Preparation of phosphinoferrocene carboxamides from isocyanates. Synthesis and structural characterisation of palladium(II) and platinum(II) complexes with 1′-(diphenylphosphino)-1-(N-phenylcarbamoyl)ferrocene

Article abstract of DOI:10.1016/j.jorganchem.2010.07.013

The reaction of in situ generated 1′-(diphenylphosphino)-1- lithioferrocene with isocyanates RNCO affords the respective phosphino-carboxamides Ph₂PfcCONHR (fc = ferrocene-1,1′-diyl, R = cyclohexyl (2), and Ph (3)) in moderate yields. The coordination behaviour of 3 chosen as a representative was studied in palladium(II) and platinum(II) complexes. Depending on the metal precursor and the reaction conditions, the following compounds featuring this ligand as a P-monodentate or an O,P-chelating donor were isolated and characterised by spectroscopic methods (IR, multinuclear NMR and electrospray ionisation MS): trans-[PdCl ₂(3-κP)₂] (5), trans-[PtCl₂(3-κP) ₂] (6), cis-[PtCl₂(3-κP)₂] (7), [SP-4-4]-[(L^NC)PdCl(3-κP)] (8; L^NC = 2-[(dimethylamino-κN)methyl]phenyl-κC¹), and [SP-4-3]-[(L^NC)PdCl(3-κ²O,P)]SbF₆ (9). Besides, the crystal structures of a phosphine oxide resulting by oxidation of 2, viz Ph₂P(O)fcCONHCy (4), and of complexes 5·2Et ₂O and 9 have been determined by single-crystal X-ray diffraction analysis.

Full text of DOI:10.1016/j.jorganchem.2010.07.013

Journal of Organometallic Chemistry 695 (2010) 2423e2431
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Preparation of phosphinoferrocene carboxamides from isocyanates. Synthesis
and structural characterisation of palladium(II) and platinum(II) complexes
with 10-(diphenylphosphino)-1-(N-phenylcarbamoyl)ferrocene
ꢀ
*
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
Petr Stepnicka , Hana Solarová, Martin Lamac, Ivana Císarová
Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague; Hlavova 2030, 12840 Prague, Czech Republic
a r t i c l e i n f o
a b s t r a c t
The reaction of in situ generated 10-(diphenylphosphino)-1-lithioferrocene with isocyanates RNCO
affords the respective phosphino-carboxamides Ph2PfcCONHR (fc ¼ ferrocene-1,10-diyl, R ¼ cyclohexyl
(2), and Ph (3)) in moderate yields. The coordination behaviour of 3 chosen as a representative was
studied in palladium(II) and platinum(II) complexes. Depending on the metal precursor and the reaction
conditions, the following compounds featuring this ligand as a P-monodentate or an O,P-chelating donor
were isolated and characterised by spectroscopic methods (IR, multinuclear NMR and electrospray
Article history:
Received 21 April 2010
Received in revised form
13 July 2010
Accepted 15 July 2010
Available online 22 July 2010
ionisation MS): trans-[PdCl2(3-
k
P)2] (5), trans-[PtCl2(3-
k
P)2] (6), cis-[PtCl2(3-
k
k
P)2] (7), [SP-4-4]-[(LNC)PdCl
Keywords:
Ferrocene
Carboxamides
Isocyanates
Palladium
(3-k
P)] (8; LNC ¼ 2-[(dimethylamino-
k
N)methyl]phenyl- k
C1), and [SP-4-3]-[(LNC)PdCl(3-
2O,P)]SbF6 (9).
Besides, the crystal structures of a phosphine oxide resulting by oxidation of 2, viz Ph2P(O)fcCONHCy (4),
and of complexes 5$2Et2O and 9 have been determined by single-crystal X-ray diffraction analysis.
Ó 2010 Elsevier B.V. All rights reserved.
Platinum
Structure elucidation
1. Introduction
as early as in 1901 [6], has found only surprisingly little use in
ferrocene chemistry. The only example we are aware of is the
Ferrocene-based phosphinocarboxamide donors were shown to
be versatile ligands, finding applications in coordination chemistry
and catalysis [1,2]. Most typically, these compounds are prepared via
amide coupling of the respective phosphinocarboxylic acids and
amines mediated by carbodiimide reagents [3] or, alternatively, by
reactions of activated carboxylic derivatives (e.g., pentafluorophenyl
esters) with amines [1i,4].
While looking for an alternative preparative route to ferrocene
phosphino-carboxamides, isocyanates emerged as possible
synthetic precursors. Indeed, the direct carbamoylation of ferrocene
with isocyanates in the presence of AlCl3 was reported already in
1957 [5]. However, this reaction proceeds under the usual Frie-
deleCrafts conditions, which could result in oxidation of the phos-
phine moiety and may thus lead to a lengthening of the synthesis
route by the necessary protection/deprotection steps. A more
promising route thus appeared to be the reaction of isocyanates with
organometals as the nucleophiles. This reaction, although discovered
synthesis of carboxamides from ortho-lithiated aminoferrocenes, [Fe
{h
5-C5H3((CH2)nNMe2)(CONHPh)-1,2}(
h
5-C5H5)] (n ¼ 1 and 2) [7].
A related approach, not making use of pre-formed metallocenes, was
more recently utilised in the preparation of amide-substituted
metallocenes via metathesis between metal halides and Li[C5H4C(O)
NHR] salts, the latter being generated in situ from lithium cyclo-
pentadienide and the respective isocyanate (R ¼ n- and t-Bu, cyclo-
hexyl, Ph, 3-pyridyl, and 2-tetrahydropyranyl) [8].
The relatively mild reaction conditions, generally good yields
and simplicity of the direct reaction of the mentioned lith-
ioferrocenes with isocyanates led us to extend this approach to
10-(diphenylphosphino)-1-lithioferrocene. This reactive compound
is readily prepared in situ via lithiation of stable 10-(diphenyl-
phosphino)-1-bromoferrocene and has already found manifold use
in the preparation of 10-functionalised ferrocene phosphines [9]. In
this contribution, we demonstrate the validity of the ‘isocyanate
approach’ outlined above, reporting on the preparation of two new
ferrocene phosphine-carboxamides, Ph2PfcC(O)NHR (fc ¼ ferro-
cene-1,10-diyl; R ¼ cyclohexyl (2), and Ph (3)). We also describe the
synthesis and structural characterisation of some platinum(II) and
palladium(II) complexes featuring compound 3 as a P-monodentate
or an O,P-chelating donor.
* Corresponding author. Fax: þ420 221 951 253.
ꢀ
ꢀ
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E-mail address: stepnic@natur.cuni.cz (P. Stepnicka).
0022-328X/$ e see front matter Ó 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2010.07.013

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2. Results and discussion
2.1. Preparation and characterisation of phosphinoferrocene
carboxamides
10-(Diphenylphosphino)-1-lithioferrocene, generated conve-
niently in situ by lithiation of 1-bromo-10-(diphenylphosphino)
ferrocene (1) with n-butyllithium at low temperatures, reacts with
cyclohexyl- or phenylisocyanate to give the corresponding phos-
phine-amides 2 and 3 (Scheme 1). Following the aqueous workup,
the amides are isolated by column chromatography as analytically
pure orange solids in moderate yields of 69% and 32%, respectively. It
appears likely that the reaction is impeded by the solubility of the
isocyanates in tetrahydrofuran at low temperatures. The reaction
with the less soluble phenylisocyanate not only gives a lower yield
of the ‘coupling’ product but also affords a relatively larger amount
of (diphenylphoshino)ferrocene, resulting from protonolysis of the
lithiated intermediate. Fortunately, however, this side-product is
readily separated by column chromatography as a low-polar
component. Another, more polar side-product, detected in the
reaction leading to N-cyclohexyl amide 2, was found to be the cor-
responding phosphine oxide 4 resulting in tiny amounts by acci-
dental oxidation.
Compounds 2e4 were characterised by elemental analysis and
by spectroscopic methods (multinuclear NMR, IR and mass spectra).
In the NMR spectra, amides 2 and 3 display a set of characteristic
virtual multiplets attributable to phosphorus-substituted ferro-
cene-1,10-diyl unit and its PPh2 and amide substituents. Resonances
due to the amide protons (NH) of 2 and 3 are seen as a singlet (dH
Fig. 1. A view of the molecular structure of 4 showing the atom labelling scheme and
displacement ellipsoids at 30% probability level. The intramolecular NeH/O hydrogen
bond is indicated with a dotted line.
ꢁ
which can be tentatively formulated as [FcPPh2O]þ (m/z 386),
[FcPPh2O ꢀ C5H5]þ (m/z 321; intense signals) and [Ph2PO]þ (m/z
3
7.75) or CH-coupled doublet (dH 5.78, JHH ¼ 8.1 Hz), respectively.
ꢁ
ꢁ
201), suggests that the decomposition of 2þ and 3þ involves
a transfer of oxygen atom from the amide group to phosphorus as
previously observed for Hdpf and the related compounds [13].
13C NMR spectra of 2e4 support the formulation, showing signals of
the 10-(diphenylphosphino)ferrocene-1-yl moiety and the amide
substituents. The resonances due to the amide C]O occur at dC ca.
168.5, which is similar to other Hdpf-based amides (Hdpf ¼ 10-
(diphenylphosphino)ferrocene-1-carboxylic acid) [1a,b,eej] and
considerably upfield vs. free Hdpf [10].
2.2. The crystal structure of 4
The 31P NMR signals of 2 and 3 are found at positions similar to
Hdpf (dP ꢀ17.6 [10]). On the other hand, the oxidation of the
phosphine groups in 4 is clearly manifested by a shift of the 31P
NMR resonance to lower fields (cf. dP þ32.9 for HdpfO [10]) and
further by shifts of the 1H and 31C signals and an increase in the JPC
coupling constants [11]. The presence of secondary amide groups is
In addition to spectroscopic characterisation, the crystal struc-
ture of 4 was determined by single-crystal X-ray diffraction anal-
ysis. A view of the molecular structure is shown in Fig. 1. Selected
geometric data are given in Table 1.
Compound 4 crystallises with the symmetry of the monoclinic
space group P21/n and one molecule in the asymmetric unit.
Because the amide NH proton as the only conventional hydrogen
bonding acceptor is saturated by intramolecular P]O/HeN
hydrogen bond, the individual molecules in the crystal associate
only via soft interactions. These include mainly intermolecular
uniformly manifested via a broad nNH band at 3250e3300 cmꢀ1
,
and by amide I/II bands at ca. 1640/1530 cmꢀ1 in the IR spectra.
Electrospray ionisation (ESI) mass spectra of 2 and 3 display
dominant pseudomolecular ions ([M þ Na]þ or [M ꢀ H]ꢀ), while the
ꢁ
‘true’ molecular ions (Mþ ) are seen in electron impact (EI) mass
spectra. The EI mass spectra of 2 and 3 further show ions resulting by
simple fragmentation [M ꢀ R]þ (m/z 412, R ¼ Cy or Ph), [M ꢀ NHR]þ
(m/z 397 [12]), and [M ꢀ C5H4CONHR]þ (m/z 305), and fragments
typical for the EI-induced decomposition of the (diphenylphos-
phino)ferrocene unit (m/z 226/227, 197, 170/171, 141) [13] and the
PPh2 group (m/z 183, [Ph2P ꢀ 2H]þ). The presence of fragment ions,
Table 1
a
Selected distances and angles for 4 (in A and ꢂ).
ꢁ
FeeCg1
FeeCg2
C1eC11
C11eO1
C11eN
NeC24
PeO2
PeC6
PeC12
PeC18
1.649(1)
1.642(1)
1.488(3)
1.234(3)
1.347(3)
1.459(3)
1.490(2)
1.786(2)
1.806(2)
1.807(2)
:Cp1,Cp2
1.0(1)
77
24.6(3)
123.1(2)
121.7(2)
172.7(2)
112.48(9)e113.59(9)
104.85(9)e105.89(9)
0.0(3)
sb
jc
O1eC11eN
C11eNeC24
O1eC11eNeC24
O2ePeCd
CePeCe
PPh
PPh
2
2
1. LiBu
4f
Qf
Fe
Fe
0.567(3)
2. RNCO
NHR
a
Definition of the ring planes: Cp1 ¼ C(1e5), Cp2 ¼ C(6e10); Cg1 and Cg2 are the
Br
C
respective ring centroids.
b
1
O
Torsion angle C1eCg1eCg2eC6.
Dihedral angle of the Cp1 and {C11,O1,N} planes.
The range of O2ePeC(6,12,18) angles.
The range of C6ePeC(12,18) and C12ePeC18 angles.
c
2 (R = Cy)
3 (R = Ph)
d
e
f
Ring puckering parameters for the cyclohexyl group C(24e29) (Q ¼ total
Scheme 1. Preparation of amidophosphine ligands 2 and 3.
puckering amplitude; ideal chair requires
4
¼ 0ꢂ).

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P. Stepnicka et al. / Journal of Organometallic Chemistry 695 (2010) 2423e2431
2425
CeH/O hydrogen bonds involving the aromatic CH groups and P]
PhHN
O or C]O oxygens (Table 2), and supportive CeH/p-ring inter-
C
i
actions (C9eH9/Ph1i: C9/Cg(Ph1 ) ¼ 3.706(2) A, C9eH9/Cg
ꢁ
O
Cl
Ph
ii
Ph
(Ph1i) ¼ 160ꢂ;
C14eH14/Ph2ii:
C14/Cg(Ph2 ) ¼ 3.525(2) A,
ꢁ
Fe
P
C14eH14/Cg(Ph2ii) ¼ 169ꢂ; Ph1 ¼ C(12e18), Ph2 ¼ C(18e23), Cg
denotes the ring centroids; i ¼ 1/2 ꢀ x,1/2 þ y,1/2 ꢀ z, ii ¼ 1 ꢀ x, ꢀy,
1 ꢀ z).
3
M
[PdCl (cod)] or K [PtCl ]
2
2
4
P
- cod
or 2KCl
Cl
O
Ph
Fe
Ph
The molecular geometry of the phosphine oxide is unexceptional.
The parameters of the amide moiety are similar to other Hdpf-based
amides [1b,d,f,hej] while the P]O bond lengthꢂis identical to that
C
NHPh
ꢁ
observed for crystalline HdpfO (1.487(2) A at 23 C [10]). The ferro-
5 (M = Pd)
6 (M = Pt)
cene cyclopentadienyls in 4 are tilted negligibly (tilt angle ca.1ꢂ) and
assume a conformation near to synclinal eclipsed (ideal value:
s
¼ 72ꢂ). Such conformation and the observed rotation of the amide
moiety along the pivotal C1eC11 bond (see
j angle in Table 1)
PhHN
apparently facilitate the formation of the intramolecular NeH/O]
P hydrogen bond. The pendant cyclohexyl group adopts a chair
conformation (see the ring puckering parameters [14] inTable 2) and
binds to the amide nitrogen atom in an equatorial position.
C
O
Fe
Ph
Ph
Ph
Ph
Pt
3
P
[PtCl (cod)]
2
P
2.3. Preparation of complexes from ligand 3
- cod
Cl
Cl
O
Fe
The reactions of amidophosphine 3 (two molar equivalents)
with [PdCl2(cod)] (cod ¼ h2
:h
2-cycloocta-1,5-diene) or K2[PtCl4]
gave rise to the expected trans-bis(phosphine) complexes, trans-
C
NHPh
[MCl2(3-
with [PtCl2(cod)] afforded the isomeric compound, cis-[PtCl2(3-
P)2] (7). The complexes were isolated as air stable solids with
k
P)2] (5, M ¼ Pd; 6, M ¼ Pt; Scheme 2). A similar reaction
7
k
Scheme 2. Preparation of bis(phosphine) palladium(II) and platinum(II) complexes.
a strong tendency to hold the reaction solvents. They were char-
acterised by 1H and 31P NMR spectra, IR and ESI mass spectra, and
by elemental analysis.
A reaction between stoichiometric amounts of 3 and dimer [(LNC
)
ESI mass spectra corroborate the formulation of 5e7 by
showing ions due to [M þ Na]þ (for 5 and 6), [M ꢀ Cl]þ (for 5 and
7), or deprotonated molecular ions [M ꢀ H]ꢀ (for 6 and 7). The 1H
NMR spectra of 5e7 display one set of resonances due to coordi-
nated 3, thereby suggesting equivalency of the metal-bound
ligands. Signals in the 31P NMR spectra of the complexes are found
shifted to lower fields as compared to free 3. For the platinum
complexes, the 31P NMR resonances are flanked with 195Pt satel-
PdCl]2 (LNC ¼ [2-(dimethylamino-
kN)methyl]phenyl-k
C1) produced
the bridge-cleavage product featuring donor 3 as a simple phos-
phine, [(LNC)PdCl(3-
k
P)] (8; Scheme 3). Upon removal of the chlo-
8 with silver(I) hexafluoroantimonate, the
ferrocene ligand takes up the liberated coordination site while 8 is
ride ligand from
1
Ph
Ph
lites with characteristic coupling constants (6: JPtP ¼ 2604 Hz; 7:
1JPtP ¼ 3786 Hz) [15]. The 31P NMR parameters of 5e7 compare
N
P
Pd
well with those of the analogous complexes [MCl2(Hdpf-
k
P)2] [16]
N
3
and thus indicate P-monodentate coordination of
3
for all
Cl
O
Fe
Pd
Cl
complexes. Indeed, this is in line with the IR spectra confirming
the amide group to remain uncoordinated.
C
2
NHPh
Table 2
8
Hydrogen bond parameters for 4, 5$2Et2O and 9 (in A and ꢂ).
ꢁ
DeH/A
D/A
Angle at H
AgSbF
- AgCl
6
Compound 4
NeH/O2
3.012(2)
3.462(3)
3.396(3)
171
162
157
C8eH8/O2i
C16eH16/O1ii
Ph
SbF
Ph
6
Compound 5$2Et2O
NeH1N/Oiii
P
3.129(4)
3.401(5)
3.281(6)
166
156
136
C2eH2/Oiii
Pd
O
C27eH27/Oiii
Fe
N
Compound 9
N1eH1N/F6iv
C2eH2/F6iv
3.062(4)
3.237(5)
3.156(6)
3.449(6)
162
158
139
159
C
C28eH28/F3vi
C37eH37A/F2
NHPh
9
D ¼ donor, A ¼ acceptor. Symmetry operations: i ꢀ1/2 þ x, 1/2 ꢀ y, ꢀ1/2 þ z; ii ¼ 1/
2 ꢀ x, ꢀ1/2 þ y, 1/2 ꢀ z; iii ¼ x, 1/2 ꢀ y, 1/2 þ z; iv ¼ x, 1/2 ꢀ y, 1/2 þ z; vi ¼ ꢀx, 1 ꢀ y,
1 ꢀ z.
Scheme 3. Preparation of palladium(II) complexes with auxiliary 2-[(dimethylamino)
methyl]phenyl ligand.

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P. Stepnicka et al. / Journal of Organometallic Chemistry 695 (2010) 2423e2431
Fig. 2. A view of the complex molecule in the structure of 5$2Et2O showing atomic labels and displacement ellipsoids at 30% probability level.
smoothly converted into a cationic bis-chelate complex [(LNC)PdCl
(3-
2O,P)] (9).
The 1H NMR spectra of 8 and 9 combine characteristic signals
phenyl H29 that are both adjacent to the amide moiety and directed
towards the same carbonyl oxygen (Fig. 3a). Since each complex
molecule has two amide units and the H-bond contacts involve
ligands from different complex molecules (not related by simple
translation), the hydrogen bond interactions result in the formation
of infinite, sheet-like assemblies oriented parallel to the crystallo-
graphic bc plane (Fig. 3b).
k
due to ligand 3 and the Pd-bound C6H4CH2NMe2 moiety. The
P-coordination of the amidophosphine ligand is manifested by the
shift of the 31P NMR resonance to lower fields (coordination shifts;
8: DP ¼ 49.6; 9: DP ¼ 47.7 ppm) and the coupling of the NCH2 and
4
NMe2 protons with phosphorus (the JPH constants) [17] suggest
A view of the molecular structure of the cation in the structure
of complex 9 is shown in Fig. 4. Selected geometric data are given in
Table 4. The overall geometry of the cation compares well with that
observed for an analogous complex featuring a related functional
amide as an O,P-chelating donor, [(LNC)Pd(Ph2PfcCONHCH2CO2Me)]
ClO4 [1h]. Similarly to this reference compound, the coordination
environment of the palladium atom is angularly distorted owing to
unlike steric demands of the chelating ligands: The N2ePdeC30
angle within the small metallacycle is expectedly the most acute,
while the OePdeP angle associated with the chelating ferrocene
ligand is the most opened. The atoms constituting the coordination
trans-PeN relationship in both cases. Positive-ion ESI mass spectra
of 8 and 9 are dominated by the ions [(LNC)Pd(3)]þ at m/z 729 (i.e.,
[M ꢀ Cl]þ for 8). On the other hand, the spectra recorded in negative
ion mode either confirm the formulation (ions due to [M ꢀ H]ꢀ and
[L ꢀ H]ꢀ are seen for 8) or indicate the presence of the counter ion
(9: m/z 235/237). The presence of SbFꢀ6 is further reflected in IR
spectra showing a strong and structured band at ca. 660 cmꢀ1 [18].
Besides, the IR spectra clearly indicate the involvement of the
amide C]O group in coordination. Whereas complex 8 featuring P-
monodentate 3 shows amide I band (largely nC]O) at 1666 cmꢀ1
,
the cationic bis-chelate 9 has the same band shifted by 55 cmꢀ1 to
plane (Pd,P,O,N2,C30) are coplanar within ca. 0.15 A. The {(LNC)Pd}
ꢁ
lower energies (1611 cmꢀ1).
ring assumes an envelope conformation with N2 projecting by ca.
ꢁ
0.3 A from the plane of the remaining atoms.
The ferrocene unit in 9 shows a tilt of ca. 5ꢂ and an insignificant
variation in the FeeCg distances (the individual FeeC distances
2.4. The crystal structures of 5$2Et2O and 9
A careful recrystallisation of 5 from chloroform/diethyl ether
afforded the crystalline solvate 5$2Et2O [19]. The solvent molecules
in the structure of 5$2Et2O were found to be severely disordered in
structural voids defined by the bulky complex molecules and,
therefore, their contribution was numerically subtracted from the
overall scattering (see Experimental). A view of the complex
molecule is presented in Fig. 2. Pertinent geometric parameters are
summarised in Table 3.
The complex crystallises with the symmetry of the monoclic
space group P21/c having its palladium atom located on the crys-
tallographic inversion centre. As a result, the coordination sphere is
ideally planar though with the interligand angles differing slightly
from the ideal 90ꢂ. The Pd-donor distances are similar to those
Table 3
a
Selected distances and angles for 5$2Et2O (in A and ꢂ).
ꢁ
PdeCl
PdeP
2.284(1)
2.3310(8)
1.647(2)
1.652(2)
1.483(6)
1.227(4)
1.357(5)
1.409(5)
1.797(3)
1.819(4)
1.829(3)
ClePdePb
:PdL4,Cp2
:Cp1,Cp2
sc
87.97(4)
35.2(2)
1.9(2)
145
7.5(5)
123.4(4)
128.1(3)
32.9(3)
8.5(7)
107.5(1)e122.0(1)
100.0(2)e105.5(2)
FeeCg1
FeeCg2
C1eC11
C11eO
C11eN
NeC24
PeC6
jd
OeC11eN
C11eNeC24
:Cp1,PhN
OeC11eNeC24
PdePeCe
CePeCf
PeC12
PeC18
a
Definition of the ring planes: Cp1 ¼ C(1e5), Cp2 ¼ C(6e10), PdL4 ¼
{Pd,Cl,Cl0,P,P0}, PhN ¼ C(24e29). The primed atoms are generated by the crystallo-
graphic inversion operation. Cg1 and Cg2 denote centroids of the rings Cp1 and Cp2,
respectively.
reported for trans-[PdCl2(Hdpf-kP)2]$2CH3CO2H [16]. The uncoor-
dinated amide moiety is tilted with respect to its parent cyclo-
pentadienyl ring (see
from the coordinated metal (
to less sterically encumbered areas and allows them to form
NeH/O]C hydrogen bonds with the proximal ligand moieties
(Table 2). Interestingly, the NeH/O interaction is supported via
cooperative soft CeH/O contacts from the ferrocene H2 and the
j angle in Table 3) and, mainly, rotated away
b
The ClePdeP and ClePdeP0 angles sum to exactly 180ꢂ due to imposed
s
¼ 145ꢂ). This brings the amide units
symmetry.
c
Torsion angle C1eCg1eCg2eC6.
Dihedral angle of the Cp1 and {C11,O,N} planes.
The range of PdePeC(6,12,18) angles.
The range of C6ePeC(12,18) and C12ePeC18 angles.
d
e
f

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P. Stepnicka et al. / Journal of Organometallic Chemistry 695 (2010) 2423e2431
2427
Fig. 3. (a) A view of the basic hydrogen-bonded unit in the structure of 5$2Et2O showing the cooperative NeH/O and CeH/O hydrogen bonds as dashed lines. (b) Section of the
hydrogen-bonded array in the same crystal structure. For clarity, only the pivotal phenyl ring carbons and relevant hydrogen atoms are shown and the supportive CeH/O contacts
are omitted.
(1)ꢂ). In the solid state, however, the anions interact with the
proximal complex cations via NeH/F and CeH/F hydrogen bonds
(Fig. 5 and Table 2).
ꢁ
range 2.001(4)e2.074(4) A). More importantly, the ferrocene
substituents are rotated to an intermediate conformation between
synclinal staggered (
s
¼ 36ꢂ) and synclinal eclipsed (
s
¼ 72ꢂ), which
enables their simultaneous coordination. Likewise, the amide
moiety (C11,N1,O) is rotated along its pivotal C1eC11 bond (see
j
Table 4
angle in Table 4) and, simultaneously, bent towards the palladium
with the dihedral angle of the C1eC11 bond and the Cp1 plane
being 9.6(3)ꢂ (N.B. The dihedral angle subtended by the PeC6 bond
and the Cp2 plane is only 1.2(2)ꢂ). The coordinated C]O bond is by
a
Selected distances and angles for 9 (in A and ꢂ).
ꢁ
PdeP
PdeO
2.273(1)
2.156(3)
2.143(3)
2.011(4)
1.640(2)
1.627(2)
1.248(5)
PePdeO
PePdeC30
N2ePdeO
N2ePdeC30
:PdL4,Cp2
:Cp1,Cp2
sb
99.02(8)
92.9(1)
86.4(1)
82.6(1)
53.5(2)
4.7(2)
62
121.0(4)
19.0(4)
113.9(1)e118.8(1)
98.1(2)e108.4(2)
ꢁ
PdeN2
PdeC30
FeeCg1
FeeCg2
C11eO
C11eN
C1eC11
N1eC24
PeC
ca. 0.14 A longer than in 4.
The geometry of the compensating SbFꢀ6 anion is rather unex-
ꢁ
ceptional (SbeF 1.858(3)e1.885(3) A, FeSbeF angles 88.2(1)e91.2
1.349(5)
1.458(6)
OeC11eN1
jc
1.422(5)
1.802(4)e1.826(4)
PdePeCd
CePeCe
a
Definition of the ring planes: Cp1 ¼ C(1e5), Cp2 ¼ C(6e10), PdL4 ¼
{Pd,P,O,N2,C30}. Cg1 and Cg2 are centroids of the rings Cp1 and Cp2, respectively.
b
Torsion angle C1eCg1eCg2eC6.
Dihedral angle of the Cp1 and {C11,O,N} planes.
The range of PdePeC(6,12,18) angles.
The range of C6ePeC(12,18) and C12ePeC18 angles.
c
d
e
Fig. 5. The CeH/F contacts operating in the crystals of complex 9. For clarity, only the
relevant hydrogen atoms and pivotal carbons from the PPh2 moiety are shown. The
prime- and double prime-labelled atoms are generated by the (x, 1/2 ꢀ y, 1/2 þ z) and
(ꢀx, 1 ꢀ y, 1 ꢀ z) symmetry operations, respectively. Some additional interactions,
absent in this figure, are discussed in the text.
Fig. 4. A view of the molecular structure of 9 showing the atom labelling scheme and
displacement ellipsoids at 30% probability level.

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P. Stepnicka et al. / Journal of Organometallic Chemistry 695 (2010) 2423e2431
2428
Table 5
Selected crystallographic data, data collection and structure refinement parameters for 4, 5$2Et2O and 9.
Compound
4
5$2Et2O
9
Formula
C
29H30FeNO2P
C66H68Cl2Fe2N2O4P2Pde
1304.16
C38H36F6FeN2OPPdSbf
965.66
M [g molꢀ1
]
511.36
Crystal system
Space group
T [K]
Monoclinic
P21/n (no. 14)
150(2)
12.4534(2)
12.9372(2)
16.2744(3)
110.463(1)
2456.55(7)
4
1.383
0.706
0.424e0.836
37579
6.06
Monoclinic
P21/c (no. 14)
150(2)
11.6197(2)
24.6950(8)
10.5699(3)
101.027(2)
2977.0(1)
2
1.455
0.973
0.740e0.878
24129
4.19
Monoclinic
P21/c (no. 14)
150(2)
19.257(2)
10.7485(5)
17.142(2)
95.930(7)
3529.1(6)
4
1.817
1.782
0.676e0.823
31872
11.13
ꢁ
a [A]
ꢁ
b [A]
ꢁ
c [A]
b
[ꢂ]
3
ꢁ
V [A ]
Z
Dcalc [g mLꢀ1
]
m
(MoK
a
) [mmꢀ1
]
T-rangea
Diffractions total
Rint [%]b
Unique diffractions
Observedc diffractions
R (obsd diffrns) [%]c,d
5634
4830
4.01
4.89, 10.97
1.90, ꢀ0.46
773800
6782
5288
5.12
6.65, 15.13
3.23, ꢀ1.40
773801
7986
5796
4.12
7.62, 8.39
0.79, ꢀ1.17
773802
R, wR (all diffrns) [%]d
ꢁꢀ3
Dr [e A
]
CCDC entry
a
The range of absorption coefficients.
b
Rint ¼ SjF2o ꢀ F2o(mean)j/SFo2, where F2o(mean) is the average intensity of symmetry-equivalent diffractions.
c
d
e
f
Diffractions with Io > 2s(Io).
R ¼ SkFoj ꢀ jFck/SjFoj, wR ¼ [S{w(F2o ꢀ Fc2)2}/Sw(Fo2)2]1/2
C58H48Cl2Fe2N2O2P2Pd$2C4H10O (see Experimental).
[C38H36FeN2OPPd]SbF6.
.
3. Conclusion
recorded with a Nicolet 7600 (Thermo Fisher Scientific) spec-
trometer in the range 400e4000 cmꢀ1. Positive-ion electron impact
(EIþ) mass spectra including the high resolution (HR) data were
obtained with a GCT premier spectrometer (Waters). Electrospray
(ESI) mass spectra were recorded with a Bruker Esquire 3000
spectrometer. The samples were dissolved in dichloromethane and
diluted with methanol in excess.
As evidenced by the preparation of two new phosphinoferro-
cene carboxamides 2 and 3, the reaction of substituted lith-
ioferrocenes with isocyanates represents
a viable route to
functional ferrocene carboxamides. Compared to carbodiimide-
mediated amide coupling method, which is frequently used in the
synthesis of ferrocene carboxamides, a wide implementation of this
methodology could be hindered by the availability and properties
(solubility) of the required isocyanates. However, its use seems to
be warranted for amines (e.g., aromatic), which are difficult to
couple under conventional conditions.
The coordination study performed with ligand 3 and platinum
and palladium as the metals expectedly demonstrated that this
phosphine-amide binds to these soft metals preferentially via its
soft phosphorus donor atom while the carbamoyl unit remains
uncoordinated and takes part in intermolecular interactions. Yet,
a P,O-chelate coordination of the same ligand can be readily
imparted after creating a free coordination site at the central atom,
e.g., via removal of an auxiliary ligand.
4.2. Preparation of 10-(diphenylphosphino)-1-
(N-cyclohexylcarbamoyl)ferrocene (2)
n-Butyllithium (0.5 mL 2.5 M in hexanes, 1.3 mmol) was added
slowly to a solution of bromide 1 (450 mg, 1.0 mmol) in dry tetra-
hydrofuran (20 mL) while cooling to ca. ꢀ78 ꢂC (dry ice/ethanol
bath). After stirring at this temperature for 50 min, neat cyclohexyl
isocyanate (150 mg, 1.2 mmol) was introduced and stirring was
continued overnight at room temperature. The resultant orange-
brown mixture was quenched with water and brine (10 mL each)
and extracted with diethyl ether (2 ꢃ 30 mL). Combined organic
layers were dried over MgSO4 and evaporated under vacuum. The
residue was purified by chromatography on a silica gel column
using dichloromethane/methanol (50:1 v/v) as the eluent. The first
band containing only (diphenylphosphino)ferrocene was discarded
and the following one containing the desired amide was collected
and evaporated under vacuum. Yield of 2: 334 mg (69%), orange
solid.
Prolonged elution (with the same solvent mixture) led to the
development of an additional minor orange band due to phosphine
oxide 4. This band was also collected and evaporated to afford crude
4, which was subsequently crystallised from ethyl acetate/hexane
at 4 ꢂC. The separated crystals were filtered off, washed succes-
sively with ethyl acetate/hexane (1:1 v/v) and pentane, and dried
under vacuum. Yield of 4: 9 mg (2%), orange brown crystalline solid.
4. Experimental
4.1. Materials and methods
Syntheses were performed under an argon atmosphere. Tetra-
hydrofuran was distilled from potassium/benzophenone ketyl.
Dichloromethane and chloroform were dried over anhydrous
K2CO3 and distilled afterwards. 10-(Diphenylphosphino)-1-bromo-
ferrocene (1) [9a], [MCl2(cod)] (M ¼ Pd or Pt) [20], and [{(LNC
)
PdCl}2] (LNC ¼ [2-(dimethylamino-
kN)methyl]phenyl-k
C1) [21]
were prepared by literature methods. Other chemicals and
solvents were used as received from commercial sources.
NMR spectra were measured on a Varian Unity Inova 400
spectrometer (1H, 399.95; 13C, 100.58; P, 161.90 MHz) at 25 ꢂC.
4.2.1. Analytical data for 2
31
Chemical shifts (
d
/ppm) are given relative to internal SiMe4 (13C and
1H NMR (CDCl3):
d 1.04e2.00 (m, 10H, CH2 of C6H11), 3.84e3.93
1H) or to external 85% aqueous H3PO4
(
31P). Infrared spectra were
(m, 1H, CH of C6H11), 4.04 (vt, J0 ¼ 1.8 Hz, 2H, fc), 4.18 (vt, J0 ¼ 1.9 Hz,

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P. Stepnicka et al. / Journal of Organometallic Chemistry 695 (2010) 2423e2431
2429
2H, fc), 4.40 (vt, J0 ¼ 1.8 Hz, 2H, fc), 4.54 (vt, J0 ¼ 1.9 Hz, 2H, fc), 5.78
321 (32, [C5H4PPhFeO]þ), 305 (10, [C5H4PPh2Fe]þ), 288 (11), 287
(5), 227 (4), 226 (8), 201 (5, [Ph2PO]þ), 197 (3), 183 (5,
[PPh2 ꢀ 2H]þ), 171 (12), 170 (8), 141 (2). HR MS calc. for
3
(d, JHH ¼ 8.1 Hz, 1H, NH), 7.31e7.40 (m, 10H, PPh2). 31P{1H} NMR
(CDCl3):
d
ꢀ16.9 (s). 13C{1H} NMR (CDCl3):
d 24.93 (s, 2 C, CH2 of
ꢁ
C6H11), 25.61 (s, 1C, CH2 of C6H11), 33.47 (s, 2C, CH2 of C6H11), 48.25
(s, 1C, CH of C6H11) 69.56 (s, 2C, CH of fc), 71.35 (s, 2C, CH of fc),
72.86 (d, JPC ¼ 4 Hz, 2C, CH of fc), 74.42 (d, JPC ¼ 15 Hz, 2C, CH of fc),
128.27 (d, 3JPC ¼ 6 Hz, 4C, CHm of PPh2), 128.75 (s, 2C, CHp of PPh2),
C29H2456FeNOP (Mþ ) 489.0945, found 489.0952. Anal. Calc. for
C29H24PFeON (489.3): C 71.18, H 4.94, N 2.86%. Found: C 70.86, H
4.91, N 2.76%.
133.44 (d, JPC ¼ 20 Hz, 4C, CHo of PPh2), 138.34 (d, 1JPC ¼ 9 Hz, 2C,
4.4. Preparation of trans-dichloridobis[10-(diphenylphosphino-
kP)-
1-(N-phenylcarbamoyl)ferrocene]palladium(II) (5)
2
Cipso of PPh2), 168.71 (s, 1C, C]O); signals due to Cipso(fc) are
probably obscured by the solvent resonance. IR (neat): n 3320 br s,
3069 m, 3052 m, 2931 s, 2853 s,1699 m, 1629 s, 1541 s, 1478 w, 1451
w, 1434 m, 1380 m, 1319 m, 1181 m, 1161 m, 1027 s, 891 m, 832 s,
820 m, 747 s, 697 s, 495 s, 453 w cmꢀ1. ESI ꢄ MS: m/z 495/496 (Mþ/
[M þ H]þ), 518 ([M þ Na]þ), 534 ([M þ K]þ); 494 ([M ꢀ H]ꢀ). EIþ MS:
Amide 3 (19.6 mg, 0.04 mmol) and [PdCl2(cod)] (5.7 mg,
0.02 mmol) were dissolved in chloroform (10 mL) to give a red
solution. The mixture was stirred for 2.5 h and layered with diethyl
ether. During crystallisation at 4 ꢂC over several days, the mixture
deposited a solid, which was filtered off, washed with diethyl ether
and dried under vacuum to afford 5$0.35CHCl3 as an orange-brown
microcrystalline solid (16 mg, 69%).
ꢁ
m/z (relative abundance) 497 (6), 496 (44), 495 (76, Mþ ), 494 (6),
493 (10), 414 (6), 413 (44), 412 (84, [M ꢀ Cy]þ), 410 (8), 401 (18), 400
(83), 399 (25), 398 (8), 397 (7), 386 (11), 370 (4), 322 (33), 321 (100,
[C5H4PPh2FeO]þ), 320 (6), 319 (12), 305 (12, [C5H4PPh2Fe]þ), 304
(5), 303 (12), 295 (12), 294 (74), 229 (4), 227 (7), 226 (16), 202 (13),
201 (89, [Ph2PO]þ), 197 (11), 183 (11, [PPh2 ꢀ 2H]þ), 171 (21), 170
1H NMR (CDCl3):
2H, fc), 5.04 (br s, 2H, fc), 7.04e7.69 (m, 15H, NPh and PPh2), 7.85 (s,
1H, NH). 31P{1H} NMR (CDCl3):
3420 br m,
d 4.53 (br s, 2H, fc), 4.60 (br s, 2H, fc), 4.64 (br s,
d
þ16.3 (s). IR (Nujol):
n
ꢁ
(17), 121 (9). HR MS calc. for C29H3056FeNOP (Mþ ) 495.1414, found
1678 s, 1595 m, 1529 s, 1496 w, 1314 s, 1264 w, 1162 m, 1140 w, 1098
m, 839 w, 745 s, 689 s, 516 m, 497 m, 473 m cmꢀ1. ESIþ MS: m/z
1177/1179 ([M þ Na]þ), 1119/1120 ([M ꢀ Cl]þ), 1041/1043 ([PdCl(3)
(3 ꢀ H) þ Na]þ). Anal. Calc. for C58H48P2Fe2O2N2PdCl2$0.35CHCl3
(1197.7): C 58.51, H 4.07, N 2.34%. Found: C 58.44, H 4.29, N 2.18%.
495.1409.
4.2.2. Analytical data for 4
1H NMR (CDCl3):
d 1.21e2.03 (m, 10H, CH2 of C6H11), 3.87e3.95
(m, 1H, CH of C6H11), 4.11 (vq, J0 ¼ 1.9 Hz, 2H, fc), 4.20 (vt, J0 ¼ 2.0 Hz,
2H, fc), 4.60 (vq, J0 ¼ 1.8 Hz, 2H, fc), 5.12 (vt, J0 ¼ 1.9 Hz, 2H, fc),
7.51e7.80 (m, 10H, PPh2), 8.62 (d, 3JHH ¼ 8 Hz, 1H, NH). 31P{1H} NMR
4.5. Preparation of trans-dichloridobis[10-(diphenylphosphino-
kP)-
1-(N-phenylcarbamoyl)ferrocene]platinum(II) (6)
(CDCl3):
d
þ30.6 (s). 13C{1H} NMR (CDCl3):
d 25.36 (s, 2C, CH2 of
C6H11), 25.67 (s, 1C, CH2 of C6H11), 33.10 (s, 2C, CH2 of C6H11), 48.65
(s, 1C, CH of C6H11), 70.37 (s, 2C, CH of fc), 70.77 (s, 2C, CH of fc),
72.40 (d, JPC ¼ 10 Hz, 2C, CH of fc), 75.41 (d, JPC ¼ 13 Hz, 2C, CH of fc),
128.40 (d, 3JPC ¼ 12 Hz, 4C, CHm of PPh2), 131.54 (d, 2JPC ¼ 10 Hz, 2C,
Aqueous solution of Na2[PtCl4] (7.7 mg, 0.02 mmol in 0.5 mL of
water) was added to a solution of amide 3 (20 mg, 0.04 mmol) in
glacial acetic acid (10 mL), causing immediate separation of an
orange precipitate. The mixture was stirred for 1 h and then heated
until the solids dissolved. The mixture was filtered (PTFE syringe
4
CHo of PPh2), 131.88 (d, JPC ¼ 2 Hz, 4C, CHp of PPh2), 133.07 (br d,
1JPC ¼ 107 Hz, 2C, Cipso of PPh2), 168.55 (s, 1C, C]O); signals due to
filter 0.45 mm) while hot and the filtrate was allowed to crystallise
Cipso(fc) are probably obscured by the solvent. IR (neat):
n
3240 br s,
by slow cooling to 4 ꢂC. The separated crystalline product was
filtered off, washed sequentially with 50% aqueous acetic acid and
water, and dried under vacuum to afford the solvate 6$3AcOH as an
orange crystalline solid (20 mg, 40%).
3077 m, 3057 m, 2931 s, 2853 s, 1639 s, 1544 s, 1437 m, 1318 m, 1188
s, 1163 s, 1119 s, 1029 m, 837 m, 821 m, 750 s, 723 s, 701 s, 568 s, 526
s, 505 s cmꢀ1. Anal. Calc. for C29H30PFeO2N (511.4): C 68.11, H 5.91, N
2.74%. Found: C 68.32, H 6.02, N 2.53%.
1H NMR (CDCl3): 4.52 (vt, J0 z 1.8 Hz, 2H, fc), 4.61 (vt, J0 z 1.8 Hz,
d
2H, fc), 4.66 (vt, J0 z 1.8 Hz, 2H, fc), 5.04 (vt, J0 z 1.8 Hz, 2H, fc),
4.3. Preparation of 10-(diphenylphosphino)-1-(N-phenylcarbamoyl)
ferrocene (3)
7.05e7.70 (m, 15H, NPh and PPh2), 7.73 (s, 1H, NH). 31P{1H} NMR
(CDCl3):
d
þ11.1 (s with 195Pt satellites, 1JPtP ¼ 2605 Hz). IR (Nujol):
n
3330 br s,1713 s,1632 s,1600 s,1544 s,1500 s,1377 s,1325 m,1275 m,
1036 w, 752 m, 694 w, 527 w cmꢀ1. ESI ꢄ MS: m/z 1267 ([M þ Na]þ);
1243 ([M ꢀ H]ꢀ). Anal. Calc. for C58H48P2Fe2O2N2PtCl2$3AcOH
(1424.8): C 53.95, H 4.24, N 1.97%. Found: C 53.71, H 4.14, N 1.96%.
Phosphine-amide 3 was prepared similarly starting with 1
(450 mg, 1.0 mmol), n-butyllithium (0.5 mL 2.5 M in hexanes,
1.3 mmol)andphenylisocyanate(142 mg,1.2 mmol). Theworkupand
chromatographic isolation as described above (a second band was
collected) gave phosphinoamide 3 as an orange foam (155 mg, 32%).
4.6. Preparation of cis-dichloridobis[10-(diphenylphosphino-
kP)-1-
(N-phenylcarbamoyl)ferrocene]platinum(II) (7)
1H NMR (CDCl3):
d
4.12 (vq, J0 ¼ 1.9 Hz, 2H, fc), 4.27 (vt,
J0 ¼ 1.9 Hz, 2H, fc), 4.48 (vt, J0 ¼ 1.9 Hz, 2H, fc), 4.68 (vt, J0 ¼ 1.9 Hz,
2H, fc), 7.09e7.64 (m, 15H, NPh and PPh2), 7.75 (s, 1H, NH). 31P{1H}
Amide 3 (20 mg, 0.04 mmol) and [PtCl2(cod)] (7.5 mg, 0.02 mmol)
were dissolved in chloroform (10 mL). The mixture was stirred for 2 h
and then layered with diethyl ether. Crystallisation at 4 ꢂC over
several days afforded a crystalline solid which was filtered off,
washed with diethyl ether, and dried under vacuum to give
7$0.5CHCl3 (orange microcrystalline solid; 16.5 mg, 33%).
NMR (CDCl3):
d
ꢀ16.7 (s). 13C{1H} NMR (CDCl3):
d 69.90 (s, 2C, CH of
fc), 71.80 (s, 2C, CH of fc), 72.80 (d, JPC ¼ 4 Hz, 2C, CH of fc), 74.55 (d,
JPC ¼ 13 Hz, 2C, CH of fc), 119.84 (s, 2C, CHm of NPh), 123.97 (s, 1C
CHp of NPh), 128.38 (d, 3JPC ¼ 6 Hz, 4C, CHm of PPh2), 128.92 (s, 2C,
CHp of PPh2), 129.01 (s, 2C CHo of NPh), 133.47 (d, 2JPC ¼ 20 Hz, 4C,
CHo of PPh2), 138.08 (d, 1JPC ¼ 9 Hz, 2C, Cipso of PPh2), 138.28 (s, 1C,
Cipso of NPh), 168.31 (s, 1C, C]O); signals due to ferrocene Cipso are
1H NMR (CDCl3):
d
3.75 (vt, J0 ¼ 1.9 Hz, 2H, fc), 4.07 (br s, 2H, fc),
4.26 (br s, 2H, fc), 4.66 (vt, J0 ¼ 1.9 Hz, 2H, fc), 7.06e7.76 (m, 15H,
obscured by the solvent resonance. IR (Nujol):
n
3300 br s, 1650 s,
NPh and PPh2), 9.39 (s, 1H, NH). 31P{1H} NMR (CDCl3):
d
þ9.4 (s
1637 s, 1597 s, 1528 s, 1499 s, 1434 s, 1320 s, 1272 m, 1161 w, 1141 w,
1028 m, 743 s, 695 s, 496 s, 450 m cmꢀ1. ESI ꢄ MS: m/z 489 (Mþ),
512 ([M þ Na]þ); 488 ([M ꢀ H]ꢀ). EIþ MS: m/z (relative abundance)
with 195Pt satellites, 1JPtP ¼ 3785 Hz). IR (Nujol):
n 3300 br m, 1670 s,
1641 s, 1597 s, 1534 s, 1316 s, 1269 m, 1164 m, 834 w, 755 m, 690 s,
489 s cmꢀ1. ESI ꢄ MS: m/z 1209 ([M ꢀ Cl]þ), 1173 ([M ꢀ 2Cl]þ); 1243
([M ꢀ H]ꢀ). Anal. Calc. for C58H48P2Fe2O2N2PtCl2$0.5CHCl3
(1304.3): C 53.87, H 3.75, N 2.15. Found: C 53.60, H 3.87, N 2.10%.
ꢁ
491 (5), 490 (32), 489 (100, Mþ ), 488 (8), 487 (7), 462 (4), 412 (5,
[M ꢀ Ph]þ), 397 (5, [Ph2PfcCO]þ), 386 (8), 384 (3), 344 (6), 322 (10),

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P. Stepnicka et al. / Journal of Organometallic Chemistry 695 (2010) 2423e2431
2430
4.7. Preparation of [SP-4-4]-chlorido{[(2-dimethylamino-
methyl]phenyl- P)-1-
C1}-[10-(diphenylphosphino-
(N-phenylcarbamoyl)ferrocene]palladium(II) (8)
k
N)
were corrected for absorption using the methods incorporated in
the diffractometer software.
k
k
The structures were solved by direct methods (SIR97, Ref. [22])
and refined by full-matrix least-squares based on F2 (SHELXL97, Ref.
[23]). Non-hydrogen atoms were refined with anisotropic
displacement parameters. Amide hydrogens (H1N) were identified
on the difference electron density maps and refined as riding atoms
with unconstrained isotropic displacement parameters. All other
hydrogen atoms were included in their calculated positions and
treated as riding atoms with Uiso(H) assigned to a multiple of Ueq of
their bonding carbon atom. The solvent molecules in the structure
of 5$2Et2O were found to be severely disordered in structural voids
defined by the bulky complex molecules of the complex. Their
contribution to the overall diffraction intensity was modelled by
SQUEEZE routine as incorporated in PLATON program [24]. Within
Di-m-chloridobis{[(2-dimethylamino-
kN)methyl]phenyl-
k
C1}
dipalladium(II) (11 mg, 0.02 mmol) and amide
3
(20 mg,
0.04 mmol) were dissolved in dry chloroform (10 mL). The resul-
tant solution was stirred for 2 h, partially evaporated under
vacuum, and precipitated with pentane (15 mL). The mixture was
cooled to ꢀ18 ꢂC overnight, and the precipitate was filtered off,
washed with pentane and dried under vacuum to give complex
8$0.7CHCl3 as an orange solid (19 mg, 63%).
4
1H NMR (CDCl3):
d
2.86 (d, JPH ¼ 2.7 Hz, 6H, NMe2), 4.14 (d,
4JPH ¼ 2.4 Hz, 2H, NCH2), 4.46e4.50 (m, 4H, fc), 4.67 (vt, J0 ¼ 1.9 Hz,
2H, fc), 5.21 (vt, J0 ¼ 1.9 Hz, 2H, fc), 6.24 (ddd, J ¼ 7.8, 6.5, 1.2 Hz, 1H,
C6H4), 6.35 (td, J ¼ 7.5, 1.4 Hz, 1H, C6H4), 6.81 (td, J ¼ 7.4, 1.1 Hz, 1H,
C6H4), 7.00 (dd, J ¼ 7.4, 1.6 Hz,1H, C6H4) 7.06e7.79 (m, 15H, NPh and
3
ꢁ
the 714 A of void space per the unit cell, a total of 145 electrons
were calculated, compared to the 168 electrons expected for four
molecules of diethyl ether.
PPh2), 8.59 (s, 1H, NH). 31P{1H} NMR (CDCl3):
d
þ32.9 (s). IR (Nujol):
n
3300 br s, 1666 s, 1596 s, 1529 s, 1315 s, 1164 m, 1099 m, 1028 m,
Relevant crystallographic data are summarised in Table 5.
Geometric parameters and structural drawings were obtained with
a recent version of the PLATON program [24]. All numerical values
are rounded with respect to their estimated standard deviations
(esd’s) given with one decimal; parameters involving fixed
hydrogen atoms are given without esd’s.
844 m, 693 s cmꢀ1. ESI ꢄ MS: m/z 729 ([M ꢀ Cl]þ); 763 ([M ꢀ H]ꢀ),
488 ([3 ꢀ H]ꢀ). Anal. Calc. for C38H36PFeON2PdCl$0.7CHCl3 (848.9):
C 54.75, H 4.36, N 3.30. Found: C 54.74, H 4.45, N 3.24%.
4.8. Preparation of [SP-4-3]-{[(2-dimethylamino-
phenyl- P)-1-(N-phenylcarbamoyl-
C1}-[10-(diphenylphosphino-
O)ferrocene]palladium(II) hexafluoroantimonate (9)
kN)methyl]
k
k
Acknowledgements
k
This work is a part of the long-term research project of Faculty of
Science, Charles University in Prague supported by the Ministry of
Education, Youth and Sports of the Czech Republic (project no.
MSM0021620857).
Di-
m
-chloridobis{[(2-dimethylamino-
k
N)methyl]phenyl-
k
C1}
dipalladium(II) (27.5 mg, 0.05 mmol) and amide
3
(20 mg,
0.04 mmol) were dissolved in dry dichloromethane (3 mL) and the
resulting solution was stirred at room temperature for 15 min.
Then, a solution of Ag[SbF6] (35 mg, 0.10 mmol) in dry tetrahy-
drofuran (1 mL) was added, causing separation of an off-white
precipitate (AgCl). The mixture was stirred for another 15 min,
Appendix A. Supplementary material
CCDC 773800e773802 contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre via www.
ccdc.cam.ac.uk/data_request/cif.
filtered (0.45 mm PTFE syringe filter), and the filtrate was layered
with diethyl ether. Subsequent crystallisation by liquid-phase
diffusion at 4 ꢂC afforded orange-brown crystalline solid, which
was isolated by suction, washed with diethyl ether and dried under
vacuum. Yield: 83 mg (86%), rusty orange crystals.
1H NMR ((CD3)2SO):
d
2.68 (d, 4JPH ¼ 2.7 Hz, 6H, NMe2), 3.97 (vq,
References
J ¼ 2.0 Hz, 2H, fc), 4.17 (unresolved d, 2H, NCH2), 4.47 (vt, J ¼ 2.0 Hz,
2H, fc), 4.57 (m, 2H, fc), 5.15 (vt, J ¼ 2.0 Hz, 2H, fc), 6.28 (ddd, J ¼ 7.6,
6.2, 1.0 Hz, 1H, C6H4), 6.47 (td, J ¼ 7.6, 1.6 Hz, 1H, C6H4), 6.90 (td,
J ¼ 7.4, 1.0 Hz, 1H, C6H4), 7.07 (dd, J ¼ 7.4, 1.6 Hz, 1H, C6H4),
7.09e7.75 (m, 15H, NPh and PPh2), 9.70 (s, 1H, NH). 31P{1H} NMR
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
[1] (a) L. Meca, D. Dvorák, J. Ludvík, I. Císarová, P. Stepnicka, Organometallics 23
(2004) 2541;
ꢀ
ꢀ
ꢀ
ꢀ
(b) P. Stepnicka, J. Schulz, I. Císarová, K. Fejfarová, Collect. Czech. Chem.
Commun. 72 (2007) 453;
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
(c) M. Lamac, I. Císarová, P. Stepnicka, Eur. J. Inorg. Chem. (2007) 2274;
ꢀ
ꢀ
ꢀ
(d) J. Kühnert, M. Dusek, J. Demel, H. Lang, P. Stepnicka, Dalton Trans. (2007)
2802;
((CD3)2SO):
d
þ31.0 (s). IR (Nujol):
n 3394 m, 1611 s, 1594 s, 1580 m,
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
(e) M. Lamac, J. Tauchman, I. Císarová, P. Stepnicka, Organometallics 26 (2007)
5042;
1337 s,1282 m,1240 w,1167 m,1096 m,1038 w,1027 w,1019 w, 992
w, 973 w, 863 w, 876 m, 836 w, 827 w, 761 s, 752 w, 741 m, 695 s,
655 s, 639 s, 533 m, 522 m, 515 m, 507 s, 474 m cmꢀ1. ESI ꢄ MS: m/z
729 ([(LNC)Pd(3)]þ); 488 ([3 ꢀ H]ꢀ), 235/237 ([SbF6]ꢀ). Anal. Calc.
for C38H36F6FeN2OPPdSb (965.7): C 47.26, H 3.76, N 2.90%. Found: C
46.91, H 3.94, N 2.78%.
ꢀ
ꢀ
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(f) J. Kühnert, M. Lamac, J. Demel, A. Nicolai, H. Lang, P. Stepnicka, J. Mol. Catal.
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(j) P. Stepnicka, M. Krupa, M. Lamac, I. Císarová, J. Organomet. Chem. 694
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ꢀ
4.9. X-ray crystallography
ꢀ
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(l) M. Lamac, J. Tauchman, S. Dietrich, I. Císarová, H. Lang, P. Stepnicka, Appl.
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[2] For examples from other laboratories, see: (a) W. Zhang, T. Shimanuki, T. Kida,
Y. Nakatsuji, I. Ikeda, J. Org. Chem. 64 (1999) 6247;
Single crystals suitable for diffraction analysis were selected
directly from the reaction batch (9: orange-brown prism,
0.19 ꢃ 0.30 ꢃ 0.44 mm3), or grown by crystallisation from ethyl
acetate/hexane (4: orange prism, 0.28 ꢃ 0.30 ꢃ 0.80 mm3) or chlo-
roform/diethyl ether (5$2Et2O: red block, 0.25 ꢃ 0.55 ꢃ 0.60 mm3).
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(g) H. Jendralla, E. Paulus, Synlett (1997) 471.
Full-set diffraction data (ꢄh ꢄ k ꢄ l, 2
q
ꢅ 55ꢂ, data completeness
ꢆ98.5%) were collected with a Nonius KappaCCD diffractometer
equipped with a Cryostream Cooler (Oxford Cryosystems) using
[3] This method is widely used for conjugation of biomolecules with ferrocene-
ꢁ
ꢀ
ꢀ ꢀ
carboxylic acids: (a) N. Metzler-Nolte, M. Salmain, in: P. Stepnicka (Ed.), The
graphite monochromatised MoK
a
radiation (
l
¼ 0.71073 A) and

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2431
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Bioorganometallic Chemistry of Ferrocene in Ferrocenes: Ligands, Materials
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Principles and Progress: 31P and 13C NMR of Transition Metal Phosphine
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ꢀ
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[5] N. Weliky, E.S. Gould, J. Am. Chem. Soc. 79 (1957) 2742.
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(1901) 38. For other early examples of the preparation of carboxamides from
organolithium or Grignard reagents and isocyanates, see:
(b) U. Schöllkopf, Methoden der organischen Chemie (Houben-Weyl), fourth
ed., vol. XIII/1, Thieme, Stuttgart, 1970, p. 190;
(c) K. Nützel, Methoden der organischen Chemie (Houben-Weyl), fourth ed.,
vol. XIII/2a, Thieme, Stuttgart, 1973, p. 393.
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(b) D.W. Slocum, C.A. Jennings, T.R. Engelmann, B.W. Rockett, C.R. Hauser,
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[16] P. Stepnicka, J. Podlaha, R. Gyepes, M. Polásek, J. Organomet. Chem. 552 (1998)
293.
[17] For NMR data of (LNC)Pd-complexes with phosphinoferrocene ligands, see: (a)
J.-M. Ma, Y. Yamamoto, Inorg. Chim. Acta 299 (2000) 164;
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
(b) P. Stepnicka, I. Císarová, Organometallics 22 (2003) 1728;
(c) P. Stepnicka, Inorg. Chem. Commun. 7 (2004) 426;
ꢀ ꢀ ꢀ ꢀ
(d) P. Stepnicka, M. Lamac, I. Císarová, Polyhedron 23 (2004) 921;
(e) P. Stepnicka, I. Císarová, Inorg. Chem. 45 (2006) 8785;
(f) P.I. StepnickaCísarová, Collect. Czech. Chem. Commun. 71 (2006) 215 See
also Refs. [1h,j].
ꢀ
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[18] K. Nakamoto, Infrared and Raman Spectra of Inorganic and Coordination
Compounds, Part A: Theory and Applications in Inorganic Chemistry, fifth ed.
Wiley, New York, 1997, part A, sect. II (chapter II-8) p. 214.
[19] Composition of the crystallised material and the ‘bulk’ product differ owing to
a different crystallisation procedure.
[8] M. Oberhoff, L. Duda, J. Karl, R. Mohr, G. Erker, R. Fröhlich, M. Grehl, Organ-
ometallics 15 (1996) 4005.
[9] (a) I.R. Butler, R.L. Davies, Synthesis (1996) 01350;
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
(b) P. Stepnicka, in: P. Stepnicka (Ed.), 1 -Functionalised Ferrocene Phos-
phines: Synthesis, Coordination Chemistry and Catalytic Applications in
Ferrocenes: Ligands, Materials and Biomolecules, Wiley, Chichester, 2008
(chapter 5) pp. 177e204 and references cited therein.
[20] D. Drew, J.R. Doyle, Inorg. Synth. 13 (1972) 47.
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[23] G.M. Sheldrick, SHELXL97. Program for Crystal Structure Refinement from
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ꢀ
ꢀ
ꢀ
ꢀ
[10] J. Podlaha, P. Stepnicka, J. Ludvík, I. Císarová, Organometallics 15 (1996) 543.
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[12] In the case of amide 2, this ion falls into the isotopic cluster due to a highly
strong fragment at m/z 400.