Reactions of ruthenium acetylide complexes with EtO2CNCS: Alkylation of the thione with dichloromethane

Article abstract of DOI:10.1021/om030341w

Treatment of the ruthenium acetylide complexes [M]C≡CPh (1a, [M] = [Ru] = Cp(Ph₂-PCH₂CH₂PPh₂)Ru; 1b, [M] = [Ru′] = Cp(PPh₃)[P(OMe)₃]Ru) with 1.1 equiv of EtO₂CN=C=S results in [2 + 2] cycloadditions yielding the four-membered-ring 2-iminothiete products 2a,b, respectively. Isomerization of complex 2a results in formation of 3a containing the six-membered-ring oxazinethione ligand. Alkylation of complex 3a by CH₂Cl₂ takes place at the thione sulfur to give 4a, which loses ethyl chloride, yielding the new six-membered-ring [1,3]-oxazin-2-one complex 5a. Further alkylation of 3a by the chloromethyl group of 5a affords the dinuclear complex 6a with two oxazin-2-one ligands bridged by a methylene group. Structures of 2b, 3a, 5a and 6a have been determined by single-crystal X-ray diffraction analysis.

Full text of DOI:10.1021/om030341w

Organometallics 2003, 22, 3891-3897
3891
Rea ction s of Ru th en iu m Acetylid e Com p lexes w ith
EtO2CNCS: Alk yla tion of th e Th ion e w ith
Dich lor om eth a n e
Chao-Wan Chang,† Ying-Chih Lin,*,‡ Gene-Hsiang Lee,‡ and Yu Wang‡
National University Preparatory School for Overseas Chinese Students, Linkou,
Taipei Hsien 244, Taiwan, Republic of China, and Department of Chemistry,
National Taiwan University, Taipei 106, Taiwan, Republic of China
Received May 8, 2003
Treatment of the ruthenium acetylide complexes [M]CtCPh (1a , [M] ) [Ru] ) Cp(Ph2-
PCH2CH2PPh2)Ru; 1b, [M] ) [Ru′] ) Cp(PPh3)[P(OMe)3]Ru) with 1.1 equiv of EtO2CNd
CdS results in [2 + 2] cycloadditions yielding the four-membered-ring 2-iminothiete products
2a ,b, respectively. Isomerization of complex 2a results in formation of 3a containing the
six-membered-ring oxazinethione ligand. Alkylation of complex 3a by CH2Cl2 takes place at
the thione sulfur to give 4a , which loses ethyl chloride, yielding the new six-membered-ring
[1,3]-oxazin-2-one complex 5a . Further alkylation of 3a by the chloromethyl group of 5a
affords the dinuclear complex 6a with two oxazin-2-one ligands bridged by a methylene group.
Structures of 2b, 3a , 5a and 6a have been determined by single-crystal X-ray diffraction
analysis.
In tr od u ction
In investigating chemical properties of acetylide
complexes of ruthenium, we previously reported reac-
tions of isocyanate and isothiocyanate with two such
ruthenium complexes.8 The cycloaddition reaction of an
isothiocyanate molecule with the ruthenium acetylide
formed an unstable four-membered-ring 2-iminothiete
complex. During purification, gradual loss of the isothio-
cyanate portion occurred in solution, giving back the
acetylide complex. In the presence of excess isothiocy-
anates, expansion of the 2-iminothiete rings by coupling
of the second isothiocyanate molecule generated com-
plexes with a six-membered-ring 2-imino-1,3-thiazine-
4-thione ligand. In this paper we report reactions of
ruthenium acetylide complexes with EtO2CNCS, a more
reactive isothiocyanate. As expected, in the initial stage,
cycloaddition of the CdS bond of EtO2CNCS to the
acetylide ligand gives the anticipated complex with the
four-membered thiete ring containing an imino ester
group. However, for the product with a dppe ligand,
isomerization of this thiete ring generates a six-
membered oxazine ring with a thione group, at which
alkylation by CH2Cl2 take place readily. Herein we
report the synthesis and characterization of these thiete
and oxazine complexes. An unusual alkylation of the
thione group by using CH2Cl2 is also described.
The synthesis and reactivity of metal acetylide com-
plexes have been the focus of several recent works, due
to their applications in organometallic1 and material2
chemistry. The coordinated acetylide ligand is reactive
toward electrophiles, undergoing either alkylation or
protonation at Câ to give stable vinylidene complexes.
Cycloadditions of metal acetylide with isocyanates take
place in several Ni(0) complexes.3 The other common
reaction observed for the acetylide is the [2 + 2]
cycloadditions of the triple bond with unsaturated
organic substrates.4 Cycloadditions of organic substrates
such as CS2,5 (NC)2CdC(CF3)2, (NC)2CdC(CN)2,6 and
Ph2CdCdO7 to the acetylide ligand in various metal
complexes have been reported.
† National University Preparatory School for Overseas Chinese
Students.
‡ National Taiwan University.
(1) (a) Beck, W.; Niemer, B.; Wieser, M. Angew. Chem., Int. Ed. Engl.
1993, 32, 923. (b) Hegedus, L. S. In Organometallics in Synthesis;
Schlosser, M., Ed.; Wiley: New York, 1994; p 383. (c) Bartik, T.; Bartik,
B.; Brady, M.; Dembinski, R.; Gladysz, J . A. Angew. Chem. 1996, 3S,
414. (d) Ting, P. C.; Lin, Y. C.; Lee, G. H.; Cheng, M. C.; Wang, Y. J .
Am. Chem. Soc. 1996, 118, 6433.
(2) (a) Myers, L. K.; Langhoff, C.; Thompson, M. B. J . Am. Chem.
Soc. 1992, 114, 7560. (b) Kaharu, T.; Matsubara, H.; Takahashi, S. J .
Mater. Chem. 1992, 2, 43. (c) Lavastre, O.; Even, M.; Dixneuf, P. H.;
Pacreau, A.; Vairon, J . P. Organometallics 1996, 15, 1530. (d) Wu, I.
Y.; Lin, J . T.; Luo, J .; Sun, S. S.; Lee, C. S.; Lin, K. J .; Tsai, C.; Hsu,
C. C.; Lin, J . L. Organometallics 1997, 16, 2038.
Resu lts a n d Discu ssion
(3) Hoberg, H.; Oster, B. W. J . Organomet. Chem. 1983, 252, 359.
(4) Bruce, M. I.; Hambley, T. W.; Leddell, M. J .; Snow, M. R.;
Swincer, A. G.; Tiekink, R. T. Organometallics 1990, 9, 96.
(5) (a) Selegue, J . P. J . Am. Chem. Soc. 1982, 104, 119. (b)
Birdwhistell, K. R.; Templeton, J . L. Organometallics 1985, 4, 2062.
(c) Selegue, J . P.; Young, B. A.; Logan, S. L. Organometallics 1991,
10, 1972.
(6) (a) Davison, A.; Solar, J . P. J . Organomet. Chem. 1979, 166, C13.
(b) Bruce, M. I.; Hambley, T. W.; Snow, M. R.; Swincer, A. G.
Organometallics 1985, 4, 501. (c) Barrette, A. G. M.; Carpenter, N. E.;
Mortier, J .; Sabat, M. Organometallics 1990, 9, 151.
Rea ction s of Ru th en iu m Acetylid e Com p lexes
w ith EtO2CNCS. Treatment of [Ru]CtCPh (1a , [Ru]
) Cp(dppe)Ru) with 1.1 equiv of EtO2CNdCdS in
CHCl3 at room temperature results in a color change of
the solution from yellow to orange in 10 min. The
reaction is complete in 1 h and affords the orange
(7) Hong, P.; Sonogashira, K.; Hagihara, N. J . Organomet. Chem.
1981, 219, 363.
(8) Chang, C. W.; Lin, Y. C.; Lee, G. H.; Huang, S. L.; Wang, Y.
Organometallics 1998, 17, 2534.
10.1021/om030341w CCC: $25.00 © 2003 American Chemical Society
Publication on Web 08/15/2003

3892 Organometallics, Vol. 22, No. 19, 2003
Chang et al.
F igu r e 1. ORTEP drawing of 2b. Thermal ellipsoids are drawn at the 50% probability level.
phite and phosphine ligands, and the carbon atom (C1)
of the organic ligand. The four-membered ring formed
by [2 + 2] cycloaddition is essentially planar, with a C1-
C2 distance of 1.373(7) Å, typical of a C-C double bond.
The bond distances for C1-S1 and C3-S1 (1.879(4) and
1.800(6) Å, respectively) are both typical of C-S single
bonds.8,10 The C3dN4 bond distance of 1.277(6) Å
confirms the presence of an imino group. The two
ruthenium-phosphorus bonds in 2b are Ru-P1 )
2.2312(13) Å and Ru-P2 ) 2.3276(13) Å, with the
shorter distance belonging to the phosphite ligand. The
S1-C1-C2, C1-C2-C3, and C2-C3-S1 bond angles
of 92.8(3), 100.8(4), and 94.1(4)°, respectively, are much
smaller than an sp2 hybridization bond angle, and the
C1-S1-C3 bond angle of 72.0(2)° is smaller than a
typical bond angle for a four-membered ring. Organic
compounds containing similar four-membered rings
with an imino group have been observed as stable
products from the phosphine-induced elimination of a
sulfur atom from some l,2-dithio-3-imines.11 The struc-
tural features of the 2-imino-2H-thiete portion, includ-
ing the dihedral angle between the planes of the four-
membered ring and the phenyl substituent in the imino
groups, are similar to those in 2b.
Isom er iza tion of 2a . From the reaction of 1a with
1.1 equiv of EtO2CNCS for 1 day in CHCl3, a mixture
containing 2a and 3a in a 1:3 ratio was isolated. Single
crystals of 3a suitable for X-ray diffraction analysis are
obtained by recrystallization of the mixture from CHCl3/
n-pentane (1:3). Pure complex 2a in CHCl3 also under-
goes isomerization to yield a mixture of 2a and 3a in a
similar ratio. 31P NMR resonances of complexes 2a and
3a are almost identical (at δ 96.72 and 96.03), but two
ethyl groups are distinguishable in their 1H NMR
spectra. Resonances of the ethyl group of 3a appear at
δ 3.79 and 0.88 with J H-H ) 7.05 Hz. The FAB mass
spectrum of 3a displays a parent peak and fragmenta-
tion peaks comparable to that of 2a . The structure of
3a has been determined by single crystal X-ray diffrac-
2-iminothiete product [Ru]CdC(Ph)C(dNCO2Et)S (2a )
in 92% isolated yield. We reported earlier8 that the
optimized conditions for the reaction of 1a with PhNCS,
yielding a similar product, required a 10-fold excess of
PhNCS and a long reaction time (3 days). However, the
reaction of 1a with EtO2CNCS needs only a slight excess
of isothiocyanate and is much faster. A [2 + 2] cycload-
dition of the CtC triple bond of 1a to the CdS double
bond of EtO2CNCS satisfactorily accounts for the for-
mation of 2a . The 31P NMR spectrum of 2a displays a
broad singlet resonance at δ 96.72 assigned to the dppe
ligand. The FAB mass spectrum displays a parent peak
at m/z 798.2 (M+ + 1), consistent with the formula of
2a . Cycloaddition of a CtC bond of iron acetylide to CS2
was found to yield 2H-thiete-2-thione (â-dithiolactone).5
A similar process has been proposed in the first stage
of the reaction of alkyne with CS2, giving a 2H-thiete-
2-thione intermediate which was characterized spec-
troscopically.5 Reaction of phosphenium complexes with
isocyanates via a [2 + 2] addition of the NdC bond to
give the four-membered phosphametallacycles has also
been reported.9
Similarly, treatment of the complex [Ru′]CtCPh (1b,
[Ru′] ) Cp(PPh3)[P(OMe)3]Ru) with 1.1 equiv of EtO2-
CNCS in CH2Cl2 at room temperature results in forma-
tion of the thiete product [Ru′]CdC(Ph)C(dNCO2Et)S
(2b) in 83% yield. In the 31P NMR spectrum, two doublet
resonances at δ 152.72 and 56.92 with J P-P ) 67.1 Hz
are assigned to the P(OMe)3 and PPh3 ligands, respec-
tively. The parent peak in the FAB mass spectrum is
consistent with the formula. Complex 2b was recrystal-
lized from a mixture of CH2Cl2 and hexane (1:3) at 5
°C, and the molecular structure was determined by
single-crystal X-ray diffraction analysis; an ORTEP
drawing is shown in Figure 1. Crystal and intensity
collection data are given in Table 1, and selected bond
distances and angles are listed in Table 2. The coordi-
nation sphere of the ruthenium atom contains a η5-
cyclopentadienyl ring, two phosphorus atoms of phos-
(10) Frank, G. W.; Degen, P. J . Acta Crystallogr., Sect. B 1973, B29,
1815.
(9) Malisch, W.; Hahner, C.; Gru¨n, J .; Reising, J .; Goddard, R.;
(11) Goerdeler, J .; Yunis, M.; Puff, H.; Roloff, A. Chem. Ber. 1986,
119, 162.
Kru¨ger, C. Inorg. Chim. Acta 1996, 244, 147.

Reactions of Ru Acetylide Complexes with EtO2CNCS
Organometallics, Vol. 22, No. 19, 2003 3893
Ta ble 1. Cr ysta l a n d In ten sity Collection Da ta for Com p ou n d s 2b, 3a , 5a , a n d 6a
c
c
2b
3a ‚CHCl3
5a ‚CH3COCH3
6a ‚CH3OHc
formula
fw
C
38H39NO5P2RuS
C44H40Cl3NO2P2RuS
916.19
C45H42ClNO3P2RuS
875.32
C84H74N2O5P4Ru2S2
1581.59
784.77
temp, K
cryst syst
space group
a, Å
b, Å
c, Å
295(2)
triclinic
P1h
150(1)
triclinic
P1h
295(2)
monoclinic
P21/c
12.2203(1)
18.8528(2)
18.4824(1)
90
103.031(1)
90
4148.45(6)
4
1.401
0.610
1800
295(2)
triclinic
P1h
10.8554(2)
12.1181(2)
14.3910(1)
88.109(1)
79.027(1)
82.301(1)
1841.67(5)
2
14.1727(5)
15.6797(5)
18.5534(6)
94.6404(10)
98.1618(8)
90.4884(8)
4067.0(2)
4
14.82850(10)
16.0216(2)
16.63470(10)
98.2560(10)
107.4950(10)
91.1730(10)
3721.65(6)
2
R, deg
â, deg
γ, deg
V, Å3
Z
d(calcd), Mg/m3
abs coeff, mm-1
F(000)
1.415
0.612
808
1.496
0.752
1872
1.411
0.602
1624
no. of rflns collected
no. of indep rflns
GOFa on F2
R (I > 2σ(I))b
20 610
7509 (Rint ) 0.0611)
1.028
R1 ) 0.0582
wR2 ) 0.1229
R1 ) 0.0988
wR2 ) 0.1415
1.056, -0.819
54 419
18671 (Rint ) 0.0614)
1.113
R1 ) 0.0636
wR2 ) 0.1294
R1 ) 0.0859
wR2 ) 0.1404
0.945, -0.751
28 120
8481 (Rint ) 0.0315)
1.088
R1 ) 0.0427
wR2 ) 0.1141
R1 ) 0.0535
wR2 ) 0.1221
1.066, -0.593
40 442
13105 (Rint ) 0.0634)
1.014
R1 ) 0.0406
wR2 ) 0.0809
R1 ) 0.0754
wR2 ) 0.0915
0.591, -0.400
R (all data)
peak, hole, e Å-3
GOF ) [∑[w(Fo - Fc2)2]/(n - p)]1/2, where n and p denote the number of data and parameters. R1 ) (∑||Fo| - |Fc||)/∑|Fo| and wR2
a
2
b
) [∑[w(Fo - Fc2)2]/∑[w(Fo2)2]]1/2 where w ) 1/[σ2(Fo2)+ (aP)2 + bP] and P ) [Fo + 2Fc2]/3. c The solvent was found to incorporate with
the crystals.
2
2
Ta ble 2. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) of
Cp (P P h 3)[P (OMe)3]Ru CdC(P h )C(dNCO2Et)S (2b)
Ru-P(1)
2.2312(13)
2.012(5)
1.800(6)
1.158(10)
1.373(7)
1.277(6)
1.473(9)
Ru-P(2)
2.3276(13)
1.879(4)
1.271(9)
1.463(8)
1.433(6)
1.407(8)
Ru-C(1)
S(1)-C(1)
O(4)-C(5)
O(5)-C(6)
C(2)-C(3)
N(4)-C(5)
S(1)-C(3)
O(5)-C(5)
C(1)-C(2)
C(3)-N(4)
C(6)-C(7)
P(1)-Ru-P(2)
C(1)-Ru-P(1)
C(5)-O(5)-C(6)
Ru-C(1)-S(1)
C(2)-C(3)-S(1)
O(4)-C(5)-O(5)
O(5)-C(5)-N(4)
92.37(5)
90.17(13)
122.0(10)
129.0(3)
94.1(4)
Ru-C(1)-C(2)
C(3)-S(1)-C(1)
C(2)-C(1)-S(1)
C(1)-C(2)-C(3)
C(3)-N(4)-C(5)
O(4)-C(5)-N(4)
138.2(3)
72.0(2)
92.8(3)
100.8(4)
120.1(6)
123.3(7)
118.8(8)
116.8(8)
tion analysis. An ORTEP drawing is shown in Figure
2. Selected bond distances and angles are listed in Table
3. Two independent molecules, which are essentially
very similar, are observed in the unit cell of the crystal,
along with two solvated chloroform molecules. The six-
membered oxazinethione ring is basically planar, with
a C1-C2 distance of 1.387(6) Å, typical of a C-C double
bond. The bond distance for C3-S1 (1.684(4) Å) is
typical of a CdS double bond. The C4dN1 bond distance
of 1.279(5) Å differs from the neighboring C3-N1
distance of 1.388(5) Å, indicating localization of double
bonds in the six-membered ring.
The isomerization could involve opening of the four-
membered 2-iminothiete ring to form zwitterionic vi-
nylidene with the anionic charge delocalized between
the sulfur atom and the oxygen atom of the carbonyl
group (see Scheme 1). A more electronegative oxygen
atom makes 3a , with the six-membered oxazine ring
containing a thione group, the predominant species after
ring closure. Even though EtO2CNCS is known to
undergo nucleophilic attack at the isothiocyanate C
atom,12 the fact that no 3a is observed in the early stage
of the reaction of 1a with EtO2CNCS indicates that
F igu r e 2. ORTEP drawing of 3a ‚CHCl3. Thermal el-
lipsoids are drawn at the 50% probability level. Chloroform
molecules are omitted for clarity.
formation of 2a may involve a fast concerted [2 + 2]
cycloaddition, not via the zwitterionic vinylidene inter-
mediate. Transformation between 2a and 3a is a slow
step. It takes 1 day to establish the equilibrium of 2a
and 3a in a 1:3 ratio.
Alk yla tion Rea ction a t th e Th ion e Su lfu r of th e
Oxa zin e Com p lex. The reaction of complex 2a with
CH2Cl2 for 4 days gave the six-membered oxazine
complex [Ru]CdC(Ph)C(SCH2Cl)NC(dO)O (5a ) in 87%
isolated yield. The reaction of 3a with CH2Cl2 takes 3
days to give 5a in high yield. Also direct reaction of 1a
with a 5-fold excess of EtO2CNCS in CH2Cl2 at room
(12) (a) Kurzer, F.; Secker, J . L. J . Heterocycl. Chem. 1989, 26, 355.
(b) Molina, P.; Alajarin, M.; Lopez-Lazaro, A. Tetrahedron 1991, 47,
6747. (c) Molina, P.; Alajarin, M.; Arques, A.; Benzal, R. J . Chem. Soc.,
Perkin Trans. 1 1982, 351. (d) Garmaise, D. L.; Schwartz, R.; Mckay,
A. F. J . Am. Chem. Soc. 1958, 80, 3332.

3894 Organometallics, Vol. 22, No. 19, 2003
Chang et al.
Ta ble 3. Selected Bon d Dista n ces (Å) a n d An gles
Sch em e 1
(d eg) of Cp (d p p e)Ru CdC(P h )C(dS)NdC(OEt)O (3a )
Ru(1)-P(1)
Ru(1)-P(2)
O(1)-C(1)
O(2)-C(4)
N(1)-C(4)
C(1)-C(2)
2.2756(11)
2.2619(12)
1.420(5)
1.323(5)
1.279(5)
1.387(6)
Ru(1)-C(1)
S(1)-C(3)
O(1)-C(4)
O(2)-C(11)
N(1)-C(3)
C(2)-C(3)
2.047(4)
1.684(4)
1.323(5)
1.443(6)
1.388(5)
1.436(6)
C(1)-Ru(1)-P(1)
P(1)-Ru(1)-P(2)
C(4)-O(2)-C(11) 116.3(4)
C(2)-C(1)-Ru(1) 136.5(3)
O(1)-C(1)-Ru(1) 110.6(3)
N(1)-C(3)-C(2)
C(2)-C(3)-S(1)
N(1)-C(4)-O(2)
87.69(12) C(1)-Ru(1)-P(2)
89.36(12)
122.1(3)
115.8(4)
112.9(3)
121.7(4)
116.5(3)
127.4(4)
107.9(4)
84.59(4)
C(4)-O(1)-C(1)
C(4)-N(1)-C(3)
C(2)-C(1)-O(1)
C(1)-C(2)-C(3)
N(1)-C(3)-S(1)
N(1)-C(4)-O(1)
O(1)-C(4)-O(2)
120.1(4)
123.4(3)
124.7(4)
temperature for 7 days afforded 5a with lower overall
yield. The reaction carried out in CHCl3 yielded no
alkylation product. Characterization of 5a by spectro-
scopic methods and by structure determination indicates
that an unusual alkylation by CH2Cl2 takes place at the
thione sulfur atom. Resonances at δ 4.86 and 43.1 in
the 1H and 13C NMR spectra, respectively, of 5a are
assigned to the chloromethyl group on the sulfur atom.
The reaction also yielded volatile ethyl chloride, ob-
served by the 1H NMR spectrum of the reaction mixture.
Complex 5a was recrystallized from a mixture of acetone
and hexane (1:3) at 5 °C, and the molecular structure
was determined by single-crystal X-ray diffraction
analysis; an ORTEP drawing of 5a is shown in Figure
3, and selected bond distances and angles are listed in
Table 4. The bond distance of Ru-C(1) (2.040(3) Å) is
typical of a Ru-C single bond. The C(1)-C(2), N(1)-
C(9), and N(1)-C(10) bond lengths of 1.399(4), 1.355-
(5), and 1.324(4) Å, respectively, all displaying partial
double-bond character, are indicative of several reso-
nance contributions. The bond distance of O(2)-C(9) is
1.214(4) Å, comparable to an idealized CdO double
bond. The bond distances of O(1)-C(9) (1.385(4) Å) and
O(1)-C(1) (1.398(4) Å) are both typical of a C-O single
bond. The heterocyclic six-membered oxazine ring is
essentially planar. The bond angle S(1)-C(11)-Cl(1) of
the thiochloromethyl group is 114.4(3)°, close to that
expected for C(sp3) hybridization. The bond distances
F igu r e 3. ORTEP drawing of 5a ‚CH3COCH3. Thermal ellipsoids are drawn at the 50% probability level. Acetone molecules
are omitted for clarity.

Reactions of Ru Acetylide Complexes with EtO2CNCS
Organometallics, Vol. 22, No. 19, 2003 3895
F igu r e 4. ORTEP drawing of 6a ‚CH3OH. Thermal ellipsoids are drawn at the 50% probability level. Methanol molecules
are omitted for clarity. For the phenyl groups on dppe, only the ipso carbons are shown.
Ta ble 4. Selected Bon d Dista n ces (Å) a n d An gles
peared at δ 98.65. The intermediate 4a could possibly
be a cationic alkylation product before loss of EtCl (see
Scheme 1). Formation of 5a is thus considered to
proceed via a stepwise process.
Formation of 5a from 2a is concentration dependent;
namely, 5a is the only product (87% yield) at the
concentration of 5 mM of 2a in CH2Cl2, but at higher
concentration (25 mM), in addition to 5a (ca. 50% yield),
(d eg) of Cp (d p p e)Ru CdC(P h )C(SCH2Cl)NC(dO)O
(5a )
Ru-P(1)
2.2694(9)
2.2774(87)
1.781(5)
1.385(4)
1.398(4)
1.324(4)
1.408(5)
Ru-C(1)
2.040(3)
1.783(4)
1.764(6)
1.214(4)
1.355(5)
1.399(4)
Ru-P(2)
S(1)-C(10)
Cl(1)-C(11)
O(2)-C(9)
N(1)-C(9)
C(1)-C(2)
S(1)-C(11)
O(1)-C(9)
O(1)-C(1)
N(1)-C(10)
C(2)-C(10)
the new product [Ru]CdC(Ph)C(S-)NC(dO)O]2CH2 (6a )
formed in 33% yield. Complex 6a , insoluble in acetone,
is readily separated from 5a by washing the mixture
with acetone. The NMR spectra of complexes 5a and
6a are very similar. The FAB mass spectrum of 6a
displays a parent peak at m/z 1551.0. Complex 6a is a
stable yellow compound, soluble in polar solvents such
as CH2Cl2 and CHCl3, moderately soluble in acetone,
acetonitrile, and methanol, and insoluble in diethyl
ether and hexane. Formation of 6a could occur by a
nucleophilic attack of the thione sulfur atom of 3a at
the chloromethyl group of 5a , followed by elimination
of EtCl. Recently Grapperhaus et al. reported a similar
reaction that CH2Cl2 alkylated a trithiolato-ruthenium
complex to yield a methylene-bridged thioether core.15
Recrystallization of 6a by slow evaporation of a CH2-
Cl2/MeOH solution at room temperature affords yellow
crystals. The structure of 6a has been determined by
single-crystal X-ray diffraction analysis. An ORTEP
drawing is shown in Figure 4, and selected bond
distances and angles are listed in Table 5. The bond
distances of both Ru(1)-C(1) (2.041(3) Å) and Ru(2)-
C(11) (2.041(3) Å) are typical of a Ru-C single bond.
The C(1)-C(4) and C(11)-C(14) bond lengths of 1.396-
(4) and 1.395(4) Å indicate double bonds. The C(3)-N(1),
C(13)-N(2), C(2)-N(1), and C(12)-N(2) bond lengths
of 1.330(4), 1.328(4), 1.343(4), and 1.357(4) Å, respec-
tively, all display partial double-bond character. The
bond distance of C(2)-O(2) is 1.221(4) Å, comparable
to an idealized C-O double bond. Both heterocyclic six-
membered-ring ligands are essentially coplanar. The
methylene-bridged bond angle S(2)-C-S(1) (114.77-
(18)°) is close to S(2)-C(11)-Cl(1) in 5a . The bond
distances of S(1)-C and S(2)-C (1.799(3) and 1.795(3)
Å, respectively) are in the range of a normal C-S single
bond. Ligand-based reactivity of metal-coordinated thi-
olates has been known in the literature, and alkylation,
C(1)-Ru-P(1)
P(1)-Ru-P(2)
86.20(9) C(1)-Ru-P(2)
84.24(3) C(9)-O(1)-C(1)
90.45(9)
126.2(3)
113.0(3)
112.9(2)
123.1(3)
115.6(3)
119.1(3)
116.8(3)
C(10)-N(1)-C(9) 116.1(3)
C(2)-C(1)-O(1)
O(1)-C(1)-Ru
C(2)-C(1)-Ru
133.9(2)
118.1(3)
118.8(3)
125.2(3)
C(1)-C(2)-C(10)
C(10)-C(2)-C(3)
O(2)-C(9)-N(1)
C(1)-C(2)-C(3)
O(2)-C(9)-O(1)
N(1)-C(9)-O(1)
N(1)-C(10)-S(1)
N(1)-C(10)-C(2) 127.1(3)
C(2)-C(10)-S(1) 116.2(2)
Cl(1)-C(11)-S(1) 114.4(3)
S(1)-C(11) and C(11)-Cl(1) of 1.781(5) and 1.764(6) Å,
respectively, are in the range of normal C-S and C-Cl
single bonds.
Alkylation of the six-membered thiazine thione ring
is known13 to take place at the thione sulfur atom. It is
therefore not surprising to see the formation of 5a from
3a or from 2a in CH2Cl2. Formation of 5a from 2a could
be induced14 initially by isomerization of 2a to 3a
followed by nucleophilic attack of the thione sulfur at
CH2Cl2 (Scheme 1). This unusual alkylation at the
sulfur atom stimulates us to investigate this reaction
in detail. The reaction of 2a with CH2Cl2 reveals some
interesting insight into the process. When the reaction
is monitored by 31P NMR spectroscopy, an additional
intermediate is observed. Within 1 day, the 31P reso-
nance at δ 96.72 of 2a diminished while a resonance at
δ 96.03 attributed to 3a appeared. This was followed
by the emergence of a new resonance at δ 92.7 assign-
able to the intermediate 4a . After two more days, the
31P resonance attributed to the final product 5a ap-
(13) (a) Chang, C. W.; Lin, Y. C.; Lee, G. H.; Huang, S. L.; Wang, Y.
J . Organomet. Chem. 2002, 660, 127. (b) Schatz, J .; Sauer, J .
Tetrahedron Lett. 1994, 35, 4767. (c) Kakioka, Y.; Uebori, S.; Tsuno,
M.; Taniguchi, Y.; Takaki, K.; Fujiwara, Y. J . Org. Chem. 1996, 61,
372.
(14) (a) Mukerjee, A. K.; Ashare, R. Chem. Rev. 1991, 91, 1. (b)
Adams, R. D.; Huang, M. Chem. Ber. 1996, 129, 485. (c) Adams, R. D.;
Chen, L.; Wu, W. Organometallics 1993, 12, 3812. (d) Adams, R. D.;
Huang, M. Organometallics 1996, 15, 2125. (e) Cowie, M.; Dwight, S.
K. J . Organomet. Chem. 1980, 198, C20. (f) Werner, H. Coord. Chem.
Rev. 1982, 43, 165.
(15) (a) Grapperhaus, C. A.; Poturovic, S.; Mashuta, M. S. Inorg.
Chem. 2002, 41, 4309.

3896 Organometallics, Vol. 22, No. 19, 2003
Chang et al.
Ta ble 5. Selected Bon d Dista n ces (Å) a n d An gles
standard (CDCl3, δ 7.24: acetone-d6, δ 2.04). The complexes
[M]CtCPh (1a , [M] ) [Ru] ) Cp(dppe)Ru; 1b, [M] ) [Ru′] )
Cp(PPh3)[P(OMe)3]Ru) were prepared by following the meth-
ods reported in the literature.19,8 FAB mass spectra were
recorded on a J EOL SX-102A spectrometer. Elemental analy-
ses and X-ray diffraction studies were carried out at the
Regional Center of Analytical Instrument located at the
National Taiwan University.
(d eg) of [Cp (d p p e)Ru CdC(P h )C(S-)N(dO)O]2CH2
(6a )
Ru(1)-C(1)
O(1)-C(2)
O(1)-C(1)
O(3)-C(11)
C(1)-C(4)
C(3)-C(4)
N(1)-C(3)
N(1)-C(2)
S(1)-C(3)
S(1)-C
2.041(3)
1.391(4)
1.404(4)
1.399(4)
1.396(4)
1.420(4)
1.330(4)
1.343(4)
1.773(3)
1.799(3)
Ru(2)-C(11)
O(2)-C(2)
O(3)-C(12)
O(4)-C(12)
C(11)-C(14)
C(13)-C(14)
N(2)-C(13)
N(2)-C(12)
S(2)-C(13)
S(2)-C
2.041(3)
1.221(4)
1.395(4)
1.208(4)
1.395(4)
1.417(4)
1.328(4)
1.357(4)
1.774(3)
1.795(3)
Syn th esis of [Ru ]CdC(P h )C(dNCO2Et)S (2a ). In
a
Schlenk flask charged with 1a (300.1 mg, 0.451 mmol) was
added CHCl3 (20 mL), and then EtO2CNCS (56.0 µL, 0.473
mmol) was injected by a microsyringe. The resulting solution
was stirred at room temperature for 1 h, and the color changed
from bright yellow to orange. The solvent was reduced to 1
mL under vacuum, and 30 mL of n-pentane was added to cause
precipitation of an orange powder. After filtration, the pre-
cipitate was washed with 10 mL of n-pentane and dried under
vacuum to give the product 2a (331.2 mg, 0.416 mmol, 92%
yield). Spectroscopic data of 2a are as follows. 1H NMR
(CDCl3): δ 7.79-6.69 (m, 25H, Ph), 4.60 (s, 5H, Cp), 4.07 (q,
2H, CH2, J H-H ) 7.10 Hz), 2.60, 2.15 (m, 2H, PCH2), 1.19 (t,
3H, CH3, J H-H ) 7.10 Hz). 31P NMR (CDCl3): δ 96.72. 13C NMR
(CDCl3): δ 162.0 (CO), 143.4 (SCN), 136.4-126.1 (m, Ph, CR
and Câ), 87.9 (Cp), 61.3 (OCH2), 30.4 (t, PCH2, J C-P ) 22.4
C(2)-O(1)-C(1) 125.5(3)
C(2)-N(1)-C(3) 116.5(3)
N(1)-C(2)-O(1) 119.8(3)
O(1)-C(1)-Ru(1) 114.4(2)
S(2)-C-S(1)
114.77(18)
117.7(2)
126.3(3)
116.0(2)
N(1)-C(3)-S(1)
N(1)-C(3)-C(4)
C(1)-C(4)-C(3)
C(3)-S(1)-C
118.4(3)
101.94(16) C(4)-C(3)-S(1)
metalation, oxygenation, and adduct formation have all
been recognized.16 The strength of the coordinated
thiolate’s nucleophilicity was established by the fact that
even weak electrophiles, such as CH2Cl2, are prone to
attack. In the past, alkylation of the trans-dithiolato-
ruthenium complex [Ru(PPh3)2dttd] by CH2Cl2, yielding
the chloromethyl thioether complexes [Ru(X)(PPh3)dttd-
CH2Cl], where X is azide or cyanide, has been re-
ported.17 Alkylation across cis thiolates, yielding a
methylene-bridged dithioether Ru complex, has been
reported lately.15 Similar additions of CH2Br2 across
adjacent sulfido sulfurs have been previously reported.18
Con clu d in g Rem a r k s. Reactions of two ruthenium
acetylide complexes with EtO2CNCS have yielded a
series of addition products. Cycloaddition of the CdS
bond of EtO2CNCS with the acetylide ligand gives the
four-membered-ring 2-iminothiete product. Opening of
the 2-iminothiete ring causes slow isomerization of
complex 2a to 3a , which undergoes alkylation by CH2-
Cl2 at the thione sulfur atom to yield the new six-
membered-ring oxazine complex 5a . Alkylation of com-
plex 3a by the chloromethyl group of 5a followed by loss
of EtCl affords the binuclear complex 6a with two
heterocyclic six-membered-ring ligands bridged by a
methylene group.
Hz), 14.0 (CH3). MS (FAB, m/z): 798.2 (M+ + 1), 666.2 (M+
-
EtO2CNCS), 565.5 (M+ - EtO2CNCS - CtCPh). Anal. Calcd
for C43H39O2NSP2Ru: C, 64.81; H, 4.93; N, 1.76. Found: C,
65.12; H, 5.09; N, 1.63.
Syn th esis of [Ru ′]CdC(P h )C(dNCO2Et)S (2b). In a
Schlenk flask charged with 1a (200.1 mg, 0.306 mmol) was
added CHCl3 (20 mL), and EtO2CNCS (39.6 µL, 0.336 mmol)
was injected by a microsyringe. The resulting solution was
stirred at room temperature for 1 h, and the color changed
from bright yellow to orange. The solvent was reduced to 1
mL under vacuum, and 20 mL of hexane was added to cause
precipitation of an orange powder. After filtration, the pre-
cipitate was washed with 10 mL of hexane and then dried
under vacuum to give the product 2b (199.4 mg, 0.254 mmol,
1
83% yield). Spectroscopic data of 2b are as follows. H NMR
(acetone-d6): δ 7.85-6.90 (m, 20H, Ph), 4.21 (s, 5H, Cp), 4.13
(q, 2H, CH2, J H-H ) 7.14 Hz), 3.42 (d, 9H, P(OMe)3, J H-P
)
11.12 Hz), 1.16 (t, 3H, CH3, J H-H ) 7.14 Hz). 31P NMR
(CDCl3): δ 152.72, 56.92 (2d, J P-P ) 67.13 Hz). 13C NMR
(CDCl3): δ 167.4, 161.8 (CO and SCN), 138.4-126.5 (m, Ph,
CR and Câ), 86.2 (Cp), 61.6 (OCH2), 52.8 (d, J C-P ) 7.5 Hz,
P(OMe)3), 14.7 (CH3). MS (FAB, m/z): 786.1 (M+ + 1), 553.1
(M+ - EtO2CNCS - CtCPh), 429.0 [M+ - EtO2CNCS - Ct
CPh - P(OMe)3]. Anal. Calcd for C38H39O5NSP2Ru: C, 58.15;
H, 5.01; N, 1.78. Found: C, 58.38; H, 5.24; N, 1.75.
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
Schlenk techniques. CH2Cl2 was distilled from CaH2 and
diethyl ether and THF from sodium benzophenone ketyl. All
other solvents and reagents were of reagent grade and were
used without further purification. NMR spectra were recorded
on Bruker AC-200 and AM-300WB FT-NMR spectrometers at
room temperature (unless stated otherwise) and are reported
in units of δ with residual protons in the solvents as an initial
Syn th esis of [Ru ]CdC(P h )C(dS)NdC(OEt)O (3a ). In a
Schlenk flask charged with 1a (200.3 mg, 0.301 mmol) was
added CHCl3 (20 mL), and then EtO2CNCS (37.3 µL, 0.316
mmol) was injected by a microsyringe. The resulting solution
was stirred at room temperature for 1 day. The solvent was
reduced to 1 mL under vacuum, and 30 mL of n-pentane was
added to cause precipitation of an orange-yellow powder. After
filtration, the precipitate was washed with 10 mL of n-pentane
and dried under vacuum to give a mixture of 2a and 3a (211.0
mg, 88% total yield) in a ratio of ca. 1:3. Spectroscopic data of
3a are as follows. 1H NMR (CDCl3): δ 7.79-6.95 (m, 25H, Ph),
3.88 (s, 5H, Cp), 3.79 (q, 2H, CH2, J H-H ) 7.05 Hz), 3.10, 2.65
(m, 2H, PCH2), 0.88 (t, 3H, CH3, J H-H ) 7.05 Hz). 31P NMR
(16) (a) Thompson, M. C.; Busch, D. H. J . Am. Chem. Soc. 1964, 86,
3651-3656. (b) Constable, E. C. Metals and Ligand Reactivity: An
Introduction to the Organic Chemistry of Metal Complexes, 2nd ed.;
VCH: Weinheim, Germany, 1996. (c) Musie, G.; Reibenspies, J . H.;
Darensbourg, M. Y. Inorg. Chem. 1998, 37, 302. (d) Grapperhaus, C.
A.; Darensbourg, M. Y. Acc. Chem. Res. 1998, 31, 451. (e) Darensbourg,
M. Y.; Tuntulani, T.; Reibenspies, J . H. Inorg. Chem. 1995, 34, 6287.
(f) Lyon, E. J .; Musie, G.; Reibenspies, J . H.; Darensbourg, M. Y. Inorg.
Chem. 1998, 37, 6942.
(17) (a) Sellmann, D.; Waeber, M.; Binder, H.; Boese, R. Z. Natur-
forsch., B: Chem. Sci. 1986, 41b, 1541. (b) dttd2- ) 2,3;8,9-dibenzo-
1,4,7,10-tetrathiadecane(2-).
(18) McKenna, M.; Wright, L. L.; Miller, D. J .; Tanner, L.; Halti-
wanger, R. C.; DuBois, M. R. J . Am. Chem. Soc. 1983, 105, 5329.
(CDCl3): δ 96.03. 13C NMR (CDCl3): δ 216.6 (t, CR, J C-P
13.6 Hz), 194.6 (CS), 155.5 (CO), 143.4, 134.0-126.6 (m, Ph,
and Câ), 84.9 (Cp), 64.0 (OCH2), 29.8 (t, PCH2, J C-P ) 22.7
)
(19) Synthesis of acetylide: (a) Bruce, M. I. Aust. J . Chem. 1977,
30, 1602. (b) Oshima, N.; Suzuki, H.; Moro-oka, Y. Chem. Lett. 1984,
1161.

Reactions of Ru Acetylide Complexes with EtO2CNCS
Organometallics, Vol. 22, No. 19, 2003 3897
Hz), 14.0 (CH3). MS (FAB, m/z): 797.0 (M+), 565.0 (M+ - EtO2-
CNCS - CtCPh).
product 6a (64.2 mg, 0.042 mmol, 33% yield). Spectroscopic
data of 6a are as follows. H NMR (CDCl3): δ 7.63-7.02 (m,
1
50H, Ph), 4.20 (s, 2H, CH2), 3.93 (s, 10H, Cp), 3.43, 2.55 (m,
4H, PCH2). 31P NMR (CDCl3): δ 98.84. 13C NMR (CDCl3): δ
154.2 (CO), 143.6 (NCS), 133.5-127.6 (m, Ph and Câ), 84.4
(Cp), 30.9 (CH2), 29.7 (t, PCH2, J C-P ) 22.4 Hz). MS (FAB,
m/z): 1551.0 (M+ + 1), 593.0 (M+ + CO - organic ligand), 565.1
(M+ - organic ligand). Anal. Calcd for C83H70O4N2S2P4Ru2: C,
64.33; H, 4.55; N, 1.81. Found: C, 64.11; H, 4.78; N, 1.68.
X-r a y An a lysis of 2b, 3a , 5a , a n d 6a . Single crystals
suitable for X-ray diffraction studies were grown as mentioned
above. The chosen single crystal was glued to a glass fiber and
mounted on a SMART CCD diffractometer. The data were
collected with use of 3 kW sealed-tube molybdenum KR
radiation (λ ) 0.7107 Å). The exposure time was 5 s per
frame.20 The intensity was intergrated, and absorption cor-
rections were applied by using SADABS.21 Data were processed
and refined by the SHELXTL22 program. Hydrogen atoms were
placed geometrically using the riding model with thermal
parameters set to 1.2 times those for the atoms to which the
hydrogen is attached and 1.5 times those for the methyl
hydrogens. Crystal data for 2b, 3a , 5a , and 6a are listed in
Table 1. Final values of all refined atomic positional param-
eters (with esd’s) and tables of thermal parameters are given
in the Supporting Information.
Obser va t ion of t h e In t er m ed ia t e {[R u ]CdC(P h )C-
(SCH2Cl)NC(OEt)O}[Cl] (4a ). In a Schlenk flask charged
with a mixture of 2a and 3a in a ratio of ca. 1:3 was added
CH2Cl2 (20 mL). The reaction was monitored by 31P NMR
spectroscopy. The resulting solution was stirred at room
temperature for hours, and the additional intermediate {[Ru]-
CdC(Ph)C(SCH2Cl)NC(OEt)O}[Cl] (4a ) was observed. We
failed to isolate 4a . Spectroscopic data of 4a are as follows. 1H
NMR (CDCl3): δ 4.70 (CH2Cl), 4.12 (s, 5H, Cp), 4.06 (q, 2H,
CH2, J H-H ) 7.02 Hz), 1.04 (t, 3H, CH3, J H-H ) 7.02 Hz). 31P
NMR (CDCl3): δ 92.71. MS (m/z, Ru,102 Cl35): 846.0 (M+ - Cl),
593.0 (M+ - Cl + CO - organic ligand), 565.0 (M+ - Cl -
organic ligand).
Syn th esis of [Ru ]CdC(P h )C(SCH2Cl)NC(dO)O (5a ). In
a Schlenk flask charged with 2a (200.1 mg, 0.251 mmol) was
added CH2Cl2 (50 mL). The resulting solution was stirred at
room temperature for 4 days, and the color changed from
orange-yellow to yellow. The solvent was removed under
vacuum, and the yellow precipitate was washed with 2 × 10
mL of hexane and dried under vacuum to give the product 5a
(178.7 mg, 0.219 mmol, 87% yield). Spectroscopic data of 5a
are as follows. 1H NMR (CDCl3): δ 7.70-7.12 (m, 25H, Ph),
4.86 (s, 2H, CH2), 3.95 (s, 5H, Cp), 3.42, 2.54 (m, 4H, PCH2-
CH2P). 31P NMR (CDCl3): δ 98.65. 13C NMR (CDCl3): δ 233.6
(t, CR, J C-P ) 14.5 Hz), 152.1 (CO), 139.5 (NCS), 133.2-128.1
Ack n ow led gm en t. We are grateful for support of
this work by the National Science Council, Taiwan,
Republic of China.
(m, Ph and Câ), 84.4 (Cp), 43.1 (CH2), 29.7 (t, PCH2, J C-P
)
22.4 Hz). MS (FAB, m/z): 818.1 (M+ + 1), 593.1 (M+ + CO -
organic ligand), 565.1 (M+ - organic ligand). Anal. Calcd for
Su p p or tin g In for m a tion Ava ila ble: Details about the
X-ray crystal structures, including diagrams and tables of
crystal data and structure refinement details, atomic coordi-
nates, bond lengths and angles, and anisotropic displacement
parameters for 2b, 3a , 5a , and 6a . This material is available
free of charge via the Internet at http://pubs.acs.org.
C
42H36O2NSClP2Ru: C, 61.72; H, 4.44; N, 1.71. Found: C,
62.07; H, 4.72; N, 1.63.
Syn th esis of [[Ru ]CdC(P h )C(S-)NC(dO)O]2CH2 (6a ).
In a Schlenk flask charged with 2a (200.1 mg, 0.251 mmol)
was added CH2Cl2 (10 mL). The resulting solution was stirred
at room temperature for 4 days to give a mixture of 5a and
6a in a ratio of ca. 3:2. Complexes 5a and 6a were separated
by their different solubilities in acetone. Thus, after the solvent
was removed under vacuum, 30 mL of cold acetone was added.
Complex 6a precipitated out from the acetone solution. After
filtration, the yellow precipitate was washed with 2 × 5 mL
of cold acetone and then dried under vacuum to give the
OM030341W
(20) X-ray: SAINT (Siemens Area Detector Intergration) program;
Siemens Analytical X-ray: Madison, WI, 1995.
(21) The SADABS program is based on the method of Blessing;
see: Blessing, R. H. Acta Crystallogr., Sect. A 1995, 51, 33.
(22) SHELXTL: Structure Analysis Program, version 5.04; Siemens
Industrial Automation, Inc., Madison, WI, 1995.