Functionalized phosphorus analogues of the β-diketiminato ligand systems: Bis(N-arylphosphinimino)acetonitrile-derived complexes of rhodium and iridium

Article abstract of DOI:10.1039/b802032a

Staudinger reaction of dppm-CN (5) gave the corresponding bis(N-phenylphosphinimino)acetonitrile system (6). Deprotonation with LDA furnished the corresponding anionic ligand 9. Its reaction with [(CO) ₂RhCl]₂ gave the corresponding κ²N, N′-chelate complex 11. X-Ray diffraction revealed a non-planar boat-like conformation of the six-membered chelate ring in the crystal. Treatment of 9 with [(nbd)RhCl]₂ gave the six-membered chelate complex 12 which features a different twist-like structure in the solid state, as does 13, which was formed by reacting 9 with [(cod)IrCl]₂. The Royal Society of Chemistry 2008.

Full text of DOI:10.1039/b802032a

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Functionalized phosphorus analogues of the b-diketiminato ligand systems:
bis(N-arylphosphinimino)acetonitrile-derived complexes of rhodium
and iridium†
Kirsten Spannhoff, Gerald Kehr, Seda Kehr,‡ Roland Fro¨hlich‡ and Gerhard Erker*
Received 5th February 2008, Accepted 2nd April 2008
First published as an Advance Article on the web 14th May 2008
DOI: 10.1039/b802032a
Staudinger reaction of dppm-CN (5) gave the corresponding bis(N-phenylphosphinimino)acetonitrile
system (6). Deprotonation with LDA furnished the corresponding anionic ligand 9. Its reaction with
[(CO)2RhCl]2 gave the corresponding j2N,Nꢀ-chelate complex 11. X-Ray diffraction revealed a
non-planar boat-like conformation of the six-membered chelate ring in the crystal. Treatment of 9 with
[(nbd)RhCl]2 gave the six-membered chelate complex 12 which features a different twist-like structure in
the solid state, as does 13, which was formed by reacting 9 with [(cod)IrCl]2.
to the neutral chelate ligand bis(diphenylphosphino)acetonitrile
(dppm-CN) (5) by treatment with base (n-BuLi) followed by
Introduction
chlorodiphenylphosphine.13 We prepared a number of dppm-CN
derivatives14 and dppm-CN metal complexes. The Pd-systems
turned out to be very active catalysts e.g. in Suzuki–Miyaura
coupling reactions.13 The corresponding P-oxides and P-sulfides
(7, 8) were prepared (Scheme 2) and their corresponding mono-
lithium derivatives structurally investigated.15
Acetylacetonate (acac, 1) is a frequently used very versatile ligand
in transition metal chemistry.1 A variety of derivatives and ana-
logues have been developed, among them cyclic annulated systems
and other heteroatom derivatives.2 The N-arylimino derivatives,
the b-diketiminato or “nacnac” ligands (2), have found some
specific use and interest recently.3–5 The anions of the P-oxides,
P-sulfides and P-imines6–10 of bis(diphenylphosphino)methane
(dppm)11 might be regarded as heavy relatives of the acac and
the nacnac ligand family, respectively (see Scheme 1). We have
prepared a series of cyano-functionalized derivatives of these
systems.12 The neutral ligands are probably even more acidic
than the parent dppm systems. We have now used the bis(N-
arylimino)dppm-CN monoanion as a nacnac analogous ligand in
transition metal chemistry. We here report about the preparation
of first Group 9 metal complexes and describe their structural and
conformational features in the solid state.
Scheme 2
The Staudinger reaction16 of dppm-CN with phenyl azide gave
the corresponding bis-phosphinimine (6). It was shown to feature
an NH tautomeric form in the crystal and in solution.15 We have
now generated the corresponding mono-anion of 6 and used it for
the preparation of the respective Rh and Ir complexes.
Scheme 1
Results and discussion
This chemistry was initiated with the observation that ace-
tonitrile could readily be converted in a one pot procedure
The ligand system (6) was prepared by treatment of dppm-CN (5)
with phenyl azide as previously described by us.15 Its treatment
with LDA in THF gave the corresponding anionic ligand system
as its lithium salt (9) (Scheme 3). The product was isolated as a
very pale yellow solid that contained a little less than one equiv.
of THF. The 1H NMR spectrum of 9 (in d6-DMSO) features well
resolved and separated sets of signals of the phenyl groups at
phosphorus [d 7.60 (o), 7.22 (p), 7.09 (m)] and at nitrogen [d 7.05
(m), 6.85 (o), 6.53 (p)]. The 13C NMR resonance of the central
Organisch-Chemisches Institut der Universtia¨t Mu¨nster, Corrensstrasse 40,
48149, Mu¨nster, Germany. E-mail: erker@uni-muenster.de; Fax: +49 251
83 36503
† Electronic supplementary information (ESI) available: Details of the
spectroscopic characterization of compounds 9, 11, 12 and 13. CCDC
reference numbers 67924–67926. For crystallographic data in CIF or other
electronic format and ESI see DOI: 10.1039/b802032a
‡ X-Ray crystal structure analyses.
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Fig. 1 Molecular structure of complex 11.
Scheme 3
carbon atom C1 is found at d 18.0 (t, 1JPC = 97.8 Hz). The –CN
13C NMR resonance occurs at d 128.3. Compound 9 features a
prominent m(CN) IR band at 2159 cm−1. It shows a single 31P NMR
resonance at a typical chemical shift of d +4.8 (in d6-DMSO).17
The ligand system 9 was then reacted with the di(carbonyl)-
rhodium(I) chloride dimer [(CO)2RhCl]2 (10a) in toluene at room
temperature. After 12 h the reaction was worked up to give
the Rh-chelate complex 11 in 64% yield. The rhodium complex
features a 31P NMR signal at d 29.3 (in CD2Cl2).18 It shows a
single 13C NMR [Rh]-CO resonance at d 185.1 with a coupling
constant of 1JRhC = 69.9 Hz. Carbon atom C1 features a 13C NMR
The overall conformation of the chelate complex six-membered
framework is strongly deviating from planarity. It exhibits a pro-
nounced boat-shaped conformation (dihedral angles: Rh1–N2–
P2–C1: 3.3(2)◦, Rh1–N1–P1–C1: −32.0(2)◦, P1–N1 · · · N2–P2:
14.9◦, P1–C1–P2–N2: 63.0(2)◦, P2–C1–P1–N1: −44.9(2)◦, N1–
Rh1–N2–P2: −57.9(1)◦ N2–Rh1–N1–P1: 77.5(1)◦). The sums of
bond angles at N1 (353.8◦) and N2 (359.9◦) are close to a trigonal-
planar situation. The phosphorus atoms in complex 11 are pseudo-
tetrahedrally coordinated (angles N1–P1–C1: 104.8(1)◦, C41–P1–
C31: 105.4(1)◦, N2–P2–C1: 108.3(1)◦, C61–P2–C51: 108.8(1)◦).
The P–N as well as the adjacent P–C bonds inside the non-
planar six-membered ring structure are rather short (see above).
The coordination geometry of carbon atom C1 deviates only
marginally from trigonal-planar (angles P1–C1–P2: 119.5(2)◦,
P1–C1–C2: 117.6(2)◦, P2–C1–C2: 117.9(2)◦, R 355.0◦). The C1–
1
resonance at d 21.6 with a coupling constant JPC = 145.6 Hz,
which is markedly larger than observed for the precursor 9 (see
above). The cyano (C2) 13C NMR resonance occurs at d 123.1
2
1
with JPC = 9.3 Hz. Again the PPh2 and NPh H/13C phenyl
NMR resonances are nicely separated. They feature a single set
of signals for the pairs of phenyl groups at phosphorus indicating
rapid conformational equilibration of the framework in solution
at ambient temperature (for details see the Experimental section).
The Rh-carbonyl complex (11) shows a pair of prominent IR
m(CO) stretching bands at 2061 cm−1 and 1989 cm−1, respectively,
which is some 20 wavenumbers lower than was observed for
the “classical” [(acac)Rh(CO)2] reference system.19 Complex 11
features an IR m(CN) band at 2165 cm−1.
˚
˚
≡
C N unit is linear (C1–C2: 1.405(4) A, C2–N3: 1.140(4) A, angle
C1–C2–N3: 178.1(4)◦).
The pronounced boat-shaped conformation of 11 in the solid
state places the phenyl groups at each phosphorus atom in
markedly different environments. The C41–C46 Ph substituent
at P1 (and C51–C56 at P2) is oriented in a pseudo-equatorial
position at the framework, whereas the C31–C36 Ph group at P1
and the C61–C66 Ph substituent at P2 are oriented pseudoaxially.
We note that the planes of the latter are arranged almost parallel
to each other (see Fig. 1).
The reaction of the mono-anionic ligand 9 with [(nbd)RhCl]2
(10b) under similar conditions gave the corresponding (j2N,Nꢀ-
chelate ligand)Rh(I)(nbd) complex 12 (74% isolated). Single
crystals of 12 suited for the X-ray crystal structure analysis were
obtained from a toluene–pentane mixture at −35 ◦C. Complex
12 features a six-membered chelate complex framework. The
ligand system is j2N,Nꢀ-bonded to the Rh center. The Rh atom
is pseudo square-planar coordinated by the p-bonds of the
norbornadiene ligand and the pair of chelate ligand nitrogen
Complex 11 was characterized by an X-ray crystal structure
analysis (single crystals were obtained from a toluene–pentane
mixture at −35 ◦C). The structure (see Fig. 1) shows that both
nitrogen atoms of the monoanionic chelate ligand are bonded to
˚
˚
Rh (Rh1–N2: 2.125(2) A, Rh1–N1: 2.117(2) A, angle N1–Rh1–
N2: 87.6(1)◦). The Rh atom features a square-planar coordination
environment. It has a pair of cis-CO ligands bonded to it (Rh1–
◦
˚
˚
C3: 1.846(3) A, Rh1–C4: 1.846(3) A, angles C3–Rh1–C4: 88.5(1) ,
C4–Rh1–N1: 93.4(1)◦, C3–Rh1–N2: 90.5(1)◦). The angles at the
carbonyl carbon atoms amount to 177.6(3)◦ (Rh1–C4–O4) and
178.4(4)◦ (Rh1–C3–O3) (corresponding bond lengths C4–O4:
˚
atoms (N1A–Rh1A: 2.124(5) A [corresponding values of the
˚
˚
1.133(4) A, C3–O3: 1.130(4) A). The chelate ligand is delocalized
second independent molecule B are given in square brackets,
˚
˚
˚
but non-planar. It exhibits similar bond lengths for the pair of N–
N1B-Rh1B: 2.132(5) A], N2A–Rh1A: 2.135(5) A [2.106(5) A],
P bonds (N1–P1: 1.617(2) A, N2–P2: 1.620(2) A) and also for the
angle N1A–Rh1A–N2A: 92.2(2)◦ [91.9(2)◦]). The chelate ligand
˚
˚
˚
˚ ˚
is delocalized (N1A–P1A: 1.603(5) A [1.624(5) A], N2A–P2A:
pair of adjacent P1/P2–C1 linkages (P1–C1: 1.752(3) A, P2–C1:
˚
˚
˚
˚
˚
1.746(3) A).
1.599(5) A [1.612(5) A], P1A–C1A 1.741(6) A [1.740(6) A],
3340 | Dalton Trans., 2008, 3339–3344
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˚
˚
(angles C1A–P2A–N2A: 110.9(3)◦ [113.0(3)◦], C1A–P1A–N1A:
111.6(3)◦ [109.9(3)◦]).
P2A–C1A: 1.749(6) A [1.742(6) A]) but it is not planar. In
complex 12 the six-membered P2N2CRh ring system exhibits a
twist conformation (see Fig. 2 and Fig. 3). This orients the phenyl
In solution at room temperature complex 12 features NMR
spectra of a rapidly conformationally equilibrating ring system.
=
groups of the trigonally-planar P N nitrogen atoms toward
1
Consequently we observe a single set of H NMR resonances of
opposite sides of the framework. Carbon atom C1 is also planar-
tricoordinate (bond angles P1A–C1A–P2A: 115.8(3)◦ [115.0(3)◦],
P1A–C1A–C2A: 122.4(4)◦ [123.0(5)◦], P2A–C1A–C2A: 121.8(4)◦
[121.9(5)◦]). It has the linear CN substituent attached to it (C1A–
the two pairs of phenyl substituents at phosphorus and a separate
set of signals of the pair of N–Ph groups (for details see the
Experimental section). The 31P NMR resonance of complex 12
is at d 29.4. Complex 12 features a m(CN) IR band at 2148 cm−1.
We have also reacted an iridium(I) complex with the reagent
9. Treatment of the (cyclooctadiene)iridium chloride dimer
[(cod)IrCl]2 (10c) with the lithium salt 9 of the ligand system under
the usual conditions gave complex 13 as a yellow solid in 66% yield.
Complex 13 was characterized by X-ray diffraction. Single crystals
were obtained from a toluene–pentane mixture at −35 ◦C. The
j2N,Nꢀ-ligand core of 13 is almost isostructural to that of 12.
It features cis-coordination of the pair of nitrogen ligands to
˚
˚
˚
C2A: 1.402(9) A [1.394(9) A], C2A–N3A: 1◦.144(8) A [1.168(8)
◦
˚
A], angle C1A–C2A–N3A: 178.0(7) [179.4(9) ]). The phosphorus
atoms in 12 feature a pseudotetrahedral coordination geometry
˚
˚
iridium (N1–Ir: 2.122(2) A, N2–Ir: 2.136(2) A, angle N1–Ir–
N2: 90.2(1)◦). The metal center features a pseudo square-planar
coordination environment. The chelate ligand is electronically
degenerate; it features similar bond lengths for the pairs of P–N
˚
˚
and P–C1 vectors (P1–N1: 1.626(2) A/P2–N2: 1.618(2) A; P1–
˚
˚
C1: 1.744(3) A/P2–C1: 1.738(3) A). The six-membered chelate
complex framework exhibits a twist conformation (see Fig. 4).
Fig. 2 Molecular geometry of complex 12.
Fig. 4 A view of the molecular structure of the iridium complex
◦
˚
13. Selected bond lengths (A) and angles ( ): Ir–N1 2.122(2), Ir–N2
2.136(2), Ir–C3 2.124(3), Ir–C4 2.119(3), Ir–C7 2.125(3), Ir–C8 2.126(3),
N1–P1 1.626(2), N2–P2 1.618(2), P1–C1 1.744(3), P2–C1 1.738(3),
C1–C2 1.398(4), C2–N3 1.158(4), N1–C11 1.429(3), N2–C21 1.439(3),
P1–C31 1.819(3), P1–C41 1.805(3), P2–C51 1.808(3), P2–C61 1.814(3),
C3–C4 1.411(4), C4–C5 1.511(4), C5–C6 1.512(4), C6–C7 1.513(4),
C7–C8 1.400(4), C8–C9 1.509(4), C9–C10 1.519(5), C10–C3 1.518(5);
N1–Ir–N2 90.2(1), Ir–N1–P1 119.7(1), Ir–N1–C11 121.9(2), C11–N1–P1
118.3(2), N1–P1–C1 112.4(1), N1–P1–C31 110.5(1), N1–P1–C41
111.1(1), C1–P1–C31 109.9(1), C1–P1–C41 106.1(1), P1–C1–P2 115.9(2),
P1–C1–C2 119.9(2), P2–C1–C2 124.0(2), C1–C2–N3 178.1(3), C1–P2–N2
111.0(1), C1–P2–C51 110.4(1), C1–P2–C61 107.2(1), N2–P2–C51
110.4(1), N2–P2–C61 112.7(1), P2–N2–Ir 122.2(1), P2–N2–C21 118.3(2),
Ir–N2–C21 119.3(2), for additional values see the text.
At room temperature in solution (CD2Cl2) complex 13 shows
NMR spectra of a conformationally equilibrating system (for
Fig. 3 A comparison of the different conformational frameworks of the
j2N,Nꢀ-chelate Rh complexes 11 (boat, top) and 12 (twist, bottom).
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1
details see the Experimental section). The H NMR spectrum
the residue washed with pentane (three times, 30 ml each).
The solid light-yellow product was dried in vacuo (485 mg,
77%). Mp: 129 ◦C (DSC); Found: C, 74.79; H, 5.65; N, 6.23.
Calc. for C38H30LiN3P2·3/4thf: C, 75.57; H, 5.57; N, 6.45%);
mmax(KBr)/cm−1 3054, 3006, 2972, 2873, 2159, 1590, 1483, 1436,
1288, 1262, 1205, 1179, 1106, 1036, 1012, 746, 717 and 693;
dH(499.8 MHz; d6-DMSO; 298 K) 7.60 (m, 8H, o-PhP), 7.22 (m,
4H, p-PhP), 7.09 (m, 8H, m-PhP), 7.05 (m, 4H, m-PhN), 6.85 (m,
4H, o-PhN), 6.53 (m, 2H, p-PhN), 3.59 (m, 3H, a-THF) and 1.75 (m,
3H, b-THF); dC(125.7 MHz; d6-DMSO; 298 K) 153.6 (s, i-PhN),
135.3 (pd, 1JPC + 3JPC = 117.9 Hz, i-PhP), 132.3 (m, o-PhP), 129.5
(s, p-PhP), 128.3 (br. m, C2), 128.1 (s, m-PhN), 127.0 (m, m-PhP),
123.6 (m, o-PhN), 114.4 (s, p-PhN), 67.0 (s, a-THF), 25.1 (s, b-THF)
and 18.0 (t, 1JPC= 97.8 Hz, C1); dP{1H}(81.0 MHz; d6-DMSO; 298
K) 4.8 (s, m1/2 = 11.9 Hz).
of the cod ligand thus features only a set of three resonances at d
2.95 (m, 4H, -CH CH-) and d 2.00/1.24 (each m, R 8H, -CH2–
CH2-). The 13C NMR C1 resonance was located at d 24.6 (t) with
=
1
a coupling constant of JPC = 130.7 Hz. The corresponding C2
2
(i.e. –CN) carbon NMR signal occurs at d 124.1 (t, JPC = 7.9
Hz).15 Complex 13 features a prominent m(CN) IR stretching band
at 2154 cm−1.
Conclusions
We conclude that the mono-anionic ligand system 9 readily forms
j2N,Nꢀ-chelate complexes of the Group 9 metals Rh and Ir.
The resulting complexes are thermally very stable. Some of them
can even be handled for short periods of time in air without
appreciable decomposition. Thus, the new ligand system seems to
be similarly versatile and potentially useful as its acac or nacnac
congeners. Moreover, the ligand system 9 is readily available
due to the simple one-pot procedure of the formation of the
precursor dppm-CN (5). The metal complexes of the parent
bis(phosphinimino)methanide ligand (4, see Scheme 1) show a
variety of complex modes, ranging from j2N,Nꢀ through j2C,N
to j3C,N,Nꢀ coordination. It seems that the new mono-anionic
dppm-CN ligand in 9 is less C-nucleophilic as compared to the
parent 4, which is probably due to the carbanion stabilization by
the attached CN substituent. Consequently, in all three complexes
General procedure for the synthesis of the complexes 11, 12, and 13
Either [(CO)2RhCl]2 (10a) or [(nbd)RhCl]2 (10b) or [(cod)IrCl]2
(10c) (93.3 lmol, 0.5 equiv.) was added to a suspension of
compound 9 (186.6 lmol, 1.0 equiv.) in toluene (15 ml). This
reaction mixture was stirred for 12 hours at room temperature.
Subsequently the insoluble LiCl was filtered off, the solvent
removed in vacuo and the solid washed with pentane (three times,
6 ml each). The resulting yellow solid was dried in vacuo.
Reaction of compound 9 with di(carbonyl)rhodium chloride dimer
(10a), preparation of complex 11
studied here, the metal to C1 separations are rather large (11:
…
˚
˚
˚
Rh · · · C1 3.032 A, 12: Rh · · · C1 3.772 A [3.793 A], 13: Ir C1
˚
3.843 A) and probably outside of a range of any strong direct
A mixture of 9 (118 mg, 186 lmol) and [(CO)2RhCl]2 (10a) (36 mg,
93 lmol) in toluene (15 ml) yielded the yellow, air-stable product
11 (90 mg, 64%). Mp: >200 ◦C (DSC); Found: C, 63.30; H,
4.03; N, 5.13. Calc. for C40H30N3O2P2Rh: C, 64.10; H, 4.03; N,
5.61%; mmax(KBr)/cm−1 3057, 2165, 2061, 1989, 1589, 1483, 1435,
1259, 1175, 1102, 1009, 989, 803, 721 and 690; dH(499.8 MHz;
CD2Cl2; 298 K) 7.71 (m, 8H, o-PhP), 7.48 (m, 4H, p-PhP), 7.33
(m, 8H, m-PhP), 7.12 (m, 4H, o-PhN), 7.02 (m, 4H, m-PhN) and
6.84 (m, 2H, p-PhN); dC(125.7 MHz; CD2Cl2; 298 K) 185.1 (d,
1JRhC = 69.9 Hz, Rh-CO), 152.0 (s, i-PhN), 133.2 (m, o-PhP),
interaction. The frameworks of the newly prepared six-membered
chelate complexes (11 to 13) are distinctively non-planar which
is similar to the j2N,Nꢀ metal complexes of 4.7–10,20 They may
adopt a pronounced boat conformation (as observed for 11) or
favour twist-like conformational arrangements, as was observed
for 12 or 13. We shall see in the future what advantages this
new functionalized chelate ligand might have in applications in
organometallic chemistry and catalysis.
1
3
132.3 (m, p-PhP), 129.2 (pd, JPC + JPC = 95.1 Hz, i-PhP), 128.8
Experimental
2
(m, m-PhP), 128.8 (s, m-PhN), 124.4 (m, o-PhN), 123.1 (t, JPC
=
General
9.3 Hz, C2), 121.5 (s, p-PhN), and 21.6 (t, JPC = 145.6 Hz, C1);
1
d
P{1H}(81.0 MHz; CD2Cl2; 298 K) 29.3 (s, m1/2 = 2.3 Hz). Crystal
All reactions were carried out in an inert atmosphere (ar-
gon) in Schlenk-type glassware or in a glovebox. Solvents
were dried and distilled under argon prior use. Bis(N-
phenyphosphinimino)acetonitrile (6) was prepared using the
known procedure.15 The following instruments were used for the
physical characterization of the compounds. NMR: Bruker AC
200 P-FT (31P: 81.0 MHz), Varian Inova 500 (1H: 499.8 MHz, 13C:
125.7 MHz), Unity Plus 600 (1H: 599.9 MHz, 13C: 150.8 MHz).
Most NMR assignments were supported by additional 2D
experiments. Melting points: DSC 2010 (TA-Instrument). IR:
Varian 3100 FT-IR spectrometer. Elemental analysis: Elementar
Vario El III.
data for C40H30N3O2P2Rh, M = 749.52, monoclinic, space group
P21/c (No. 14), a = 9.8125(2), b = 20.4272(5), c = 17.5318(2)
◦
3
−3
˚
˚
A, b = 102.278(2) , V = 3433.73(12) A , Dc = 1.450 g cm , l =
−1
˚
0.631 mm , Z = 4, k = 0.71073 A, T = 198(2) K, 22757 reflections
−1
˚
collected ( h, k, l), [(sin h)/k] = 0.66 A , 8114 independent
(Rint = 0.056), and 5740 observed reflections [I ≥ 2r(I)], 433 refined
parameters, R = 0.044, wR2 = 0.100. CCDC 676924.†
Reaction of compound 9 with (norbornadiene)rhodium chloride
dimer (10b), preparation of complex 12
A mixture of the lithium salt 9 (118 mg, 186 lmol) and
[(nbd)RhCl]2 (10b) (43 mg, 93 lmol) in toluene (15 ml) formed
the yellow, air-stable product 12 (109 mg, 74%). Mp: >200 ◦C
(DSC); Found: C, 68.11; H, 5.11; N, 5.14. Calc. for C45H38N3P2Rh:
C, 68.79; H, 4.88; N, 5.35%; mmax(KBr)/cm−1 3054, 3003, 2953,
2908, 2851, 2148, 1588, 1482, 1435, 1257, 1233, 1196, 1107, 1010,
Deprotonation reaction of compound 6, formation of 9
A solution of 6 (568 mg, 960 mmol) and lithium diisopropylamide
(97 mg, 960 mmol) in tetrahydrofuran (60 ml) was stirred overnight
at room temperature. The solvent was removed in vacuo and
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986, 803, 745 and 668; dH(599.6 MHz; CD2Cl2; 298 K) 7.93 (m,
8H, o-PhP), 7.55 (m, 4H, p-PhP), 7.47 (m, 8H, m-PhP), 6.76 (m,
4H, m-PhN), 6.63 (m, 2H, p-PhN), 6.16 (m, 4H, o-PhN), 3.44
(m, 2H, 5,8-H), 2.78 (m, 4H, 3,4,6,7-H) and 0.94 (m, 2H, 9-H);
dC(125.7 MHz; CD2Cl2; 298 K) 149.3 (s, i-PhN), 133.8 (m, o-PhP),
Eur. J. Inorg. Chem., 1998, 593–596; D. P. Steinhuebel and S. J. Lippard,
Organometallics, 1999, 18, 109–111; D. P. Steinhuebel and S. J. Lippard,
Organometallics, 1999, 18, 3959–3961; D. P. Steinhuebel and S. J.
Lippard, J. Am. Chem. Soc., 1999, 121, 11762–11772; P. W. Roesky,
J. Organomet. Chem., 2000, 603, 161–166; S. Schulz, M. Nieger, H.
Hupfer and P. W. Roesky, Eur. J. Inorg. Chem., 2000, 1623–1626; F. A.
Hicks and M. Brookhart, Organometallics, 2001, 20, 3217–3219; J. C.
Jenkins and M. Brookhart, Organometallics, 2003, 22, 250–256; D.
Zhang and G.-X. Jin, Organometallics, 2003, 22, 2851–2854; F. A.
Hicks, J. C. Jenkins and M. Brookhart, Organometallics, 2003, 22,
3533–3545; S. Datta, P. W. Roesky and S. Blechert, Organometallics,
2007, 26, 4392–4394.
1
3
132.9 (pd, JPC + JPC = 102.4 Hz, i-PhP), 131.9 (s, p-PhP), 128.5
2
(m, o-PhN), 128.4 (m, m-PhP), 127.7 (s, m-PhN), 124.6 (t, JPC
=
9.4 Hz, C2), 121.5 (s, p-PhN), 61.3 (d, JRhC = 7.0 Hz, C9), 52.5
(d, 1JRhC = 10.6 Hz, C3,4,6,7), 49.0 (d, 2JRhC = 2.8 Hz, C5,8) and
3
1
25.3 (t, JPC = 136.5 Hz, C1); dP{1H}(81.0 MHz; CD2Cl2; 298 K)
3 B.-J. Deelman, P. B. Hitchcock, M. F. Lappert, H.-K. Lee and W.-P.
Leung, J. Organomet. Chem., 1996, 513, 281–285; M. Rahim, N. J.
Taylor, S. Xin and S. Collins, Organometallics, 1998, 17, 1315–1323;
P. H. M. Budzelaar, A. B. van Oort and A. G. Orpen, Eur. J. Inorg.
Chem., 1998, 1485–1494; B. Qian, W. J. Scanlon, IV and M. R. Smith,
III, Organometallics, 1999, 18, 1693–1698; L. W. M. Lee, W. E. Piers,
M. R. J. Elsegood, W. Clegg and M. Parvez, Organometallics, 1999,
18, 2947–2949; X. Jin and B. M. Novak, Macromolecules, 2000, 33,
6205–6207; R. Vollmerhaus, M. Rahim, R. Tomaszewski, S. Xin,
N. J. Taylor and S. Collins, Organometallics, 2000, 19, 2161–2169;
A. Maraval, D. Arquier, A. Igau, Y. Coppel, B. Donnadieu and
J.-P. Majoral, Organometallics, 2001, 20, 1716–1718; P. G. Hayes, W. E.
Piers, L. W. M. Lee, L. K. Knight, M. Parvez, M. R. J. Elsegood and
W. Clegg, Organometallics, 2001, 20, 2533–2544; H. L. Wiencko, E.
Kogut and T. H. Warren, Inorg. Chim. Acta, 2003, 345, 199–208; E. L.
Marshall, V. C. Gibson and H. S. Rzepa, J. Am. Chem. Soc., 2005, 127,
6048–6051; E. Kogut, H. L. Wiencko, L. Zhang, D. E. Cordeau and
T. W. Warren, J. Am. Chem. Soc., 2005, 127, 11248–11249; G. Bai, P.
Wei, A. Das and D. W. Stephan, Organometallics, 2006, 25, 5870–5878;
Y. Yu, W. W. Brennessel and P. L. Holland, Organometallics, 2007, 26,
3217–3226; K. D. Conroy, P. G. Hayes, W. E. Piers and M. Parvez,
Organometallics, 2007, 26, 4464–4470; P. G. Hayes, W. E. Piers and M.
Parvez, Chem.–Eur. J., 2007, 13, 2632–2640; R. C. Jeske, A. M. DiCiccio
and G. W. Coates, J. Am. Chem. Soc., 2007, 129, 11330–11331.
4 See also:E. B. Tjaden, D. C. Swenson and R. F. Jordan, Organometallics,
1995, 14, 371–386; D. G. Black, D. C. Swenson and R. F. Jordan,
Organometallics, 1995, 14, 3539–3550; D. G. Black and R. F. Jordan,
Inorg. Chem., 1997, 36, 103–108; J. Kim, J.-W. Hwang, Y. Kim,
M. H. Lee, Y. Han and Y. Do, J. Organomet. Chem., 2001, 620, 1–
7; R. M. Gauvin, C. Lorber, R. Choukroun, B. Donnadieu and J.
Kress, Eur. J. Inorg. Chem., 2001, 2337–2346; L. Bourget-Merle, M. F.
Lappert and J. R. Severn, Chem. Rev., 2002, 102, 3031–3065; P. G.
Hayes, G. C. Welch, D. J. H. Emslie, C. L. Noack, W. E. Piers and M.
Parvez, Organometallics, 2003, 22, 1577–1579; L. Zhang, M. Brookhart
and P. S. White, Organometallics, 2006, 25, 1868–1874.
29.4 (s, m1/2 = 3.9 Hz). Crystal data for C45H38N3P2Rh·C7H8, M =
877.77, monoclinic, space group P21/c (No. 14), a = 9.9780(1),
◦
˚
b = 20.7312(3), c = 41.3429(7) A, b = 91.050(1) , V = 8550.6(2)
3
−3
−1
˚
˚
A , Dc = 1.364 g cm , l = 4.237 mm , Z = 8, k = 1.54178 A, T =
223(2) K, 78803 reflections collected ( h, k, l), [(sin h)/k] =
−1
˚
0.60 A , 15282 independent (Rint = 0.128), and 10879 observed
reflections [I ≥ 2r(I)], 1018 refined parameters, R = 0.063, wR2 =
0.165. CCDC 676925.
Reaction of compound 9 with (cyclooctadiene)iridium chloride
dimer (10c), preparation of complex 13
Reaction of the lithium salt 9 (120 mg, 186 lmol) and [(cod)IrCl]2
(10c) (63 mg, 93 lmol) in toluene (15 ml) yielded the yellow, air-
stable product 13 (110 mg, 66%). Mp: >200 ◦C (DSC); Found:
C, 61.42; H, 4.92; N, 4.22. Calc. for C46H42IrN3P2: C, 62.01; H,
4.75; N, 4.72%; mmax(KBr)/cm−1 3052, 2911, 2878, 2830, 2154,
1588, 1482, 1436, 1231, 1206, 1108, 1012, 982, 808, 748 and 693;
dH(499.8 MHz; CD2Cl2; 298 K) 7.84 (m, 8H, o-PhP), 7.55 (m, 4H,
p-PhP), 7.44 (m, 8H, m-PhP), 6.75 (m, 4H, m-PhN), 6.68 (m, 2H,
p-PhN), 6.12 (m, 4H, o-PhN), 2.95 (m, 4H, 3,4,7,8-H), 2.00 (m,
4H, 5,6,9,10-H) and 1.24 (m, 4H, 5ꢀ,6ꢀ,9ꢀ,10ꢀ-H); dC(125.7 MHz;
CD2Cl2; 298 K) 148.4 (s, i-PhN), 134.2 (m, o-PhP), 132.9 (pd,
3
1JPC + JPC = 104.8 Hz, i-PhP), 132.2 (m, p-PhP), 129.9 (m, o-
PhN), 128.5 (m, m-PhP), 127.5 (s, m-PhN), 124.1 (t, 2JPC = 7.9 Hz,
C2), 122.5 (m, p-PhN), 60.4 (s, C3,4,7,8), 31.1 (s, C5,6,9,10) and
1
24.6 (t, JPC = 130.7 Hz, C1); dP{1H}(81.0 MHz; CD2Cl2; 298 K)
32.0 (s, m1/2 = 1.9 Hz). Crystal data for C46H42IrN3P2·C7H8, M =
983.10, monoclinic, space group P21/c (No. 14), a = 19.7081(2),
5 T. Sasamori, R. Matsumoto, N. Takeda and N. Tokitoh,
Organometallics, 2007, 26, 3621–3623; J. D. Farwell, P. B. Hitchcock,
M. F. Lappert and A. V. Protchenko, J. Organomet. Chem., 2007,
692, 4953–4961; J. D. Farwell, P. B. Hitchcock and M. F. Lappert,
J. Organomet. Chem., 2007, 692, 5492–5494. See for a comparison: O.
Eisenstein, P. B. Hitchcock, A. V. Khvostov, M. F. Lappert, L. Maron,
L. Perrin and A. V. Protchenko, J. Am. Chem. Soc., 2003, 125, 10790–
10791; M. N. Bochkarev, G. V. Khoroshenkov, H. Schumann and S.
Dechert, J. Am. Chem. Soc., 2003, 125, 2894–2895.
◦
˚
b = 11.3012(1), c = 21.4893(2) A, b = 111.446(1) , V = 4454.82(7)
3
−3
−1
˚
˚
A , Dc = 1.466 g cm , l = 3.108 mm , Z = 4, k = 0.71073 A, T =
223(2) K, 41726 reflections collected ( h, k, l), [(sin h)/k] =
−1
˚
0.66 A , 10575 independent (Rint = 0.053), and 8671 observed
reflections [I ≥ 2r(I)], 533 refined parameters, R = 0.029, wR2 =
0.072. CCDC 676926.
6 T. R. Ward, S. Duclos, B. Therrien and K. Schenk, Organometallics,
1998, 17, 2490–2494; T. Cantat, N. Me´zailles, L. Ricard, Y. Jean and P.
Le Floch, Angew. Chem., 2004, 116, 6542–6545; T. Cantat, N. Me´zailles,
L. Ricard, Y. Jean and P. Le Floch, Angew. Chem., Int. Ed., 2004, 43,
6382–6385; M. C. Aragoni, M. Arca, M. B. Carrea, F. Demartin, F. A.
Devillanova, A. Garau, F. Isaia, V. Lippolis and G. Verani, Eur. J. Inorg.
Acknowledgements
Financial support from the Deutsche Forschungsgemeinschaft
and the Fonds der Chemischen Industrie is gratefully acknowl-
edged.
Chem., 2004, 4660–4668; T. Cantat, M. Demange, N. Mezailles, L.
Ricard, Y. Jean and P. Le Floch, Organometallics, 2005, 24, 4838–
4841; M. Doux, L. Ricard, P. Le Floch and Y. Jean, Organometallics,
2006, 25, 1101–1111; T. Cantat, F. Jaroschik, L. Ricard, P. Le Floch,
F. Nief and N. Me´zailles, Organometallics, 2006, 25, 1329–1332; T.
Cantat, L. Ricard, P. Le Floch and N. Me´zailles, Organometallics,
2006, 25, 4965–4976; T. Cantat, L. Ricard, N. Me´zailles and P. Le
Floch, Organometallics, 2006, 25, 6030–6038; M. C. Aragoni, M. Arca,
M. B. Carrea, F. Demartin, F. A. Devillanova, A. Garau, M. B.
Hursthouse, S. L. Huth, F. Isaia, V. Lippolis, H. R. Ogilvie and G.
Verani, Eur. J. Inorg. Chem., 2006, 200–206; J. S. Ritch, T. Chivers,
D. J. Eisler and H. M. Tuononen, Chem.–Eur. J., 2007, 13, 4643–
4653.
´
Notes and references
1 D. Gibson, Coord. Chem. Rev., 1969, 4, 225–240; U. Casellato and P. A.
Vigato, Coord. Chem. Rev., 1977, 23, 31–117; U. Casellato and P. A.
Vigato, Chem. Soc. Rev., 1979, 8, 199–220.
2 H. V. R. Dias, W. Jin and Z. Wang, Inorg. Chem., 1996, 35, 6074–
6079; M. J. Scott and S. J. Lippard, Inorg. Chim. Acta, 1997, 263,
287–299; P. W. Roesky, Chem. Ber., 1997, 130, 859–862; M. J. Scott
and S. J. Lippard, Organometallics, 1998, 17, 1769–1773; P. W. Roesky,
This journal is
The Royal Society of Chemistry 2008
Dalton Trans., 2008, 3339–3344 | 3343
©

View Article Online
7 Monoanionic derivatives: A. Kasani, R. McDonald and R. G. Cavell,
Organometallics, 1999, 18, 3775–3777; S. Al-Benna, M. J. Sarsfield, M.
Thornton-Pett, D. L. Ormsby, P. J. Maddox, P. Bre´s and M. Bochmann,
J. Chem. Soc., Dalton Trans., 2000, 4247–4257; M. S. Hill and P. B.
Hitchcock, J. Chem. Soc., Dalton Trans., 2002, 4694–4702; M. S. Hill
and P. B. Hitchcock, Chem. Commun., 2003, 1758–1759; M. S. Hill, P. B.
Hitchcock and S. M. A. Karagouni, J. Organomet. Chem., 2004, 689,
722–730; M. S. Hill and P. B. Hitchcock, J. Organomet. Chem., 2004,
689, 3163–3167; Y. Smurnyy, C. Bibal, M. Pinka and K. G. Caulton,
Organometallics, 2005, 24, 3849–3855; M. Demange, L. Boubekeur,
A. Auffrant, N. Me´zailles, L. Ricard, X. Le Goff and P. Le Floch,
New J. Chem., 2006, 30, 1745–1754; L. Orzechowski, G. Jansen and
S. Harder, J. Am. Chem. Soc., 2006, 128, 14676–14684; S. A. Ahmed,
M. S. Hill and P. B. Hitchcock, Organometallics, 2006, 25, 394–402; M.
Wiecko, P. W. Roesky, V. V. Burlakov and A. Spannenberg, Eur. J. Inorg.
Chem., 2007, 876–881; M. Raststa¨tter, A. Zulys and P. W. Roesky,
Chem.–Eur. J., 2007, 13, 3606–3616.
Dalton Trans., 1976, 439–446; R. J. Puddephatt, Chem. Soc. Rev., 1983,
12, 99–127; D. M. A. Minahan and W. E. Hill, Coord. Chem. Rev., 1984,
55, 31–54; C.-L. Lee, Y.-P. Yang, S. J. Rettig, B. R. James, D. A. Nelson
and M. A. Lilga, Organometallics, 1986, 5, 2220–2228; H. Schmidbaur,
G. Reber, A. Schier, F. E. Wagner and G. Mu¨ller, Inorg. Chim. Acta,
1988, 147, 143–150; D. L. Oliver and G. K. Anderson, Polyhedron,
1992, 11, 2415–2420; L. Luo, N. Zhu, N.-J. Zhu, E. D. Stevens and
S. P. Nolan, Organometallics, 1994, 13, 669–675; C. Li, M. E. Cucullu,
R. A. McIntyre, E. D. Stevens and S. P. Nolan, Organometallics, 1994,
13, 3621–3627; S. M. Reid, J. T. Mague and M. J. Fink, J. Am. Chem.
Soc., 2001, 123, 4081–4082; S. J. Dossett, A. Gillon, A. G. Orpen, J. S.
Fleming, P. G. Pringle, D. F. Wass and M. D. Jones, Chem. Commun.,
2001, 699–700; M. I. Bruce, B. G. Ellis, P. J. Low, B. W. Skelton and
A. H. White, Organometallics, 2003, 22, 3184–3198.
12 For an example of a CN-substituted acac system see: D. Wisbey, D.
Feng, M. T. Bremer, C. N. Borca, A. N. Caruso, C. M. Silvernail, J.
Belot, E. Vescovo, L. Ranno and P. A. Dowben, J. Am. Chem. Soc.,
2007, 129, 6249–6254.
13 L. Braun, P. Liptau, G. Kehr, J. Ugolotti, R. Fro¨hlich and G. Erker,
Dalton Trans., 2007, 1409–1415.
14 L. Braun, G. Kehr, T. Blo¨mker, R. Fro¨hlich and G. Erker, Eur. J. Inorg.
Chem., 2007, 3083–3090.
15 L. Braun, G. Kehr, R. Fro¨hlich and G. Erker, Inorg. Chim. Acta, 2008,
361, 1668–1675.
16 H. Staudinger and J. Meyer, Helv. Chim. Acta, 1919, 2, 635–646.
17 31P-NMR-Spektroskopie in NMR-Spektroskopie von Nichtmetallen, ed.
S. Berger, S. Braun and H.-O. Kalinowski, Georg Thieme Verlag
Stuttgart, New York, 1993; L. D. Quin and J. G. Verkade, in
Methods in Stereochemical Analysis, Phosphorus-31 NMR Spectral
Properties in Compound Characterization and Structural Analysis, ed.
A. P. Marchand, VCH, New York, Weinheim, Cambridge, 1994.
18 J. G. Verkade and L. D. Quin, in Methods in Stereochemical Analysis,
Phorphorus-31 NMR Spectroscopy in Stereochemical Analysis, ed.
A. P. Marchand, VCH, Deerfield Beach, Weinheim, 1987; W. C. Kaska,
K. A. O. Starzewski and D. A. Dixon, in Ylides and Imines of Phospho-
rus, ed. A. W. Johnson, John Wiley & Sons, New York, Chichester,
Brisbane, Toronto, Singapore, 1993; A Guide to Organophosphorus
Chemistry, ed. L. D. Quin, John Wiley & Sons, New York, Chichester,
Weinheim, Brisbane, Singapore, Toronto, 2000.
19 F. Bonati and G. Wilkinson, J. Chem. Soc., 1964, 3156–3160; F. Bonati
and R. Ugo, J. Organomet. Chem., 1967, 7, 167–180; D. M. Adams and
W. R. Trumble, J. Chem. Soc., Dalton Trans., 1974, 690–692.
20 P. Imhoff and C. J. Elsevier, J. Organomet. Chem., 1989, 361, C61–C65;
P. Imhoff, R. van Asselt, C. J. Elsevier, M. C. Zoutberg and C. H. Stam,
Inorg. Chim. Acta, 1991, 184, 73–87; P. Imhoff, S. C. A. Nefkens, C. J.
Elsevier, K. Goubitz and C. H. Stam, Organometallics, 1991, 10, 1421–
1431; P. Imhoff, R. van Asselt, J. M. Ernsting, K. Vrieze, C. J. Elsevier,
W. J. J. Smeets, A. L. Spek and A. P. M. Kentgens, Organometallics,
1993, 12, 1523–1536.
8 Dianionic derivatives: R. G. Cavell, R. P. Kamalesh, Babu, A. Kasani
and R. McDonald, J. Am. Chem. Soc., 1999, 121, 5805–5806; R. P.
Kamalesh, Babu, R. McDonald, S. A. Decker, M. Klobukowski and
R. G. Cavell, Organometallics, 1999, 18, 4226–4229; R. P. Kamalesh,
Babu, R. McDonald and R. G. Cavell, Chem. Commun., 2000,
481–482; R. P. Kamalesh, Babu, R. McDonald and R. G. Cavell,
Organometallics, 2000, 19, 3462–3465; K. Aparna, M. Ferguson and
R. G. Cavell, J. Am. Chem. Soc., 2000, 122, 726–727; V. Cadierno,
´
J. D´ıez, J. Garc´ıa-Alvarez and J. Gimeno, Organometallics, 2005, 24,
2801–2810; N. D. Jones and R. G. Cavell, J. Organomet. Chem., 2005,
690, 5485–5496; L. Orzechowski and S. Harder, Organometallics, 2007,
26, 2144–2148; L. Orzechowski and S. Harder, Organometallics, 2007,
26, 5501–5506.
9 Neutral derivatives: M. J. Sarsfield, M. Thornton-Pett and M.
Bochmann, J. Chem. Soc., Dalton Trans., 1999, 3329–3330; K. Krei-
scher, J. Kipke and M. Bauerfeind, Z. Anorg. Allg. Chem., 2001, 627,
1023–1028; J. Sundermeyer, P. Wei and D. W. Stephan, Organometallics,
´
2003, 22, 601–604; V. Cadierno, J. D´ıez, J. Garc´ıa-Alvarez and J.
Gimeno, Organometallics, 2004, 23, 2421–2433; C. Zhang, W.-H. Sun
and Z.-X. Wang, Eur. J. Inorg. Chem., 2006, 4895–4902.
´
10 See also: V. Cadierno, P. Crochet, J. Garc´ıa-Alvarez, S. E. Garc´ıa-
Garrido and J. Gimeno, J. Organomet. Chem., 2002, 663, 32–39; L. P.
Spencer, R. Altwer, P. Wei, L. Gelmini, J. Gauld and D. W. Stephan,
Organometallics, 2003, 22, 3841–3854; G. C. Welch, W. E. Piers, M.
Parvez and R. McDonald, Organometallics, 2004, 23, 1811–1818; J. D.
Masuda, D. M. Walsh, P. Wei and D. W. Stephan, Organometallics,
2004, 23, 1819–1824; M. T. Gamer and P. W. Roesky, Organometallics,
2004, 23, 5540–5544; A. Lofu`, P. Mastrorilli, C. F. Nobile, G. P.
Suranna, P. Frediani and J. Iggo, Eur. J. Inorg. Chem., 2006, 2268–
2276.
11 W. L. Steffen and G. J. Palenik, Inorg. Chem., 1976, 15, 2432–2439;
T. G. Appleton, M. A. Bennett and I. B. Tomkins, J. Chem. Soc.,
3344 | Dalton Trans., 2008, 3339–3344
This journal is
The Royal Society of Chemistry 2008
©