C-H vs. N-H bond activation in aminophosphane ligands: Reaction of [Cp*Ru(MeCN)2(PR12NHR2)] + (R1 = Ph, iPr; R2 = Ph, C6F 5) with alkynes

Article abstract of DOI:10.1002/ejic.200500034

The reaction of the complexes [Cp*Ru(MeCN)₂(PR ¹₂NHR²)]⁺ (R¹ = R ² = Ph 1; R¹ = iPr, R² = C₆F ₅ 2; R¹ = iPr, R²

Full text of DOI:10.1002/ejic.200500034

FULL PAPER
C–H vs. N–H Bond Activation in Aminophosphane Ligands: Reaction of
[Cp*Ru(MeCN)2(PR1 NHR2)]+ (R1 = Ph, iPr; R2 = Ph, C6F5) with Alkynes
2
Manuel Jiménez-Tenorio,[a] M. Carmen Puerta,[a] and Pedro Valerga*[a]
Dedicated to the memory of Prof. Francisco González García (Universidad de Sevilla)[‡]
Keywords: Alkyne ligands / C–H activation / Half-sandwich complexes / Phosphane ligands / Ruthenium
The reaction of the complexes [Cp*Ru(MeCN)2(PR12NHR2)]+
bond activation at the ortho-position of the phenyl ring of
the phenylamino moiety and coupling to the alkyne fragment
takes place. This results in the formation of the novel π-al-
(R1 = R2 = Ph 1; R1 = iPr, R2 = C6F5 2; R1 = iPr, R2 = Ph 3) with
1-alkynes HCϵCR (R
HCϵCCH2XCH2CϵCH (X = O, CH2, CH2CH2) yields dif-
ferent products depending on the nature of the aminophos- NHPiPr2-κ1P}]+ (R = nBu 4, SiMe3 5), formally derived from
= H, nBu, SiMe3) or diynes
kene
complexes
[Cp*Ru(MeCN){η2-RCH=CH(C6H4)-
phane ligand. In some cases, alkyne coupling involving mi-
gration of the phosphane and N–H activation occurs, yielding
amidobutadiene complexes of the type [Cp*Ru{η4-C4H3(R)2-
PR12NR2-κ1N}]+ or [Cp*Ru{η4-C4H3(CH2XCH2)PR12NR2-
the insertion of the alkyne into the ortho-C–H bond of the
phenyl ring. The derivative
[Cp*Ru(MeCN){η2-
nBuCH=CH(C6H4)NHPiPr2-κ1P}][BPh4] has been structurally
characterized by X-ray crystallography. These compounds
are related to the also structurally characterized olefin com-
plex [Cp*Ru(MeCN)(η2-MeOOCCH=CH2)(PPh2NHPh)][PF6]
(6), generated by reaction of 1 with methyl acrylate.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2005)
κ1N}]+.
PPh2NPh-κ1N}][PF6]
The
complexes
(1a)
[Cp*Ru{η4-C4H3(CH2OCH2)-
and
[Cp*Ru{η4-C4H3(CH2-
OCH2)PiPr2NC6F5-κ1N}][PF6] (2a) have been structurally
characterized by X-ray crystallography. In other cases, for ex-
ample the reaction of 3 with HCϵCR (R = nBu, SiMe3), C–H
Introduction
Complexes of the type [(C5R5)Ru(MeCN)2(L)]+ (R = H,
Me; L = CO, PR3, AsPh3, SbPh3) are regarded as synthons
for the corresponding cationic 14-electron fragments
[(C5R5)Ru(L)]+ due to the substitutionally labile character
of the acetonitrile ligands.[1] The reactivity of these systems
towards alkynes has been thoroughly studied both from the
experimental and theoretical points of view.[1–5] The deriva-
tives [(C5R5)Ru(MeCN)2(L)]+ react with alkynes to yield
bis(π-alkyne) adducts which readily undergo oxidative al-
kyne coupling of the two alkyne ligands to form cationic
ruthenacyclopentatriene complexes.
Ruthenacyclopentatriene complexes are key intermedi-
ates in the overall process, and the final products of the
reaction are determined by the nature of L, the use of Cp
or Cp* as co-ligands, and the nature of the substituents
present in the alkyne.[1] When L is PR3, migration of the
phosphane from Ru to C occurs in most cases, generating
allyl carbene species.[2–4] These species behave as masked
coordinatively unsaturated complexes that are capable of
activating C–H bonds. In cyclopentadienyl complexes con-
taining tertiary phosphane ligands the C–H activation pro-
cess takes place at one of the aryl or alkyl substituents of
the phosphane.[4,6]
[a] Departamento de Ciencia de Materiales e Ingeniería Metalúrg-
ica y Química Inorgánica, Facultad de Ciencias, Universidad
de Cádiz,
Apartado 40, 11510 Puerto Real, Cádiz, Spain
Fax: +34-956-016288
E-mail: pedro.valerga@uca.es
At variance with this, in pentamethylcyclopentadienyl
derivatives the C–H activation occurs at one of the methyl
[‡] For his contribution to the development of Inorganic Chemistry
in Spain.
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DOI: 10.1002/ejic.200500034
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M. Jiménez-Tenorio, M. C. Puerta, P. Valerga
FULL PAPER
substituents of the Cp* ring to yield η6-fulvene com- substituent on the alkyne. The detailed results are discussed
plexes.[6]
below.
Results and Discussion
The complexes [Cp*Ru(MeCN)2(PR1 NHR2)]+ (R1 = R2
2
= Ph 1; R1 = iPr, R2 = C6F5 2; R1 = iPr, R2 = Ph 3) were
prepared by treatment of [Cp*Ru(MeCN)3][PF6] with a
stoichiometric amount of the corresponding aminophos-
phane in dichloromethane; they were isolated either as their
–
–
PF6 (1 and 2) or BPh4 (3) salts.
Treatment of 1, 2, or 3 with either propargyl ether or 1,6-
heptadiyne led to the isolation after purification, in moder-
ate yields, of the corresponding amidobutadiene complexes
In all cases, the result of the phosphane migration to the
organic fragment and the subsequent C–H activation pro-
cess is the formation of η4-butadiene species. Very recently,
Kirchner and co-workers have reported the activation of
alkynes by the aminophosphane complex [CpRu(MeCN)
2(PPh2NHPh)]+, which results in the formation of η4-ami-
dobutadiene complexes.[7] In this case phosphane migration
also occurs, and is followed by an N–H bond activation
process in the amino group rather than C–H bond acti-
vation.
[Cp*Ru(η4-C4H3(X)PR1 NR2-κ1N)]+ [R1 = R2 = Ph, X =
2
CH2OCH2 1a, (CH2)3 1b; R1 = iPr, R2 = C6F5, X =
CH2OCH2 2a, (CH2)3 2b; R1 = iPr, R2 = Ph, X =
CH2OCH2 3a, (CH2)3 3b]. In analogous fashion, treatment
of 1 and 3 with 1,7-octadiyne also led to the corresponding
amidobutadiene complexes 1c and 3c, respectively, whereas
the reaction of 2 with 1,7-octadiyne yielded a mixture from
which no pure compound could be isolated. The reaction
of 1 with HCϵCR (R = H, nBu) also afforded the corre-
sponding amidobutadiene complexes [Cp*Ru{η4-C4H3(R)2-
PPh2NPh-κ1N}][PF6] (R = H 1d, nBu 1e). All these com-
1
pounds were characterized by NMR spectroscopy. The H
and 13C{1H}NMR spectra are consistent with those re-
ported for the related cyclopentadienyl amidobutadiene
complexes.[7] One of the most distinctive spectral features
of these complexes is the resonance for H1 and C1 in their
1
respective H and 13C{1H} NMR spectra. Given the fact
that C1 is the carbon atom to which the phosphorus atom
Given the previously observed behavior differences be- is bonded, its 13C{1H} resonance appears as a doublet with
1
tween [CpRu(MeCN)2(PR3)]+ and the homologous a rather large JC,P coupling constant in the range 100–
[Cp*Ru(MeCN)2(PR3)]+ complexes with respect to the C– 115 Hz. The hydrogen atom attached to C1 appears as a
2
H activation processes,[6] we have addressed the question of doublet with a value for the JH,P coupling constant of
whether N–H or C–H activation should occur in the case around 16 Hz. C2 is a quaternary carbon atom in all cases
of Cp* complexes containing aminophosphane ligands. except for compound 1d. In this case, the hydrogen atom
3
Hence, we have studied the interaction of 1-alkynes with attached to C2 displays a large JH,P coupling constant of
the cationic complexes [Cp*Ru(MeCN)2(PR1 NHR2)]+. We 28 Hz with the phosphorus atom in the trans-position. The
2
have found that either N–H or C–H activation may take 31P{1H} NMR spectra consist of one singlet in all cases,
place depending upon the aminophosphane ligand and the which is shifted to high-field by 20 to 35 ppm with respect
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C–H vs. N–H Bond Activation in Aminophosphane Ligands
FULL PAPER
to the position of the 31P{1H} NMR resonance for the cor-
responding bis(acetonitrile) parent compound 1, 2, or 3
respectively. This is fully consistent with the fact that mi-
gration of phosphorus from ruthenium to carbon has oc-
curred.
The X-ray crystal structures of 1a and 2a were deter-
mined. ORTEP views of the cations [Cp*Ru{η4-
C4H3(CH2OCH2)PPh2NPh-κ1N}]+
and
[Cp*Ru{η4-
C4H3(CH2OCH2)PiPr2NC6F5-κ1N}]+ are shown in Fig-
ures 1 and 2, respectively, together with a listing of selected
bond lengths and angles.
Figure 2. ORTEP drawing (50% thermal ellipsoids) of the cation
[Cp*Ru{η4-C4H3(CH2OCH2)-PiPr2NC6F5-κ1N}]+ in complex 2a.
Hydrogen atoms have been omitted. Selected bond lengths [Å] and
angles [°] with estimated standard deviations in parentheses: Ru1–
C1 2.167(4), Ru1–C5 2.189(3), Ru1–C2 2.198(4), Ru1–C4 2.216(4),
Ru1–C3 2.242(4), Ru1–N1 2.242(3), Ru1–C16 2.208(4), Ru1–C15
2.227(4), Ru1–C12 2.219(4), Ru1–C11 2.208(4), P1–C11 1.771(4),
C15–C16 1.392(5), C12–C15 1.425(5), C11–C12 1.410(5), N1–P1
1.605(3); Ru1–N1–P1 97.0(1), C11–Ru1–N1 70.2(1), N1–P1–C11
98.35(16), C16–C15–C12 128.1(3), C15–C12–C11 129.5(3).
final amidobutadiene products.[7] However, we have found
that in certain cases a different reaction pathway that leads
to products other than amidobutadiene complexes is feas-
ible.
The reaction of 3 with 1-hexyne or HCϵCSiMe3 in
dichloroethane yielded yellow materials that show one sing-
let in their respective 31P{1H} NMR spectra slightly above
δ = 100 ppm. This indicates that migration of the amino-
phosphane ligands does not take place in these two cases,
at variance with all the other reactions studied in this work.
Figure 1. ORTEP drawing (50% thermal ellipsoids) of the cation
[Cp*Ru{η4-C4H3(CH2OCH2)-PPh2NPh-κ1N}]+ in complex 1a.
Hydrogen atoms have been omitted. Selected bond lengths [Å] and
angles [°] with estimated standard deviations in parentheses: Ru1–
C2 2.182(2), Ru1–C3 2.188(2), Ru1–C4 2.210(2), Ru1–C1 2.218(2),
Ru1–C5 2.245(2), Ru1–N1 2.164(1), Ru1–C11 2.244(2), Ru1–C12
2.216(2), Ru1–C13 2.223 (2), Ru1–C16 2.217(2), P1–C16 1.766(2),
C11–C12 1.401(3), C12–C13 1.420(3), C13–C16 1.413(3), N1–P1
1.599(2); Ru1–N1–P1 96.89(7), N1–Ru1–C16 72.30(7), N1–P1–C16
100.23(8), C11–C12–C13 128.1(2), C12–C13–C16 129.5(2).
1
Furthermore, the observed patterns in the H and 13C{1H}
NMR spectra of these substances are remarkably different
from the expected ones for amidobutadiene complexes. The
NMR spectra are consistent with the presence of coordi-
The structures of the complex cations are very similar to nated acetonitrile and NH groups. A series of multiplet res-
1
those of the related cyclopentadienyl amidobutadiene com- onances in the H NMR spectra in the range δ = 2.6 to
plexes [CpRu{η4-C4H3(CH2CH2CH2)PPh2NPh-κ1N}]+ and 3.9 ppm are correlated to two tertiary carbon resonances
[CpRu{η4-C4H3(nBu)2PPh2NPh-κ1N}]+.[7] The dimensions in their respective 13C{1H} NMR spectra, as inferred from
of the butadiene fragment are consistent with the delocal- DEPT and gHSQC NMR experiments, thereby suggesting
ization of the double bonds, matching the values reported the presence of an η2-CH=CH group in the complexes. The
for the cyclopentadienyl complexes. The Ru1–N1 separa- X-ray structure analysis performed on crystals resulting
tion of 2.242(3) Å in 2a is significantly longer than the cor- from the reaction of 3 with 1-hexyne revealed the formation
responding Ru–N bond lengths observed in 1a and in the of the complex [Cp*Ru(MeCN){η2-nBuCH=CH(C6H4)-
cyclopentadienyl derivatives. This difference reflects the ef- NHPiPr2-κ1P}][BPh4] (4). The product resulting from the
fect of the electron-attracting C6F5 group attached to the reaction of 3 with HCϵCSiMe3 was then identified
nitrogen atom in 2a. On the other hand, all P–N and P–C as[Cp*Ru(MeCN){η2-Me3SiCH=CH(C6H4)NHPiPr2-κ1P}]-
separations have similar values, and are unexceptional.
[BPh4] (5).
The reactions of the pentamethylcyclopentadienyl bis-
An ORTEP view of the cation [Cp*Ru(MeCN){η2-
(acetonitrile) complexes 1–3 with diynes or 1-alkynes exam- nBuCH=CH(C6H4)NHPiPr2-κ1P}]+ is shown in Figure 3,
ined so far seem to follow a pathway identical to that of the together with a listing of selected bond lengths and angles.
cyclopentadienyl derivative [CpRu(MeCN)2(PPh2NHPh)]+, The ruthenium atom in the complex cation is bonded to
with phosphane migration, formation of an allyl carbene one acetonitrile ligand, to the phosphorus atom of the ami-
species, and an N–H bond activation process leading to the nophosphane, and to an olefin ligand η2-nBuCH=CH re-
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M. Jiménez-Tenorio, M. C. Puerta, P. Valerga
FULL PAPER
For these processes we propose the reaction sequence
shown in Scheme 1. After substitution of the first acetoni-
trile ligand by one alkyne molecule, the second acetonitrile
molecule dissociates from the metal to generate a coordina-
tively unsaturated complex. If the addition of the second
alkyne ligand is fast, then the resulting 18-electron bis(al-
kyne) complex undergoes oxidative alkyne coupling to yield
a ruthenacyclopentatriene complex, and the course of the
reaction would be as described previously.[1,7] However, in
certain cases involving systems containing the strong elec-
tron-releasing aminophosphane iPr2PNHPh, the metal cen-
ter in the 16-electron intermediate is electron-rich enough
to activate one C–H bond in the ortho-position of the
phenyl ring to yield an orthometalated hydrido complex as
a result of the oxidative addition reaction. This RuIV species
is most likely in dynamic equilibrium with the 16-electron
complex. Insertion of the alkyne into the ruthenium–hy-
dride bond yields an alkenyl complex, which, upon addition
of acetonitrile and reductive coupling of the alkenyl and
phenyl fragments, leads to the final reaction product 4 or
5. In the reaction of 3 with potentially chelating diynes the
addition of the second alkyne to the 16-electron intermedi-
ate seems to be faster than the oxidative addition of the
phenyl C–H and the subsequent alkyne insertion, and hence
the amidobutadiene complexes 3a–c are obtained.
sulting formally from the insertion of the triple bond of a
1-hexyne molecule into one of the ortho-CH bonds of the
NHPh group of the aminophosphane. The stereochemistry
of the olefin ligand is trans. The C11–C12 separation of
1.42(1) Å, and the Ru1–C11 and Ru1–C12 bond lengths of
2.233(8) Å and 2.198(8) Å, respectively, compare well with
the values found in other half-sandwich ruthenium η2-al-
kene complexes, such as [Cp*Ru(η2-CH2=CH2)(dippe)]+
[C–C: 1.43(2) Å; Ru–C: 2.24(1) Å and 2.25(1) Å; dippe =
1,2-bis(diisopropylphosphanyl)ethane][8] or [Cp*Ru(η2-
CH2=CH2)(CO)(PMeiPr2)]+ [C–C: 1.416(13) Å; Ru–C:
2.197(8) Å and 2.204(7) Å].[9]
The fact that reaction products similar to 4 or 5 are not
observed in the course of the reaction of 1 or 2 with alkynes
might be due to the following reasons: 1) in 1, the
PPh2NHPh ligand is less basic than iPr2PNHPh, and hence
the corresponding 16-electron intermediate complex is
probably not electron-rich enough to cleave ortho-C–H
bonds prior to the entry of the second alkyne molecule, and
2) in the case of compound 2, a final product analogous to
4 or 5 would involve C–F bond activation, a process which
has a higher activation energy barrier than C–H bond acti-
vation.[10]
We must remark here that the proposed reaction se-
quence shown in Scheme 1, although reasonable, is only
tentative. However, we must also point out the fact that
spectroscopic evidence for the involvement of hydrido com-
plexes in the formation of 4 has been obtained. In some
instances, compound 4 was isolated accompanied by small
amounts of other material which exhibits one hydride
doublet resonance at δ = –10.89 ppm, with a 2JH,P coupling
Figure 3. ORTEP drawing (50% thermal ellipsoids) of the cation
[Cp*Ru(MeCN){η2-nBuCH=CH(C6H4)NHPiPr2-κ1P}]+ in com-
plex 4. Hydrogen atoms have been omitted. Selected bond lengths
[Å] and angles [°] with estimated standard deviations in parenthe-
ses: Ru1–C1 2.227(8), Ru1–C2 2.254(8), Ru1–C3 2.247(9), Ru1–C4
2.227(8), Ru1–C5 2.208(9), Ru1–N2 2.032(7), Ru1–C11 2.233(8),
Ru1–C12 2.198(8), Ru1–P1 2.327(2), P1–N1 1.688(7), C11–C12
1.42(1); Ru1–P1–N1 108.1(3), Ru1–N2–C29 169.1(7), C11–C12–
C13 123.5(8), C12–C11–C17 122.7(8), C13–C12–C11–C17
139.2(9).
1
constant of 43.9 Hz, in the H NMR spectrum (Figure 4).
2
The relatively large value of the JH,P coupling constant
suggests a transoid disposition of the hydride and phos-
phane ligands. One singlet resonance at δ = 135.8 ppm in
the 31P{1H} NMR spectrum was attributed to this hydrido
Complexes 4 and 5, which incorporate only one alkyne complex.
molecule, are isolated even when compound 3 is allowed to
The reaction of 3 with an excess of 1-hexyne in [D2]tetra-
react with an excess of the corresponding 1-alkyne. This chloroethane was monitored between 0 and 60 °C. Several
fact indicates that the ruthenacyclopentatriene complex, intermediate species giving rise to singlets in the 31P{1H}
which is a key intermediate in the process of formation of NMR spectra were detected. One of these intermediate spe-
allyl carbene species, is not generated in the course of the cies is responsible for the doublet hydride resonance ob-
reaction of 3 with 1-hexyne or HCϵCSiMe3, and therefore served in the 1H NMR spectrum. Although the isolation of
an alternative reaction pathway leading to 4 and 5 is feas- any of these intermediate species was not possible, there is
ible.
little doubt about the involvement of hydride species in the
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C–H vs. N–H Bond Activation in Aminophosphane Ligands
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Scheme 1. Proposed reaction sequence for the formation of 4 or 5 by C–H activation.
Figure 4. 1H NMR spectrum (400 MHz) of crude compound 4 in [D6]acetone, showing the presence of minor amounts of a hydrido
complex.
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M. Jiménez-Tenorio, M. C. Puerta, P. Valerga
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process. Orthometalation processes at coordinatively unsat- any atom from the aminophosphane ligand are around 3 Å
urated metal centers leading to hydrido-phenyl species have or longer, which indicates no significant interaction between
been well documented in the literature.[11–14]
the aminophosphane and the olefin in this complex.
We also carried out reactions of 1, 2, and 3 with several
We also studied the reactions of 5 with alkynes in order
olefins. The only characterized product from these reactions to check the possibility of alkene–alkyne coupling. How-
was the η2-alkene complex [Cp*Ru(MeOOCCH=CH2)- ever, this does not occur. The reaction of 5 with propargyl
(MeCN)(PPh2NHPh)][PF6] (6), which was obtained from ether yielded red-orange crystals of the amidobutadiene
the reaction of 1 with methyl acrylate. The substitution of complex 1a. Likewise, the reaction with acetylene afforded
only one acetonitrile ligand in 1 was accomplished irrespec- the corresponding amidobutadiene derivative 1d. Hence,
tive of the metal to methyl acrylate ratio used in the reac- the methyl acrylate and acetonitrile ligands behave as good
tion. The protons of the η2-CH=CH2 group of the methyl leaving groups in these reactions, and are readily substituted
acrylate ligand appear as multiplets at δ = 2.61, 3.45, and by alkynes to give bis(alkyne) complexes, which follow the
3.52 ppm in the 1H NMR spectrum, whereas the resonances previously discussed reaction pathway to form amidobuta-
for the carbon atoms appear as doublets at δ = 46.5 and diene complexes by N–H activation.
52.2 ppm, with JC,P coupling constant values of 5.4 Hz and
17 Hz, respectively.
The crystal structure of 6 was determined. An ORTEP
view of the cation [Cp*Ru(η2-MeOOCCH=CH2)-
(MeCN)(PPh2NHPh)]+ is shown in Figure 5, together with
a listing of selected bond lengths and angles. The coordina-
tion sphere around ruthenium is very similar to that of
complex 4, consisting of one Cp*, one acetonitrile ligand,
one aminophosphane ligand, and the η2-methyl acrylate li-
gand. The dimensions of the alkene ligand compare well
with the values found for 4, and for other compounds re-
ported in the literature.[8,9] Only one diastereoisomer is
present in the crystal. The methylcarboxylate group faces
the acetonitrile ligand in an exo-disposition, pointing away
from the Cp* group in order to minimize steric repulsions.
The closest contacts between the methyl acrylate ligand and
Conclusions
We can conclude that the products of the reactions of
[Cp*Ru(MeCN)2(PR1 NHR2)]+ with alkynes are sensitive
2
to the nature of the substituents in the aminophosphane
ligand and in the alkyne. In some cases amidobutadiene
complexes are generated by N–H activation, consistent with
the behavior observed for their Cp counterparts. However,
in other cases an alternative reaction pathway involving C–
H activation is feasible. This process most likely involves
orthometalation of the phenyl ring of an NHPh group and
formation of RuIV hydrido species which are intermediates
in the formation of the final products: η2-alkene complexes
formally derived from the insertion of one alkyne into the
ortho-C–H bond of the NHPh group. Given the fact that
the η2-MeOOCCH=CH2 ligand in the complex [Cp*Ru(η2-
MeOOCCH=CH2)(MeCN)(PPh2NHPh)]+ (6) behaves as a
good leaving group, it is reasonable to assume that the new
ligands iPr2PNHC6H4CH=CHR (R = nBu, SiMe3) in com-
plexes 4 and 5 should display a hemilabile character,[15] and
hence their complexes might have potential catalytic ac-
tivity, a possibility which is currently under investigation.
Experimental Section
General: All synthetic operations were performed under dry dini-
trogen or argon following conventional Schlenk techniques. Tetra-
hydrofuran, diethyl ether, and petroleum ether (boiling point range
40–60 °C) were distilled from the appropriate drying agents. All
solvents were deoxygenated immediately before use. The complex
[Cp*Ru(MeCN)3][PF6] was obtained according to the literature.[16]
The ligands PPh2NHPh, PiPr2NHPh, and PiPr2NHC6F5, were pre-
pared following suitable adaptations of published procedures.[17–21]
1-Alkynes, diynes, and methyl acrylate were purchased from Ald-
rich and used as received. NMR spectra were recorded on a Varian
Unity 400 MHz or Varian Gemini 300 MHz spectrometer. Chemi-
cal shifts are given in ppm relative to SiMe4 (1H and 13C{1H}), 85%
H3PO4 (31P{1H}), or CFCl3 (19F). Microanalysis was performed
on an elemental analyzer model LECO CHNS-932 at the Servicio
Central de Ciencia y Tecnología, Universidad de Cádiz.
Figure 5. ORTEP drawing (50% thermal ellipsoids) of the cation
[Cp*Ru(MeCN)(η2-MeOOCCH=CH2)(PiPr2NHPh)]+ in complex
6. Hydrogen atoms have been omitted. Selected bond lengths [Å]
and angles [°] with estimated standard deviations in parentheses:
Ru1–C2 2.200(5), Ru1–C1 2.215(5), Ru1–C3 2.229(5), Ru1–C4
2.245(5), Ru1–C5 2.282(6), Ru1–P1 2.342(1), Ru1–C11 2.185(5),
Ru1–C12 2.181(5), Ru1–N1 2.063(4), C11–C12 1.411(7), C11–C40
1.456(8), N1–C14 1.143(7), N2–P1 1.675(5); Ru1–P1–N2 112.1(2),
Ru1–N1–C14 173.0(5), C12–C11–C40 121.3(5).
[Cp*Ru(MeCN)2(PR1 NHR2)][PF6] (R1 = R2 = Ph 1; R1 = iPr, R2
2
= C6F5 2): A stoichiometric amount of either PPh2NHPh for 1
(1.67 g, 6 mmol), or iPr2PNHC6F5 for 2 (1.79 g, 6 mmol), was
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C–H vs. N–H Bond Activation in Aminophosphane Ligands
FULL PAPER
added to a solution of [Cp*Ru(MeCN)3][PF6] (3 g, ca. 6 mmol) in
dichloromethane (25 mL). The mixture was stirred at room tem-
perature for 1 h. The solvent was then removed in vacuo. The resi-
due was washed with several portions of diethyl ether, and finally
with one portion of petroleum ether to give a yellow powder, which
was dried in vacuo.
1: Yield: 4 g, ca. 90%. C32H37F6N3P2Ru: calcd. C 51.89, H 5.04, N
5.7; found C 52.1, H 5.15, N 5.4. 1H NMR (CD3COCD3, 298 K): δ
= 1.45 [d, JH,P = 1.5 Hz, 15 H, C5(CH3)5], 2.41 (d, JH,P = 1.5 Hz,
6 H, CH3CN), 5.66 (d, JH,P = 13.8 Hz, 1 H, NH), 6.74, 7.01, 7.46,
7.71 (m, 15 H, C6H5) ppm. 13C{1H} NMR (CD3COCD3, 298 K):
δ = 3.6 (s, CH3CN), 9.1 [s, C5(CH3)5], 87.9 [d, JC,P = 2.4 Hz,
C5(CH3)5], 119.1, 126.6, 128.7, 129.0, 130.4, 132.2 (C6H5) ppm.
31P{1H} NMR (CD3COCD3, 298 K): δ = 78.7 ppm (s).
[Cp*Ru{η4-C4H3(CH2)3PPh2NPh-κ1N}][PF6] (1b): This compound
was obtained in a fashion analogous to 1a, but using 1,6-hep-
tadiyne instead of propargyl ether. Yield: 53%. C35H39F6NP2Ru:
calcd. C 56.00, H 5.24, N 1.9; found C 55.8, H 5.04, N 1.8. 1H
NMR (CD3COCD3, 298 K): δ = 1.37 (m, 2 H, CH2), 1.68 [s, 15
H, C5(CH3)5], 2.42 (m, 2 H, CH2), 2.75 (d, JH,H = 3.1 Hz, 1 H,
H4endo), 3.48 (m, 2 H, CH2), 4.10 (d, JH,P = 16.9 Hz, 1 H, H1), 4.76
(d, JH,H = 3.1 Hz, 1 H, H4exo), 6.68–8.00 (m, 15 H, C6H5) ppm.
13C{1H} NMR (CD3COCD3, 298 K): δ = 9.6 [s, C5(CH3)5], 21.1
(s, CH2), 26.5 (d, JC,P = 112.7 Hz, C1), 36.2 (s, CH2), 38.0 (d, JC,P
= 12 Hz, CH2), 51.8 (s, C4), 98.8 [s, C5(CH3)5], 99.9 (s, C3), 115.3
(s, C2), 120.2, 120.7, 124.0, 129.5, 129.9, 130.4, 132.4, 132.6, 134.7,
134.9, 142.6 (C6H5) ppm. 31P{1H} NMR (CD3COCD3, 298 K): δ
= 47.7 ppm (s).
2: Yield: 3.4 g, ca. 75%. C26H36F11N3P2Ru: calcd. C 40.95, H 4.76,
1
N 5.5; found C 40.8, H 4.88, N 5.3. H NMR (CDCl3, 298 K): δ
= 1.61 [s, 15 H, C5(CH3)5], 1.0–1.2 [m, 12 H, P{CH(CH3)2}2], 2.39
[m, 2 H, P{CH(CH3)2}2], 2.41 (s, 6 H, CH3CN), 3.41 (d, JH,P
=
12.7 Hz, 1 H, NH) ppm. 13C{1H} NMR (CDCl3, 298 K): δ = 3.9
(s, CH3CN), 10.3 [s, C5(CH3)5], 17.4 [s, P{CH(CH3)2}2], 29.0 [d,
JC,P = 21.3 Hz, P{CH(CH3)2}2], 86.0 [s, C5(CH3)5] ppm. 19F NMR
(CDCl3, 298 K): δ = –146.6, –161.0, –163.8 ppm. 31P{1H} NMR
(CDCl3, 298 K): δ = 116.5 ppm (s).
[Cp*Ru{η4-C4H3(CH2)4PPh2NPh-κ1N}][PF6] (1c): This compound
was obtained in a fashion analogous to 1a, but using 1,7-octadiyne
instead of propargyl ether. Yield: 43%. C36H41F6NP2Ru: calcd. C
56.54, H 5.40, N 1.8; found C 56.5, H 5.33, N 1.8. 1H NMR
(CD3COCD3, 298 K): δ = 1.48 (m, 2 H, CH2), 1.69 [s, 15 H,
C5(CH3)5], 1.95 (m, 2 H, CH2), 2.23 (m, 2 H, CH2), 2.60 (d, JH,H
= 2.8 Hz, 1 H, H4endo), 3.13 (m, 2 H, CH2), 3.71 (d, JH,P = 14 Hz,
1 H, H1), 4.62 (d, JH,H = 2.8 Hz, 1 H, H4exo), 6.8–7.9 (m, 15 H,
C6H5) ppm. 13C{1H} NMR (CD3COCD3, 298 K): δ = 10.0 [s,
C5(CH3)5], 22.0, 22.3 (s, CH2), 28.2 (d, JC,P = 109 Hz, C1), 31.4,
31.5 (s, CH2), 54.1 (s, C4), 99.7 [s, C5(CH3)5], 108.7 (s, C3), 115.8
(s, C2), 121.5, 125.3, 129.4, 129.8, 130.5, 132.3, 132.6, 134.6, 135.0,
143.2 (C6H5) ppm. 31P{1H} NMR (CD3COCD3, 298 K): δ =
50.6 ppm (s).
[Cp*Ru(MeCN)2(PiPr2NHPh)][BPh4] (3): This compound was pre-
pared in a fashion analogous to that for 1 and 2, starting from
[Cp*Ru(MeCN)3][PF6] (1.5 g, ca. 3 mmol) and a stoichiometric
amount of iPr2PNHPh (1.2 mL, 3 mmol) in dichloromethane
(20 mL). The solvent was removed in vacuo and the residue washed
with diethyl ether. Then, it was conveniently transformed into its
[BPh4]– salt by addition of MeOH and an excess of solid NaBPh4
(1.5 g). The yellow precipitate was filtered, washed with EtOH and
petroleum ether, and dried in vacuo. Yield: 2.16 g, 85%.
C50H61BN3PRu: calcd. C 70.91, H 7.26, N 5.0; found C 70.8, H
7.15, N 4.9. 1H NMR (CD3COCD3, 298 K): δ = 1.45 [d, JH,P
=
1.5 Hz, 15 H, C5(CH3)5], 2.41 (d, JH,P = 1.5 Hz, 6 H, CH3CN),
5.66 (d, JH,P = 13.8 Hz, 1 H, NH), 6.74, 7.01, 7.46, 7.71 (m, 15 H,
C6H5) ppm. 13C{1H} NMR (CDCl3, 298 K): δ = 3.2 (s, CH3CN),
10.8 [s, C5(CH3)5], 18.2, 18.3 [s, P{CH(CH3)2}2], 29.7 [d, JC,P
=
[Cp*Ru(η4-C4H5PPh2NPh-κ1N)][PF6] (1d): Acetylene was bubbled
through a solution of 1 (0.37 g, 0.5 mmol) in dichloromethane
(15 mL) and the mixture was stirred under acetylene for 1 h at
room temperature. The solution was then filtered in order to re-
move a black solid in suspension [most likely poly(acetylene)]. The
solvent was removed in vacuo, and the residue washed with two
portions of diethyl ether and one portion of petroleum ether. A
red-orange powder was obtained, which was filtered off and dried
in vacuo. It was recrystallized from a mixture of acetone and petro-
leum ether. Yield: 0.19 g, ca. 54%. C32H35F6NP2Ru: calcd. C 54.08,
H 4.96, N 2.0; found C 53.8, H 5.06, N 1.8. 1H NMR (CDCl3,
298 K): δ = 1.66 [s, C5(CH3)5], 2.45 (dd, JH,H = 11, JH,HЈ = 2.7 Hz,
1 H, H4endo), 3.63 (dd, JH,P = 16.3, JH,H = 9.9 Hz, 1 H, H1), 4.47
(dd, JH,H = 9.2, JH,HЈ = 2.7 Hz, 1 H, H4exo), 5.41 (m, 1 H, H3),
5.88 (ddd, JH,P = 28, JH,H = 9.9, JH,HЈ = 7.5 Hz, 1 H, H2), 6.64–
7.76 (m, C6H5) ppm. 13C{1H} NMR (CDCl3, 298 K): δ = 9.8
[C5(CH3)5], 31.5 (d, JC,P = 112.2 Hz, C1), 58.2 (s, C4), 98.2 (s, C3),
98.9 [C5(CH3)5], 103.8 (s, C2), 120.6, 123.4, 123.5, 128.8, 129.1,
129.2, 129.6, 129.7, 131.2, 131.3, 131.4, 133.9, 134.2, 142.6 (C6H5)
ppm. 31P{1H} NMR (CDCl3, 298 K): δ = 41.6 ppm (s).
20.6 Hz, P{CH(CH3)2}2], 93.5 [s, C5(CH3)5], 121.6, 126.0, 135.7
(C6H5) ppm. 31P{1H} NMR (CD3COCD3, 298 K): δ = 101.1 ppm
(s).
[Cp*Ru{η4-C4H3(CH2OCH2)PPh2NPh-κ1N}][PF6] (1a): A slight
excess over the stoichiometric amount of propargyl ether (57 μL,
0.55 mmol) was added to a solution of 1 (0.37 g, 0.5 mmol) in
dichloromethane (12 mL) and the mixture was stirred for 1 h at
room temperature. The solvent was then removed in vacuo, and the
residue washed with two portions of diethyl ether and one portion
of petroleum ether. A red-orange powder was obtained, which was
filtered off and dried in vacuo. It was recrystallized from a mixture
of acetone and petroleum ether. Yield: 0.16 g, 44%. C34H37F6NO-
P2Ru: calcd. C 54.26, H 4.95, N 1.9; found C 53.9, H 5.04, N 1.7.
1H NMR (CD3COCD3, 298 K): δ = 1.67 [s, 15 H, C5(CH3)5], 2.79
(d, JH,H = 3.1 Hz, 1 H, H4endo), 4.32, 5.15 (d, JH,H = 13.2 Hz, 1 H
each, CH2), 4.35, 5.26 (d, JH,H = 12.8 Hz, 1 H each, CH2), 4.47 (d,
JH,P = 17.6 Hz, 1 H, H1), 4.94 (d, JH,H = 3.1 Hz, 1 H, H4exo), 6.68–
8.00 (m, 15 H, C6H5) ppm. 13C{1H} NMR (CD3COCD3, 298 K):
δ = 9.7 [s, C5(CH3)5], 26.6 (d, JC,P = 115.5 Hz, C1), 50.0 (s, C4),
75.1 (s, CH2), 75.7 (d, JC,P = 11.4 Hz, CH2), 86.3 (s, C3), 99.4 [s,
[Cp*Ru{η4-C4H3(nBu)2PPh2NPh-κ1N}][PF6]
(1e):
1-Hexyne
C5(CH3)5], 114.8 (s, C2), 120.7, 123.6, 123.8, 129.6, 130.5, 132.4, (126 μL, 1.10 mol) was added to a solution of 1 (0.37 g, 0.5 mmol)
132.6, 132.7, 134.9, 135.1, 142.4 (C6H5) ppm. 31P{1H} NMR
(CD3COCD3, 298 K): δ = 42.7 ppm (s).
in dichloromethane (15 mL) and the mixture was stirred for 1 h at
room temperature. The solvent was then removed in vacuo, and the
Eur. J. Inorg. Chem. 2005, 2631–2640
www.eurjic.org
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2637

M. Jiménez-Tenorio, M. C. Puerta, P. Valerga
FULL PAPER
residue washed with two portions of diethyl ether and one portion
of petroleum ether. A yellow-orange powder was obtained, which
was filtered off and dried in vacuo. It was recrystallized from a
mixture of acetone and petroleum ether. Yield: 0.14 g, 35%.
C40H51F6NP2Ru: calcd. C 58.39, H 6.25, N 1.7; found C 58.2, H
1.74, 2.32 [m, 1 H each, P{CH(CH3)2}2], 2.63 (d, JH,H = 3.6 Hz, 1
H, H4endo), 3.20 (d, JH,P = 16 Hz, 1 H, H1), 3.69, 4.64 (d, JH,H
=
13.6 Hz, 1 H each, CH2), 3.79, 4.75 (d, JH,H = 13.6 Hz, 1 H each,
CH2), 4.06 (d, JH,H = 3.6 Hz, 1 H, H4exo), 6.36, 6.73, 7.02 (m, 5 H,
C6H5) ppm. 13C{1H} NMR (CDCl3, 298 K): δ = 9.5 [s, C5(CH3)5],
16.2, 16.3, 16.8, 17.5 [s, P{CH(CH3)2}2], 16.5 (d, JC,P = 104.3 Hz,
C1), 31.6 [d, JC,P = 47.7 Hz, P{CH(CH3)2}], 32.3 [d, JC,P = 34 Hz,
P{CH(CH3)2}], 47.9 (s, C4), 74.6 (s, CH2), 74.9 (d, JC,P = 9 Hz,
CH2), 98.2 [s, C5(CH3)5], 108.7 (s, C3), 113.5 (s, C2), 120.6, 122.7,
129.0, 142.2 (C6H5) ppm. 31P{1H} NMR (CDCl3, 298 K): δ =
1
6.12, N 1.6. H NMR (CDCl3, 298 K): δ = 1.58 [s, C5(CH3)5], 3.39
(m, 1 H, H4), 3.45 (d, JH,P = 15.9 Hz, 1 H, H1), 5.10 (d, JH,H
=
11.3 Hz, 1 H, H3), 6.58–7.70 (m, C6H5) ppm. 13C{1H} NMR
(CDCl3, 298 K): δ = 9.8 [s, C5(CH3)5], 13.7, 13.9 [s, (CH2)3CH3],
21.7 (s), 22.4 (s), 33.5 (s), 34.5 (s), 35.8 (s), 41.7 (d, JC,P = 9.8 Hz)
[(CH2)3CH3], 29.6 (d, JC,P = 112.2 Hz, C1), 81.9 (s, C4), 96.5 76.7 ppm (s).
[C5(CH3)5], 99.5 (s, C3), 116.1 (s, C2), 120.6, 123.2, 123.4, 128.7,
[Cp*Ru{η4-C4H3(CH2CH2CH2)PiPr2NPh-κ1N}][BPh4] (3b): This
128.9, 129.0, 129.7, 129.8, 131.0, 133.7, 134.3, 142.6 (C6H5) ppm.
31P{1H} NMR (CDCl3, 298 K): δ = 42.4 ppm (s).
compound was obtained in a fashion analogous to 3a, but using
1,6-heptadiyne instead of propargyl ether. Yield: 55%.
C58H63BNPRu: calcd. C 75.97, H 6.92, N 1.5; found C 76.1, H
7.04, N 1.5. 1H NMR (CDCl3, 298 K): δ = 0.78, 0.91, 1.37, 1.49
[m, 3 H each, P{CH(CH3)2}2], 1.22 (m, 2 H, CH2), 1.53 [s, 15 H,
C5(CH3)5], 2.11 (m, 2 H, CH2), 1.92, 2.55 [m, 1 H each,
P{CH(CH3)2}2], 2.75 (d, JH,H = 3.2 Hz, 1 H, H4endo), 3.19 (m, 2 H,
CH2), 3.53 (d, JH,P = 16 Hz, 1 H, H1), 4.21 (d, JH,H = 3.2 Hz, 1
H, H4exo), 6.51, 7.11, 7.21 (m, 5 H, C6H5) ppm. 13C{1H} NMR
(CDCl3, 298 K): δ = 9.6 [s, C5(CH3)5], 16.2, 16.7, 16.9, 17.8 [s,
P{CH(CH3)2}2], 17.9 (d, JC,P = 103 Hz, C1), 20.3 (s, CH2), 31.7,
32.3 [m, P{CH(CH3)2}2], 36.0 (s, CH2), 37.1 (d, JC,P = 7.8 Hz,
[Cp*Ru{η4-C4H3(CH2OCH2)PiPr2NC6F5-κ1N}][PF6] (2a): Propar-
gyl ether (57 μL, 0.55 mmol) was added to a solution of 2 (0.38 g,
ca. 0.5 mmol) in dichloromethane (12 mL) and the mixture was
stirred for 1 h at room temperature. The solvent was then removed
in vacuo, and the residue washed with two portions of diethyl ether
and one portion of petroleum ether. A red-orange powder was ob-
tained, which was filtered off and dried in vacuo. It was recrys-
tallized from a mixture of acetone and petroleum ether. Yield:
0.16 g, ca. 42%. C28H36F11NOP2Ru: calcd. C 43.42, H 4.68, N 1.8;
1
found C 43.3, H 4.77, N 1.5. H NMR (CDCl3, 298 K): δ = 0.90,
1.34, 1.54 [m, 12 H, P{CH(CH3)2}2], 1.49 [s, 15 H, C5(CH3)5], 2.49 CH2), 49.9 (s, C4), 93.5 (s, C3), 97.4 [s, C5(CH3)5], 113.7 (s, C2),
[m, 2 H, P{CH(CH3)2}2], 3.61 (d, JH,H = 4.5 Hz, 1 H, H4endo), 4.11, 119.6, 120.4, 123.1, 126.0, 135.7, 142.8 (C6H5) ppm. 31P{1H} NMR
5.14 (d, JH,H = 13.2 Hz, 1 H each, CH2), 4.29, 5.12 (d, JH,H
=
(CDCl3, 298 K): δ = 77.9 ppm (s).
14.2 Hz, 1 H each, CH2), 4.38 (d, JH,P = 16.5 Hz, 1 H, H1), 4.41 (d,
JH,H = 4.5 Hz, 1 H, H4exo) ppm. 13C{1H} NMR (CDCl3, 298 K): δ
= 8.9 [s, C5(CH3)5], 14.9, 15.6, 16.4, 17.0 [s, P{CH(CH3)2}2], 19.7
(d, JC,P = 105 Hz, C1), 31.5 [d, JC,P = 44 Hz, P{CH(CH3)2}2], 32.1
[d, JC,P = 42 Hz, P{CH(CH3)2}2], 48.1 (s, C4), 74.8 (s, CH2), 75.2
(d, JC,P = 8.9 Hz, CH2), 98.4 [s, C5(CH3)5], 114.0 (s, C2) ppm.19F
NMR (CDCl3, 298 K): δ = –144.1, –162.3, –162.7 ppm. 31P{1H}
NMR (CDCl3, 298 K): δ = 84.7 ppm (s).
[Cp*Ru{η4-C4H3(CH2)4-PiPr2NPh-κ1N}][BPh4] (3c): This com-
pound was obtained in a fashion analogous to 3a, but using 1,7-
octadiyne instead of propargyl ether. Yield: 48%. C59H65BNPRu:
calcd. C 76.11, H 7.04, N 1.5; found C 76.1, H 6.98, N 1.4. 1H
NMR (CDCl3, 298 K): δ = 0.64, 0.74, 1.04, 1.34 [s, 3 H each,
P{CH(CH3)2}2], 1.12 (m, 2 H, CH2), 1.34 [s, 15 H, C5(CH3)5], 1.69
(m, 2 H, CH2), 1.72, 2.26 [m, 1 H each, P{CH(CH3)2}], 2.54 (m, 2
H, CH2), 2.57 (d, JH,H = 3.2 Hz, 1 H, H4endo), 2.74 (m, 2 H, CH2),
[Cp*Ru{η4-C4H3(CH2CH2CH2)PiPr2NC6F5-κ1N}][PF6] (2b): This 2.79 (d, JH,P = 13.6 Hz, 1 H, H1), 3.97 (d, JH,H = 3.2 Hz, 1 H,
compound was obtained in a fashion analogous to 2a, but using
1,6-heptadiyne instead of propargyl ether. Yield: 50%.
C29H38F11NP2Ru: calcd. C 45.08, H 4.96, N 1.8; found C 44.8, H
H4exo), 6.45, 7.02, 7.11 (m, 5 H, C6H5) ppm. 13C{1H} NMR
(CDCl3, 298 K): δ = 9.8 [s, C5(CH3)5], 14.8, 16.4, 17.6, 17.7
[P{CH(CH3)2}2], 20.4 (d, JC,P = 98.6 Hz, C1), 21.0, 21.4 (s, CH2),
30.7 (d, JC,P = 8.1 Hz, CH2), 30.9 (s, CH2), 32.2 [d, JC,P = 48.5 Hz,
1
5.06, N 1.7. H NMR (CDCl3, 298 K): δ = 0.87, 1.32, 1.54 [m, 12
H, P{CH(CH3)2}2], 1.21 (m, 2 H, CH2), 1.45 [s, 15 H, C5(CH3)5], P{CH(CH3)2}], 32.6 [d, JC,P = 43 Hz, P{CH(CH3)2}], 50.9 (s, C4),
2.01, 2.16 [m, 1 H each, P{CH(CH3)2}], 2.62, 3.26 (m, 2 H each, 98.3 [s, C5(CH3)5], 106.8 (s, C3), 114.6 (s, C2), 123.0, 124.4, 128.9,
CH2) 3.59 (d, JH,H = 4.6 Hz, 1 H, H4endo), 4.14 (d, JH,P = 16.4 Hz,
135.7, 142.6 (C6H5) ppm. 31P{1H} NMR (CDCl3, 298 K): δ =
1 H, H1), 4.37 (d, JH,H = 4.6 Hz, 1 H, H4exo) ppm. 13C{1H} NMR 81.7 ppm (s).
(CDCl3, 298 K): δ = 8.7 [s, C5(CH3)5], 14.7, 15.8, 16.2 [s,
[Cp*Ru(MeCN){η2-nBuCH=CH(C6H4)NHPiPr2-κ1P}][BPh4] (4):
P{CH(CH3)2}2], 20.3 (s, CH2), 21.5 (d, JC,P = 102.8 Hz, C1), 31.5
[d, JC,P = 44.5 Hz, P{CH(CH3)2}], 34.0 [d, JC,P = 39.8 Hz,
P{CH(CH3)2}], 35.4 (s, CH2), 36.6 (d, JC,P = 7.7 Hz, CH2), 54.6 (s,
C4), 97.0 [s, C5(CH3)5], 116.4 (s, C2) ppm. 19F NMR (CDCl3,
298 K): δ = –144.0, –162.4, –163.2 ppm. 31P{1H} NMR (CDCl3,
298 K): δ = 85.1 ppm (s).
1-Hexyne (65 μL, ca. 0.57 mmol) was added to a solution of 3
(0.42 g, 0.5 mmol) in 1,2-dichloroethane (8 mL). The mixture was
stirred for 5 min at 60 °C and then for 1 h at room temperature.
The solvent was removed in vacuo, and the residue washed with
diethyl ether and petroleum ether until a yellow-orange powder was
obtained. This material was filtered off and dried in vacuo. Yellow
crystals of 4·Me2CO were obtained by recrystallization of the crude
material from acetone/petroleum ether. Yield: 0.18 g, 40%.
C57H74BN2OPRu: calcd. C 72.36, H 7.88, N 3.0; found C 72.2, H
[Cp*Ru{η4-C4H3(CH2OCH2)PiPr2NPh-κ1N}][BPh4] (3a): Propar-
gyl ether (57 μL, 0.55 mmol) was added to a solution of 3 (0.42 g,
ca. 0.5 mmol) in dichloromethane (15 mL) and the mixture was
stirred for 1 h at room temperature. The solvent was then removed
in vacuo, and the residue washed with two portions of diethyl ether
and one portion of petroleum ether. A yellow-orange powder was
obtained, which was filtered off and dried in vacuo. It was recrys-
tallized from a mixture of acetone and petroleum ether. Yield:
0.22 g, 48%. C57H61BNOPRu: calcd. C 74.50, H 6.69, N 1.5; found
C 74.2, H 6.58, N 1.3. 1H NMR (CDCl3, 298 K): δ = 0.60, 0.71,
1
7.73, N 2.9. H NMR (CDCl3, 298 K): δ = 1.15 (s, 3 H, CH3CN),
1.19 [d, JH,P = 1.5 Hz, 15 H, C5(CH3)5], 0.87, 1.20, 1.33, 1.54 [m,
3 H each, P{CH(CH3)2}2], 0.92, 1.51, 1.76 [m, 2 H each, (CH2)
CH3], 1.00 [t, JH,H = 7.3 Hz, 3 H, (CH2)CH3], 2.45, 2.70 [m, 1 H
each, P{CH(CH3)2}2], 3.80 (m, 1 H, =CHnBu), 3.84 (m, 1 H, =
CHC6H4), 4.89 (s, 1 H, NH), 6.64, 6.70, 7.02, 7.21 (m, 1 H each,
C6H4) ppm. 13C{1H} NMR (CDCl3, 298 K): δ = 2.8 (s, CH3CN),
1.10, 1.27 [m, 3 H each, P{CH(CH3)2}2], 1.37 [s, 15 H, C5(CH3)5], 8.9 [s, C5(CH3)5], 14.2 [s, (CH2)3CH3], 16.6, 18.2, 20.4, 21.5
2638 © 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim www.eurjic.org
Eur. J. Inorg. Chem. 2005, 2631–2640

C–H vs. N–H Bond Activation in Aminophosphane Ligands
FULL PAPER
[P{CH(CH3)2}2], 22.5, 33.6, 35.7 [s, (CH2)3CH3], 32.5 [t, JC,P
=
15.9 Hz, 1 H, NH), 6.43, 6.68, 6.91 (m, 5 H, NHC6H5), 7.40–7.62
21.9 Hz, P{CH(CH3)2}2], 57.4 (d, JC,P = 11 Hz, =CHnBu), 67.1 (s, [m, 10 H, P(C6H5)2] ppm. 13C{1H} NMR (CDCl3, 298 K): δ = 3.7
=CHC6H4), 93.8 [s, C5(CH3)5], 116.5, 118.7, 128.1, 128.2, 135.7,
(s, CH3CN), 8.3 [s, C5(CH3)5], 46.6 (d, JC,P = 5.4 Hz, =CH2), 52.1
(d, JC,P = 17 Hz, =CHCOOCH3), 52.3 (s, COOCH3), 98.0 [s,
C5(CH3)5], 118.3, 120.8, 128.8, 128.9, 129.0, 129.1, 131.4, 131.7,
132.0, 132.1, 142.7 (C6H5), 178.1 (COOCH3) ppm. 31P{1H} NMR
(CDCl3, 298 K): δ = 76.4 ppm (s).
142.9 (C6H4) ppm. 31P{1H} NMR (CDCl3, 298 K): δ = 101.7 ppm
(s).
[Cp*Ru(MeCN){η2-Me3SiCH=CH(C6H4)NHPiPr2-κ1P}][BPh4] (5):
This compound was obtained in a fashion analogous to 4, but
using HCϵCSiMe3 instead of 1-hexyne. Yield: 53%.
C53H68BN2PRuSi: calcd. C 70.41, H 7.58, N 3.1; found C 70.2, H
X-ray Structure Determinations: Crystal data and experimental de-
tails are given in Table 1. X-ray diffraction data were collected on
a Bruker SMART APEX three-circle diffractometer (graphite-mo-
nochromated Mo-Kα radiation, λ = 0.71073 Å) with a CCD area
1
7.64, N 3.0. H NMR (CDCl3, 298 K): δ = 0.01 [s, 9 H, Si(CH3)3],
0.93 (d, JH,P = 1 Hz, 3 H, CH3CN), 1.07 [d, JH,P = 1.5 Hz, 15 H,
C5(CH3)5], 0.90, 1.04, 1.28, 1.42 [m, 3 H each, P{CH(CH3)2}2], detector at the Servicio Central de Ciencia y Tecnología de la Uni-
2.27, 2.61 [m, 1 H each, P{CH(CH3)2}2], 2.61 (m, 1 H, =CHSiMe3),
3.91 (m, 1 H, =CHC6H4), 4.81 (s, 1 H, NH), 6.53, 6.60, 6.83, 6.92
versidad de Cádiz. Hemispheres of the reciprocal space were mea-
sured by omega scan frames with δ(ω) 0.30°. Corrections for ab-
(m, 1 H each, C6H4) ppm. 13C{1H} NMR (CDCl3, 298 K): δ = 0.7 sorption and crystal decay (insignificant) were applied by semi-em-
[s, Si(CH3)3], 2.5 (s, CH3CN), 9.3 [s, C5(CH3)5], 17.0 (d), 19.0 (d),
20.6 (s), 21.1 [s, P{CH(CH3)2}2], 32.9, 34.5 [d, JC,P = 24.4 Hz, The structures were solved by direct methods, completed by subse-
pirical methods from equivalents using the program SADABS.[22]
P{CH(CH3)2}2], 54.0 [s, =CHSi(CH3)3], 62.1 (d, JC,P = 9.8 Hz,
=CHC6H4), 94.4 [s, C5(CH3)5], 116.4, 118.8, 127.8, 128.2, 129.8,
143.3 (C6H4) ppm. 31P{1H} NMR (CDCl3, 298 K): δ = 107.7 ppm
(s).
quent difference Fourier synthesis, and refined on F2 by full-matrix
least-squares procedures using the program SHELXTL.[23] The li-
gand iPr2PNH(C6H4)CH=CHnBu in compound 4 showed orienta-
tion disorder at the end of the nBu group. The set C(15)H2 and
C(16)H3 was refined as two ethyl groups in complementary posi-
tions. Final refinements gave approximately 50% of each position.
In this compound all non-hydrogen atoms except C15 and C15b
were refined anisotropically, and hydrogen atoms were included at
idealized positions and refined using a riding model. In the case of
compounds 1a, 2a, and 6, all non-hydrogen atoms were refined
with anisotropic displacement coefficients, and all the remaining
hydrogen atoms were refined using the SHELX riding model. The
program ORTEP-3[24] was used for plotting.
[Cp*Ru(MeCN)(η2-MeOOCCH=CH2)(PPh2NHPh)][PF6] (6): An
excess of methyl acrylate (180 μL, ca. 1 mmol) was added to a solu-
tion of 1 (0.37 g, 0.5 mmol) in dichloromethane (10 mL) and the
mixture was stirred for 30 min at room temperature. It was then
filtered through celite and layered with petroleum ether. Yellow
crystals of 6 were obtained after 3–4 days. The crystals were sepa-
rated from the liquor, washed with petroleum ether, and dried in
vacuo. Yield: 0.22 g, 56%. C34H40F6N2O2P2Ru: calcd. C 51.97, H
5.13, N 3.6; found C 51.9, H 5.14, N 3.5. IR: ν(C=O) = 1687 cm–1.
1H NMR (CDCl3, 298 K): δ = 1.34 [d, JH,P = 1.5 Hz, 15 H, CCDC260375 (for 1a), -260376 (for 2a), -260377 (for 4), and
C5(CH3)5], 2.44 (d, JH,P = 1.5 Hz, 3 H, CH3CN), 3.78 (s, CO-
-260378 (for 6) contain the supplementary crystallographic data for
OCH3), 2.61, 3.45, 3.52 (m, 1 H each, CH=CH2), 6.78 (d, JH,P
=
this paper. These data can be obtained free of charge from The
Table 1. Summary of crystallographic data for 1a, 2a, 4, and 6.
Compound
1a
2a
4
6
Formula
Mol. mass
C34H37F6NOP2Ru
752.66
C28H36F11NOP2Ru
774.59
C57H74BN2OPRu
946.03
C34H40F6N2O2P2Ru
785.69
T [K]
Crystal size [mm]
Crystal system
Space group
a [Å]
b [Å]
c [Å]
α [°]
100(2)
100(2)
100(2)
100(2)
0.44×0.31×0.28
orthorhombic
Pna21 (no. 33)
17.193(1)
10.3496(6)
17.812(1)
0.41×0.15×0.03
triclinic
0.23×0.22×0.06
monoclinic
P21/c (no.14)
12.366(2)
17.846(2)
23.178(3)
0.32×0.15×0.06
orthorhombic
Pna21 (no. 33)
21.133(1)
12.5882(7)
12.9869(7)
¯
P1 (no. 2)
8.378(2)
10.031(2)
17.976(4)
88.35(3)
86.22(3)
85.71(3)
1502.9(5)
2
β [°]
99.166(3)
γ [°]
V [Å3]
3169.4(3)
4
1.577
6.61
5049.8(1)
4
1.243
3.83
3454.8(3)
4
1.511
6.12
Z
ρcalc [gcm–3]
1.712
7.22
μ(Mo-Kα) [cm–1]
F(000)
1536
1.04–0.93
2.28 Ͻ θ Ͻ 27.56
27732
7085 (Rint = 0.0210)
7007
784
1–0.83
2.04 Ͻ θ Ͻ 25.06
12886
5265 (Rint = 0.0337)
4986
2008
0.98–0.73
1.67 Ͻ θ Ͻ 23.27
30663
7221 (Rint = 0.1075)
5948
1608
1.18–0.91
1.88 Ͻ θ Ͻ 27.52
30365
7385 (Rint = 0.0532)
7117
Max. and min. transmission factors
Theta range for data collection
Reflections collected
Unique reflections
No. of observed reflections [I Ͼ
2σ(I)]
No.of parameters
Final R1, wR2 values [I Ͼ 2σ(I)]
Final R1, wR2 values (all data)
Residual electron density peaks
(eÅ–3)
411
409
592
431
0.0206, 0.0529
0.0210, 0.0531
+0.508, –0.286
0.0413, 0.0821
0.0447, 0.0836
+0.573, –0.785
0.0959, 0.1743
0.1237, 0.1890
+0.611, –1.191
0.0524, 0.1171
0.0554, 0.1189
+0.921, –1.287
Eur. J. Inorg. Chem. 2005, 2631–2640
www.eurjic.org
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
2639

M. Jiménez-Tenorio, M. C. Puerta, P. Valerga
FULL PAPER
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Acknowledgments
We thank the Ministerio de Educación y Ciencia (DGI, Project
CTQ2004-00776/BQU) and the Junta de Andalucía (PAI FQM188)
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Received: January 12, 2005
Published Online: May 24, 2005
2640
© 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
Eur. J. Inorg. Chem. 2005, 2631–2640