Cyclization Reactions of Ruthenium Vinylidene Complexes

Article abstract of DOI:10.1021/om9901978

Treatment of [Ru]-C=C(Ph)C(=NPh)S (2, [Ru] = (η⁵-C₅H₅)(dppe)Ru, dppe = Ph₂PCH₂-CH₂PPh₂) with ICH₂CN at room temperature affords the S-alkylation product [Ru]=C= C(Ph)C(=NPh)SCH₂R⁺ (3a, R = CN). Deprotonation of 3a by n-Bu₄NOH in acetone induces a novel cyclization reaction and yields the neutral five-membered-ring heterocyclic complex [Ru]-C=C(Ph)C(=NPh)SCHCN (5a), which isomerizes to the 2-aminothiophene complex [Ru]-C=C(CN)SC(NHPh)=C(Ph) (6a). Treatment of 2 with organic bromides BrCH₂R affords both S-alkylation products (3b, R = CO₂CH₃; 3c, R = p-C₆H₄CN; 3d, R = Ph) and N-alkylation products [Ru]=C=C(Ph)C(=S)NPhCH₂R⁺ (4b, R = CO₂CH₃; 4c, R = p-C₆H₄CN; 4d, R = Ph) in varying ratios. Base-induced cyclization of a mixture of 3b and 4b occurs only for the 3b component to afford [Ru]-C=C(Ph)CC=NPh)SCHCO₂CH₃ (5b), whereas cyclization of a mixture of 3c and 4c occurs for both complexes, yielding 5c and the pyrrole-2-thione complex [Ru]-C=C(Ph)C(=S)N(Ph)CH(p-C₆H₄CN) (7c), respectively. Cyclization of a 3d-4d mixture occurs only for 4d to afford [Ru]-C=C(Ph)C(=S)NPhCHPh (7d). The structures of 6a and 7c were determined by single-crystal X-ray diffraction analysis.

Full text of DOI:10.1021/om9901978

Organometallics 1999, 18, 3445-3450
3445
Cycliza tion Rea ction s of Ru th en iu m Vin ylid en e
Com p lexes
Chao-Wan Chang, Ying-Chih Lin,* Gene-Hsiang Lee, and Yu Wang
Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China
Received March 22, 1999
Treatment of [Ru]-CdC(Ph)C(dNPh)S (2, [Ru] ) (η5-C5H5)(dppe)Ru, dppe ) Ph2PCH2-
CH2PPh2) with ICH2CN at room temperature affords the S-alkylation product [Ru]dCd
C(Ph)C(dNPh)SCH2R+ (3a , R ) CN). Deprotonation of 3a by n-Bu4NOH in acetone induces
a novel cyclization reaction and yields the neutral five-membered-ring heterocyclic complex
[Ru]-CdC(Ph)C(dNPh)SCHCN (5a ), which isomerizes to the 2-aminothiophene complex
[Ru]-CdC(CN)SC(NHPh)dC(Ph) (6a ). Treatment of 2 with organic bromides BrCH2R affords
both S-alkylation products (3b, R ) CO2CH3; 3c, R ) p-C6H4CN; 3d , R ) Ph) and N-alkylation
products [Ru]dCdC(Ph)C(dS)NPhCH2R+ (4b, R ) CO2CH3; 4c, R ) p-C6H4CN; 4d , R )
Ph) in varying ratios. Base-induced cyclization of a mixture of 3b and 4b occurs only for the
3b component to afford [Ru]-CdC(Ph)C(dNPh)SCHCO2CH3 (5b), whereas cyclization of a
mixture of 3c and 4c occurs for both complexes, yielding 5c and the pyrrole-2-thione complex
[Ru]-CdC(Ph)C(dS)N(Ph)CH(p-C6H4CN) (7c), respectively. Cyclization of a 3d -4d mixture
occurs only for 4d to afford [Ru]-CdC(Ph)C(dS)NPhCHPh (7d ). The structures of 6a and
7c were determined by single-crystal X-ray diffraction analysis.
In tr od u ction
with isothiocyanates RNCS to afford {Ru}CdC(Ph)C-
Metal acetylide complexes has been the focus of many
recent studies because of their applications in organo-
metallic1-4 and materials5-8 chemistry. A common reac-
tion of a metal acetylide is a [2 + 2] cycloaddition of
the triple bond with unsaturated organic substrates,9
such as CS2,10-12 (NC)2CdC(CF3)2, and (NC)2Cd
C(CN)2.13-15 Recently we reported16 a similar cycload-
dition reaction of the ruthenium acetylide complex
{Ru}CtCPh (1′, {Ru} ) (η5-C5H5)(PPh3)[P(OMe)3]Ru)
(dNR)S (2′). This cycloaddition was found to be revers-
ible, and in the absence of free isothiocyanate, the
acetylide complex was gradually regenerated. However,
in the presence of excess isothiocyanate, the six-
membered-ring complex {Ru}CdC(Ph)C(dS)N(R)C(d
NR)S, containing two isothiocyanate molecules, was
obtained. This indicates that the reversed cycloaddition
is a stepwise process. Formation of the six-membered-
ring complex was thus rationalized by opening of the
four-membered ring of 2′ via cleavage of the CR-S bond,
followed by coupling of a second isothiocyanate molecule.
Opening of the four-membered ring of 2′ could provide
a zwitterionic complex with the negative charge local-
ized at one of the heteroatoms (S and N), and a
subsequent alkylation reaction at the heteroatom site
could be a useful reaction. We therefore reacted alkyl
halides with the dppe analogue of the four-membered-
ring complex. Herein we report that these alkylation
reactions yield a number of vinylidene complexes.17-21
Subsequent deprotonation-induced-cyclization reactions
of these vinylidene complexes form neutral heterocy-
clopentenyl complexes.4,22
(1) Beck, W.; Niemer, B.; Wieser, M. Angew. Chem., Int. Ed. Engl.
1993, 32, 923.
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59.
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Chem. 1990, 30, 1.
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Organomet. Chem. 1998, 553, 417.
10.1021/om9901978 CCC: $18.00 © 1999 American Chemical Society
Publication on Web 07/30/1999

3446 Organometallics, Vol. 18, No. 17, 1999
Chang et al.
Sch em e 1
spectrum of the mixture, two triplet resonances at δ
341.5 (J C-P ) 18.2 Hz) and 342.2 (J C-P ) 17.7 Hz) are
assigned to CR’s of 3b and 4b, respectively, indicating
that both are vinylidene complexes.
Other vinylidene complexes [Ru]dCdC(Ph)C(dNPh)-
SCH2R+ (3c, R ) p-C6H4CN; 3d , R ) Ph) and [Ru]d
CdC(Ph)C(dS)N(Ph)CH2R+ (4c, R ) p-C6H4CN; 4d , R
) Ph) were similarly prepared as mixtures at room
temperature (3c:4c ) 1:2, total yield 87%; 3d :4d ) 6:5,
total yield 83%) by reacting 2 with organic bromides
(Scheme 1). Alkylation reactions take place both at the
N and the S atoms. Like 3a and 3b, complexes 3c, 4c,
3d , and 4d are all purple, air stable and thermally
stable, soluble in polar solvents such as CHCl3, CH2-
Cl2, acetone, and THF, and insoluble in ether and
hexane. Generally complexes 3 and 4 are not separable
by column chromatography. However, as described
below, pure complexes can be obtained indirectly.
Resu lts a n d Discu ssion
Syn th esis of Vin ylid en e Com p lexes. Treatment of
[Ru]CtCPh (1, [Ru] ) (η5-C5H5)(dppe)Ru, dppe ) Ph2-
PCH2CH2PPh2) with PhNCS in CH2Cl2 at room tem-
perature for 3 days affords the yellow [2 + 2] cycload-
Depr oton ation -In du ced Cyclization of Vin yliden e
Com p lex 3a . Treatment of 3a with n-Bu4NOH (1M in
MeOH) causes deprotonation of the methylene group,
followed by a cyclization reaction affording the neutral
dition product [Ru]-CdC(Ph)C(dNPh)S (2).23-26 On the
basis of the chemical reactivity of the bis(triphenylphos-
phine) analogue of 2,16 we believe that 2 exists in two
forms: a four-membered-ring structure and a zwitter-
ionic structure formed by cleavage of the CR-S bond of
the four-membered ring. In the zwitterionic form the
negative charge could be localized either at the S atom
or at the N atom, thus rendering these atoms nucleo-
philic. Indeed, treatment of 2 with ICH2CN affords the
air-stable cationic vinylidene complex {[Ru]dCdC(Ph)C-
(dNPh)SCH2CN}[I] (3a ) in 87% yield. The alkylation
is found to take place only at the S atom. The vinylidene
ligand of 3a was confirmed by the presence of a triplet
13C resonance at δ 340.7 with J C-P ) 13.4 Hz assignable
to CR. The 31P resonance of 3a appears as a singlet at δ
78.1 due to the fluxional behavior of the vinylidene
ligand. Interestingly, unlike other orange-red ruthenium
vinylidene complexes, 3a is purple.
complex [Ru]-CdC(Ph)C(dNPh)SCHCN (5a ) (Scheme
1). Protonation of 5a in CHCl3 with CF3COOH im-
mediately gives 3a in quantitative yield. In our attempt
to purify 5a by column chromatography, isomerization
to the 2-aminothiophene complex [Ru]-CdC(CN)SC-
(NHPh)dCPh (6a ) takes place. This conversion also
occurs in benzene at room temperature in 3 h. No
reaction was observed between complex 6a and electro-
philes such as CH3I, ICH2CN, and CH3COOH. The
transformation of 5a to 6a possibly proceeds via a
hydrogen shift process. When the reaction is carried out
at an appropriate concentration, single crystals of 6a
suitable for X-ray diffraction analysis can be obtained
directly. The 31P NMR spectrum of 5a shows two doublet
resonances at δ 72.30 and 69.12 with J P-P ) 29.76 Hz
due to the presence of an asymmetric carbon center in
the five-membered ring. The 31P NMR spectrum of 6a
displays a broad resonance at δ 67.55 at room temper-
ature which resolves into two doublets at δ 71.76 and
60.78 with J P-P ) 32.6 Hz at -80 °C, possibly due to
the hindered flipping of the pyramidal nitrogen atom.
Treatment of complex 2 with BrCH2CO2CH3 in CH2-
Cl2 affords a mixture of two cationic vinylidene com-
plexes, the S-alkylation product [Ru]dCdC(Ph)C(dNPh)-
SCH2CO2CH3+ (3b) and the N-alkylation product [Ru]d
+
CdC(Ph)C(dS)N(Ph)CH2CO2CH3 (4b) (Scheme 1), in
a ratio of 3:2 and with a total yield of 78%. The ratio of
3b to 4b depends on the reaction temperature, with 3b
favored at lower temperature. Under reflux conditions,
the 3b:4b ratio was found to be ca. 1:1. Complexes 3b
and 4b do not interconvert in solution and could not be
separated by chromatography. The 31P NMR spectrum
of the mixture displays two singlet resonances at δ 77.2
and 79.0 attributed to 3b and 4b, respectively. In the
1H NMR spectrum two resonances at δ 5.52 and 5.48
are assigned to the Cp groups of 3b and 4b, and
resonances at δ 3.45 and 3.43 are assigned to the CH2
groups of 3b and 4b , respectively. In the 13C NMR
The structure of 6a has been confirmed by a single-
crystal X-ray diffraction study. An ORTEP diagram is
shown in Figure 1, and selected bond distances and bond
angles are given in Table 1. This complex adopts a
distorted three-legged piano-stool geometry with the
P1-Ru-P2, P1-Ru-C1, and P2-Ru-C1 angles being
83.30(3), 116.96(11), and 99.26(9)°, respectively. The
metal center is coordinated to an sp2 C4 carbon of the
substituted 2-aminothiophene ligand. The Ru-C1 dis-
tance of 2.112(3) Å is typical for a Ru-C single bond,
and the C1-C2 distance of 1.445(5) Å is slightly longer
than that of a C-C double bond. Two other C-C bonds
(1.390(5) Å for C1-C4 and 1.387(5) Å for C2-C3)
indicate double bonds. The Ru-C1-C2 angle is 129.7-
(2)°, and the Ru-C1-C4 angle is 121.0(2)°, close to that
expected for C(sp2) hybridization. The C3-N1 distance
of 1.379(4) Å indicates a single bond. The bond distances
C4-S1 and C3-S1 of 1.755(4) and 1.724(4) Å, respec-
(23) Yih, K. H.; Lin, Y. C.; Cheng, M. C.; Wang, Y. J . Chem. Soc.,
Chem. Commun. 1993, 1380.
(24) Yih, K. H.; Lin, Y. C.; Cheng, M. C.; Wang, Y. J . Chem. Soc.,
Dalton Trans. 1995, 1305.
(25) Yih, K. H.; Yeh, S. C.; Lin, Y. C.; Lee, G. H.; Wang, Y.
Organometallics 1998, 17, 513.
(26) Chang, C. W.; Ting, P. C.; Lin, Y. C.; Lee, G. H.; Wang, Y. J .
Organomet. Chem. 1998, 553, 417.

Cyclization Reactions of Ru Vinylidene Complexes
Organometallics, Vol. 18, No. 17, 1999 3447
When the mixture of 3c and 4c was treated with
n-Bu4NOH, an immediate color change from purple to
yellow was observed. Interestingly, the deprotonation-
induced cyclization occurred for both 3c and 4c, giving
[Ru]-CdC(Ph)C(dNPh)SCH(p-C6H4CN) (5c) and [Ru]-
CdC(p-C6H4CN)SC(NHPh)dCPh (7c), respectively. The
31P NMR spectrum of the reaction mixture displays two
pairs of doublet resonances: one appears at δ 69.31 and
67.54 with J P-P ) 30.9 Hz, assignable to 5c, and the
other at δ 94.88 and 91.79 with J P-P ) 18.3 Hz,
assignable to 7c. Both patterns arise from the asym-
metric five-membered ring in 5c and 7c. These two
complexes could be separated by chromatography using
an alumina column. The 1H NMR spectrum of 5c shows
resonances at δ 3.77 and 3.58 assignable to Cp and CH
groups, respectively. Complex 5c is stable at -20 °C but
transforms to the corresponding 2-aminothiophene com-
plex 6c in solution at room temperature in 3 days.
Heating a solution of 5c accelerates this conversion. The
31P NMR spectrum of 6c displays an AX pattern at δ
F igu r e 1. ORTEP drawing of 6a with thermal ellipsoids
shown at the 30% probability level. For the dppe phenyl
groups, only the ipso carbons are shown.
Ta ble 1. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for Cp (d p p e)Ru -CdC(CN)SC(NHP h )dCP h
(6a )
1
72.15 and 66.40 with J P-P ) 28.8 Hz. In the H NMR
Ru-C1
Ru-P1
Ru-P2
S1-C1
S1-C4
N1-C3
2.112(3)
2.2747(10)
2.3103(9)
1.724(4)
1.755(4)
1.379(4)
C1-C2
C1-C4
C2-C3
C4-C5
N1-C12
N2-C5
1.445(5)
1.390(5)
1.387(4)
1.412(5)
1.402(5)
1.153(5)
spectrum of 6c, the Cp resonance appears at δ 3.47 and
the NH resonance at δ 5.84. Protonation of 5c with
excess CF3COOH yielded 3c.
Depr oton ation -In du ced Cyclization of Vin yliden e
Com p lex 4d . Treatment of a mixture of 3d and 4d with
P1-Ru-P2
P1-Ru-C1
P2-Ru-C1
Ru-C1-C4
Ru-C1-C2
C2-C1-C4
C1-C4-S1
C3-C2-C6
C5-C4-S1
83.30(3)
116.96(11)
99.26(9)
121.0(2)
129.7(2)
108.0(3)
115.0(3)
115.7(3)
115.2(3)
C4-S1-C3
S1-C3-C2
C1-C2-C3
C2-C3-N1
S1-C3-N1
C3-N1-C12
C4-C5-N2
C1-C4-C5
89.9(2)
112.2(3)
114.8(3)
124.5(3)
123.3(3)
131.8(3)
175.6(4)
129.3(3)
NaOMe affords directly [Ru]-CdC(Ph)C(dS)N(Ph)CH-
Ph (7d ), with no reaction occurring between 3d and
NaOMe. Complex 7d is unstable and can be separated
from 3d by extraction with hexane. Complex 7d was
also obtained by treatment of the mixture of 3d and 4d
with n-Bu4NOH.
Facile deprotonation shows the acidic nature of the
methylene protons of 3a -c, which may be ascribed
predominantly to the cationic character of the vinylidene
complexes. It is not known why 3d will not undergo
deprotonation. Generally deprotonation of 4c and 4d is
faster than that of 3. The resulting complexes 7c and
7d are yellowish solids and are soluble in CH2Cl2,
acetone, benzene, and ether. Complex 7c is stable in
acetone and in CHCl3 for 7 days, while 7d is relatively
less stable in solution and decomposes in CHCl3 in 8 h
at room temperature. Both 7c and 7d react with acids
such as CH3COOH and CF3COOH to give 4c and 4d ,
respectively. The spectroscopic data of both complexes
are similar.
tively, are typical of a C-S single bond.27 The C2-C3-
S1 angle is 112.2(3)°, and the C1-C4-S1 angle is
115.0(3)°. The C3-S1-C4 angle of 89.9(2)° is smaller
than that of a typical acyclic C-S-C angle.
Depr oton ation -In du ced Cyclization of Vin yliden e
Com p lexes 3b, 3c, a n d 4c. Treatment of a mixture of
3b and 4b in CH2Cl2 with NaOMe causes a color change
from purple to orange-yellow. The 31P NMR spectrum
of the orange-yellow solution displays two doublet
resonances at δ 73.4 and 64.5 with J P-P ) 28.8 Hz and
a singlet resonance at δ 94.0. The former set is at-
tributed to [Ru]-CdC(Ph)C(dNPh)SCH(CO2CH3) (5b)
and the latter to complex 2. The ratio of 5b to 2 is the
same as that of 3b to 4b, indicating that formations of
5b and 2 are derived from 3b and 4b, respectively.
Under the reaction conditions, the organic portion (CH2-
CO2CH3) of 4b was removed to give 2. Complexes 5b
and 2 were separated by column chromatography; 5b
decomposes at room temperature in 2 days in CH2Cl2.
Treatment of a mixture of 3b and 4b with DBU (1,8-
diazabicyclo[5,4,0]undecene) or n-Bu4NOH also yielded
a mixture of 5b and 2. Isomerization of 5b to the
2-aminothiophene complex 6b occurs in solution. As
with 6a , complex 6b has a broad 31P resonance at δ
65.10 at room temperature that at -40 °C resolves into
two doubletsat δ 69.73 and 58.66 with J P-P ) 32.2 Hz.
The molecular structure of 7c has been confirmed by
a single-crystal X-ray diffraction study. An ORTEP
diagram is shown in Figure 2, and selected bond
distances and bond angles are given in Table 2. The
metal center is coordinated to the sp2 carbon of the
substituted pyrrole-2-thione ligand. The P1-Ru-P2,
P1-Ru-C1, and P2-Ru-C1 angles are 83.75(4), 99.18-
(9), and 99.40(9)°, respectively. The Ru-C1 distance of
2.094(3) Å is typical for a Ru-C single bond, and the
C1-C2 distance of 1.368(4) Å indicates a C-C double
bond.27 Two other C-C bonds (1.522(4) Å for C1-C4
and 1.469(4) Å for C2-C3) are slightly different but are
still within the range of a single bond, as are the two
C-N bonds (1.479(4) Å for N1-C4 and 1.353(4) Å for
N1-C3). Of the analogous bonds (C1-C4 vs C2-C3 and
N1-C3 vs N1-C4) in the five-membered ring the one
closer to the metal center is generally slightly longer.
(27) Orpen, A. G.; Brammer, L.; Allen, F. H.; Kennard, O.; Watson,
D. G.; Taylor, R. J . Chem. Soc., Dalton Trans. 1989, S1.

3448 Organometallics, Vol. 18, No. 17, 1999
Chang et al.
Schlenk techniques. CH2Cl2 was distilled from CaH2, and
diethyl ether and THF were distilled from sodium diphenyl-
ketyl. All other solvents and reagents were of reagent grade
and were used as received. NMR spectra were recorded on
Bruker AC-200 and AM-300WB FT-NMR spectrometers at
room temperature (unless states otherwise) and are reported
in units of δ with residual protons in the solvents as a standard
(CDCl3, δ 7.24; C2D6O, δ 2.04). FAB mass spectra were
recorded on a J EOL SX-102A spectrometer. The complexes
[Ru]CtCPh (1, [Ru] ) (η5-C5H5)(dppe)Ru, dppe ) Ph2PCH2-
CH2PPh2) and [Ru]-CdC(Ph)C(dNPh)S (2) were prepared
according to the methods reported in the literature.16 Elemen-
tal analyses and X-ray diffraction studies were carried out at
the Regional Center of Analytical Instrument located at the
National Taiwan University.
Syn th esis of {[Ru ]dCdC(P h )S(dNP h )CH2CN}[I] (3a ).
To a CH2Cl2 (20.0 mL) solution of 2 (200 mg, 0.250 mmol) was
added ICH2CN (0.10 mL, 0.75 mmol) under nitrogen. The
resulting solution was stirred at room temperature for 2 h;
then the solvent was reduced to 5 mL. This mixture was slowly
added to 60 mL of vigorously stirred diethyl ether. The purple-
red precipitate thus formed was filtered and washed with
diethyl ether and hexane and dried under vacuum to give
{[Ru]dCdC(Ph)C(dNPh)SCH2CN}[I] (3a ; 214.7 mg, 0.222
mmol) in 89% yield. Spectroscopic data for 3a : 1H NMR
(CDCl3) δ 7.63-6.32 (m, 30H, Ph), 5.44 (s, 5H, Cp), 3.53 (s,
2H, CH2), 3.50-3.00 (m, 4H, CH2); 31P NMR (CDCl3) δ 77.55;
13C NMR (CDCl3) δ 340.7 (t, CR, J C-P ) 13.40 Hz), 148.6 (s,
SCN), 132.7-120.6 (Ph and Câ), 117.9 (CN), 93.2 (Cp), 28.1 (t,
PCH2, J C-P ) 25.6 Hz), 17.4 (s, CH2); MS (m/z, Ru102) 841.1
(M+ - I), 565.0 (M+ - CCPh - PhNCS - CH2CN). Anal. Calcd
for C48H41N2P2SRuI (967.80): C, 59.57; H, 4.27; N, 2.89.
Found: C, 59.23; H, 4.58; N, 3.12.
F igu r e 2. ORTEP drawing of 7c with thermal ellipsoids
shown at the 30% probability level. For the dppe phenyl
groups, only the ipso carbons are shown.
Ta ble 2. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for
Cp (d p p e)Ru -CdC(P h )C(dS)N(P h )CH(p-C6H4CN)
(7c)
Ru-C1
Ru-P1
Ru-P2
S1-C3
N1-C4
N1-C3
2.094(3)
2.3249(10)
2.2840(10)
1.664(3)
1.479(4)
1.379(4)
C1-C2
C1-C4
C2-C3
C4-C5
N1-C18
N2-C11
1.368(4)
1.522(4)
1.469(4)
1.520(5)
1.427(4)
1.144(5)
Syn th esis of {[Ru ]dCdC(P h )C(dNP h )SCH2CO2CH3}-
[Br ] (3b) a n d {[Ru ]dCdC(P h )C(dS)N(P h )CH2CO2CH3}-
[Br ] (4b). To a CH2Cl2 solution (20 mL) of 2 (200 mg, 0.250
mmol) was added BrCH2CO2CH3 (0.1 mL, 0.75 mmol). The
resulting solution was stirred at room temperature for 3 h.
1H and 31P NMR spectra of the mixture indicated formation
of the two major products 3b and 4b. Then the solvent was
reduced to 5 mL. This mixture was slowly added to 60 mL of
vigorously stirred diethyl ether. The purple-red precipitate was
filtered off, washed with diethyl ether and hexane, and dried
under vacuum to give a mixture of 3b and 4b (190.6 mg, 0.200
mmol) in a total yield of 80%. The 31P NMR spectrum of the
mixture displayed resonances attributed to 3b and 4b in a 3:2
ratio. Spectroscopic data for 3b: 1H NMR (CDCl3) δ 7.58-6.76
(m, 30H, Ph), 5.52 (s, 5H, Cp), 3.68 (s, 3H, OCH3), 3.45 (s, 2H,
CH2), 3.00-2.65 (m, 4H, PCH2CH2P); 31P NMR (CDCl3) δ
77.23; 13C NMR (CDCl3) δ 341.5 (t, CR, J C-P ) 18.2 Hz), 169.5
(CO), 145.6 (SCN), 141.9-121.6 (Ph and Câ), 94.5 (Cp), 53.7
(OCH3), 35.7 (CH2), 28.4 (t, PCH2, J C-P ) 23.2 Hz); MS (m/z,
Ru102) 874.1 (M+ - Br), 565.0 (M+ - CCPh - PhNCS - CH2-
CO2CH3). Spectroscopic data for 4b: 1H NMR (CDCl3) 7.54-
6.35 (m, 30H, Ph), 5.48 (s, 5H, Cp), 3.59 (s, 3H, OCH3), 3.43
(s, 2H, CH2), 2.80-2.35 (m, 4H, PCH2CH2P); 31P NMR (CDCl3)
δ 79.02; 13C NMR (CDCl3) 342.2 (t, CR, J C-P ) 17.7 Hz), 183.4
(CS), 168.1 (CO), 145.0-120.5 (Ph and Câ), 93.3 (Cp), 36.9
(CH2), 30.3 (t, PCH2, J C-P ) 22.1 Hz); MS (m/z, Ru102) 847.1
(M+ - Br), 565.0 (M+ - CCPh-PhNCS - CH2CO2CH3). Anal.
Calcd for C49H44NO2P2SRuBr (953.83): C, 61.70; H, 4.65; N,
1.47. Found for the mixture of 3b and 4b: C, 60.93; H, 4.55;
N, 1.32.
P1-Ru-P2
P1-Ru-C1
P2-Ru-C1
Ru-C1-C4
Ru-C1-C2
C2-C1-C4
C1-C4-N1
C3-C2-C1
C2-C3-N1
83.75(4)
99.18(9)
99.40(9)
121.1(2)
132.8(2)
105.7(3)
105.0(2)
111.4(3)
107.8(3)
C4-N1-C3
S1-C3-C2
C1-C2-C12
C2-C3-S1
S1-C3-N1
C3-N1-C18
C5-C4-N1
C1-C4-C5
109.9(3)
126.7(3)
130.2(3)
126.7(3)
125.6(3)
127.8(3)
110.4(3)
114.0(3)
This has also been observed in ruthenium cyclopropenyl
complexes. The bond distance of 1.664(3) Å for C3-S1
is typical of a C-S double bond.27
Con clu d in g Rem a r k s. Alkylations of the ruthenium
complex [Ru]-CdC(Ph)C(dNPh)S with various organic
halides XCH2R take place at both S and N atoms,
affording vinylidene complexes 3 and 4, respectively.
Deprotonation of these vinylidene complexes causes ring
closure, yielding metal complexes containing heterocy-
clic ligands. Using this method, neutral 2-aminothiophene
complexes [Ru]-CdC(R)SC(NHPh)dCPh (6a , R ) CN;
6b, R ) CO2CH3; 6c, R ) p-C6H4CN) and pyrrole-2-
thione complexes [Ru]-CdC(Ph)C(dS)N(Ph)CHR (7c,
R ) p-C6H4CN; 7d , R ) Ph) are all obtainable in
moderate to high yield. We are currently investigating
possible asymmetric induction by using the chiral
ruthenium metal center with different phosphine ligands.
Mixtures of the complexes {[Ru]dCdC(Ph)C(dNPh)SCH2-
(p-C6H4CN)}[Br] (3c) and {[Ru]dCdC(Ph)C(dS)N(Ph)CH2(p-
C6H4CN)}[Br] (4c) (3c:4c ) 1:2, 87% total yield) as well as
{[Ru]dCdC(Ph)C(dNPh)SCH2Ph}[Br] (3d ) and {[Ru]dCd
C(Ph)-C(dS)N(Ph)CH2Ph}[Br] (4d ) (3d :4d ) 6:5, 83% total
yield) were prepared using the same procedure as that for 3b
and 4b. Spectroscopic data for 3c: 1H NMR (CDCl3) δ 7.60-
Exp er im en ta l Section
Gen er a l P r oced u r es. All manipulations were performed
under nitrogen using vacuum-line, drybox, and standard

Cyclization Reactions of Ru Vinylidene Complexes
Organometallics, Vol. 18, No. 17, 1999 3449
6.18 (m, 34H, Ph), 5.39 (s, 5H, Cp), 3.33 (s, 2H, CH2), 3.20-
2.60 (m, 4H, PCH2CH2P); 31P NMR (CDCl3) δ 77.98; 13C NMR
(CDCl3) δ 354.7 (t, CR, J C-P ) 12.1 Hz), 182.5 (s, SCN), 140.4-
126.6 (Ph and Câ), 111.6 (CN), 93.6 (Cp), 30.9 (CH2), 28.1 (t,
PCH2, J C-P ) 23.7 Hz); MS (m/z, Ru102) 917.2 (M+ - Br), 565.1
(M+ - CCPh - PhNCS-CH2C6H4CN). Spectroscopic data for
4c: 1H NMR (CDCl3) δ 7.59-6.08 (m, 34H, Ph), 5.44 (s, 5H,
Cp), 3.38 (s, 2H, CH2), 3.40-2.80 (m, 4H, PCH2CH2P); 31P
NMR (CDCl3) δ 79.51; 13C NMR (CDCl3): δ 354.0 (t, CR, J C-P
) 15.2 Hz), 218.2 (s, CS), 135.8-126.4 (Ph and Câ), 92.5 (Cp),
1.66 (2m, 4H, PCH2CH2P); 31P NMR (-40 °C, CDCl3) δ 69.73,
58.66 (2d, J P-P ) 32.2 Hz); 13C NMR (CDCl3) δ 178.6 (CO),
165.4 (s, SCN), 143.2-116.3 (Ph and CR, Câ), 84.5 (Cp), 50.0
(CH3), 35.4 (t, PCH2, J C-P ) 18.2 Hz), 37.1 (t, PCH2, J C-P
20.1 Hz), 15.8 (s, CH); MS (m/z, Ru102) 873.0 (M+), 565.0 (M+
- CCPh - PhNCS - CHCO2CH3). Anal. Calcd for C49H43
)
-
NO2P2SRu (872.92): C, 67.20; H, 4.91; N, 1.60. Found: C,
66.85; H, 4.92; N, 1.61.
Syn th esis of [Ru ]-CdC(P h )C(dNP h )SCH(p-C6H4CN)
31.4 (CH2), 27.7 (t, PCH2, J C-P ) 23.2 Hz); MS (m/z, Ru102
)
(5c) a n d [Ru ]-CdC(P h )-C(dS)N(P h )CH(p-C6H4CN) (7c).
To a mixture of 3c and 4c (300 mg, 0.301 mmol, 3c: 4c ) 1:2)
in 15 mL of acetone was added n-Bu4NOH (1 mL, 1 M in
MeOH). The mixture was stirred at room temperature for 30
min to give a bright yellow solution, and then the volume of
the solution was reduced to ca. 3 mL. The residue was then
chromatographed on an alumina column. Diethyl ether eluted
compound 7c, and acetone eluted compound 5c. Removal of
the diethyl ether under vacuum give the solid product 7c
(119.4 mg, 0.130 mmol) in 65% yield (based on 4c). Removal
of the acetone gave an oily residue which was washed with 2
917.2 (M+ - Br), 565.1 (M+ - CCPh - PhNCS - CH2C6H4-
CN). Anal. Calcd for C54H45N2P2SRuBr (996.89): C, 65.06; H,
4.55; N, 2.81. Found for the mixture of 3c and 4c: C, 64.92;
H, 4.46; N, 2.72. Spectroscopic data for 3d : 1H NMR (CDCl3)
δ 7.75-6.25 (m, 35H, Ph), 5.40 (s, 5H, Cp), 4.46 (s, 2H, CH2),
3.10-3.40 (m, 4H, PCH2CH2P); 31P NMR (CDCl3) δ 78.12; 13
C
NMR (CDCl3) δ 184.0 (s, SCN), 145.3-121.2 (Ph and Câ), 93.7
(Cp), 28.9 (t, PCH2, J C-P ) 21.9 Hz), 15.9 (CH2); MS (m/z, Ru102
)
892.3 (M+ - Br), 565.1 (M+ - CCPh - PhNCS - CH2C6H5).
Spectroscopic data for 4d : 1H NMR (CDCl3) δ 7.59-6.06 (m,
35H, Ph), 5.33 (s, 5H, Cp), 3.30 (s, 2H, CH2), 3.10-3.40 (m,
4H, PCH2CH2P); 31P NMR (CDCl3) δ 81.11; 13C NMR (CDCl3)
δ 207.4 (s, CS), 143.1-120.3 (Ph and Câ), 92.8 (Cp), 29.2 (t,
PCH2, J C-P ) 23.4 Hz), 14.7 (CH2); MS (m/z, Ru102) 892.3 (M+
- Br), 565.1 (M+ - CCPh - PhNCS - CH2C6H5). Anal. Calcd
for C53H46NP2SRuBr (971.88): C, 65.49; H, 4.77; N, 1.44.
Found for the mixture of 3d and 4d : C, 65.74; H, 4.75; N, 1.51.
× 10 mL of hexane to give [Ru]CdC(Ph)C(dNPh)SCH(p-C6H4-
CN) (5c; 68.9 mg, 0.075 mmol) in 75% yield based on 3c.
Complex 5c in solution transformed to [Ru]CdC(p-C6H4CN)-
SC(NHPh)dCPh (6c) in 36 h at room temperature quantita-
tively. Spectroscopic data for 5c: 1H NMR (CDCl3) δ 7.50-
6.04 (m, 34H, Ph), 3.77 (s, 5H, Cp), 3.58 (s, CH), 2.85-2.50
(m, 4H, PCH2CH2P); 31P NMR (CDCl3) δ 69.31, 67.54 (2d, J P-P
) 30.85 Hz); 13C NMR (CDCl3) δ 162.7 (s, SCN), 142.6-120.7
(Ph and CR, Câ), 112.0 (CN), 84.2 (Cp), 30.3, 30.0 (2t, PCH2-
CH2P, J C-P ) 11.0 Hz), 28.3 (s, CH); MS (m/z, Ru102) 916.2
(M+), 565.1 (M+ - CCPh - PhNCS - CHC6H4CN). Spectro-
scopic data for 6c: 1H NMR (CDCl3) δ 7.43-6.35 (m, 34H, Ph),
5.84 (s, NH), 3.49 (s, 5H, Cp), 2.45-2.00 (m, 4H, PCH2CH2P);
31P NMR (CDCl3) δ 72.15, 66.40 (2d, J P-P ) 28.82 Hz); 13C
NMR (CDCl3) δ 161.4 (s, SCN), 145.4-125.1 (m, Ph and CR,
Syn th esis of [Ru ]-CdC(CN)SC(NHP h )dCP h (6a ). To
a solution of 3a (300 mg, 0.310 mmol) in 15 mL of acetone
was added n-Bu4NOH (1 mL, 1 M in MeOH). The mixture was
stirred at room temperature for 30 min to give a bright yellow
solution, and then the solvent was reduced to 3.0 mL. The
residue was chromatographed on a alumina column. The
yellow product was eluted with benzene. The solvent of the
eluate was reduced to ca. 1 mL, and 15 mL of hexane was
added to give yellow precipitates. The solid product was filtered
Câ), 111.5 (CN), 84.5 (Cp), 29.6, 29.2 (2t, PCH2CH2P, J C-P
)
and washed with 10 mL of hexane to give [Ru]-CdC(CN)SC-
10.5 Hz); MS (m/z, Ru102) 916.2 (M+), 565.1 (M+ - CCPh -
PhNCS - CHC6H4CN). Anal. Calcd for C54H44N2P2SRu
(915.98): C, 70.80; H, 4.84; N, 3.06. Found: C, 70.59; H, 4.48;
N, 3.12. Spectroscopic data for 7c: 1H NMR (CDCl3) δ 7.67-
6.08 (m, 34H, Ph), 3.94 (s, 5H, Cp), 3.09, 2.75 (2m, 5H, CH
(NHPh)dCPh (6a ; 177.0 mg, 0.211 mmol) in 68% yield.
Spectroscopic data for 6a : 1H NMR (CDCl3) δ 7.34-6.41 (m,
30H, Ph), 5.47 (s, NH), 3.92 (s, 5H, Cp), 2.13, 1.68 (2m, 4H,
CH2); 31P NMR (CDCl3) δ 67.55 (br); 31P NMR (acetone at -80
°C) δ 71.76, 60.79 (2d, J P-P ) 32.6 Hz); 13C NMR (CDCl3) δ
171.8 (s, SCN), 141.5-120.8 (Ph and CR, Câ), 116.1 (CN), 84.2
and PCH2CH2P); 31P NMR (CDCl3) δ 94.88, 91.79 (2d, J P-P
)
18.27 Hz); 13C NMR (CDCl3) δ 182.0 (CS), 143.4-119.8 (Ph
and CR, Câ), 108.6 (CN), 84.1 (Cp), 31.4, 30.9 (2t, PCH2CH2P,
J C-P ) 15.4 Hz), 28.7 (s, CH); MS (m/z, Ru102) 917.2 (M+ + 1),
565.0 (M+ - CCPh - PhNCS - CHC6H4CN). Anal. Calcd for
(Cp), 33.7, 33.3 (2t, PCH2, J C-P ) 22.6 Hz); MS (m/z, Ru102
)
840.0 (M+), 565.0 (M+ - CCPh - PhNCS - CHCN). Anal.
Calcd for C48H40N2P2SRu (839.89): C, 68.64; H, 4.80; N, 3.34.
Found: C, 69.02; H, 4.58; N, 3.27. The intermediate [Ru]-
C
54H44N2P2SRu (915.98): C, 70.80; H, 4.84; N, 3.06. Found:
C, 71.29; H, 4.92; N, 2.91.
CdC(Ph)S(dNPh)CHCN (5a ) was observed in about 10 min
when the reaction was monitored by NMR spectroscopy.
Complex 5a is unstable and readily converted to 6a when
passed through an alumina column at room temperature.
Spectroscopic data for 5a : 1H NMR (CDCl3) δ 7.81-6.28 (m,
30H, Ph), 4.65 (s, H, CHCN), 4.17 (s, 5H, Cp), 2.32, 2.08 (2m,
4H, CH2); 31P NMR (CDCl3) δ 72.30, 69.12 (2d, J P-P ) 29.8
Hz); MS (m/z, Ru102) 840.0 (M+), 565.0 (M+ - CCPh - PhNCS
- CHCN).
Complex 5b (48% based on 3b) was similarly prepared from
the reaction of n-Bu4NOH with a mixture of 3b and 4b. In
this reaction 4b decomposed to give 2. The products 5b and 2
were separated by column chromatography. When it was
dissolved in solution, complex 5b transformed to 6b in ca. 95%
yield. Spectroscopic data for 5b: 1H NMR (CDCl3) δ 7.82-
6.34 (m, 30H, Ph), 4.01 (s, 5H, Cp), 3.82 (s, 1H, CH), 3.27 (s,
3H, OCH3), 2.65-2.50 (2m, 4H, PCH2CH2P); 31P NMR (CDCl3)
δ 71.03, 69.98 (2d, J P-P ) 30.68 Hz); MS (m/z, Ru102) 873.0
(M+), 565.0 (M+ - CCPh - PhNCS - CHCO2CH3). Spectro-
scopic data for 6b: 1H NMR (CDCl3) δ 7.71-6.38 (m, 30H, Ph),
5.46 (s, 1H, NH), 3.92 (s, 5H, Cp), 3.07 (s, 3H, OCH3), 2.02,
Syn th esis of [Ru ]-CdC(P h )C(dS)N(P h )CHP h (7d ). To
a 20 mL CH2Cl2 solution of 3d and 4d (200 mg, 0.206 mmol,
3d :4d ) 6:5) was added NaOMe (55.6 mg, 1.03 mmol). The
mixture was stirred at room temperature for 30 min to give
an orange-yellow solution. The 31P NMR spectrum of the
solution indicated that 4d disappeared but 3d was inert. Then
the solvent was removed under vacuum and the residue was
extracted with 3 × 20 mL of hexane. After filtration, the
solvent was removed under vacuum to give the yellow product
[Ru]-CdC(Ph)C(dS)N(Ph)CHPh (7d ; 45.8 mg) in 55% yield
based on 4d . Spectroscopic data for 7d : 1H NMR (CDCl3) δ
7.78-6.15 (m, 35H, Ph), 4.87 (s, 5H, Cp), 2.91 (s, H, CH), 2.50-
2.15 (m, 4H, PCH2CH2P); 31P NMR (CDCl3) δ 92.61, 87.11 (2d,
J P-P ) 21.7 Hz); 13C NMR (CDCl3) δ 183.4 (SCN), 150.3,
146.1-121.8 (Ph, CR and Câ), 83.6 (Cp), 34.6 (s, CH), 31.4 (t,
PCH2CH2P, J C-P ) 23.4 Hz), 30.3 (t, PCH2CH2P, J C-P ) 24.5
Hz); MS (m/z, Ru102) 892.1 (M+ + 1), 565.0 (M+ - CCPh -
PhNCS - CHC6H5). Anal. Calcd for C53H45NP2SRu (890.98):
C, 71.44; H, 5.09; N, 1.57. Found: C, 72.02; H, 4.88; N, 1.52.

3450 Organometallics, Vol. 18, No. 17, 1999
Chang et al.
Ta ble 3. Cr ysta l a n d In ten sity Collection Da ta for
meter equipped with a CCD area detector and controlled by
SMART version 4 software. Data reduction was carried out
by SAINT version 4 and included profile analysis; this was
followed by absorption correction using the program SADABS.
Data were collected at 22 °C with Mo KR radiation. The
structures were determined by direct methods and refined
using the SHELXTL version 5 package. Hydrogen atoms were
introduced in ideal positions, riding on the carbon atom to
which they are bonded; each was refined with isotropic
temperature factors ranging from 20% to 50% greater than
that of the ridden atom. All other atoms were refined with
anisotropic thermal parameters. Pertinent crystal data are
listed in Table 3.
Cp (d p p e)Ru -CdC(CN)SC(NHP h )dC(P h ) (6a ) a n d
Cp (d p p e)Ru -CdC(P h )C(dS)N(P h )CH(p-C6H4CN)
(7c)
6a
7c
mol formula
space group
cryst syst
a, Å
b, Å
C
P21/n
48H40N2P2RuS
C54H44N2P2RuS
P21/n
monoclinic
12.5271(2)
18.9824(3)
16.9845(2)
101.6490(10)
3955.63(10)
4
monoclinic
14.6039(4)
18.9631(6)
16.7659(5)
97.503(1)
4603.3(2)
4
c, Å
â, deg
V, Å3
Z
Ack n ow led gm en t. We are grateful for support of
this work by the National Science Council, Taiwan,
Republic of China.
cryst dimens, mm3
2θ range, deg
indep/total no. of rflns
abs coeff, mm-1
max/min transmissn
0.15 × 0.10 × 0.10 0.20 × 0.20 × 0.15
1.63-26.38
8094/23 145
0.567
1.63-25.00
8110/19 473
0.494
0.8621/0.7560
R1 ) 0.0438
wR2 ) 0.0848
R1 ) 0.0850
wR2 ) 0.0996
0.398/-0.408
0.8622/0.6919
Su p p or tin g In for m a tion Ava ila ble: Details of the struc-
tural determination for complexes 6a and 7c, including tables
of crystal and intensity collection data, positional and aniso-
tropic thermal parameters, and all of the bond distances and
angles. This material is available free of charge via the
Internet at http://pubs.acs.org.
final R indices (I > 2σ(I)) R1 ) 0.0461
wR2 ) 0.0829
R indices (all data)
R1 ) 0.0853
wR2 ) 0.0969
0.389/-0.433
largest diff peak, e Å-3
X-r a y Cr ysta l Str u ctu r e An a lysis. The crystal structures
of 6a and 7c were determined with a Siemens P4 diffracto-
OM9901978