P NMR (CDCl3): 37.3. 13C NMR (CDCl3): 346.3 (C
, JCeP ¼ 16.3 Hz);
); 97.4 (C-2);
d
a
133.1e127.7 (Ph); 127.2 (C-5, 6); 123.3 (C-4, 7); 112.3 (C
b
81.2 (C-1, 3); 14.1 (CH2). HRMS (ESI, m/z): 882.1 (Mþ); 620.4
(Mþ ꢀ PPh3). Anal. Calcd. for C55H44NP2IRu: C: 65.48, H: 4.40, found:
C: 65.59, H: 4.48.
Spectroscopic data for 3c are as follows.1H NMR (CDCl3):
d 7.47e6.83
(m, 25H of Ph group); 6.81, 6.38, 6.43, 5.22, 5.21, 4.95 (m, 7H of
indenyl group); 2.51, 2.46, 1.79 (m, 4H, of dppe); 1.42 (s, 1H, CH). 31P
NMR (CDCl3):
138.4e121.7 (Ph); 128.2 (C
d
92.6, 89.6 (AX, JPeP ¼ 24.2 Hz). 13C NMR (CDCl3):
4.6. Synthesis of [(
h
5-C9H7)(PPh3)2Ru]C]C(Ph)CH2(p-C6H4eCN)]
a
, JCeP ¼ 11.4 Hz); 112.0 (CN); 111.3 (C-5, 6);
[Br] (2c0)
110.7 (C-4, 7); 96.2 (C-2); 73.7 (C-1, 3); 27.4 (t, JCeP ¼ 20.6 Hz, CH2 of
dppe); 13.1 (CH). HRMS (ESI, m/z): 832.6 (Mþ
þ
1); 615.8
10 (0.34 g, 0.40 mmol) and
a
-bromo-p-tolunitrile (0.42 g,
(Mþ þ 1 ꢀ C2(Ph)CHC6H4CN). Anal. Calcd. for C51H41NP2Ru: C: 73.72,
2.14 mmol) were refluxed for 18 h in 20 ml of CH2Cl2. The purifi-
cation method described for 2a0 yielded pink solid product 2c0 in
78% yield (0.30 g, 0.31 mmol). Spectroscopic data for 2c0 follows. 1H
H: 4.97, found: C: 73.87, H: 4.99.
4.10. Synthesis of cyclopropenylruthenium complex (h
5-C9H7)
(PPh3)2RueC]C(Ph)CHPh (3a0)
NMR (CDCl3):
2H of H-4, 7); 5.41 (br, 2H, H-1, 3); 3.61 (s, 2H, CH2). 31P NMR
(CDCl3):
38.8. 13C NMR (CDCl3): 343.7 (t, C
d
7.48e6.57 (m, 39H, Ph); 6.93 (br, 1H, H-2); 5.60 (br,
d
a
, JCeP ¼ 16.9 Hz); 143.3
To a solution of 2a0 (0.27 g, 0.29 mmol) in 10 ml of acetone was
added a solution of n-Bu4NOH (2 ml, 2 mmol, 1 M in MeOH). After
the mixture was stirred at room temperature for 10 h, the resulting
solution was concentrated to about 0.5 ml. Then 5 ml CH3CN was
added the yellow precipitate thus formed was filter off and washed
with CH3CN and dried under vacuum to give the product 3a0
(0.23 g, 0.25 mmol) in 86% yield. Spectroscopic data for 3a0 are as
(CN); 134.3e128.0 (Ph); 123.5 (C-4, 7); 101.3 (C-2); 81.6 (C-1, 3);
32.0 (CH2). HRMS (ESI, m/z): 958.2 (Mþ); 696.1 (Mþ ꢀ PPh3). Anal.
Calcd. for C61H48NP2BrRu: C: 70.59, H: 4.66, found: C: 70.83, H:
4.68.
4.7. Synthesis of cyclopropenylruthenium complex (h
5-C9H7)(dppe)
RueC]C(Ph)CHPh (3a)
follows: 1H NMR (C6D6):
d 7.45e6.95 (m, 40H of Ph group); 6.88,
6.60, 5.82, 5.58, 5.42, 4.88 (m, 7H of indenyl group); 2.62 (s, 1H, CH).
2a (0.25 g, 0.31 mmol) in 2 ml of acetone was treated with n-
Bu4NOH (1 M in MeOH) (2 ml, 2.0 mmol). After stirring at room
temperature for 2 h, the resulting solutionwas concentrated to about
0.5 ml. Then 5 ml CH3CN was added the yellow precipitate thus
formed was filter off and washed with CH3CN and dried under
vacuum to give the product 3a (0.18 g, 0.22 mmol) in 71% yield.
31P NMR (C6D6):
133.1e123.5 (Ph); 126.8 (C
4, 7); 98.4 (C-2); 80.1(C-1, 3); 11.9 (CH). HRMS (ESI, m/z): 933.1
(Mþ þ 1); 671.1 (Mþ þ 1 ꢀ PPh3); 429.0 (Mþ þ 1 ꢀ PPh3, C2(Ph)
CHPh). Anal. Calcd. for C60H48P2Ru: C: 77.32, H: 5.19, found: C:
77.54, H: 5.22.
d
52.8, 43.1 (AX, JPeP ¼ 27.6 Hz). 13C NMR (C6D6):
a
, JCeP ¼ 21.2 Hz); 110.3 (C-5, 6); 109.3 (C-
Spectroscopic data for 3a are as follows.1H NMR (CDCl3):
(m, 37H, H of Ph and indenyl group); 2.59, 2.17,1.85,1.55 (m, 4H, 2CH2
d 7.42e5.08
4.11. Synthesis of cyclopropenylruthenium complex (h
5-C9H7)
(PPh3)2RueC]C(Ph)CHCN (3b0)
of dppe); 1.37 (s, 1H, CH). 31P NMR (CDCl3):
d
92.6, 90.2 (AX,
JPeP ¼ 23.3 Hz). 13C NMR (CDCl3): 135.5e126.4 (Ph); 124.1 (C
a,
JCeP ¼ 9.5 Hz); 110.3 (C-5, 6); 108.8 (C-4, 7); 94.7 (C-2); 78.2 (C-1, 3);
27.8 (t, JCeP ¼ 21.5 Hz, CH2 of dppe); 12.3 (CH). HRMS (ESI, m/z): 807.6
(Mþ þ 1); 615.7 (Mþ þ 1 ꢀ C2(Ph)CHPh). Anal. Calcd. for C50H42P2Ru:
C: 74.52, H: 5.25, found: C: 74.75, H: 5.27.
A sample of 2b0 (0.24 g, 0.27 mmol) was dissolved in 10 ml of
acetone at room temperature. A methanol solvent of n-Bu4NOH
(2 ml, 2 mmol, 1 M in MeOH) was added. After the mixture stirred
for 4 h, the resulting solution was concentrated to about 0.5 ml.
Then 5 ml CH3CN was added the yellow precipitate thus formed
was filter off and washed with CH3CN. The product was dried under
vacuum and identified as 3b0 (0.21 g, 0.24 mmol) in 89% yield.
Spectroscopic data for 3b0 are as follows: 1H NMR (CDCl3):
4.8. Synthesis of cyclopropenylruthenium complex (h
5-C9H7)(dppe)
RueC]C(Ph)CHCN (3b)
2b (0.24 g, 0.32 mmol) in 2 ml of acetone was treated with
n-Bu4NOH (1 M in MeOH) (2 ml, 2.0 mmol). After stirring at room
temperature for 2 h, the resulting solutionwas concentrated to about
d 7.16e6.88 (m, 35H of Ph group); 6.84, 6.05, 5.92, 5.31, 5.00 (m, 7H
of indenyl group); 1.61 (s, 1H, CH). 31P NMR (CDCl3):
d 53.9, 49.9
(AX, JPeP ¼ 28.1 Hz). 13C NMR (CDCl3): 134.6e125.1 (Ph); 126.5 (C
a,

H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
1287
JCeP ¼ 22.5 Hz); 113.8 (CN); 112.4 (C-5, 6); 111.5 (C-4, 7); 94.5 (C-2);
4.15. Reaction of 3c with TMSN3
78.1 (C-1, 3); 6.5 (CH). HRMS (ESI, m/z): 882.4 (Mþ þ 1); 620.3
(Mþ þ 1 ꢀ PPh3); 429.1 (Mþ þ 1 ꢀ PPh3, C2(Ph)CHCN).Anal. Calcd.
for C55H43NP2Ru: C: 74.99, H: 4.92, found: C: 75.18, H: 4.93.
To a solution of 3c (0.16 g, 0.19 mmol) in THF (5 ml) was added
TMSN3 (0.1 ml, 0.76 mmol). The solution was stirred at room
temperature for 4 h, then the solvent was reduced to about 2 ml, and
slowlyadded to 20 ml of stirring hexane. The yellow precipitates thus
formed were filtered off and wash with hexane and identified as 4c
(0.12 g, 0.14 mmol) in 74% yield. Spectroscopic data for 4c are as
4.12. Synthesis of cyclopropenylruthenium complex (h
5-C9H7)
(PPh3)2RueC]C(Ph)CH(p-C6H4eCN) (3c0)
follows.1H NMR (CDCl3):
d 7.58e7.11 (m, 30H of Ph group); 6.69, 6.43
(m, 2H each one, H of indenyl group); 5.00, 4.96, 4.83 (br, 1H each
one, H of indenyl group); 4.37 (t, 1H, NCCH(Ph)CH2, JHeH ¼ 7.40 Hz);
2.68, 2.52 (m, 4H, 2CH2 of dppe); 2.45 (m, 2H, CH(Ph)CH2). 31P NMR
A sample of 2c0 (0.26 g, 0.27 mmol) was dissolved in 10 ml of
acetone at room temperature. A methanol solvent of n-Bu4NOH
(2 ml, 2 mmol,1 M in MeOH) was added. After the mixture stirred for
10 h, the resulting solution was concentrated to about 0.5 ml. Then
5 ml CH3CN was added the yellow precipitate thus formed was filter
off and washed with CH3CN. The product was dried under vacuum
and identified as 3c0 (0.23 g, 0.24 mmol) in 89% yield. Spectroscopic
(CDCl3):
d
83.9, 81.2 (AX, JPeP ¼ 27.1 Hz). 13C NMR (CDCl3):
136.8e124.2 (Ph); 118.5 (CN); 109.3, 104.8 (C of indenyl group); 92.7
(C of indenyl group); 64.8 (C of indenyl group); 43.1 (NCH(Ph)); 41.2
(NCH(Ph)CH2); 25.3 (t, JCeP ¼ 21.2 Hz, CH2 of dppe). HRMS (ESI, m/z):
851.4 (Mþ); 615.1 (Mþ ꢀ NC2(Ph)HCH2C6H4CN). Anal. Calcd. for
C51H43P2N5Ru: C: 68.91, H: 4.88, found: C: 69.09, H: 4.90.
data for 3c0 are as follows: 1H NMR (C6D6):
d 7.43e6.92 (m, 39H of Ph
group); 6.92, 6.62, 5.79, 5.62, 5.40, 4.92 (m, 7H of indenyl group);
2.60 (s, 1H, CH). 31P NMR (C6D6):
NMR (C6D6): 138.1e126.7 (Ph); 128.1 (C
110.5 (C-5, 6); 110.1 (C-4, 7); 93.2 (C-2); 80.7 (C-1, 3); 8.4 (CH). HRMS
(ESI, m/z): 958.1 (Mþ þ 1); 696.0 (Mþ þ 1 ꢀ PPh3); 429.0
(Mþ þ 1 ꢀ PPh3, C2(Ph)CHC6H4CN). Anal. Calcd. for C61H47NP2Ru: C:
76.55, H: 4.95, found: C: 76.74, H: 4.97.
d
53.1, 45.1 (AX, JPeP ¼ 27.8 Hz). 13
C
a
, JCeP ¼ 18.7 Hz); 111.9 (CN);
4.16. Reaction of 3a0 with TMSN3
To a flask with 3a0 (0.14 g, 0.15 mmol) in THF (15 ml), TMSN3
(0.1 ml, 0.76 mmol) was added. The mixture was stirred for 18 h then
the resulting orange solution was dried under vacuum. The mixture
was added to a stirred hexane. Orange precipitates thus formed were
filtered off and washed with diethyl ether. The organometallic
product was identified as [Ru]eN3 (0.074 g, 0.09 mmol) in 60% yield.
The organic product was extracted with hexane and collected by
extraction with hexane and purified by chromatography, then, the
solvent was removed under vacuum to give 6a (0.016 g, 0.087 mmol)
in 58% yield [38].
4.13. Reaction of 3a with TMSN3
To a solution of 3a (0.14 g, 0.17 mmol) in THF (5 ml) was added
TMSN3 (0.1 ml, 0.76 mmol). The solution was stirred at room
temperature for 4 h. Then the solvent was reduced to about 2 ml,
and slowly added to 20 ml of stirring hexane. The yellow precipi-
tates thus formed were filtered off and wash with hexane and
identified as 4a (0.09 g, 0.11 mmol) in 65% yield. Spectroscopic data
4.17. Reaction of 3b0 with TMSN3
for 4a are as follows. 1H NMR (CDCl3):
d 7.48e7.11 (m, 30H, H of Ph
group); 6.55, 6.41 (m, 2H each one, H of indenyl group); 4.99, 4.87,
4.78 (br, 1H each one, H of indenyl group); 3.84 (t, 1H, NCCH(Ph)
CH2, JHeH ¼ 7.14 Hz); 2.56 (m, 4H, 2CH2 of dppe); 2.45 (m, 2H, CH
To a solution of 3b0 (0.15 g, 0.17 mmol) in THF (5 ml) was added
TMSN3 (0.1 ml, 0.76 mmol). The solution was stirred at room
temperature for 18 h. Then the solvent was reduced to about 2 ml,
and slowly added to 20 ml of stirring hexane. The yellow precipitates
thus formed were filtered off and wash with hexane and identified as
5b0 and [Ru]eN3 (the mixture is 0.12 g) in 10:1 ratio. The organic
product was extracted with hexane and collected by extraction with
hexane and purified by chromatography, then, the solvent was
removed under vacuum to give 6b (0.012 g, 0.077 mmol) in 45% yield.
Spectroscopic data for 5b0 are as follows: 1H NMR (CDCl3):
(Ph)CH2). 31P NMR (CDCl3):
d
83.3, 81.4 (AX, JPeP ¼ 27.3 Hz). 13C
NMR (CDCl3): 137.2e126.8 (Ph); 123.7 (CN); 107.7, 106.9 (C of
indenyl group); 91.8 (C of indenyl group); 65.3 (C of indenyl group);
41.2 (NCH(Ph)); 39.8 (NCH(Ph)CH2); 27.6 (t, JCeP ¼ 22.5 Hz, CH2 of
dppe). HRMS (ESI, m/z): 821.8 (Mþ); 615.7 (Mþ ꢀ NC2(Ph)HCH2Ph).
Anal. Calcd. for C50H44P2N4Ru: C: 69.51, H: 5.13, found: C: 69.74, H:
5.14.
d
7.41e7.01 (m, 35H, H of Ph group); 6.97, 6.72 (m, 2H each one, H of
4.14. Reaction of 3b with TMSN3
indenyl group); 5.23, 5.01, 4.87 (br, 1H each one, H of indenyl
group); 3.24 (t, 1H, NCCH(Ph)CH2, JHeH ¼ 6.82 Hz); 2.62, 2.48 (AB,
2H, CH(Ph)CH2, JHeH ¼ 5.6, 15.8 Hz and, JHeH ¼ 8.5, 15.8 Hz); 2.33,
To a solution of 3b (0.16 g, 0.21 mmol) in THF (5 ml) was added
TMSN3 (0.1 ml, 0.76 mmol). The solution was stirred at room
temperature for 4 h. Then the solvent was reduced to about 2 ml,
and slowly added to 20 ml of stirring hexane. The yellow precipi-
tates thus formed were filtered off and wash with hexane and
identified as 5b (0.13 g, 0.17 mmol) in 81% yield. Spectroscopic data
2.17 (m, 2H each, 2CH2 of dppe). 31P NMR (CDCl3):
d 47.6, 47.4 (AX,
JPeP ¼ 37.3 Hz). 13C NMR (CDCl3): 161.4 (NCN); 137.2e126.3 (Ph);
114.5 (CN); 107.2, 106.8 (C of indenyl group); 93.8 (C of indenyl
group); 71.3 (C of indenyl group); 41.6 (NCH(Ph)); 28.3 (NCH(Ph)
CH2). HRMS (ESI, m/z): 939.4 (Mþ); 741.2 (Mþ ꢀ N4C2(Ph)HCH2CN).
Anal. Calcd. for C55H45P2N5Ru: C: 70.35, H: 4.83, found: C: 70.51, H:
4.85. Spectroscopic data for 6b are as follows: 1H NMR (CDCl3):
for 5b are as follows. 1H NMR (CDCl3):
d 7.41e6.89 (m, 25H, H of Ph
group); 6.82, 6.49 (m, 2H each one, H of indenyl group); 4.80, 4.78,
4.62 (br, 1H each one, H of indenyl group); 3.76 (t, 1H, NCCH(Ph)
CH2, JHeH ¼ 7.16 Hz); 3.05, 2.57 (m, 2H each, 2CH2 of dppe); 2.10,
1.95 (AB, 2H, CH(Ph)CH2, JHeH ¼ 5.3, 16.7 Hz and, JHeH ¼ 9.0,
d
7.35e7.12 (m, 5H of Ph group); 3.14 (dd, 1H, NCCH(Ph), JHeH ¼ 6.5,
7.2 Hz); 2.71, 2.48 (AX, 2H, CH2CN, JHeH ¼ 7.3,12.9 Hz and JHeH ¼ 6.7,
12.9 Hz). 13C NMR (CDCl3):
d 142.5e126.8 (Ph); 114.3 (CN); 38.2
16.7 Hz). 31P NMR (CDCl3):
d
93.3, 85.6 (AX, JPeP ¼ 27.7 Hz). 13C NMR
(CH2); 33.1 (CH). MS (EI): 156 (Mþ). Anal. Calcd. for C10H8N2: C:
76.90, H: 5.16, found: C: 77.12, H: 5.17.
(CDCl3): 158.7 (NCN); 138.5e127.1 (Ph); 112.9 (CN); 106.3, 106.1 (C
of indenyl group); 92.4 (C of indenyl group); 68.1 (C of indenyl
group); 39.8 (NCH(Ph)); 27.6 (t, JCeP ¼ 22.3 Hz, CH2 of dppe); 23.1
(NCH(Ph)CH2). HRMS (ESI, m/z): 813.8 (Mþ); 615.1 (Mþ ꢀ N4C2(Ph)
HCH2CN). Anal. Calcd. for C45H39P2N5Ru: C: 66.49, H: 4.84, found:
C: 66.65, H: 4.87.
4.18. Reaction of 3c0 with TMSN3
To a flask with 3c0 (0.14 g, 0.15 mmol) in THF (15 ml), TMSN3
(0.1 ml, 0.76 mmol) was added. The mixture was stirred for 18 h then

1288
H.-L. Sung, H.-L. Hsu / Journal of Organometallic Chemistry 696 (2011) 1280e1288
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the resulting orange solution was dried under vacuum. The mixture
was added to a stirred hexane. Orange precipitates thus formed
were filtered off and washed with diethyl ether. The organometallic
product was identified as [Ru]eN3 (0.072 g, 0.092 mmol) in 61%
yield. The organic product was extracted with hexane and collected
by extraction with hexane and purified by chromatography, then,
the solvent was removed under vacuum to give 6c (0.018 g,
0.078 mmol) in 52% yield.
Spectroscopic data for 6c are as follows: 1H NMR (C6D6):
d
7.41e6.69 (m,10H, Ph); 3.28 (dd,1H, NCCH(Ph), JHeH ¼ 6.7, 7.8 Hz);
2.63, 2.54 (AX, 2H, CH2C6H4CN, JHeH ¼ 7.8, 13.6 Hz and JHeH ¼ 6.7,
13.6 Hz). 13C NMR (C6D6):
d 141.4e127.5 (Ph); 119.2 (CN); 40.1(CH2);
36.9 (CH). MS (EI): 232 (Mþ). Anal. Calcd. for C16H12N2: C: 82.73, H:
5.20, found: C: 82.75, H: 5.22.
Acknowledgments
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We are grateful for support of this work from the National
Science Council of the Republic of China (NSC Grant No. 97-2113-M-
003-007-MY2) and National Taiwan Normal University (98031022)
for financial support.
Appendix. Supplementary material
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CCDC-776703, 776704, 794306 (see Table 1) contain the
supplementary crystallographic data for this paper. These data can
be obtained free of charge from The Cambridge Crystallographic
Data Center via www.ccdc.cam.ac.uk/data_request/cif.
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