Phosphorane Migration from Ruthenium to the Cyclopentadienyl Ring

Article abstract of DOI:10.1021/om9904145

Ruthenium phosphorane complexes, Cp(CO)₂Ru{P(OC₆H₄Z)₂} (Z = NMe, O), react with lithium diisopropylamide (LDA) to give Li[{η⁵-C₅H₄P(OC₆H ₄Z)₂}(CO)₂Ru] (5). In this reaction, one of the protons on the Cp ring is abstracted by LDA and then migration of the phosphorane fragment to the Cp ring takes place. Treatment of 5 with RX (CH₃I, PhCH₂Cl, Ph₃SnCl, HOCOCF₃, CD₃I) yields {η⁵-C₅H₄P(OC₆H ₄Z)₂}(CO)₂RuR (2). The structure of one of the products, {η⁵-C₆H₄P(OC₆H ₄NMe)₂}(CO)₂RuCH₂Ph, was determined by X-ray analysis. A reaction of a cationic phosphite complex, [Cp(CO)₂Ru{P(OC₆H₄NMe)(OC₆H ₄NMeH)}]BF₄ (6), with 2 equiv of LDA also gives 5. However, the following addition of RX at -30°C gives the unexpected phosphorane-migration complex {η⁵-C₅H₄P(OC₆H ₄NMe)₂}(CO)₂RuR, which contains one O atom and one N atom in apical positions and in equatorial positions as well. The complex gradually isomerizes to a thermally more stable apical oxygen-equatorial nitrogen isomer (2).

Full text of DOI:10.1021/om9904145

4518
Organometallics 1999, 18, 4518-4523
P h osp h or a n e Migr a tion fr om Ru th en iu m to th e
Cyclop en ta d ien yl Rin g
Hiroshi Nakazawa,* Kazumori Kawamura, Kazuyuki Kubo, and
Katsuhiko Miyoshi*
Department of Chemistry, Graduate School of Science, Hiroshima University,
Higashi-Hiroshima 739-8526, J apan
Received J une 1, 1999
Ruthenium phosphorane complexes, Cp(CO)2Ru{P(OC6H4Z)2} (Z ) NMe, O), react with
lithium diisopropylamide (LDA) to give Li[{η5-C5H4P(OC6H4Z)2}(CO)2Ru] (5). In this reaction,
one of the protons on the Cp ring is abstracted by LDA and then migration of the phosphorane
fragment to the Cp ring takes place. Treatment of 5 with RX (CH3I, PhCH2Cl, Ph3SnCl,
HOCOCF3, CD3I) yields {η5-C5H4P(OC6H4Z)2}(CO)2RuR (2). The structure of one of the
products, {η5-C5H4P(OC6H4NMe)2}(CO)2RuCH2Ph, was determined by X-ray analysis. A
reaction of a cationic phosphite complex, [Cp(CO)2Ru{P(OC6H4NMe)(OC6H4NMeH)}]BF4 (6),
with 2 equiv of LDA also gives 5. However, the following addition of RX at -30 °C gives the
unexpected phosphorane-migration complex {η5-C5H4P(OC6H4NMe)2}(CO)2RuR, which con-
tains one O atom and one N atom in apical positions and in equatorial positions as well.
The complex gradually isomerizes to a thermally more stable apical oxygen-equatorial
nitrogen isomer (2).
In tr od u ction
hypervalent fragment migration. We also reported
syntheses and structures of ruthenium-phosphorane
complexes.15 This paper reports the second example of
a hypervalent fragment migration: that is, a phospho-
rane migration for Cp(CO)2Ru{P(OC6H4Z)2} (Cp ) η5-
C5H5; Z ) NMe, O) (Although the complex should be
The formation and structure of hypervalent com-
pounds of main-group elements continue to be an area
of lively interest, and the results have been reviewed.1-9
Their reactivities have also been investigated.4,7-12
However, migration of a hypervalent fragment13 has not
been reported for any kind of hypervalent element.
Recently we reported base-induced migration of a phos-
phorane fragment from iron to the cyclopentadienyl ring
described as Cp(CO)2Ru{P(OC6H4Z)2}, the tie line is
omitted for this type of complex in this paper for clarity.)
The migration involves some interesting findings which
have not been observed in the case of the related iron
complexes.
in Cp(CO)2Fe{P(OC6H4Y)(OC6H4Z)}14 (Cp ) η5-C5H5; Y,
Z ) NMe, NH, O). This is the first example of a
Resu lts a n d Discu ssion
(1) Holmes, R. R. Acc. Chem. Res. 1979, 12, 257.
(2) Martin, J . C. Science 1983, 221, 509.
Reaction s of [Cp(CO)2Ru {P (OC6H4Z)2}] with LDA
a n d Th en RX. The reaction procedures and character-
ization of the product are described with Cp(CO)2Ru-
{P(OC6H4NMe)2] (1) as an example. Treatment of a
yellow solution of 1 with 1 equiv of freshly prepared
lithium diisopropylamide (LDA) at -78 °C in THF gave
an orange solution. Successive addition of MeI gave a
pale yellow suspension from which a white powder was
obtained by purification using a silica gel column. For
the following reasons, we concluded that a migration
product of a phosphorane fragment to a Cp ligand (2a )
was obtained. (i) The 31P NMR spectrum exhibits a
singlet at -47.27 ppm, which is ca. 40 ppm higher in
magnetic field than that of 1. (ii) The 1H NMR spectrum
shows a multiplet pattern and the 13C NMR spectrum
(3) Niedenzu, K.; Trofimenco, S.; Heller, G.; Tandura, St. N.;
Alekseev, N. V.; Voronkov, M. G. In Topics in Current Chemistry;
Boschke, F. L., Ed.; Springer-Verlag: Berlin, 1986; Vol. 131.
(4) Chuit, C.; Corriu, R. J . P.; Reye, C.; Young, J . C. Chem. Rev.
1993, 93, 1371.
(5) Gilheany, D. G. In The Chemistry of Organophosphorus Com-
pounds; Hartley, F. R., Ed.; Wiley: West Sussex, U.K., 1994; Chapter
1. Burgada, R.; Setton, R. Ibid., Chapter 3.
(6) Ramsden, C. A. Chem. Soc. Rev. 1994, 23, 111.
(7) Dillon, K. B. Chem. Rev. 1994, 94, 1441.
(8) Holmes, R. R. Chem. Rev. 1996, 96, 927.
(9) Stang, P. J .; Zhdankin, V. V. Chem. Rev. 1996, 96, 1123.
(10) Barton, D. H. R. In Heteroatom Chemistry; Block, E., Ed.;
VCH: New York, 1990; Chapter 5. Furukawa, N. Ibid., Chapter 9.
Seppelt, K. Ibid., Chapter 19.
(11) (a) Oae, S. Pure Appl. Chem. 1996, 68, 805. (b) Oae, S. Main
Group Chem. News 1996, 4, 10.
(12) Kita, Y.; Takada, T.; Tohma, H. Pure Appl. Chem. 1996, 68,
627.
(13) In this paper, we use the term “hypervalent fragment” for the
group of a central element with at least one 3c-4e bond (hypervalent
bond).
(14) Kubo, K.; Nakazawa, H.; Kawamura, K.; Mizuta, T.; Miyoshi,
K. J . Am. Chem. Soc. 1998, 120, 6715.
(15) Nakazawa, H.; Kawamura, K.; Kubo, K.; Miyoshi, K. Organo-
metallics 1999, 18, 2961.
10.1021/om9904145 CCC: $18.00 © 1999 American Chemical Society
Publication on Web 10/03/1999

Phosphorane Migration from Ruthenium
Organometallics, Vol. 18, No. 22, 1999 4519
exhibits five doublets in the Cp region, suggesting that
the product has a phosphorus-substituted Cp ligand. (iii)
A singlet is observed at 0.27 ppm in the 1H NMR
spectrum and a singlet at -31.64 ppm in the 13C NMR
spectrum, indicating that a methyl group is bonded to
the ruthenium atom. (iv) In the IR spectrum, two
absorption bands due to νCO are observed at 2020 and
1959 cm-1. These spectroscopic features are very similar
to those for the corresponding iron complex.14
The reaction of 1 with LDA and then PhCH2Cl, Ph3-
SnCl, HOCOCF3, and CD3I in place of CH3I gave 2b-d
and 2a -d 3, respectively (eq 1). The formation of 2a -d 3
F igu r e 1. ORTEP drawing of 2b (50% probability el-
lipsoids) showing the numbering system. All hydrogen
atoms are omitted for clarity.
Ta ble 1. Su m m a r y of Cr ysta l Da ta for 2b
formula
fw
C28H25N2O4PRu
585.56
cryst syst
space group
cell constants
a, Å
monoclinic
P21/c
10.753(3)
b, Å
29.180(7)
c, Å
8.015(3)
â, deg
94.32(3)
2508(1)
V, Å3
Z
D
4
1.70
7.11
calcd, g cm-3
µ, cm-1
cryst size, mm
radiation
0.62 × 0.27 × 0.12
clearly demonstrates that the methyl group on Ru for
2a comes from added MeI, not from the NMe group in
the phosphorane fragment. The structure of 2b was
confirmed by an X-ray analysis (vide infra). These
complexes correspond to the migration products of a
phosphorane fragment from a ruthenium atom to the
Cp ring. The reaction of 3, having four O and one Ru
atoms on the hypervalent phosphorus, with LDA and
then MeI also led to the formation of the phosphorane-
migration product 4. These results show that the
phosphorane migration reaction seems to be general.
Diastereotopic â- and γ-carbon resonances in the Cp ring
in the 13C NMR spectra were observed for complexes 2,
whereas 4 did not show such resonances. Therefore,
Berry pseudorotation may be slower for complexes 2, if
it occurs at all, whereas it does occur faster for 4 than
the NMR time scale. This tendency is the same as that
exhibited by the corresponding iron complexes.14
Cr ysta l Str u ctu r e of 2b. The structure of 2b was
determined by X-ray diffraction analysis. The ORTEP
drawing is displayed in Figure 1. The crystal data and
the selected bond distances and angles are summarized
in Tables 1 and 2, respectively.
Mo KR (λ ) 0.710 73 Å)
scan technique
scan range, deg
scan rate, deg min-1
no. of unique data
no. of unique data, Fo > 3σ(Fo)
R
ω
3 < 2θ < 53
6.0
5122
3662
0.034
0.037
Rw
a monosubstituted Cp ligand in an η5 fashion, two
terminal CO ligands, and a benzyl ligand. The geometry
around the phosphorus atom is almost trigonal bipyra-
midal with two oxygens in the apical positions and with
two nitrogens and one carbon in the equatorial posi-
tions: P1, N1, N2, and C10 make a plane (the sum of
the angles around P1 is 360.0°), and the O3-P1-O4
angle is 179.0°. Comparison of the structures of 115 and
2b reveals that the P-O bond is ca. 0.05 Å shorter and
the P-N bond is ca. 0.02 Å shorter for 2b than for 1.
This tendency has been observed in the corresponding
iron case.14 The bond distances and the bond angles
around the phosphorane phosphorus for 2b are almost
the same as those for the corresponding iron complex
{C5H4P(OC6H4NMe)2}Fe(CO)2(CH2Ph).14 The apical axis
(O3-P1-O4) is slightly tilted from the Cp plane. The
torsion angles (O4-P1-C10-C11 ) 28.2°, O3-P1-
C10-C14 ) 33.1°) are also similar to those of the
The X-ray structure clearly shows that 2b is a
migration product of a phosphorane fragment from Ru
to the Cp ring. The ruthenium atom is coordinated by

4520 Organometallics, Vol. 18, No. 22, 1999
Nakazawa et al.
Ta ble 2. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for 2b
Sch em e 1
Bond Distances
Ru1-C1
Ru1-C2
Ru1-C3
P1-O3
P1-O4
P1-N1
P1-N2
P1-C10
O1-C1
O2-C2
O3-C15
O4-C22
1.856(3)
1.852(3)
2.184(3)
1.709(2)
1.713(2)
1.694(3)
1.704(2)
1.799(3)
1.139(4)
1.147(4)
1.365(3)
1.374(3)
N1-C20
N1-C21
N2-C27
N2-C28
C3-C4
C10-C11
C10-C14
C11-C12
C12-C13
C13-C14
C15-C20
C22-C27
1.406(4)
1.452(5)
1.398(3)
1.467(4)
1.487(4)
1.431(4)
1.453(4)
1.424(4)
1.428(4)
1.394(5)
1.385(4)
1.396(4)
Bond Angles
C1-Ru1-C2
C1-Ru1-C3
C2-Ru1-C3
O3-P1-O4
O3-P1-N1
O3-P1-N2
O3-P1-C10
O4-P1-N1
O4-P1-N2
O4-P1-C10
N1-P1-N2
N1-P1-C10
N2-P1-C10
P1-O3-C15
P1-O4-C22
P1-N1-C20
P1-N1-C21
C20-N1-C21
89.5(2)
89.7(2)
87.4(2)
179.0(1)
89.0(1)
90.7(1)
90.5(1)
90.3(1)
89.1(1)
90.4(1)
124.8(2)
116.9(1)
118.3(1)
114.3(2)
114.5(2)
113.9(2)
128.7(3)
117.1(3)
P1-N2-C27
P1-N2-C28
C27-N2-C28
Ru1-C1-O1
Ru1-C2-O2
Ru1-C3-C4
P1-C10-C11
P1-C10-C14
C11-C10-C14
C10-C11-C12
C11-C12-C13
C12-C13-C14
C10-C14-C13
O3-C15-C20
N1-C20-C15
O4-C22-C27
N2-C27-C22
113.5(2)
128.8(2)
117.3(2)
177.0(3)
177.3(2)
112.9(2)
127.1(2)
127.0(2)
105.8(2)
109.3(3)
106.9(3)
109.1(3)
108.8(3)
112.0(3)
110.4(3)
110.9(2)
111.4(2)
corresponding iron complex. These results indicate that
the geometry around the phosphorane phosphorus is not
affected by whether a transition metal is Ru or Fe.
Ch a r t 1
Con sid er a tion of P h osp h or a n e F r a gm en t Mi-
gr a tion P r ocess. To elucidate the migration process,
we examined the product in the reaction of 1 with LDA.
Although the several attempts to isolate the product
were unsuccessful due to its instability, the spectro-
scopic data of the reaction mixture enabled us to identify
the product (5) as shown in Scheme 1.
(s), 1801 (m), and 1759 (m) cm-1. The pattern is very
close to that for the Fe and Os complexes. From an
interpretation of the precedents,16,17 absorptions at 1907
and 1826 cm-1 can be assigned to the Ru‚‚‚Li contact
ion pair (A), those at 1889 and 1759 cm-1 to the Ru-
CO‚‚‚Li ion pair (B), and those at 1889 and 1801 cm-1
to the solvent-separated ion pair (C). The IR absorption
bands for 5 also resemble those for Li[Cp(CO)2Ru].
Therefore, it may be reasonable that absorptions at 1916
and 1836 cm-1 are assigned to A, those at 1898 and
1775 cm-1 to B, and those at 1898 and 1815 cm-1 to C.
It should be noted here that the Ru‚‚‚Li contact ion pair
is a dominant species, as judged from their relative
intensities.
The IR spectrum shows 5 absorption bands in the νCO
region (1916 (s), 1898 (s), 1836 (s), 1815 (m), 1775 (m)
cm-1). These values are more than 120 cm-1 lower in
frequency than those for 1, indicating a formation of an
anionic ruthenium complex, [(η5-C5H4{P(OC6H4NMe)2})-
(CO)2Ru]-. In the case of M′[(η5-C5R5)(CO)2M] (R ) H:
M′ ) Li, Na, K: M ) Fe;16 R ) Me: M′ ) Li: M ) Os17),
it has been proposed that each complex exists as a
mixture containing three kinds of ion pairs, an M‚‚‚M′
contact ion pair (A), an M-CO‚‚‚M′ ion pair with a
metal carbonyl oxygen interaction (B), and a solvent-
separated ion pair (C) (see Chart 1). However, there is
no report about a ruthenium analogue.18 Thus, we
prepared Li[Cp(CO)2Ru] from Cp(CO)2RuH and n-BuLi
in a THF solution and measured its IR spectrum. Five
absorptions were observed at 1907 (s), 1889 (m), 1826
The 31P NMR spectrum of 5 shows a singlet at -42.88
ppm, which is at a higher field by ca. 35 ppm than that
of 1. Similar spectroscopic changes were observed in the
case of the iron complexes. The chemical shift is
consistent with the formation of a phosphorane-migrat-
ed anionic ruthenium complex. The 13C NMR spectrum19
(16) (a) Pannell, K. H.; J ackson, D. J . Am. Chem. Soc. 1976, 98,
4443. (b) Nitay, M.; Rosenblum, M. J . Organomet. Chem. 1977, 136,
C23.
(17) Kawano, Y.; Tobita, H.; Ogino, H. Organometallics 1994, 13,
3849.
(18) Brief IR data have been reported for M′[Cp(CO)2Ru] (M′ ) Na,
K): (a) Gibson, D. H.; Hsu, W.-L.; Ahmed, F. U. J . Organomet. Chem.
1981, 215, 1981. (b) Brookhart, M.; Studabaker, W. B. Organometallics
1987, 6, 1141. (c) Pannell, K. H.; Rozell, J . M.; Tsai, W.-M. Organo-
metallics 1987, 6, 2085.
(19) 13C NMR (δ, THF): 32.20 (s, NCH3), 83.71 (d, J PC ) 18.2 Hz,
PC5H4), 83.98 (d, J PC ) 18.3 Hz, PC5H4), 86.29 (d, J PC ) 17.1 Hz,
PC5H4), 86.41 (d, J PC ) 18.3 Hz, PC5H4), 90.36 (d, J PC ) 253.9 Hz,
PC5H4), 107.57 (d, J PC ) 7.4 Hz, OC6H4N), 108.36 (d, J PC ) 12.2 Hz,
OC6H4N), 118.30 (s, OC6H4N), 119.43 (s, OC6H4N), 136.38 (d, J PC
)
20.8 Hz, OC6H4N), 147.67 (s, OC6H4N), 212.79 (s, CO).

Phosphorane Migration from Ruthenium
Organometallics, Vol. 18, No. 22, 1999 4521
shows five doublets due to the Cp ring. The coupling
constant (253.9 Hz) of the doublet at 90.36 ppm is large
compared with coupling constants of the other four
resonances. This certainly indicates a direct P-C bond.
There are only six resonances assignable to phenyl
rings, showing that two OC6H4NMe groups are mag-
netically equal. The phosphorane phosphorus is reason-
ably expected to have two O atoms in apical positions
and two N atoms and one Cp carbon atom in equatorial
positions. This shows that an apical-equatorial ar-
rangement around the hypervalent phosphorus is re-
tained during its migration from Ru to the Cp ring.
The migration may be initiated by a proton abstrac-
tion on the Cp ring by LDA, followed by migration of
the phosphorane fragment to give 5. The driving force
of this migration can be thought to arise from the more
stable Cp(CO)2Ru- derivative than a species having an
anion on the Cp ring.
Rea ction of [Cp (CO)2Ru {P (OC6H4NMe)(OC6H4-
NMeH)}]BF 4 (6) w ith LDA a n d Th en RX. We previ-
ously reported that the reaction of [Cp(CO)2Ru{P(OPh)3}]-
BF4 with o-C6H4(OH)(NMeH) and n-BuLi in THF gives
a phosphorane complex (1), which then reacts with
PhOH present in the solution to yield the cationic
complex [Cp(CO)2Ru{P(OC6H4NMe)(OC6H4NMeH)}]-
BF4 (6) (eq 2).15 The complexes 1 and 6 may exist in
rings in addition to 1 RuMe resonance, 5 Cp resonances,
and 1 CO resonance. These spectroscopic data indicate
that the product is 7a , shown in Scheme 1 (R ) Me),
where the phosphorane phosphorus has one O atom and
one N atom in apical positions and in equatorial
positions as well. When the solution is warmed to room
temperature, 7a is gradually converted into 2a . An iron
complex corresponding to 7a has not been detected
clearly in the reaction of [Cp(CO)2Fe{P(OC6H4NMe)-
(OC6H4NMeH)}]BF4 with 2 equiv of LDA and then MeI.
Addition of Ph3SnCl, HOCOCF3, and CD3I at -30 °C
to 5 produced from 6 and 2 equiv of LDA gives a similar
31P NMR chemical shift: -30.76 ppm (7c), -29.18 ppm
(7d ), and -28.98 ppm (7a -d 3), respectively. Warming
the solution to room temperature results in the forma-
tion of 2c, 2d , and 2a -d 3, respectively.
In contrast, it is surprising that a reaction of MeI with
5 derived from 1 and LDA does not give 7. Complex 7
is of interest because an amino group occupies an apical
position, though an NR2 group is reported to have
stronger equatophilicity than an OR group. An unusual
trigonal-bipyramidal isomer has been reported by Akiba
and co-workers for an organophosphorane which has an
apical carbon-equatorial oxygen (8 in Chart 2).21 The
31P NMR chemical shift of 8 (-3.5 ppm) is at a lower
field by 15.3 ppm than that of the thermally more stable
isomer 9 (-18.8 ppm). The value and the relative
magnetic-field relation are in fair agreement with those
obtained in our case: the chemical shift of 7 is at a lower
field by 18.4 ppm than that of 2.
To obtain a clue to the formation of 7, we examined
the following reaction. After the formation of 5 from 6,
12-crown-4 was added to the THF solution and then RX
was added at -30 °C. The product in this reaction was
2, and 7 was not detected at all. It was also observed
that addition of 12-crown-4 to a THF solution containing
7 does not apparently affect the isomerization rate to
2. These results indicate that Li+ plays an important
role when 5 reacts with RX. It seems to be related to
the fact that a contact ion pair is a dominant species
for 5. However, how Li+ is involved in this reaction is
not clear at present.
equilibrium, but 6 is readily precipitated out from the
THF solution. The isolated 6 reacts with a base to give
1. Therefore, a phosphorane migration is presumed to
be attained in the reaction of 6 with 2 equiv of LDA
and then RX. As is expected, the migration reaction
takes place to give 2 (eq 3).
During the reaction we encountered interesting find-
ings. In the reaction of 6 with 2 equiv of LDA, formation
of 5 is inferred from the 31P and 13C NMR spectra. Upon
addition of MeI to the solution at -30 °C, a singlet at
-42.88 ppm due to 5 in the 31P NMR spectrum disap-
pears and a new singlet appears at -28.91 ppm. The
13C NMR spectrum20 shows 12 resonances due to phenyl
(20) 13C NMR (δ, THF): -30.11 (s, RuCH3), 88.40 (d, J PC ) 15.9 Hz,
PC5H4), 88.70 (d, J PC ) 17.1 Hz, PC5H4), 95.97 (d, J PC ) 238.1 Hz,
PC5H4), 98.29 (d, J PC ) 20.8 Hz, PC5H4), 100.25 (d, J PC ) 15.9 Hz,
PC5H4), 104.77 (d, J PC ) 8.6 Hz, OC6H4N), 107.69 (d, J PC ) 9.7 Hz,
OC6H4N), 110.21 (d, J PC ) 12.3 Hz, OC6H4N), 110.89 (d, J PC ) 12.2
Hz, OC6H4N), 116.64 (s, OC6H4N), 119.34 (s, OC6H4N), 121.24 (s,
OC6H4N), 122.99 (s, OC6H4N), 134.97 (d, J PC ) 22.0 Hz, OC6H4N),
138.55 (d, J PC ) 17.0 Hz, OC6H4N), 141.79 (s, OC6H4N), 147.39 (s,
OC6H4N), 201.78 (s, CO). Detailed assignments of the NCH3 resonances
were not possible due to interference by resonances of the solvent and
HN(i-Pr)2 existing in the solution.
Con clu sion
We recently reported the first example of hypervalent
phosphorane migration to the Cp ring for iron complexes
(21) Kojima, S.; Kajiyama, K.; Nakamoto, M.; Akiba, K. J . Am.
Chem. Soc. 1996, 118, 12866.

4522 Organometallics, Vol. 18, No. 22, 1999
Nakazawa et al.
OC6H4N), 6.83-6.93 (m, 6H, OC6H4N); 13C NMR (δ, CDCl3)
-31.64 (s, RuCH3), 32.38 (d, J PC ) 2.5 Hz, NCH3), 88.42 (d,
J PC ) 15.9 Hz, PC5H4), 88.82 (d, J PC ) 15.9 Hz, PC5H4), 95.94
(d, J PC ) 251.4 Hz, PC5H4), 99.01 (d, J PC ) 17.1 Hz, PC5H4),
99.87 (d, J PC ) 15.8 Hz, PC5H4), 108.34 (d, J PC ) 7.3 Hz,
OC6H4N), 109.00 (d, J PC ) 12.2 Hz, OC6H4N), 119.53 (s,
OC6H4N), 120.43 (s, OC6H4N), 135.11 (d, J PC ) 22.0 Hz,
OC6H4N), 146.13 (s, OC6H4N), 200.59 (s, CO), 200.72 (s, CO);
31P NMR (δ, THF) -47.27 (s).
Ch a r t 2
P r ep a r a t ion of {C5H 4P (OC6H 4NMe)2}(CO)2R u CH2P h
(2b). Treatment of 6 (252 mg, 0.43 mmol) with LDA (1.73 mL,
0.86 mmol) followed by PhCH2Cl (0.060 mL, 0.52 mmol) in a
manner similar to that for 2a gave a white powder of 2b (130
mg, 0.22 mmol, 51%). Anal. Calcd for C28H25N2O4PRu: C,
57.43; H, 4.30; N, 4.78. Found: C, 57.13; H, 4.37; N, 4.67.
Data: IR (cm-1, THF) νCO 2019, 1961; 1H NMR (δ, CDCl3) 2.84
(d, J HH ) 8.6 Hz, 1H, RuCH2), 2.92 (d, J HH ) 8.9 Hz, 1H,
RuCH2), 3.23 (d, J PH ) 10.2 Hz, 6H, NCH3), 4.85-4.96 (m, 2H,
PC5H4), 5.60-5.63 (m, 1H, PC5H4), 5.68-5.71 (m, 1H, PC5H4),
6.80-7.11 (m, 13H, OC6H4N, CH2C6H5); 13C NMR (δ, CDCl3)
0.29 (s, RuCH2), 32.40 (d, J PC ) 2.4 Hz, NCH3), 89.96 (d, J PC
) 14.6 Hz, PC5H4), 91.42 (d, J PC ) 15.9 Hz, PC5H4), 95.61 (d,
J PC ) 250.2 Hz, PC5H4), 98.81 (d, J PC ) 15.8 Hz, PC5H4), 101.09
(d, J PC ) 15.9 Hz, PC5H4), 108.41 (d, J PC ) 7.3 Hz, OC6H4N),
109.12 (d, J PC ) 11.0 Hz, OC6H4N), 119.64 (s, OC6H4N), 120.54
(s, OC6H4N), 122.86 (s, CH2C6H5), 127.33 (s, CH2C6H5), 127.96
(s, CH2C6H5), 135.01 (d, J PC ) 22.0 Hz, OC6H4N), 146.11 (s,
OC6H4N), 153.51 (s, CH2C6H5), 200.11 (s, CO), 200.65 (s, CO);
31P NMR (δ, THF) -47.46 (s).
Cp(CO)2Fe{P(OC6H4Z)2} (Z ) NR, O). The reaction is
proposed to be initiated by a proton abstraction on the
Cp ring by a Lewis base, followed by migration of the
phosphorane fragment to the Cp ring via a metalated
hypervalent hexacoordinated phosphorus species as an
intermediate. It is generally accepted that a bond
between a transition metal and a main-group element
becomes strong on going down in the periodic table for
transition metals in the same group. In this paper we
examined a phosphorane migration for ruthenium com-
plexes, Cp(CO)2Ru{P(OC6H4Z)2}, with the expectation
of obtaining or detecting the proposed intermediate. The
results showed the second hypervalent fragment migra-
tion, but the reaction did not enable us to detect an
expected intermediate. However, we encountered for-
mation of the unexpected phosphorane migration com-
plex {η5-C5H4P(OC6H4NMe)2}(CO)2RuR, which contains
one O atom and one N atom in apical positions and in
equatorial positions as well.
P r epar ation of {C5H4P (OC6H4NMe)2}(CO)2Ru Sn P h 3 (2c).
Treatment of 6 (108 mg, 0.19 mmol) with LDA (0.74 mL, 0.37
mmol) followed by Ph3SnCl (73 mg, 0.19 mmol) in a manner
similar to that for 2a gave a white powder of 2c (110 mg, 0.13
mmol, 70%). Anal. Calcd for C39H33N2O4PRuSn: C, 55.47; H,
3.94; N, 3.32. Found: C, 55.31; H, 4.03; N, 3.19. Data: IR
Exp er im en ta l Section
1
(cm-1, THF) νCO 2016, 1962; H NMR (δ, CDCl3) 3.15 (d, J PH
Gen er a l Rem a r k s. All reactions were carried out under
an atmosphere of dry nitrogen by using standard Schlenk tube
techniques. All solvents were purified by distillation: THF and
benzene were distilled from sodium/benzophenone, hexane and
pentane were distilled from sodium metal, and CH2Cl2 was
distilled from P2O5. Those were stored under an N2 atmo-
sphere. Other reagents employed in this research were used
as received.
IR spectra were recorded on Shimadzu FTIR-4000 and
FTIR-8100A spectrometers. 1H, 13C, and 31P NMR spectra were
measured on J EOL EX-270, EX-400, and LA-300 spectrom-
eters. 1H NMR and 13C NMR data were referenced to Si(CH3)4
as an internal standard. 31P NMR data were referred to 85%
H3PO4 as an external standard. Elemental analyses were
performed on a Perkin-Elmer 2400CHN elemental analyzer.
Ruthenium complexes (1, 3, and 6) were prepared in
accordance with the reported procedures.15 Ruthenium com-
plexes (2) can be prepared from 1 and also from 6. Procedures
for preparation of 2 from 6 were described below.
) 10.3 Hz, 6H, NCH3), 4.73-4.77 (m, 1H, PC5H4), 4.82-4.86
(m, 1H, PC5H4), 5.43-5.46 (m, 1H, PC5H4), 5.59-5.61 (m, 1H,
PC5H4), 6.59 (d, J HH ) 8.8 Hz, 2H, OC6H4N), 6.71-6.82 (m,
6H, OC6H4N), 7.18-7.22 (m, 9H, SnC6H5), 7.36-7.39 (m, 6H,
SnC6H5); 13C NMR (δ, CDCl3) 32.34 (d, J PC ) 2.5 Hz, NCH3),
86.52 (d, J PC ) 14.9 Hz, PC5H4), 87.36 (d, J PC ) 14.9 Hz,
PC5H4), 92.11 (d, J PC ) 15.3 Hz, PC5H4), 93.86 (d, J PC ) 15.3
Hz, PC5H4), 98.37 (d, J PC ) 246.8 Hz, PC5H4), 104.48 (d, J PC
) 7.5 Hz, OC6H4N), 109.29 (d, J PC ) 12.4 Hz, OC6H4N), 119.75
(s, OC6H4N), 120.65 (s, OC6H4N), 128.02 (s, with Sn satellites,
J SnC ) 9.9 Hz, SnC6H5), 128.13 (s, with Sn satellites, J SnC
)
45.4 Hz, SnC6H5), 134.87 (d, J PC ) 21.8 Hz, OC6H4N), 136.63
(s, with Sn satellites, J SnC ) 39.2 Hz, SnC6H5), 143.65 (s,
SnC6H5), 146.19 (s, OC6H4N), 198.50 (s, CO), 200.14 (s, CO);
31P NMR (δ, THF) -49.25 (s).
P r ep a r a tion of {C5H4P (OC6H4NMe)2}(CO)2Ru H (2d ).
Treatment of 6 (154 mg, 0.26 mmol) with LDA (1.1 mL, 0.55
mmol) followed by CF3COOH (0.020 mL, 0.26 mmol) in a
manner similar to that for 2a gave a pale yellow powder of 2d
(55 mg, 0.11 mmol, 42%). Anal. Calcd for C21H19N2O4PRu: C,
50.91; H, 3.87; N, 5.65. Found: C, 51.21; H, 3.94; N, 5.65.
Data: IR (cm-1, THF) νCO 2029, 1969; 1H NMR (δ, C6D6)
-10.80 (s, 1H, RuH), 2.87 (d, J PH ) 10.3 Hz, 6H, NCH3), 4.47
(m, 2H, PC5H4), 5.39 (m, 1H, PC5H4), 5.52 (m, 1H, PC5H4),
6.36-7.28 (m, 8H, OC6H4N); 13C NMR (δ, C6D6) 32.10 (s,
NCH3), 86.37 (d, J PC ) 14.6 Hz, PC5H4), 86.86 (d, J PC ) 15.9
P r ep a r a tion of {C5H4P (OC6H4NMe)2}(CO)2Ru CH3 (2a ).
A white suspension of 6 (219 mg, 0.38 mmol) in THF (2 mL)
was treated with LDA (1.5 mL, 0.75 mmol) at -78 °C. After it
had been stirred at -78 °C for 15 min, the reaction mixture
was treated with MeI (0.030 mL, 0.48 mmol), warmed to room
temperature, and then stirred for 2 h to complete the reaction.
The solvent was removed under reduced pressure, and the
residue was extracted with a small amount of benzene. The
extract was loaded on a silica gel column and eluted with a
mixture of hexane and benzene (2/3). The colorless band eluted
first was collected, and the solvents were removed in vacuo to
give 2a as a white powder (88 mg, 0.17 mmol, 46%). Anal.
Calcd for C22H21N2O4PRu: C, 51.87; H, 4.15; N, 5.50. Found:
Hz, PC5H4), 94.49 (d, J PC ) 17.1 Hz, PC5H4), 95.34 (d, J PC
)
15.9 Hz, PC5H4), 95.41 (d, J PC ) 247.8 Hz, PC5H4), 108.55 (d,
J PC ) 5.9 Hz, OC6H4N), 109.69 (d, J PC ) 12.2 Hz, OC6H4N),
120.04 (s, OC6H4N), 120.97 (s, OC6H4N), 135.19 (d, J PC ) 21.9
Hz, OC6H4N), 146.76 (s, OC6H4N), 199.93 (s, CO), 200.16 (s,
CO); 31P NMR (δ, C6D6) -47.82 (s).
C, 52.08; H, 4.23; N, 5.51. Data: IR (cm-1, THF) νCO 2020,
1
1959; H NMR (δ, CDCl3) 0.27 (s, 3H, RuCH3), 3.23 (d, J PH
)
P r ep a r a tion of {C5H4P (OC6H4NMe)2}(CO)2Ru CD3 (2a -
d 3). Treatment of 6 (190 mg, 0.33 mmol) with LDA (1.3 mL,
0.65 mmol) followed by CD3I (0.038 mL, 0.60 mmol) in a
10.2 Hz, 6H, NCH3), 5.16-5.20 (m, 2H, PC5H4), 5.67-5.70 (m,
1H, PC5H4), 5.76-5.79 (m, 1H, PC5H4), 6.67-6.70 (m, 2H,

Phosphorane Migration from Ruthenium
Organometallics, Vol. 18, No. 22, 1999 4523
manner similar to that for 2a gave a white powder of 2a -d 3
(92 mg, 0.18 mmol, 55%). Anal. Calcd for C22H18D3N2O4PRu:
C, 51.56; H, 3.56; D, 1.15; N, 5.47. Found: C, 51.60; H, 3.55;
D, 1.15; N, 5.56. Data: IR (cm-1, THF) νCO 2021, 1962; 1H NMR
(δ, CDCl3) 3.23 (d, J PH ) 10.2 Hz, 6H, NCH3), 5.17-5.21 (m,
2H, PC5H4), 5.67-5.70 (m, 1H, PC5H4), 5.77-5.79 (m, 1H,
PC5H4), 6.67-6.70 (m, 2H, OC6H4N), 6.81-6.94 (m, 6H,
OC6H4N); 13C NMR (δ, CDCl3) 32.37 (s, NCH3), 88.38 (d, J PC
) 14.6 Hz, PC5H4), 88.75 (d, J PC ) 14.6 Hz, PC5H4), 95.86 (d,
J PC ) 250.2 Hz, PC5H4), 98.99 (d, J PC ) 17.1 Hz, PC5H4), 99.82
(d, J PC ) 14.7 Hz, PC5H4), 108.30 (d, J PC ) 7.3 Hz, OC6H4N),
108.99 (d, J PC ) 12.2 Hz, OC6H4N), 119.50 (s, OC6H4N), 120.40
(s, OC6H4N), 135.08 (d, J PC ) 22.0 Hz, OC6H4N), 146.09 (s,
OC6H4N), 200.61 (s, CO), 200.74 (s, CO), the CD3 carbon could
not be identified; 31P NMR (δ, THF) -47.47 (s).
constants and an orientation matrix for data collection,
obtained from a least-squares refinement using the setting
angles of 32 carefully centered reflections in the range 29° <
2θ < 36°, corresponded to a monoclinic cell with dimensions
of a ) 10.753(3) Å, b ) 29.180(7) Å, c ) 8.015(3) Å, â ) 94.32-
(3)°, Z ) 4, and V ) 2507.9(1) Å3. P21/c was selected as a space
group which led to successful refinement. The data were
collected at a temperature of 20 ( 1 °C using the ω scan
technique. The intensities of three representative reflections
were measured after 300 reflections. No decay correction was
applied.
The structure was solved by direct methods with the SIR-
92 program system.22 The positions of all hydrogen atoms were
calculated by assuming idealized geometries. Absorption and
extinction corrections were then applied,23,24 and several cycles
of a full-matrix least-squares refinement with anisotropic
temperature factors for non-hydrogen atoms led to final R and
Rw values of 0.034 and 0.037, respectively. All calculations
were performed using Crystan-GM.25
P r ep a r a tion of {C5H4P (OC6H4O)2}(CO)2Ru CH3 (4). 3
(125 mg, 0.26 mmol) was dissolved in THF (4.0 mL), and LDA
(0.53 mL, 0.27 mmol) was added to the solution at -78 °C.
The mixture was stirred for 15 min. The solution was then
treated with MeI (0.032 mL, 0.53 mmol) and warmed to room
temperature. The solvent was removed under reduced pres-
sure, and the residue was extracted with ether. The extract
was dried in vacuo, and the resulting oily residue was
extracted with pentane. The pentane extract was filtered, and
the solvent was removed under reduced pressure to give a
white powder of 4 (101 mg, 0.21 mmol, 79%). The complex was
so hygroscopic that the correct elemental analysis data could
not be obtained, though satisfactory spectroscopic data were
Ack n ow led gm en t. This work was supported by a
Grant-in-Aid for Science Research (Grant No. 10440195)
and a Grant-in-Aid on Priority Area of Interelement
Chemistry (Grant No. 11120235) from the Ministry of
Education, Science, Sports and Culture of J apan.
Su p p or tin g In for m a tion Ava ila ble: Tables giving posi-
tional and thermal parameters and bond distances and angles
for 2b (6 pages). Ordering information is given on any current
masthead page.
1
obtained. Data: IR (cm-1, THF) νCO 2016, 1959; H NMR (δ,
CDCl3) 0.32 (s, 3H, RuCH3), 5.27-5.31 (m, 2H, PC5H4), 5.85-
5.87 (m, 2H, PC5H4), 6.93-7.08 (m, 8H, OC6H4O); 13C NMR
(δ, CDCl3) -30.82 (s, RuCH3), 84.73 (d, J PC ) 249.2 Hz, PC5H4),
90.63 (d, J PC ) 16.2 Hz, PC5H4), 99.76 (d, J PC ) 16.8 Hz,
PC5H4), 110.98 (d, J PC ) 14.3 Hz, OC6H4O), 122.33 (s,
OC6H4O), 143.72 (d, J PC ) 4.4 Hz, OC6H4O), 198.91 (s, CO);
31P NMR (δ, THF) -14.41 (s).
X-r a y Str u ctu r e Deter m in a tion for 2b. A single crystal
of 2b grown from pentane in a refrigerator was mounted on a
Mac Science MXCκ diffractometer and irradiated with graphite-
monochromated Mo KR radiation (λ ) 0.710 73 Å). Cell
OM9904145
(22) Altomare, A.; Cascarano, G.; Giacovazzo, C.; Gurgliardi, A.;
Burla, M. C.; Polidori, G.; Camalli, M. SIR-92; University of Bari: Bari,
Italy, 1992.
(23) Katayama, C. Acta Crystallogr., Sect. A 1986, A42, 19.
(24) Coppens, P.; Hamilton, W. C. Acta Crystallogr., Sect. A 1970,
A26, 71.
(25) Crystan-GM: A Computer Program for the Solution and
Refinement of Crystal Structures from X-ray Diffraction Data; Mac-
Science Co., Ltd., Yokohama, J apan, 1995.