Synthesis of ruthenium triazolato and tetrazolato complexes by 1,3-dipolar cycloadditions of ruthenium azido complex with alkynes and alkenes and regiospecific alkylation of triazolates

Article abstract of DOI:10.1021/om030079r

The [3+2] cycloaddition reactions of alkynes and alkenes with ruthenium azido complex [Ru]-N₃ (1, [Ru] = (η⁵-C₅H₅)(dope)Ru, dppe = Ph₂PCH₂CH₂PPh₂) have been investigated. The metal-bound heterocyclic complexes produced are triazolates [Ru]N₃C₂(CO₂Me)₂ (2) and [Ru]N₃C₂HCO₂Me (3) from dimethyl acetylene dicarboxylate and methyl propiolate, respectively. Reaction of 1 with fumaronitrile in CH₂Cl₂ at room temperature results in removal of a HCN molecule and produces the triazolato complex [Ru]N₃C₂HCN (4). In contrast, reaction of tetracyanoethene with 1 affords the tetrazolato complex [Ru]N₄C[C(CN)=C(CN)₂] (5). The structures of these complexes are all clearly established as N(2)-bound. Alkylation of 2 with organic bromides causes cleavage of the Ru - N bond and affords [Ru]-Br and N(1)-alkylated five-membered-ring organic triazoles N₃(R)C₂(CO₂Me)₂ (6a, R = CH₂C₆F₅; 6b, R = CH₂Ph; 6c, R = CH₂CO₂Me). Reaction of 3 with excess methyl propiolate gives a mixture of Z- and E-form zwitterionic N(1)-bound N(3)-alkylated-4-substituted triazolato complexes [Ru]N₃(CH=CHCO₂Me)C₂H(CO₂) (7) in a ratio of ca. 4:1. Reaction of (Z)-7 with ICH₃ affords {[Ru]N₃(CH=CHCO₂Me)C₂H(CO₂Me)}[I] (8a) and the following cleavage of the Ru-N bond gives [Ru]-I and an organic triazole, N₃(CH=CHCO₂Me)C₂H(CO₂Me) (9a). A regiospecific alkylation happens by treatment of 3 with organic halides and gives a series of cationic N(1)-bound N(3)-alkylated-4-substituted triazolato complexes exclusively with high yields. The structures of 2, 3, 4, 5, (Z)-7, and 10a have been determined by single-crystal X-ray diffraction analysis.

Full text of DOI:10.1021/om030079r

Organometallics 2003, 22, 3107-3116
3107
Syn th esis of Ru th en iu m Tr ia zola to a n d Tetr a zola to
Com p lexes by 1,3-Dip ola r Cycloa d d ition s of Ru th en iu m
Azid o Com p lex w ith Alk yn es a n d Alk en es a n d
Regiosp ecific Alk yla tion of Tr ia zola tes
Chao-Wan Chang*,† and Gene-Hsiang Lee‡
National University Preparatory School for Overseas Chinese Students, Linkou,
Taipei Hsien 244, Taiwan, Republic of China, and Instrumentation Center, College of Science,
National Taiwan University, Taipei, Taiwan 106, Republic of China
Received J anuary 31, 2003
The [3+2] cycloaddition reactions of alkynes and alkenes with ruthenium azido complex
[Ru]-N3 (1, [Ru] ) (η5-C5H5)(dppe)Ru, dppe ) Ph2PCH2CH2PPh2) have been investigated.
The metal-bound heterocyclic complexes produced are triazolates [Ru]N3C2(CO2Me)2 (2) and
[Ru]N3C2HCO2Me (3) from dimethyl acetylene dicarboxylate and methyl propiolate, respec-
tively. Reaction of 1 with fumaronitrile in CH2Cl2 at room temperature results in removal
of a HCN molecule and produces the triazolato complex [Ru]N3C2HCN (4). In contrast,
reaction of tetracyanoethene with 1 affords the tetrazolato complex [Ru]N4C[C(CN)dC(CN)2]
(5). The structures of these complexes are all clearly established as N(2)-bound. Alkylation
of 2 with organic bromides causes cleavage of the Ru-N bond and affords [Ru]-Br and N(1)-
alkylated five-membered-ring organic triazoles N3(R)C2(CO2Me)2 (6a , R ) CH2C6F5; 6b ,
R ) CH2Ph; 6c, R ) CH2CO2Me). Reaction of 3 with excess methyl propiolate gives a mixture
of Z- and E-form zwitterionic N(1)-bound N(3)-alkylated-4-substituted triazolato complexes
[Ru]N3(CHdCHCO2Me)C2H(CO2) (7) in a ratio of ca. 4:1. Reaction of (Z)-7 with ICH3 affords
{[Ru]N3(CHdCHCO2Me)C2H(CO2Me)}[I] (8a ) and the following cleavage of the Ru-N bond
gives [Ru]-I and an organic triazole, N3(CHdCHCO2Me)C2H(CO2Me) (9a ). A regiospecific
alkylation happens by treatment of 3 with organic halides and gives a series of cationic
N(1)-bound N(3)-alkylated-4-substituted triazolato complexes exclusively with high yields.
The structures of 2, 3, 4, 5, (Z)-7, and 10a have been determined by single-crystal X-ray
diffraction analysis.
In tr od u ction
spectively. Similar reactions with alkynes8,13,17,19,20,26-28
produce triazolates; alkenes, however, react very slowly
1,3-Dipolar cycloaddition1-6 is a common process in
organic chemistry. Among various 1,3-dipoles, organic
azides3,6 are particularly important for synthesizing
heterocyclic compounds. By analogy, coordinated azide
in metal complexes can also undergo cycloaddition.7Thus,
azido complexes have been reported to react with
nitriles8-21 and isonitriles9,22-25 to produce metal-
nitrogen- and metal-carbon-bonded tetrazolates, re-
and mostly afford impure products.8,19 Azido complexes
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1985, 102, 157.
† National University Preparatory School for Overseas Chinese
Students.
‡ National Taiwan University.
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Huisgen, R. Angew. Chem., Int. Ed. Engl. 1963, 2, 633. (c) Huisgen,
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10.1021/om030079r CCC: $25.00 © 2003 American Chemical Society
Publication on Web 05/23/2003

3108 Organometallics, Vol. 22, No. 15, 2003
Chang and Lee
react with carbon disulfide8,9,13,15-17,29 to produce thio-
thiatriazolate. Several azido complexes have been found
to react with organic isothiocyanates8,15,19,20,30 and alkyl
thiocyanates13,19,20 to give tetrazolinethionates and
5-(thioalkyl)tetrazolates, respectively. A survey8 of the
azido complexes known to take part in cycloaddition
reactions discloses that the metals involved are most
often palladium(II),31 platium(II),16 or cobalt(III),19,32
although a whole range of other transition metals21,33-35
has been used. In this paper, we reported the [3+2]
cycloaddition reactions of alkynes and alkenes with the
ruthenium azido complex. The stable triazolato and
tetrazolato products we obtained in all cases were N(2)-
bound. A series of regiospecific alkylation of triazolato
complexes occurred. It was hoped that this type of
reaction could be developed into a high-yield synthetic
procedure for the exclusive preparation of 1,4,5-trisub-
stituted and 3,4-disubstituted triazoles. This hope was
partially realized. We successfully synthesized the 1,4,5-
trisubstituted triazoles from the 4,5-disubstituted tri-
azolate but the isolation failed. Alkylation of the 4-sub-
stituted triazolates does proceed in high yield with the
exclusive formation of N(1)-bound 3,4-disubstituted
triazolates. We now disclose the results of detailed
synthetic and structural investigations herein.
exhibit two resonances for its anisochronous methoxy-
carbonyl groups. The 31P NMR resonance of 2 appears
at δ 87.3. The FAB mass spectrum displays a parent
peak at m/z 749.2 (M+). In a previous study, the triazole
and tetrazole anion could be coordinated by a metal
center through either its N(1) or N(2) nitrogen atom.8
Molecular orbital calculations36-38 indicate that these
two bonding modes are essentially isoenergetic. Evi-
dence obtained to date indicates that either two isomers
N(1) and N(2) are formed simultaneously8,13,19,20,36-38 or
only the N(2) isomer is produced exclusively.8,13,19,20 In
our case, the N(2)-bound isomer is produced exclusively.
Surprisingly, the reaction of 1 with either dimethyl
fumarate or dimethyl maleate gives 2, identical with
the reaction of 1 with dimethyl acetylene dicarboxylate.
The yields of the reactions are 91% and 90%, respec-
tively. The reaction is completed in one week at room
temperature. In both reactions, complex 2 is formed by
[3+2] cyclization between the azido ligand and a CdC
double bond following removal of a H2 molecule. There
are a few examples of cycloaddition of alkenes to
coordinated azides,8,19,39 but most of the alkenes inves-
tigated did not produce pure products and the triazoli-
nates produced were generally thermally unstable and
base sensitive. Generally, these reactions occur over a
long period of time as with the corresponding alkyne
reactions.19 To our knowledge, this is the first example
that cycloaddition of alkenes with the ruthenium azido
complex via removal of one molecule yields a thermally
stable, pure, and high-yield triazolato product. The
structure of 2 produced from dimethyl fumarate is
determined to establish the geometry and the bonding
mode about the triazolato ligand. Complex 2 was
characterized by a single-crystal X-ray diffraction analy-
sis; an ORTEP drawing is shown in Figure 1. Crystal
and intensity collection data are given in Table 1.
Selected bond distances and bond angles are given in
Table 2. The triazolato ligand is N(2)-bound to ruthe-
nium and the five atoms of the triazolato ring are
essentially planar.
Rea ction of 1 w ith Meth yl P r op iola te. Treatment
of complex 1 with a 5-fold excess of methyl propiolate
in CH2Cl2 at room temperature for 8 h affords the N(2)-
bound 4-methoxycarbonyl-1,2,3-triazolato complex, [Ru]-
N3C2HCO2Me (3), with 73% isolated yield. By monitor-
ing the reaction with 31P NMR spectroscopy, two singlet
resonances at δ 88.40 and 88.20 attributed to the N(1)-
and N(2)-bound isomers, respectively, were observed at
the initial stage of the reaction. The N(1)-bound isomer,
in hours at room temperature, converted to the N(2)-
bound isomer. The molecular structure of 3 was deter-
mined by an X-ray diffraction study; an ORTEP drawing
is shown in Figure 2 and selected bond distances and
bond angles are given in Table 1. The triazolato ligand
is N(2)-bound. The five-membered triazolato ring ex-
hibits an irregular pentagonal structure and is es-
sentially planar.
Resu lts a n d Discu ssion
P r ep a r a tion of th e Azid o Com p lex. Treatment of
[Ru]-Cl ([Ru] ) (η5-C5H5)(dppe)Ru, dppe ) Ph2PCH2-
CH2PPh2) with NaN3 in ethanol at reflux for 4 h affords
the orange-yellow product [Ru]-N3 (1) with an isolated
yield of 99%. The 31P NMR spectrum of 1 displays a
singlet resonance at δ 81.5 assigned to the dppe ligand.
The 1H NMR spectrum of 1 displays a singlet resonance
at δ 4.47, which is assigned to Cp. Complex 1 is soluble
in polar solvents such as CH2Cl2, CHCl3, and acetone,
moderately soluble in diethyl ether, and stable in
solution and in the air.
Rea ction of 1 w ith Dim eth yl Acetylen e Dica r -
boxyla te. Treatment of complex 1 with a 5-fold excess
of dimethyl acetylene dicarboxylate in CH2Cl2 at room
temperature for 24 h affords the N(2)-bound 4,5-bis-
(methoxycarbonyl)-1,2,3-triazolato complex [Ru]N3C2-
(CO2Me)2 (2) with 90% isolated yield. The structure of
2 is clearly established as the N(2)-bound isomer from
1
the appearance of its H NMR spectrum ,which shows
a singlet at δ 3.62 for the six methoxycarbonyl protons.
1
The H NMR spectrum of a N(1)-bound isomer would
(26) Gorth, H.; Henry, M. C. J . Organomet. Chem. 1967, 9, 117.
(27) Kozima, S.; Itano, T.; Mihara, N.; Sisido, K.; Isida, T. J .
Organomet. Chem. 1972, 44, 117.
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(29) (a) Ziolo, R. F.; Dori, Z. J . Am. Chem. Soc. 1968, 90, 6560. (b)
Ziolo, R. F.; Thich, J . A.; Dori, Z. Inorg. Chem. 1972, 11, 626.
(30) Sato, F.; Etoh, M.; Sato, M. J . Organomet. Chem. 1974, 70, 101.
(31) (a) Fehlhammer, W. P.; Beck, W. Z. Naturforsch., Teil B 1983,
38, 546. (b) Geisenberger, J .; Erbe, J .; Heidrich, J .; Nagel, U.; Beck,
W. Z. Naturforsch., Teil B 1987, 42, 55.
(32) Hsieh, B. T.; Nelson, J . H.; Milosavljevic, E. B.; Beck, W.;
Kemmerich, T. Inorg. Chim. Acta. 1987, 133, 267.
(33) Blunden, S. J .; Mahon, M. F.; Molloy, K. C.; Waterfield, P. C.
J . Chem. Soc., Dalton Trans. 1994, 2135.
(34) (a) Guilard, R.; Perrot, I.; Tabard, A.; Richard, P.; Lecomte, C.
Inorg. Chem. 1991, 30, 19. (b) Guilard, R.; Perrot, I.; Tabard, A.;
Richard, P.; Lecomte, C. Inorg. Chem. 1991, 30, 27.
(35) Nomiya, K.; Noguchi, R.; Oda, M. Inorg. Chem. Acta 2000, 298,
24.
(36) Nelson, J . H.; Schmitt, D. L.; Henty, R. A.; Moore, D. W.;
J onassen, H. B. Inorg. Chem. 1970, 9, 2678.
(37) Redfield, D. A.; Nelson, J . H.; Henry, R. A.; Moore, D. W.;
J onassen, H. B. J . Am. Chem. Soc. 1974, 96, 6298.
(38) Kieft, R. L.; Peterson, W. M.; Blundell, G. L.; Horton, S.; Henry,
R. A.; J onasson, H. B. Inorg. Chem. 1976, 15, 1721.
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170, 27. (b) Huisgen, R.; Szeimies, G.; Mobius, L. Chem. Ber. 1966,
99, 475.

Ruthenium Triazolato and Tetrazolato Complexes
Organometallics, Vol. 22, No. 15, 2003 3109
F igu r e 2. ORTEP drawing of 3; thermal ellipsoids are
drawn at the 50% probability level.
F igu r e 1. ORTEP drawing of 2; thermal ellipsoids are
drawn at the 50% probability level.
Ta ble 1. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for 2, 3, a n d 4
2
3
4
Ru-N2
N1-N2
N2-N3
N3-C1
N1-C2
C1-C2
2.090(2)
1.331(3)
1.332(3)
1.351(3)
1.352(3)
1.400(4)
2.085(2)
1.352(3)
1.336(3)
1.359(3)
1.337(3)
1.382(4)
2.0990(18)
1.340(3)
1.325(3)
1.355(3)
1.331(3)
1.367(4)
P1-Ru-P2
N2-Ru-P1
N2-Ru-P2
Ru-N2-N1
Ru-N2-N3
N2-N3-C1
N1-N2-N3
N2-N1-C2
N3-C1-C2
N1-C2-C1
85.13(3)
86.48(6)
89.89(6)
121.4(2)
125.2(2)
105.5(2)
113.4(2)
105.6(2)
107.8(2)
107.7(2)
83.60(3)
90.78(7)
89.67(6)
124.81(17)
122.31(18)
104.8(2)
112.8(2)
105.3(2)
108.5(2)
108.6(3)
83.88(3)
86.80(6)
90.16(5)
124.09(15)
123.14(14)
104.7(2)
112.64(18)
105.7(2)
108.6(2)
108.2(2)
Ta ble 2. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for 5
F igu r e 3. ORTEP drawing of 4; thermal ellipsoids are
drawn at the 50% probability level.
Ru-P1
Ru-N2
N2-N3
N3-N4
N5-C4
N7-C6
C2-C3
C3-C6
2.2768(5)
2.0702(16)
1.356(2)
1.312(3)
1.130(4)
1.139(3)
1.303(4)
1.391(4)
Ru-P2
N1-N2
N1-C1
N4-C1
N6-C5
C1-C2
C2-C4
C3-C5
2.2927(5)
1.328(2)
1.351(3)
1.342(3)
1.148(4)
1.438(3)
1.530(4)
1.501(4)
4.58 attributed to Cp. The 31P NMR resonance of 4
appears at δ 88.2. In the 13C NMR, a resonance at δ
119.1 is assigned to CN. The FAB mass spectrum
displays a parent peak at m/z 658.2 (M+). In principle,
the cycloaddition of fumaronitrile to coordinated azide
can take place via CdC or CtN. The reaction of
coordinated azide in Ni(II) with CH2dCHCN gave a
triazolinato complex.8 A pathway via direct cyclization
of HCtCCN with azide resulting in the formation of
triazolate also occurred.39b The product 4 is clearly
established to be formed by [3+2] cyclization between
the azido ligand and a CdC double bond following
removal of a HCN molecule. The structure of 4 was
determined by an X-ray diffraction study; an ORTEP
drawing is shown in Figure 3 and selected bond dis-
tances and bond angles are given in Table 1. The
coordination geometry is very similar to that of 3. As
observed, the triazolato ring is N(2)-bound. The bond
distances of the triazolato ring are similar to but a little
P1-Ru-P2
N2-Ru-P2
Ru-N2-N3
N2-N3-N4
N4-C1-N1
N1-C1-C2
C3-C2-C4
C2-C3-C6
C6-C3-C5
84.103(19)
88.13(5)
119.45(13)
108.41(18)
113.14(19)
127.6(2)
118.1(2)
123.9(3)
117.1(3)
N2-Ru-P1
Ru-N2-N1
N2-N1-C1
N3-N4-C1
N4-C1-C2
C1-C2-C3
C1-C2-C4
C2-C3-C5
91.04(5)
128.70(13)
102.37(18)
104.99(18)
119.2(2)
127.6(3)
114.3(2)
118.9(3)
Rea ction of 1 w ith F u m a r on itr ile. Treatment of
1 with fumaronitrile at room temperature for 12 h
affords the N(2)-bound 4-cyano-1,2,3-triazolato complex,
[Ru]N3C2HCN (4), with 80% isolated yield. The 1H NMR
spectrum of 4 displays a characteristic singlet resonance
at δ 7.03 assigned to CH and a singlet resonance at δ

3110 Organometallics, Vol. 22, No. 15, 2003
Chang and Lee
Sch em e 1
Sch em e 2
Apparently, not only the steric effect but also the
inductive effect should be considered as important
driving forces for the reaction. Typically, tetrazoles are
prepared from the corresponding nitriles by reaction
with a hydrazoic source (e.g., sodium azide and am-
monium chloride).41-43 Alternative strategies, involving
different azide anion sources such as trimethylsilyl azide
in the presence of dialkyltin oxide,44 have been devel-
oped for the conversion of amides into 1,5-disubstituted
tetrazoles.45,46 In addition, reaction of a cyano-substi-
tuted cyclopropenyl complex with trimethylsilyl azide
reportedly gave a tetrazolato complex.47
F igu r e 4. ORTEP drawing of 5; thermal ellipsoids are
drawn at the 50% probability level.
less than those of 3. Therefore, the bonding mode is the
same as 3 and the triazolate ring of 4 is marginally
smaller.
Rea ction s of Tr ia zola to Com p lexes w ith Elec-
tr op h iles. Alkylation of 2 with a 10-fold excess of
BrCH2C6F5 in CHCl3 at room temperature for one week
causes cleavage of the Ru-N bond and affords [Ru]-Br
and a N(1)-alkylated five-membered-ring organic tria-
zole N3(CH2C6F5)C2(CO2Me)2 (6a ) (Scheme 2). At 50 °C
and with a 20-fold excess of BrCH2C6F5, the reaction is
completed in 1 day. The alkylation is monitored by NMR
spectroscopy. In the 31P NMR spectrum, the resonance
of 2 at δ 87.25 disappeared and the resonance at δ 79.86
Rea ction of 1 w ith TCNE. The reaction of 1 with
tetracyanoethene (TCNE) at room temperature for 24
h affords the tetrazolato complex [Ru]N4C[C(CN)d
C(CN)2] (5) with 80% isolated yield. The cycloaddition
of C(CN)2dC(CN)2 to coordinated azide can take place
via CdC or CtN. That the product 5 is obtained when
CtN adds to coordinated azide is established by a
single-crystal X-ray diffraction study. An ORTEP dia-
gram is shown in Figure 4 and selected bond distances
and bond angles are given in Table 2. The planar five-
membered tetrazolato ring is coordinated to the Ru
center via the N(2) atom. Although the variation in bond
distances is larger than those of triazolates, the bonding
mode of this tetrazolate is probably best described as a
π-delocalized bond in this five-membered ring. Reactiv-
ity of the reaction is highly related to the nature of the
nitrile. Benzonitrile, acetonitrile, CF3CN, and HPhCd
C(CN)2 do not react with complex 1 even under vigorous
conditions. Recently we reported an interesting reaction
of pentamethylcyclopentadienyl dppp (dppp ) Ph2PCH2-
CH2CH2PPh2) ruthenium azido complex with ICH2CN
affording an N-coordinated iodoacetonitrile complex.40
1
attributed to [Ru]-Br appeared. In the H NMR spec-
trum a singlet resonance appears at δ 4.56 attributed
to Cp of [Ru]-Br and two singlet resonances appear at
δ 3.98 and 3.88 attributed to two anisochronous meth-
oxycarbonyl groups of 6a . The FAB mass spectrum of
the crude mixture displayed parent peaks at m/z 646.1
and 366.1 attributed to [Ru]-Br and 6a , respectively.
Similar reaction of 2 with other organic bromides gives
(41) Palazzi, A.; Stagni, S.; Bordoni, S.; Monari, M.; Selva, S.
Organometallics 2002, 21, 3774.
(42) Koguro, K.; Oga, T.; Mitsui, S.; Orita, R. Synthesis 1998, 910.
(43) Demko, Z. P.; Sharpless, K. B. J . Org. Chem. 2001, 66, 7954.
(44) Wittenberger, S. J .; Donner, B. G. J . Org. Chem. 1993, 58, 4139.
(45) Duncia, J . V.; Pierce, M. E.; Santella, J . B., III. J . Org. Chem.
1991, 56, 2395.
(46) Thomas, E. W. Synthesis 1993, 676.
(47) Chang, K. H.; Lin, Y. C.; Liu, Y. H.; Wang, Y. J . Chem. Soc.,
Dalton Trans. 2001, 3154.
(40) Chang, C. W.; Lin, Y. C.; Lee, G. H.; Wang, Y. Organometallics
2000, 19, 3211.

Ruthenium Triazolato and Tetrazolato Complexes
Organometallics, Vol. 22, No. 15, 2003 3111
Sch em e 3
[Ru]-Br and N(1)-alkylated five-membered-ring organic
triazoles N3(R)C2(CO2Me)2 (6b, R ) CH2Ph; 6c, R )
CH2CO2CH3) (Scheme 2). The structures of these free
triazoles are clearly established as N(1)-alkylated from
1
the appearance of their H NMR spectra which exhibit
two proton resonances for their anisochronous meth-
oxycarbonyl groups. [Ru]-Br is easily isolated as a
precipitate in n-pentane solution but the free triazoles
6a -c, which mix with excess organic halides in n-
pentane, are hard to isolated. Most attempts at isolating
the triazole from the mixture have been unsuccessful.
An alkylation of triazolato cobalt chelate complexes was
made by Nelson and co-workers,19 but isolation of the
free triazole was not successful either. Noticeably, there
is no reaction between organic iodides with 2. Treatment
of 2 with HCl(aq) causes a hydrolysis and no Ru-N bond-
breaking is observed.
Rea ction of 3 w ith Meth yl P r op iola te. Upon
letting the CHCl3 solution of 3 with excess methyl
propiolate stand at room temperature for days, a
mixture of the Z- and E-form zwitterionic triazolato
complex [Ru]N3(CHdCHCO2Me)C2H(CO2) (7) was ob-
tained in a ratio of ca. 4:1 (observed by 1H NMR
spectroscopy after isolation) (Scheme 3). The reaction
F igu r e 5. ORTEP drawing of (Z)-7; thermal ellipsoids are
drawn at the 30% probability level.
and d-acetone. Complex 7 is possibly formed by adding
a methyl propiolate molecule to the hydrolyzed 3. The
purification of (Z)-7 was achieved by washing (E)-7 away
with diethyl ether three times. The molecular structure
of (Z)-7 was determined by an X-ray diffraction study;
an ORTEP drawing is shown in Figure 5 and selected
bond distances and bond angles are given in Table 3.
The triazolato ligand is N(1)-bound. The five-membered
triazolato ring exhibits an irregular pentagonal struc-
ture and is essentially planar. The O1-C3 and O2-C3
distances of 1.250(6) and 1.249(7) Å, respectively, are
both between the C-O double bond and the single bond,
1
was monitored by 31P NMR and H NMR. After treat-
ment of 3 with excess methyl propiolate in CDCl3 for
days, the 31P NMR spectrum showed two signals ap-
pearing at δ 86.16 and 85.76 in a ratio of ca. 4:1
attributed to (Z)-7 and (E)-7, respectively. In the 1H
NMR spectrum, two sets of AX pattern resonances
appearing at δ 7.57, 5.42 (d, J H-H ) 10.31 Hz) and δ
8.65, 4.95 (d, J H-H ) 14.32 Hz) in a ratio of ca. 4:1 are
assigned to the two vinyl protons of (Z)-7 and (E)-7,
respectively. The same reaction is observed in CD3CN

3112 Organometallics, Vol. 22, No. 15, 2003
Chang and Lee
Ta ble 3. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for (Z)-7
Ru-P1
Ru-N1
N1-N2
N1-C2
C1-C3
C5-C6
O2-C3
O4-C6
2.2831(12)
2.108(4)
1.327(5)
1.362(6)
1.522(7)
1.462(8)
1.249(7)
1.341(7)
Ru-P2
N2-N3
N3-C1
C1-C2
C4-C5
O1-C3
O3-C6
O4-C7
2.2893(12)
1.344(5)
1.362(6)
1.363(7)
1.316(7)
1.250(6)
1.203(6)
1.441(7)
P1-Ru-P2
N1-Ru-P2
Ru-N1-C2
N2-N3-C1
N3-C1-C2
C2-C1-C3
O1-C3-O2
O2-C3-C1
C4-C5-C6
83.78(4)
89.47(10)
131.8(3)
111.2(4)
104.7(4)
128.1(4)
128.5(5)
117.7(5)
130.0(5)
N1-Ru-P1
Ru-N1-N2
N1-N2-N3
C2-N1-N2
N3-C1-C3
N1-C2-C1
O1-C3-C1
N3-C4-C5
93.58(10)
117.6(3)
106.3(2)
109.4(4)
126.8(4)
108.3(4)
113.7(5)
125.7(5)
indicating the delocalized π-bonding mode. The N3-
C4-C5 and C4-C5-C6 angles of 125.7(5)° and 130.0-
(5)°, respectively, are larger than that of a typical C(sp2)
hybridization, possibly resulting from the steric crowd-
ing of the two substitutes in the Z conformation.
Rea ction of (Z)-7 w ith Electr op h iles. Treatment
of (Z)-7 with ICH3 at room temperature for 24 h gives
(Z)-{[Ru]N3(CHdCHCO2Me)C2H(CO2CH3)}[I] (8a ) with
90% isolated yield. Letting the CHCl3 solution of (Z)-7
and a 10-fold excess of ICH3 stand at room temperature
for 4 days causes cleavage of the Ru-N bond and gives
[Ru]-I and an organic triazole, (Z)-N3(CHdCHCO2Me)-
C2H(CO2Me) (9a ). The excess CH3I and CH2Cl2 were
removed under vacuum. [Ru]-I and 9a were separated
by extracting the residue with n-pentane. The organic
product 9a was identified by high-resolution mass
spectroscopy. The reaction of (Z)-7 with BrCH2C6F5 is
similar to that of CH3I, giving (Z)-{[Ru]N3(CHdCHCO2-
Me)C2H(CO2CH2C6F5)}[Br] (8b) in 20 h at room tem-
perature, and the following Ru-N bond cleavage gives
[Ru]-Br and an organic triazole, (Z)-N3(CHdCHCO2Me)-
C2H(CO2CH2C6F5) (9b). [Ru]-Br is easily isolated as
precipitate in n-pentane solution but the organic product
9b, which mixed with excess organic halides in n-
pentane, is hard to isolate.
F igu r e 6. ORTEP drawing of 10a ; thermal ellipsoids are
drawn at the 50% probability level.
Ta ble 4. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for 10a
Ru-P1
Ru-N1
N1-N2
N1-C2
C1-C3
O2-C3
2.2896(8)
2.106(3)
1.329(4)
1.354(4)
1.480(5)
1.326(4)
Ru-P2
N2-N3
N3-C1
C1-C2
O1-C3
N3-C5
2.2863(8)
1.335(4)
1.355(4)
1.368(5)
1.197(4)
1.478(4)
P1-Ru-P2
N1-Ru-P2
Ru-N1-C2
N2-N3-C1
N3-C1-C2
C2-C1-C3
O1-C3-O2
O2-C3-C1
84.51(3)
89.58(7)
126.7(2)
111.0(3)
104.7(3)
130.1(3)
125.2(5)
108.9(3)
N1-Ru-P1
Ru-N1-N2
N1-N2-N3
C2-N1-N2
N3-C1-C3
N1-C2-C1
O1-C3-C1
N3-C5-C6
90.36(7)
123.3(2)
106.9(2)
108.9(3)
125.0(3)
108.4(3)
125.9(3)
111.6(3)
with other organic halides also give exclusively cationic
N(1)-bound N(3)-alkylated-4-methoxycarbonyl triazolato
complexes {[Ru]N3(R)C2HCO2Me}[Br] (10b, R ) CH2-
Ph, X ) Br; 10c, R ) CH2CO2Me, X ) Br; 10d , R )
CH3, X ) I) with high yields (Scheme 3). Complexes
10a -d are stable in CHCl3 solution with excess organic
bromides and no further Ru-N bond breaking was
observed at room temperature or at reflux. An ORTEP
drawing of 10a is shown in Figure 6, and selected bond
distances and bond angles are given in Table 4. The
N(3)-alkylated triazolato ligand is N(1)-bound.
The alkylation of 4 is complicated. Treatment of 4
with organic halides at room temperature yields several
alkylated products and [Ru]-Br is also observed in low
yield. It shows that the alkylation of 4 is not regiospe-
cific and the following Ru-N bond breaking happens.
However, the attempt at isolating the products was not
successful. In contrast to the facile alkylation of complex
4, it is surprising that there is no reaction between
complex 5 and electrophiles, which probably results
from the steric and electronic influences of the substitu-
ent at the tetrazolato ring.
Treatment of complex 3 with a 5-fold excess of
BrCH2C6F5 at room temperature for 12 h yields exclu-
sively an alkylated product {[Ru]N3(CH2C6F5)C2HCO2-
Me}[Br] (10a ) with 92% isolated yield (Scheme 3). For
the N(2)-bound triazolato complex 3, the alkylation
might have occurred at one of two nitrogens, the N(1)
nitrogen with less steric hindrance or the N(3) nitrogen
with the more nucleophilicity. From the NMR spectra
it is hard to determine the absolute structure of 10a .
To make crystals suitable for single-crystal X-ray dif-
fraction analysis, we changed the counteranion Br- to
-
BF4 . Finally, the structure of 10a was confirmed to be
a N(1)-bound N(3)-alkylated-4-methoxycarbonyl triazo-
late by an X-ray diffraction analysis. The alkylation
occurred at the more nucleophilic N(3) nitrogen atom
and transformed to a less steric hindered N(1)-bound
structure at the same time. Some regiospecific alkyla-
tions of triazoles and tetrazoles have been reported,19,47,48
but to our knowledge such an alkylation of triazolates
is the first example ever seen. Similar reactions of 3
Con clu sion s
The reaction of ruthenium azido complex [Ru]-N3 (1,
[Ru] ) (η5-C5H5)(dppe)Ru, dppe ) Ph2PCH2CH2PPh2)
and alkynes or alkenes with electron-withdrawing sub-
(48) Takash, N. E.; Holt, E. M.; Alcock, N. W.; Henry, R. A.; Nelson,
J . H. J . Am. Chem. Soc. 1980, 102, 2968.

Ruthenium Triazolato and Tetrazolato Complexes
Organometallics, Vol. 22, No. 15, 2003 3113
Syn th esis of N(2)-Bou n d Cp (d p p e)Ru N3C2(CO2Me)2
(2). To a Schlenk flask charged with 1 (222.1 mg, 0.367 mmol)
were added dimethyl acetylene dicarboxylate (234 mg, 1.65
mmol) and CH2Cl2 (20 mL). The mixture was stirred at room
temperature for 24 h then the solvent was reduced to 2 mL
under vacuum. To the residue was added 20 mL of n-hexane,
giving a yellow precipitate. After filtration, the precipitate was
washed with 2 × 10 mL of n-hexane and dried under vacuum
to give the N(2)-bound Cp(dppe)RuN3C2(CO2Me)2 (2) (245.8
mg, 0.329 mmol, 90% yield). The same product was formed by
reaction of 1 (99.8 mg, 0.165 mmol) with dimethyl fumarate
(118.9 mg, 0.825 mmol) at room temperature for one week.
The yield was 91% (111.9 mg, 0.150 mmol). Spectroscopic data
for 2 are as follows: IR (KBr, cm-1) ν(CdO) 1737 (s), 1718
(vs), ν(NdN) 1438 (s), ν(C-O) 1285 (m). 1H NMR (CDCl3) δ
7.44-7.11 (m, 20H, Ph), 4.63 (Cp), 3.62 (s, 6H, 2CH3), 3.40-
3.10, 2.70-2.40 (2m, 4H, PCH2CH2P). 31P NMR (CDCl3) δ
87.25. 13C NMR (CDCl3) δ 161.9 (CO2), 138.4 (C(CO2CH3)),
134.2-127.6 (Ph), 81.8 (Cp), 51.3 (OCH3), 28.6 (t, PCH2,
stituents yielded a series of addition products via a
[3+2] cycloaddition of a CtC or CdC bond with the
azido group. However, addition of a TCNE molecule to
1 resulted in a [3+2] cycloaddition via the CtN and
azido group and afforded a tetrazolato product. Com-
plete characterization of these triazolato and tetrazolato
complexes elucidates the structures and establishes the
N(2)-bounding type of the addition products.
Reaction of the 4,5-disubstituted 1,2,3-triazolato com-
plex 2 with organic bromides gave [Ru]-Br and a series
of 1,4,5-trisubstituted organic triazoles, N3(R)C2(CO2-
Me)2 (6a , R ) CH2C6F5; 6b, R ) CH2Ph; 6c, R ) CH2-
CO2CH3). The 4-methoxycarbonyl-1,2,3-triazolato com-
plex 3 reacts with excess methyl propiolate to give a
mixture of Z and E form zwitterionic triazolato complex
[Ru]N3(CHdCHCO2Me)C2H(CO2) (7) in a ratio of 4:1.
An organic triazole, (Z)-N3(CHdCHCO2Me)C2H(CO2-
Me), is successfully synthesized by reaction of (Z)-7 with
ICH3. A regiospecific alkylation of 3 with organic halides
yields a series of cationic N(1)-bound 3,4-disubstituted
ruthenium triazolato complexes exclusively with high
yields. The steric influences of [3+2] cycloaddition by
using the ruthenium center with different phosphine
ligand are currently under investigation. A new method
of synthesis will be developed by removing the hetero-
cyclic five-membered-ring triazolato and tetrazolato
ligands of ruthenium complexes, thus form a catalytic
cycle.
J C-P ) 21.8 Hz). MS (m/z, Ru102) 749.2 (M+), 565.1 (M+
-
N3 - 2CCO2CH3). Anal. Calcd for C37H35N3P2O4Ru: C, 59.36;
H, 4.71; N, 5.61. Found: C, 60.15; H, 4.92; N, 5.52.
Syn th esis of N(2)-Bou n d Cp (d p p e)Ru N3C2HCO2Me (3).
To a Schlenk flask charged with 1 (202.1 mg, 0.334 mmol) were
added methyl propiolate (140.1 mg, 148.2 µL, 1.668 mmol) and
CH2Cl2 (20 mL). The mixture was stirred at room temperature
for 8 h then the solvent was reduced to 2 mL under vacuum.
To the residue was added 20 mL of n-pentane, giving a yellow
precipitate. After filtration, the precipitate was washed with
2 × 10 mL of n-pentane and dried under vacuum to give the
N(2)-bound Cp(dppe)RuN3C2HCO2Me (3) (167.8 mg, 0.243
mmol, 73% yield). Spectroscopic data for 3 are as follows: IR
(KBr, cm-1) ν(CO) 1725 (vs), ν(NdN) 1438 (s), ν(C-O) 1227
Exp er im en ta l Section
1
(m). H NMR (CDCl3) δ 7.44-7.08 (m, 20H, Ph), 7.03 (s, 1H,
CH), 4.58 (Cp), 3.65 (s, 3H, CH3), 3.25-3.05, 2.70-2.50 (2m,
PCH2CH2P). 31P NMR (CDCl3) δ 88.20. 13C NMR (CDCl3) δ
162.4 (CO2), 137.7 (C(CO2CH3)), 136.2 (CH), 133.0-127.5 (Ph),
82.1 (Cp), 50.7 (OCH3), 28.9 (t, PCH2CH2P, J C-P ) 22.4 Hz).
MS (m/z, Ru102) 691.2 (M+), 565.1 (M+ - N3 - CHtCCO2CH3).
Anal. Calcd for C35H33N3O2P2Ru: C, 60.87; H, 4.82; N, 6.08.
Found: C, 61.54; H, 4.89; N, 5.96.
Gen er a l P r oced u r es. All manipulations were performed
under nitrogen with use of vacuum-line, drybox, and standard
Schlenk techniques. CH2Cl2 was distilled from CaH2 and
diethyl ether and THF from sodium diphenyketyl. All other
solvents and reagents were of reagent grade and were used
without further purification. NMR spectra were recorded on
an AM-300WB FT-NMR spectrometer at room temperature
(unless stated otherwise) and are reported in units of δ with
residual protons in the solvents as an initial standard (CDCl3,
δ 7.24: acetone-d6, δ 2.04). IR spectra were measured on a
Perkin-Elmer 983 instrument and referenced to a polystyrene
standard, using cells equipped with calcium fluoride windows.
FAB mass spectra were recorded on a J EOL SX-102A spec-
trometer. Cp(dppe)RuCl complexes were prepared following
the methods reported in the literature.49 Elemental 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 N(2)-Bou n d Cp (d p p e)Ru N3C2HCN (4). To
a Schlenk flask charged with 1 (220.5 mg, 0.364 mmol) were
added fumaronitrile (125.5 mg, 1.603 mmol) and CH2Cl2 (20
mL). The mixture was stirred at room temperature for 12 h
then the solvent was reduced to 2 mL under vacuum. To the
residue was added 20 mL of n-pentane, giving a yellow
precipitate. The precipitate was filtered, washed with 2 × 10
mL of n-pentane, and dried under vacuum to give the N(2)-
bound Cp(dppe)RuN3C2HCN (4) (198.8 mg, 0.291 mmol,
80%yield). Spectroscopic data for 4 are as follows: IR (KBr,
1
cm-1) ν(CtN) 2221 (vs), ν(NdN) 1432 (s). H NMR (CDCl3) δ
7.40-7.14 (m, 20H, Ph), 7.03 (s, 1H, CH), 4.58 (Cp), 3.20-
3.00, 2.70-2.50 (2m, PCH2CH2P). 31P NMR (CDCl3) δ 88.15.
13C NMR (CDCl3) δ 137.6 (C(CN)), 136.2 (CH), 132.8-127.7
(Ph), 113.9 (CN), 82.2 (Cp), 28.8 (t, PCH2CH2P, J C-P ) 22.3
Hz). MS (m/z, Ru102) 658.2 (M+), 565.1 (M+ - N3 - HCN). Anal.
Calcd for C34H30N4P2Ru: C, 62.10; H, 4.60; N, 8.52. Found:
C, 62.68; H, 4.73; N, 8.46.
Syn th esis of Cp (d p p e)Ru -N3 (1). To a Schlenk flask
charged with Cp(dppe)RuCl (3.03 g, 5.05 mmol) and NaN3
(1.97 g, 30.3 mmol) was added ethanol (50 mL). The resulting
solution was heated to reflux for 4 h and cooled to room
temperature. The solvent was dried under vacuum and 20 mL
of CH2Cl2 was added to the residue. The product was dissolved
in CH2Cl2 and other salts such as NaN3 and NaCl precipitated.
After filtration, the solvent was dried under vacuum to give
the product Cp(dppe)RuN3 (1; 3.03 g, 4.99 mmol, 99% yield).
Spectroscopic data for 1 are as follows: IR (KBr, cm-1) ν(N3)
2018 (vs). 1H NMR (CDCl3) δ 7.82-7.18 (m, 20H, Ph), 4.47
(Cp), 2.80-2.30 (m, 4H, PCH2). 31P NMR (CDCl3) δ 81.52. 13C
NMR (CDCl3) δ 133.6-127.9 (Ph), 79.9 (Cp), 27.7 (t, PCH2,
J C-P ) 22.4 Hz). MS (m/z, Ru102) 607.3 (M+), 579.2 (M+ - N2),
565.2 (M+ - N3). Anal. Calcd for C31H29N3P2Ru: C, 61.38; H,
4.82; N, 6.93. Found: C, 61.83; H, 4.91; N, 6.82.
Syn t h esis of N(2)-Bou n d Cp (d p p e)R u N4C[C(CN)C-
(CN)2] (5). To a Schlenk flask charged with 1 (200.5 mg, 0.331
mmol) and TCNE (200.9 mg, 1.570 mmol) was added CH2Cl2
(20 mL). The mixture was stirred at room temperature for 24
h then the solvent was reduced to 2 mL under vacuum. To
the residue was added 20 mL of n-hexane. After filtration, the
deep-blue precipitate was washed with 2 × 10 mL of n-hexane
and dried under vacuum to give the N(2)-bound Cp(dppe)-
RuN4C[C(CN)C(CN)2] (5) (193.6 mg, 0.264 mmol, 80% yield).
Spectroscopic data for 5 are as follows: IR (KBr, cm-1
)
ν(CtN) 2228 (s), 2196 (m), ν(NdN) 1432 (vs). 1H NMR (CDCl3)
δ 7.59-7.13 (m, 20H, Ph), 4.76 (Cp), 3.30-3.10, 2.70-2.50 (2m,
(49) Bressan, M.; Rigo, P. Inorg. Chem. 1975, 14, 2286.

3114 Organometallics, Vol. 22, No. 15, 2003
Chang and Lee
4H, PCH2CH2P). 31P NMR (CDCl3) δ 86.97. 13C NMR (CDCl3)
δ 154.9 (C(CN)2), 140.8 (C(CN)), 133.1-128.1 (Ph), 126.1
(CdN), 112.0, 111.8, 110.9 (CN), 82.9 (Cp), 28.5 (t, PCH2,
Syn t h esis of N(1)-Bou n d (Z)-{Cp (d p p e)R u -N3(CH d
CHCO2Me)C2H(CO2Me)}[I] (8a ) a n d (Z)-{Cp (d p p e)Ru -N3-
(CHdCHCO2Me)C2H(CO2C6F 5)}[Br ] (8b). To a Schlenk
flask charged with (Z)-7 (85.1 mg, 0.112 mmol) and ICH3 (35
µL, 0.560 mmol) was added CH2Cl2 (20 mL). The resulting
solution was stirred at room temperature for 24 h, then the
solvent was reduced to 2 mL under vacuum. To the residue
was added 20 mL of diethyl ether. The yellow precipitate thus
formed was filtered, washed with 2 × 10 mL of diethyl ether,
and dried under vacuum to give the N(1)-bound (Z)-{Cp(dppe)-
RuN3(CHdCHCO2Me)C2H(CO2Me)}[I] (8a ) (90.9 mg, 0.101
mmol) in 90% yield. Spectroscopic data for 8a are as follows:
IR (KBr, cm-1) ν(CdO) 1731 (vs), 1720 (vs), ν(NdN) 1438 (vs),
J C-P ) 21.9 Hz). MS (m/z, Ru102) 735.1 (M+), 565.1 (M+
-
N3 - C2(CN)4). Anal. Calcd for C37H29N7P2Ru: C, 60.49; H,
3.98; N, 13.35. Found: C, 61.63; H, 3.79; N, 13.47.
Syn th esis of N3(CH2C6F 5)C2(CO2Me)2 (6a ) a n d Oth er
Or ga n ic Tr ia zoles. To a Schlenk flask charged with 2 (200.1
mg, 0.268 mmol) and BrCH2C6F5 (140 mg, 1.34 mmol) was
added CH2Cl2 (20 mL). The resulting solution was stirred at
about 40 °C for 48 h then the solvent was dried under vacuum.
To the residue was added 10 mL of cold n-pentane. After
filtration, the orange precipitate was washed with 2 × 10 mL
of n-pentane and dried under vacuum to give the product Cp-
(dppe)RuBr (169.3 mg, 0.263 mmol, 98% yield). The filtrate
was dried and extracted with 2 × 10 mL of cold n-pentane.
The extract was filtered and the filtrate was dried under
vacuum to give a mixture of the organic triazole N3(CH2C6-
F5)C2(CO2Me)2 (6a ) and the excess BrCH2C6F5. Spectroscopic
data for Cp(dppe)RuBr are as follows: 1H NMR (CDCl3) δ
7.85-7.09 (m, 20H, Ph), 4.56 (Cp), 2.80-2.60, 2.50-2.30 (2m,
PCH2CH2P). 31P NMR (CDCl3) δ 79.86. 13C NMR (CDCl3) δ
133.9-127.8 (Ph), 79.8 (Cp), 27.1 (t, PCH2, J C-P ) 13.6 Hz).
MS (m/z, Ru,102 Br81) 646.1 (M+), 565.2 (M+ - Br). Anal. Calcd
for C31H29P2RuBr: C, 57.77; H, 4.54. Found: C, 58.02; H, 4.64.
Spectroscopic data for 6a are as follows: 1H NMR (CDCl3) δ
5.86 (s, 2H, CH2), 3.98, 3.88 (s, 3H, OCH3). 13C NMR (CDCl3)
δ 160.1, 158.6 (CO2), 140.1, 132.0 (C(CO2CH3)), 146.0-136.4
(Ph), 53.6, 52.8 (OCH3), 41.3 (CH2). MS (m/z) 366.1 (M++ 1).
Complexes N3(CH2Ph)C2(CO2Me)2 (6b ) and N3(CH2CO2Me)-
C2(CO2Me)2 (8c) were prepared with similar procedure as that
of 6a . Spectroscopic data for 6b are as follows: 1H NMR
(CDCl3) δ 7.84-7.11 (m, 5H, Ph), 5.80 (s, 2H, CH2), 3.98, 3.88
(s, 3H, CH3). 13C NMR (CDCl3) δ 160.3, 158.7 (CO2), 140.1,
133.8 (C(CO2CH3)), 137.9-127.8 (Ph), 53.8, 52.6 (OCH3), 53.2
(CH2). MS (m/z) 276.1 (M+ + 1). Spectroscopic data for 6c are
as follows: 1H NMR (CDCl3) δ 5.42 (s, 2H, CH2), 3.94, 3.92,
3.87 (s, 3H, OCH3). 13C NMR (CDCl3) δ 168.6, 164.4, 156.0
(CO2), 143.8, 132.1 (C(CO2CH3)), 53.3, 52.7, 52.3 (OCH3), 51.3
(CH2). MS (m/z) 258.1 (M+ + 1).
1
ν(C-O) 1228 (m). H NMR (CDCl3) δ 7.67 (s, 1H, CH), 7.50-
7.21 (m, 20H, Ph), 6.68 (d, 1H, J H-H ) 9.23 Hz, CHdCHCO2),
5.84 (d, 1H, J H-H ) 9.23 Hz, CHdCHCO2), 4.74 (Cp), 3.94,
3.57 (s, 3H, OCH3), 2.95, 2.66 (m, 2H, PCH2). 31P NMR (CDCl3)
δ 84.45. 13C NMR (CDCl3) δ 162.4, 156.3 (CO2), 144.3 (CH),
139.1-128.6 (Ph, CCO2, CHdCHCO2), 119.3 (CHdCHCO2),
82.2 (Cp), 53.2, 52.0 (OCH3), 29.0 (t, PCH2CH2P, J C-P ) 22.5
Hz). MS (m/z, Ru102) 776.2 (M+ - I), 565.1 (M+ - triazolato
ring). Anal. Calcd for C39H38N3P2O4RuI: C, 51.89; H, 4.24; N,
4.66. Found: C, 51.11; H, 4.46; N, 4.38. Complex (Z)-{Cp(dppe)-
Ru-N3(CHdCHCO2Me)C2H(CO2C6F5)}[Br] (8b) (91.7 mg, 0.090
mmol, 85% yield from 80.3 mg of (Z)-7) was prepared by using
a similar procedure as that of 8a . Spectroscopic data for 8b
are as follows: 1H NMR (CDCl3) δ 7.50 (s, 1H, CH), 7.71-
7.19 (m, 20H, Ph), 6.45 (d, 1H, J H-H ) 9.42 Hz, CHdCHCO2),
5.76 (d, 1H, J H-H ) 9.42 Hz, CHdCHCO2), 5.29 (s, 2H, CH2),
4.70 (Cp), 3.54 (s, 3H, OCH3), 2.86, 2.60 (m, 2H, PCH2). 31P
NMR (CDCl3) δ 84.00. 13C NMR (CDCl3) δ 162.3, 155.3 (CO2),
144.0 (CH), 139.0-128.0 (Ph, CCO2, CHdCHCO2), 119.4 (CHd
CHCO2), 82.1 (Cp), 54.8 (CH2), 52.3 (OCH3), 28.6 (t, PCH2-
CH2P, J C-P ) 22.6 Hz). MS (m/z, Ru102) 942.2 (M+ - Br), 565.1
(M+ - triazolato ring). Anal. Calcd for C45H37N3P2O4RuF5Br:
C, 52.90; H, 3.65; N, 4.11. Found: C, 51.78; H, 3.83; N, 3.97.
Syn t h esis of (Z)-N3(CH dCHCO2Me)C2H(CO2Me) (9a )
an d (Z)-N3(CHdCHCO2Me)C2H(CO2C6F5) (9b). To a Schlenk
flask charged with (Z)-7 (200.1 mg, 0.263 mmol) were added
CH2Cl2 (20 mL) and ICH3 (164 µL, 2.635 mmol). The resulting
solution was stirred for 4 days at room temperature, then the
solvent and ICH3 were dried under vacuum. The residue was
extracted with 2 × 10 mL of cold n-pentane. The extract was
filtered and the filtrate was dried under vacuum to give a
colorless liquid, (Z)-N3(CHdCHCO2Me)C2H(CO2Me) (9a )
(19.4 mg, 0.092 mmol, 35% yield). Spectroscopic data for 9a
are as follows: 1H NMR (CDCl3) δ 8.14 (s, 1H, CH), 7.62 (d,
1H, J H-H ) 9.29 Hz, CHdCHCO2), 6.14 (d, 1H, J H-H ) 9.29
Hz, CHdCHCO2), 3.92, 3.70 (OCH3). 13C NMR (CDCl3) δ 165.5,
152.3 (CO2), 137.3 (CH), 129.4 (CCO2), 118.3 (CHdCHCO2),
106.2 (CHdCHCO2), 52.8, 52.2 (OCH3). High-resolution MS
(m/z): calcd for C8H9N3O4 211.0591, found 211.0593. Complex
(Z)-N3(CHdCHCO2Me)C2H(CO2C6F5) (9b) was prepared from
(Z)-7 with a 10-fold excess of BrCH2C6F5 with use of a similar
procedure as that of 9a . The final product is still mixed with
excess BrCH2C6F5. Spectroscopic data for 9b are as follows:
1H NMR (CDCl3) δ 8.16 (s, 1H, CH), 7.58 (d, 1H, J H-H ) 9.46
Hz, CHdCHCO2), 6.15 (d, 1H, J H-H ) 9.46 Hz, CHdCHCO2),
5.48 (OCH2), 3.84 (s, 3H, OCH3). 13C NMR (CDCl3) δ 165.3,
157.3 (CO2), 146.0, 142.7, 138.6, 136.6 (m, C6F5), 137.5 (CH),
129.4 (CCO2), 118.8 (CHdCHCO2), 114.5 (CHdCHCO2), 52.3
(OCH2), 52.2 (OCH3).
Syn th esis of N(1)-Bou n d Cp (d p p e)Ru N3(CHdCHCO2-
Me)CHC(CO2) (7). To a Schlenk flask charged with 1 (500.2
mg, 0.825 mmol) were added methyl propiolate (732 µL, 8.255
mmol) and CHCl3 (25 mL). The mixture was stirred at room
temperature for 5 days then the solvent was reduced to 2 mL
under vacuum. To the residue was added 20 mL of n-pentane,
giving a yellow precipitate. After filtration, the precipitate was
washed with 2 × 10 mL of n-pentane and dried under vacuum
to give a mixture of N(1)-bound (Z)- and (E)-Cp(dppe)-
RuN3(CHdCHCO2Me)CHC(CO2) (7) (533.7 mg, 0.701 mmol,
85% yield, (Z)-7:(E)-7 ) 4:1). Spectroscopic data for (Z)-7 are
as follows: IR (KBr, cm-1) ν(CdO) 1731 (vs), ν(COO-) 1636
1
(vs), ν(NdN) 1432 (vs), ν(C-O) 1228 (m). H NMR (CDCl3) δ
7.59-7.13 (m, 21H, Ph and CH), 7.57 (d, 1H, J H-H ) 10.31
Hz, CHdCHCO2), 5.42 (d, 1H, J H-H ) 10.31 Hz, CHdCHCO2),
4.59 (Cp), 3.46 (s, 3H, CH3), 2.91, 2.62 (m, 2H, PCH2). 31P NMR
(CDCl3) δ 86.16. 13C NMR (CDCl3) δ 163.8, 158.2 (CO2), 143.4
(CH), 140.6-128.5 (Ph, CCO2, CHdCHCO2), 112.1 (CHd
CHCO2), 82.4 (Cp), 51.4 (OCH3), 28.7 (t, PCH2CH2P, J C-P
)
-
22.5 Hz). MS (m/z, Ru102) 762.2 (M+ + 1), 565.1 (M+
triazolato ring). Anal. Calcd for C38H35N3O4P2Ru: C, 60.00;
H, 4.64; N, 5.52. Found: C, 59.17; H, 4.87; N, 5.23. Spectro-
scopic data for (E)-7 are as follows: 1H NMR (CDCl3) δ 8.65
(d, 1H, J H-H ) 14.32 Hz, CHdCHCO2), 7.87 (s, 1H, CH), 7.59-
7.13 (m, 20H, Ph), 4.95 (d, 1H, J H-H ) 14.32 Hz, CHdCHCO2),
4.62 (Cp), 3.64 (s, 3H, CH3), 2.91, 2.62 (m, 2H, PCH2). 31P NMR
(CDCl3) δ 85.76. 13C NMR (CDCl3) δ 165.4, 157.9 (CO2), 144.6
(CH), 139.7-128.2 (Ph, CCO2, CHdCHCO2), 110.6 (CHd
Syn th esis of N(1)-Bou n d {Cp (d p p e)Ru N3(CH2C6F 5)-
C2HCO2Me}[Br ] (10a ) a n d Oth er Tr ia zola to Com p lexes.
To a Schlenk flask charged with 3 (100.1 mg, 0.145 mmol) and
BrCH2C6F5 (109.4 µL, 0.724 mmol) was added CH2Cl2 (20 mL).
The resulting solution was stirred at room temperature for
24 h, then the solvent was reduced to 2 mL under vacuum. To
the residue was added 20 mL of n-pentane. The yellow
precipitate thus formed was filtered, washed with 2 × 10 mL
of n-pentane, and dried under vacuum to give the N(1)-bound
CHCO2), 82.2 (Cp), 51.7 (OCH3), 27.7 (t, PCH2CH2P, J C-P
23.4 Hz). MS (m/z, Ru102) 762.1 (M+ + 1), 565.1 (M+
triazolato ring).
)
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Ruthenium Triazolato and Tetrazolato Complexes
Organometallics, Vol. 22, No. 15, 2003 3115

3116 Organometallics, Vol. 22, No. 15, 2003
Chang and Lee
{Cp(dppe)RuN3(CH2C6F5)C2HCO2Me}[Br] (10a ) (126.9 mg,
0.133 mmol) in 92% yield. Spectroscopic data for 10a are as
follows: IR (KBr, cm-1) ν(CdO) 1738 (vs), ν(NdN) 1438 (vs),
and CCO2), 82.1 (Cp), 53.2 (OCH3), 37.4 (NCH3), 29.0 (t, PCH2,
J C-P ) 22.6 Hz). MS (m/z, Ru102) 706.1 (M+ - I), 565.0 (M+
-
I - CH3 - N3 - C2HCO2CH3). Anal. Calcd for C36H36N3P2O2-
RuI: C, 51.93; H, 4.36; N, 5.05. Found: C, 51.63; H, 4.54; N,
4.92.
1
ν(C-O) 1222 (m). H NMR (CDCl3) δ 8.43 (s, 1H, CH), 7.67-
7.06 (m, 20H, Ph), 4.97 (s, 2H, CH2), 4.62 (Cp), 3.96 (s, 3H,
OCH3), 2.74, 2.71 (2 br, 4H, PCH2CH2P). 31P NMR (CDCl3) δ
86.23. 13C NMR (CDCl3) δ 157.0 (CO2), 146.0 (CH), 140.1-
128.3 (Ph and C(CO2)), 82.6 (Cp), 53.4 (OCH3), 39.4 (CH2), 28.9
X-r a y An a lysis. Single crystals suitable for X-ray diffrac-
tion study were grown as mentioned above. The chosen single
crystal was glued to a glass fiber and mounted on a SMART
CCD or a CAD4 diffractometer. The data were collected with
use of 3-kW sealed-tube molybdenum KR radiation (λ ) 0.7107
Å). Intensity was intergrated and absorption corrections were
applied by using SADABS.50 Data were processed and refined
by using the SHELXTL51 program. Hydrogen atoms were
placed geometrically, using the riding model with thermal
parameters set to 1.2 times that for the atoms to which the
hydrogen is attached and 1.5 times that for the methyl
hydrogens. Crystal data for 2, 3, 4, 5, (Z)-7, and 10a are listed
in Table 5. Final values of all refined atomic positional
parameters (with esd’s) and tables of thermal parameters are
given in the Supporting Information.
(t, PCH2CH2P, J C-P ) 22.3 Hz). MS (m/z, Ru102) 872.0 (M+
-
Br), 565.0 (M+ - Br - CH2C6F5 - N3 - C2HCO2CH3). Anal.
Calcd for C42H35N3P2O2RuF5Br: C, 53.01; H, 3.71; N, 4.42.
Found: C, 54.11; H, 3.80; N, 4.39. Complex {Cp(dppe)-
RuN3(CH2Ph)C2HCO2Me}[Br] (10b) (108.7 mg, 0.126 mmol,
87% yield from 100.2 mg of 3), {Cp(dppe)RuN3(CH2CO2Me)-
C2HCO2Me}[Br] (10c) (109.9 mg, 0.130 mmol, 90% yield from
100.0 mg of 3), and {Cp(dppe)RuN3(CH3)C2HCO2Me}[I] (10d )
(102.4 mg, 0.123 mmol, 83% yield from 102.3 mg of 3) were
prepared by using a similar procedure as that of 10a . Spec-
troscopic data for 10b are as follows: 1H NMR (CDCl3) δ 8.34
(s, 1H, CH), 7.41-7.09 (m, 25H, Ph), 4.85 (s, 2H, CH2), 4.70
(Cp), 3.83 (s, 3H, CH3), 2.76-2.64 (m, 4H, PCH2CH2P). 31P
NMR (CDCl3) δ 85.84. 13C NMR (CDCl3) δ 156.6 (CO2), 146.2
(CH), 139.6-126.7 (Ph and C(CO2)), 82.1 (Cp), 53.6 (CH2), 53.1
(OCH3), 28.7 (t, PCH2, J C-P ) 23.8 Hz). MS (m/z, Ru102) 782.1
(M+ - Br), 565.0 (M+ - Br - CH2Ph - N3 - C2HCO2CH3).
Anal. Calcd for C42H40N3P2O2RuBr: C, 58.54; H, 4.68; N, 4.88.
Found: C, 59.13; H, 4.77; N, 4.78. Spectroscopic data for 10c
are as follows: 1H NMR (CDCl3) δ 8.05 (s, 1H, CH), 7.80-
7.06 (m, 25H, Ph), 4.70 (Cp), 4.44 (s, 2H, CH2), 3.85, 3.51 (s,
3H, CH3), 3.00-2.60 (m, 4H, PCH2). 31P NMR (CDCl3) δ 84.43.
13C NMR (CDCl3) δ 164.5, 156.6 (CO2), 145.1 (CH), 139.0-
127.6 (Ph and C(CO2)), 81.9 (Cp), 53.2, 52.9 (OCH3), 50.6 (CH2),
Ack n ow led gm en t. We are grateful for support of
this work by Dr. Ying-Chih Lin, Department of Chem-
istry, National Taiwan University and the National
Science Council, Taiwan, Republic of China and helpful
discussions of Dr. Yu Wang, Department of Chemistry,
National Taiwan University.
Su p p or tin g In for m a tion Ava ila ble: Details about the
X-ray crystal structures, including diagrams, and the tables
of crystal data and structure refinement, atomic coordinates,
bond lengths and angles, and anisotropic displacement pa-
rameters for 2, 3, 4, 5, (Z)-7 and 10a . This material is available
free of charge via the Internet at http://pubs.acs.org.
28.4 (t, PCH2, J C-P ) 21.0 Hz). MS (m/z, Ru102) 764.1 (M+
-
Br), 565.0 (M+ - Br - CH2CO2CH3 - N3 - C2HCO2CH3). Anal.
Calcd for C38H38N3P2O2RuBr: C, 54.10; H, 4.54; N, 4.98.
Found: C, 53.87; H, 4.63; N, 4.85. Spectroscopic data for 10d
are as follows: 1H NMR (CDCl3) δ 8.18 (s, 1H, CH), 7.83-
7.06 (m, 25H, Ph), 4.76 (Cp), 3.88 (s, 3H, CH3), 3.26 (s, 3H,
NCH3), 2.97, 2.67 (m, 2H, PCH2). 31P NMR (CDCl3) δ 84.90.
13C NMR (CDCl3) δ 156.8 (CO2), 145.8 (CH), 134.1-127.7 (Ph
OM030079R
(50) The SADABS program is based on the method of Blessing;
see: Blessing, R. H. Acta Crystallogr., Sect. A 1995, 51, 33.
(51) SHELXTL: Structure Analysis Program, version 5.04; Siemens
Industrial Automation Inc.: Madison, WI, 1995.