New developments in the studies of the reactivity of cyclometallated palladium(II) compounds with homo- ([P,P],[As,As]) and heterobidentate ([P,N],[P,O]) ligands

Article abstract of DOI:10.1016/j.jorganchem.2007.06.041

Treatment of the chloro-bridged dinuclear compounds [{Pd[RC₆H₃C(H){double bond, long}NCy-C2,N]}(μ-Cl)]₂ (R = 4-(COH), 1; R = 5-(COH), 2) with bidentate phosphorus or arsenic diphosphines or diarsine ligands in 1:1 molar ratio gave the dinuclear complexes [{Pd[RC₆H₃C(H){double bond, long}NCy-C2,N](Cl)}₂{μ-(o-Tol)₂P(CH₂)₂P(o-Tol)₂}] (R = 4-(COH), 3; R = 5-(COH), 4), [{Pd[RC₆H₃C(H){double bond, long}NCy-C2,N](Cl)}₂{μ-Ph₂PC₄H₂(NH)CH₂PPh₂}] (R = 4-(COH), 5; R = 5-(COH), 6) and [{Pd[RC₆H₃C(H){double bond, long}NCy-C2,N](Cl)}₂{μ-Ph₂As(CH₂)₂AsPh₂}] (R = 4-(COH), 7; R = 5-(COH), 8) with the homobidentate [P,P] and [As,As] ligands in a bridging mode. Treatment of 1 and 2 with the aminophosphine Ph₂P(CH₂)₂NH₂ yields the dinuclear complexes [{Pd[RC₆H₃C(H){double bond, long}NCy-C2,N](Cl)}₂{μ-Ph₂P(CH₂)₂NH₂}] (R = 4-(COH), 9; R = 5-(COH), 10). The analogous reactions carried out in a 1:2 molar ratio, in the presence of NH₄PF₆ or NaClO₄, gave the mononuclear compounds [Pd{RC₆H₃C(H){double bond, long}NCy-C2,N}{(o-Tol)₂P(CH₂)₂P(o-Tol)₂-P,P}][PF₆] (R = 4-(COH), 11; R = 5-(COH), 12), [Pd{RC₆H₃C(H){double bond, long}NCy-C2,N}{Ph₂PC₄H₂(NH)CH₂PPh₂-P,P}][ClO₄] (R = 4-(COH), 13; R = 5-(COH), 14) and [Pd{RC₆H₃C(H){double bond, long}NCy-C2,N}{Ph₂As(CH₂)₂AsPh₂-As,As}][ClO₄](R = 4-(COH), 15; R = 5-(COH), 16), with the [P,P] and [As,As] ligands chelated to the palladium atom. Treatment of 2 with Ph₂P(CH₂)₃NH₂ in a 1:2 molar ratio in acetone in the presence of NH₄PF₆ afforded the mononuclear compound [Pd{5-(COH)C₆H₃C(H){double bond, long}NCy-C2,N}{Ph₂P(CH₂)₃N({double bond, long}Me₂)-P,N}][PF₆], 17, via intermolecular condensation between the aminophosphine and the solvent. Condensation was precluded using toluene as solvent to give [Pd{RC₆H₃C(H){double bond, long}NCy-C2,N}{Ph₂P(CH₂)_nNH₂-P,N}][PF₆], (n = 3, R = 5-(COH), 18; n = 2, R = 4-(COH), 19; n = 2, R = 5-(COH), 20). Treatment of 1 and 2 with Ph₂P(C₆H₄)CHO in a 1:2 molar ratio in the presence of NH₄PF₆ gave the mononuclear complexes [Pd{RC₆H₃C(H){double bond, long}NCy-C2,N}{2-(Ph₂P)C₆H₄CHO-P,O}][PF₆] (R = 4-(COH), 21; R = 5-(COH), 22) with the palladium atom bonded to four different atoms (C, N, P, O) and a chelating [P,O] ligand. The crystal structures of compounds 7, 11, 15 and 21 have been determined by X-ray crystallography.

Full text of DOI:10.1016/j.jorganchem.2007.06.041

Journal of Organometallic Chemistry 692 (2007) 4197–4208
www.elsevier.com/locate/jorganchem
New developments in the studies of the reactivity of
cyclometallated palladium(II) compounds with homo- ([P,P],[As,As])
and heterobidentate ([P,N],[P,O]) ligands
a
a
a
a
´
´
´
´
Raquel Ares , Margarita Lopez-Torres , Alberto Fernandez , Digna Vazquez-Garcıa ,
b
b,
a
a,
*
*
´
´
M. Teresa Pereira , Jose M. Vila , Leticia Naya , Jesu´s J. Fernandez
a
Departamento de Quı´mica Fundamental, Universidade da Corun˜a, 15071 A Corun˜a, Spain
Departamento de Quı´mica Inorga´nica, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
b
Received 1 May 2007; received in revised form 8 June 2007; accepted 8 June 2007
Available online 29 June 2007
Abstract
Treatment of the chloro-bridged dinuclear compounds [{Pd[RC6H3C(H)@NCy-C2,N]}(l-Cl)]2 (R = 4-(COH), 1; R = 5-(COH), 2)
with bidentate phosphorus or arsenic diphosphines or diarsine ligands in 1:1 molar ratio gave the dinuclear complexes
[{Pd[RC6H3C(H)@NCy-C2,N](Cl)}2{l-(o-Tol)2P(CH2)2P(o-Tol)2}] (R = 4-(COH), 3; R = 5-(COH), 4), [{Pd[RC6H3C(H)@NCy-
C2,N](Cl)}2{l-Ph2PC4H2(NH)CH2PPh2}] (R = 4-(COH), 5; R = 5-(COH), 6) and [{Pd[RC6H3C(H)@NCy-C2,N](Cl)}2{l-Ph2-
As(CH2)2AsPh2}] (R = 4-(COH), 7; R = 5-(COH), 8) with the homobidentate [P,P] and [As,As] ligands in a bridging mode. Treatment
of 1 and 2 with the aminophosphine Ph2P(CH2)2NH2 yields the dinuclear complexes [{Pd[RC6H3C(H)@NCy-C2,N](Cl)}2-
{l-Ph2P(CH2)2NH2}] (R = 4-(COH), 9; R = 5-(COH), 10). The analogous reactions carried out in a 1:2 molar ratio, in the presence of
NH4PF6 or NaClO4, gave the mononuclear compounds [Pd{RC6H3C(H)@NCy-C2,N}{(o-Tol)2P(CH2)2P(o-Tol)2-P,P}][PF6] (R =
4-(COH), 11; R = 5-(COH), 12), [Pd{RC6H3C(H)@NCy-C2,N}{Ph2PC4H2(NH)CH2PPh2-P,P}][ClO4] (R = 4-(COH), 13; R = 5-
(COH), 14) and [Pd{RC6H3C(H)@NCy-C2,N}{Ph2As(CH2)2AsPh2-As,As}][ClO4](R = 4-(COH), 15; R = 5-(COH), 16), with the [P,P]
and [As,As] ligands chelated to the palladium atom.
Treatment of 2 with Ph2P(CH2)3NH2in a 1:2 molar ratio in acetone in the presence of NH4PF6 afforded the mononuclear compound
[Pd{5-(COH)C6H3C(H)@NCy-C2,N}{Ph2P(CH2)3N(@Me2)-P,N}][PF6], 17, via intermolecular condensation between the aminophos-
phine and the solvent. Condensation was precluded using toluene as solvent to give [Pd{RC6H3C(H)@NCy-C2,N}{Ph2P(CH2)nNH2-
P,N}][PF6], (n = 3, R = 5-(COH), 18; n = 2, R = 4-(COH), 19; n = 2, R = 5-(COH), 20). Treatment of 1 and 2 with Ph2P(C6H4)CHO
in a 1:2 molar ratio in the presence of NH4PF6 gave the mononuclear complexes [Pd{RC6H3C(H)@NCy-C2,N}{2-(Ph2P)C6H4CHO-
P,O}][PF6] (R = 4-(COH), 21; R = 5-(COH), 22) with the palladium atom bonded to four different atoms (C, N, P, O) and a chelating
[P,O] ligand. The crystal structures of compounds 7, 11, 15 and 21 have been determined by X-ray crystallography.
ꢀ 2007 Elsevier B.V. All rights reserved.
Keywords: Palladium; Metallation; Diphosphines; Diarsines; [P,N] ligands; [P,O] ligands; X-ray diffraction
1. Introduction
of transition metals has been extensively investigated. Tet-
radentate [C,N,C,N] Schiff bases generally undergo double
metallation to give compounds with two metal atoms per
organic ligand [6–16], however, as we have reported previ-
ously, in the case of the potentialy tetradentate ligands
derived from isophthalaldehyde, 1,3-(CyN@CH)2C6H4,
and terephthalaldehyde, 1,4-(CyN@CH)2C6H4, they
may be mono- or dimetallated depending on the reaction
In the last decades much attention has been devoted to
the study of cyclometallation compounds [1–5]. In particu-
lar, cyclometallation of Schiff-base ligands with a wide range
*
Corresponding authors.
E-mail address: qideport@usc.es (J.M. Vila).
0022-328X/$ - see front matter ꢀ 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2007.06.041

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R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
conditions [17–19]. Thus, treatment with palladium(II) ace-
tate in acetic acid gave the monocyclometallated complexes
1 and 2 after cleavage of one C@N double bond, and we
have studied the reactivity of these cyclometallated com-
plexes towards different mono and bidentate ligands
[20–24]. Herein, we present further developments of our
investigations regarding the reactivity of 1 and 2 with the
new group 15 donor atom bidentate ligands: the diphos-
phines, 1,2-bis(di-o-tolylphosphino)ethane and 4-(diph-
R = 5-(COH), 2) with tertiary diphosphines in 1:1 molar
ratio gave the dinuclear compounds [{Pd[RC6H3C(H)@
NCy-C2,N](Cl)}2{l-(o-Tol)2P(CH2)2P(o-Tol)2}]
(R = 4-
(COH), 3; R = 5-(COH), 4); and [{Pd[RC6H3C(H)@NCy-
C2,N](Cl)}2{l-Ph2PC4H2(NH)CH2PPh2}] (R = 4-(COH),
5; R = 5-(COH), 6) with the diphosphine in a bridging mode.
The IR spectrum showed the shift of the C@N stretch
towards lower wavenumbers, as compared to the free
Schiff-base ligand (ca. 1620 vs. 1630 cmꢀ1), indicating
nitrogen coordination of the C@N group [46]. A band ca.
1690 cmꢀ1 was assigned to the uncoordinated formyl group
[47]. The MS-FAB spectrum showed peaks assigned
to [LPd(PP)]+ and [(L-CHO)Pd]+ (L = cyclometallated
ligand), which were characteristic clusters of isotopic peaks
covering about 10 m/z units, due to the presence of the
numerous palladium isotopes [48,49].
enylphosphino)-2-(diphenylphosphinomethyl)pyrrol,
well the diarsine: 1,2-bis(diphenylarsino)ethane.
as
Furthermore, there is a great interest in metal complexes
with diphosphines due to the versatility of their electronic
and steric properties [25–28], and there has also been a
growing interest in bidentate ligands which combine both
hard and soft donor atoms [29–34]. Among these are the
heterofunctionalized phosphines with phosphorus (soft)
and oxygen or nitrogen (hard) donor atoms. These ligands
exhibit partial lability making them particularly interesting
in homogeneous catalysis [35–39], with coordination alter-
nating between bidentate and monodentate, which gener-
ates vacant sites on the metal ion for potential substrate
binding. Consequently, we decided to study the behavior
of cyclometallated complexes 1 and 2 towards heterofunc-
tionalized [P,N] and [P,O] phosphines: 2-(diphenylphosph-
ino)ethylamine, 2-(diphenylphosphino)-1-propylamine and
2-(diphenylphosphino)benzaldehyde. The latter is one of
the simplest bidentate [P,O] ligands and it exhibits two
binding modes when the PCHO group acts as a chelating
ligand [40], with the aldehyde moiety bonded to the metal
in a r-fashion through the oxygen atom [41–43], or in a
p-fashion through the carbon–oxygen double bond [44,45].
The 31P–{1H} NMR spectrum of 3 and 4 showed only
one singlet at d 28.50, in accordance with equivalent phos-
phorus nuclei, indicating the symmetric nature of the com-
plexes. The singlet was shifted to higher frequency from the
free phosphine, in agreement with phosphorus coordina-
tion to metal center [50]. However, the 31P–{1H} NMR
spectrum of 5 and 6 showed two singlets ca. d 40, assigned
to the two non-equivalent phosphorus atoms, consequent
on the asymmetric structure of the diphosphine,
Ph2PC4H2(NH)CH2PPh2. This was also reflected in the
1H NMR spectrum (vide infra).
1
A singlet resonance in the H NMR spectrum at d 9.04
(3) and d 9.81 (4), respectively, was assigned to the CHO
proton. In the former case the resonance was shifted to
lower frequency from the starting product by 0.94 ppm,
due to the shielding effect of the phosphine tolyl rings, in
agreement with a P trans to N arrangement, typical of these
reactions and within the terms of the ‘‘transphobic effect’’
coined by Vicente et al. [51]. A broad signal ca. d 6.60
was assigned to the H3 proton, coupled to the phosphorus
atom and shifted to lower frequency from the starting
product ca. 1.3 and 1.0 ppm, respectively, due to the shield-
ing effect of the phosphine tolyl rings.
Ph2P
H
Ph2P
C
H
O
M
O
M
1
The H NMR spectrum for 5 and 6 showed two COH
The coordination mode of the aldehyde is dependent on
the transition metal, the oxidation state and the other
ligands present in the compound. Herein we report a
detailed description of this chemistry together with the
crystal structure of the first cyclometallated palladium
PCHO complex containing a r-bonded aldehyde group.
resonances as singlets, d 9.10, d 9.33 (5) and d 9.72, d
9.79 (6), as well as to two doublets, ca. d 6.60 and d 6.90,
ascribed to the H3=H30 protons coupled to the 31P nucleus;
thus putting forward the asymmetry of the diphosphine.
The 13C–{1H} NMR spectrum of 5 showed two dou-
blets at d 170.6 and d 172.5 and two singlets at d 153.9
and d 154.3 were assigned to the C ¼ N=C0 ¼ N and the
C2=C20 carbon atoms, respectively, downfield shifted from
the spectrum of the free ligand (ca. 25 and 14 ppm, also
respectively) thereby confirming cyclometallation. The
C3=C30 and C4=C40 resonances appeared as four doublets
at d 139.4, d 139.8 ½3JðPC3=PC30Þ ¼ 9:6; 9:8 Hzꢁ, and d
135.8, d 136.2 ½4JðPC4=PC40Þ ¼ 4:2; 4:3 Hzꢁ by coupling
to the phosphorus nuclei.
2. Results and discussion
For the convenience of the reader the compounds and
reactions are shown in Schemes 1 and 2. The compounds
described in this paper were characterized by elemental
analysis (C,H,N), by mass spectrometry, and by IR and
1H, 31P–{1H} and (in part) 13C–{1H} NMR spectroscopy
(data in Section 3).
Reaction of 1 and 2 with the diarsine Ph2As(CH2)2AsPh2
in 1:1 molar ratio afforded the dinuclear complexes
[{Pd[RC6H3C(H)@NCy-C2,N](Cl)}2(l-Ph2As(CH2)2As-
Treatment of the chloro-bridged dinuclear complexes
[{Pd[RC6H3C(H)@NCy-C2,N]}(l-Cl)]2 (R = 4-(COH), 1;

R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
4199
Cy
N
Cy
H
Cl
H
N
Cl
P
N
H
Pd
Pd
P
Ph2
R
R
(o-Tol)2
R
R
PPh2
(o-Tol)2
P
Pd
Pd
Cl
H
N
H
N
Cl
Cy
Cy
3, R = 4-COH
4, R = 5-COH
5, R = 4-COH
6, R = 5-COH
ii
i
4
5
6
3
2
R
Cl
1
Pd
2
H
N
7
8
12
11
9
10
1, R = 4-COH
2, R = 5-COH
iv
iii
Cy
N
Cy
Cl
H
Cl
N
N
H
4
Pd
Pd
2'
3'
5
6
1'
3
2
6'
Ph2
As
As
Ph2
R
R
Ph2
P
R
H2
R
1
5'
Pd
Pd
4'
H
N
Cl
H
N
Cy
Cl
Cy
7, R = 4-COH
8, R = 5-COH
9, R = 4-COH
10, R = 5-COH
Scheme 1. (i) (o-Tol)2P(CH2)2P(o-Tol)2 (1:1), dichloromethane; (ii) Ph2PC4H2(NH)CH2PPh2 (1:1), dichloromethane (5), chloroform (6); (iii)
Ph2As(CH2)2AsPh2 (1:1), dichloromethane; (iv) Ph2P(CH2)2NH2 (1:1), acetone.
Ph2)] (R = 4-(COH), 7; R = 5-(COH), 8) which were fully
{l-Ph2P(CH2)2NH2}] (R = 4-(COH), 9; R = 5-(COH),
10). A singlet at d 53.01 in the 31P–{1H} NMR spectrum
confirmed phosphorus coordination to the metal center.
In the 1H NMR spectrum of 10 two singlets at d 9.80
and d 9.88 were assigned to the COH and the COH0 pro-
characterized (see Section 3.2).
1
The H NMR spectra of 7 and 8 were similar to those
described for 3 and 4. A singlet at d 6.89 (7) and a doublet
at d 6.70 [3J(H4H3) = 8.0 Hz] (8) were assigned to the H3
resonance, shifted to lower frequency due to the shielding
effect of the diarsine phenyl rings, in agreement with a As
trans to N arrangement. This was confirmed by the formyl
group resonance in the spectrum of complex 7 (derived
from 1, R = 4-COH), shifted to lower frequency from the
starting material by 0.85 ppm.
1
tons. In the H NMR spectrum of 9 the resonances at d
9.43, upfield shifted due to the shielding effect of the phos-
phine phenyl rings, and at d 9.97, were ascribed to the
CHO and CHO0 protons, respectively. Two doublets of
doublets at d 7.06 and d 8.22 were assigned to H3 and
HC@N protons, respectively, and two doublets at d 7.21
and d 8.19 were assigned to H30 and HC ¼ N0, also
respectively.
Treatment of the chloro-bridged complexes 1 and 2 with
diphosphines or diarsines in a 1:2 molar ratio in the presence
of NH4PF6 and NaClO4 gave the mononuclear compounds
[Pd{RC6H3C(H)@NCy-C2,N}{(o-Tol)2P(CH2)2P(o-Tol)2-
P,P}][PF6] (R = 4-(COH), 11; R = 5-(COH), 12),
[Pd{RC6H3C(H)@NCy-C2, N}{Ph2PC4H2(NH)CH2PPh2-
In the 13C–{1H} NMR spectrum of 8 three singlets at d
170.5, d 166.0 and d 149.9 were assigned to the C@N, C1
and C2 carbons, downfield shifted from the spectrum of
the free ligand in agreement with metallation at C2. The
AsCH2 resonance was a singlet at d 29.7.
Reaction of 1 and 2 with the heterobidentate [P,N]
ligand Ph2P(CH2)2NH2 in 1:1 molar ratio gave the dinu-
clear complexes [{Pd[RC6H3C(H)@NCy-C2,N](Cl)}2-

4200
R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
R3
P
R
α
Ph2
As
R
R2
Pd
E
β
N
P
H
Pd
ClO4
R3
Cy
As
H
N
Ph2
Cy
11, R = 4-COH, R2 = (CH2)2, R3 = (o -Tol)2, E = PF6
12, R = 5-COH, R2 = (CH2)2, R3 = (o -Tol)2, E = PF6
13, R = 4-COH, R2 = C4H2(NH)CH2, R3 = Ph2, E = ClO4
14, R = 5-COH, R2 = C4H2(NH)CH2, R3 = Ph2, E = ClO4
15, R = 4-COH
16, R = 5-COH
ii
i
4
5
6
3
2
R
Cl
1
Pd
2
H
N
7
8
12
11
9
10
1, R = 4-COH
2, R = 5-COH
iii
v
O
H
iv
Ph2
Ph2
P
R
P
PF6
PF6
Pd
Pd
N
N
H
O
H
N
H
Cy
Me
Cy
Ph2
P
Me
R
R2
Pd
21, R = 4-COH
22, R = 5-COH
PF6
17
H
N
N
H2
Cy
18, R = 5-COH, R2 = (CH2)3
19, R = 4-COH, R2 = (CH2)2
20, R = 5-COH, R2 = (CH2)2
Scheme 2. (i) (o-Tol)2P(CH2)2P(o-Tol)2(1:2), NH4PF6, acetone/water (11,12); Ph2PC4H2(NH)CH2PPh2 (1:2), NaClO4, dichloromethane (13,14) (ii)
Ph2As(CH2)2AsPh2 (1:2), NaClO4, dichloromethane; (iii) Ph2P(CH2)2NH2 (1:2), NH4PF6, acetone/water. (iv) Ph2P(CH2)nNH2 (1:2), NH4PF6, toluene; (v)
Ph2P(C6H4)CHO (1:2), NH4PF6, acetone/water.
P, P}][ClO4] (R = 4-(COH), 13; R = 5-(COH), 14) and
[Pd{RC6H3C(H)@NCy-C2, N}{Ph2As(CH2)2AsPh2-As,
coupling constants, 4J(PaH3) = 4.4 Hz, 4J(PbH3) = 4.9 Hz.
However, the HC@N resonance appeared ca. d 8.40 as a
doublet by coupling to only the 31P nucleus trans to nitro-
gen. The 1H NMR spectra for compounds 11 and 12 showed
the COH and H3 resonances shifted to lower frequency
from the starting product due to the shielding effect of the
phosphine tolyl groups cis to carbon.
Reaction of 2 with Ph2P(CH2)3NH2 in 1:2 molar ratio
in acetone in the presence of NH4PF6 afforded [Pd{5-
(COH)C6H3C(H)@NCy-C2,N}{Ph2P(CH2)3N(@CMe2)-
P,N}][PF6] (17), with a chelating [P,N] ligand derived from
intermolecular condensation between the aminophosphine
and acetone. The IR spectrum showed two bands at 1621
and 1647 cmꢀ1 consistent with the presence of two different
imino groups, the HC@N group in the cyclometallated ring
and the Me2C@N group in the chelating [P,N] ligand after
As}][ClO4] (R = 4-(COH), 15; R = 5-(COH), 16). The con-
ductivity data (125–150 Xꢀ1 cm2 molꢀ1 in 10ꢀ3 mol dmꢀ3
solutions in dry acetonitrile) showed them to be 1:1 electro-
lytes [52]. The MS-FAB spectra showed, among others, the
corresponding peaks assigned to [M]+, [MꢀCOH]+ and/or
[MꢀCy]+ (see Section 3). The 31P–{1H} NMR spectra
showed two doublets, for the two non-equivalent phospho-
rus. The assignment of the doublets was made on the
assumption that a ligand of greater trans influence shifts
the resonance of the phosphorus atoms trans to it to lower
1
frequency [50]. In the H NMR spectrum a multiplet at d
6.55–6.90 was assigned to H3, coupled to both phosphorus
nuclei, e.g. for compound 14, selective decoupling experi-
ments allowed the correct assignment of the corresponding

R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
4201
condensation. The 31P–{1H} NMR spectra showed a sin-
agreement with oxygen coordination to the metal center.
The 31P–{1H} NMR spectra showed singlets at d 34.71
(21) and d 34.44 (22). The 1H NMR data was in agreement
with the P-trans-N and O-trans-C(phenyl ring) coordina-
tion. A doublet at d 10.15 was assigned to the CHO group
of the [P,O] ligand [4J(PH) = 1.5 Hz]. This signal was
upfield shifted 0.35 ppm from the spectrum of the free ligand
confirming oxygen coordination to the metal center, and
consistent with a r-bound aldehyde [53].
glet at d 28.61 in agreement with phosphorus coordination.
1
In the H NMR spectrum the shift of the HC@O and H3
resonances with respect to those of 2, were in accordance
with a P trans to N arrangement in the palladium environ-
ment. Furthermore, the spectrum showed the presence of
two singlets at d 2.30 and d 2.02 assignable to the non-
equivalent Me2C@N methyl groups.
Condensation of the NH2 group was precluded by change
of solvent. Thus, reaction of 1 and 2 with Ph2P(CH2)nNH2 in
toluene afforded compounds [Pd{RC6H3C(H)@NCy-C2,
N}{Ph2P(CH2)nNH2-P,N}][PF6] (n = 3, R = 5-(COH), 18;
n = 2, R = 4-(COH), 19; n = 2, R = 5-(COH), 20). The ana-
lytical and the mass data were in agreement with the pro-
posed structures. The conductivity measurements between
130 and 165 Xꢀ1 cm2 molꢀ1 in 10ꢀ3 mol dmꢀ3 solutions in
dry acetonitrile showed them to be 1:1 electrolytes, confirm-
ing the presence of the aminophosphine ligand in its neutral
form. The IR and NMR data were similar to that observed
for compound 17. No condensation of the phosphine amine
group to the (COH)C6H3-group was observed.
Treatment of 1 and 2 with Ph2P(C6H4)CHO in a
1:2 molar ratio in the presence of NH4PF6 gave the
mononuclear compounds [Pd{RC6H3C(H)@NCy-C2,N}-
{2-(Ph2P)C6H4CHO-P,O}][PF6] (R = 4-(COH), 21; R = 5-
(COH), 22) as 1:1 electrolytes with the ligand chelated to
the metal center to give a six-membered ring. The IR spec-
trum showed two bands ca. 1645 and 1695 cmꢀ1 consistent
with two different C@O groups. The former was shifted to
lower frequency as compared with the free [P,O] ligand in
2.1. Molecular structures of complexes 7, 11, 15 and 21
Suitable crystals were grown by slowly evaporating
dichloromethane/n-hexane (7,15,21) or chloroform/n-hex-
ane (11) solutions of the complexes. The labeling schemes
for the compounds are shown in Figs. 1–4.
All crystals consist of discrete molecules, separated by
normal van der Waals distances. Crystallographic data
and selected interatomic distances and angles are listed in
Tables 1 and 2.
For compound 7, the crystal structure comprises a dinu-
clear molecule (half molecule per asymmetric unit) and two
CH2Cl2 solvent molecule. The crystal structures of com-
pounds 11, 15 and 21 comprise a mononuclear cation
(one molecule per asymmetric unit), a perchlorate (15) or
a hexafluorophosphate (11,21) anion, 1.25CHCl3 for 11,
and half molecule of CH2Cl2 for 15.
In compound 7 the four-coordinated palladium(II) is
bonded to an adjacent ortho-carbon atom (C1) and to the
nitrogen atom of the imine group of the deprotonated
Fig. 1. Molecular structure of [{Pd[4-(COH)C6H3C(H)@NCy-C2,N](Cl)}2{l-Ph2As(CH2)2AsPh2}] (7), with labelling scheme. Hydrogen atoms have been
omitted for clarity.

4202
R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
Fig. 2. Molecular structure of the cation for [Pd{4-(COH)C6H3-
C(H)@NCy-C2,x N}{(o-Tol)2P(CH2)2P(o-Tol)2-P,P}][PF6] (11), with
labelling scheme. Hydrogen atoms have been omitted for clarity.
Fig. 4. Molecular structure of the cation for [Pd{4-(COH)C6H3-
C(H)@NCy-C2,N}{2-(Ph2P)C6H4CHO-P,O}][PF6] (21), with labelling
scheme. Hydrogen atoms have been omitted for clarifty.
atoms: and ortho-carbon of the phenyl ring and a nitrogen
atom of the benzylidene ligand, and the oxygen and phos-
phorous atoms of the 2-(diphenylphosphino)benzaldehyde
forming a six-membered ring chelate.
The sum of angles about palladium is approximately
360ꢁ as expected for a square-planar geometry. The angles
between adjacent atoms in the coordination sphere are
close to 90ꢁ; the most noticeable distortion corresponds
to the C(1)–Pd(1)–N(1) angle in the cyclometallated ring,
of 80.9(3)ꢁ (7), 80.7(3)ꢁ (11), 81.4(1)ꢁ (15), 81.6(1)ꢁ (21),
consequent upon chelation. The geometry around the pal-
ladium atom is slightly distorted square-planar, the mean
deviations from the least squares plane (plane 1: Pd1, C1,
N1, As1, Cl1, 7; Pd1, C1, N1, P1, P2, 11; Pd1, C1, N1,
As1, As2, 15; Pd1, C1, N1, P1, O2, 21;) are 0.1034,
˚
0.0959, 0.0771 and 0.0233 A, respectively.
˚
The palladium–carbon bond lengths, (2.004(7) A (7),
˚
˚
˚
2.080(8) A (11), 2.044(4) A (15), 1.996(3) A (21)), are
somewhat shorter than the expected value of 2.081 A (based
on the sum of the covalent radii for carbon(sp2) and palla-
dium, 0.771 and 1.31 A, respectively) [54]. However, the
palladium–nitrogen bond lengths in the metallacycle,
Fig. 3. Molecular structure of the cation for [Pd{4-(COH)C6H3-
C(H)@NCy-C2,N}{Ph2As(CH2)2AsPh2-As,As}][ClO4] (15), with labelling
scheme. Hydrogen atoms have been omitted for clarity.
˚
˚
˚
˚
(2.098(6) A (7), 2.113(7) A (11), 2.086(4) A (15), 2.087(2) A
(21)), are longer than the predicted single bond value of
2
˚
Schiff-base ligand and to a chlorine atom (trans to C1). An
arsenic atom from the diarsine ligand which bridges the
two metal centers, completes the metal coordination
sphere.
For mononuclear complexes 11 and 15 the palladium(II)
is bonded to the C1 and the nitrogen atoms of the Schiff-
base ligand and to the phosphorous (11) or arsenic (15)
atoms of the homobidentate chelating ligand. In com-
pound 21 the palladium(II) is bonded to four different
2.011 A (based on the sum of covalent radii for nitrogen(sp )
and palladium, 0.701 and 1.31 A, respectively), and reflects
˚
the influence of the atom in trans position. The Pd–P
˚
˚
(2.267(2) and 2.376(2) A (11), 2.2508(10) A (21)), Pd–As
(2.350(10) (7) and 2.359(5) and 2.4671(5) (15)) bond
distances, are shorter than the sum of the single bond radii
˚
for palladium and the corresponding atoms (2.41 A for
˚
Pd–P and 2.55 A for Pd–As), suggesting partial double bond
character similar to others reported earlier [23,55,56].

R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
4203
Table 1
Crystal and structure refinement data for complexes 7, 11, 15 and 21
7 Æ 2CH2Cl2 11 Æ 1.25CHCl3
56H60As2Cl6N2O2Pd2
15 Æ 0.5CH2Cl2
21
Formula
Mr
C
C45.25H49.25Cl3.75F6NOP3Pd
C40.5H42As2Cl2NO5Pd
949.89
293(2)
0.71073
Triclinic
C33H31F6NO2P2Pd
755.93
293(2)
0.71073
Monoclinic
P21/c
1368.4
293(2)
1069.35
293(2)
Temperature (K)
Wavelength (A)
Crystal system
Space group
˚
0.71073
Triclinic
0.71073
Monoclinic
C1c1
ꢀ
ꢀ
P1
P1
Cell dimensions
a (A)
b (A)
c (A)
a (ꢁ)
b (ꢁ)
c (ꢁ)
9.800(3)
13.343(4)
27.302(8)
14.721(4)
90
104.768(5)
90
12.655(10)
13.614(10)
13.888(10)
99.093(10)
116.113(10)
101.010(10)
16.405(5)
11.449(4)
18.108(6)
90
111.705(2)
90
12.853(4)
13.175(4)
101.536(6)
106.900(7)
112.224(6)
3
˚
V (A )
1377.0(7)
5185.6(26)
2027.8(3)
3159.9(18)
Z
1
4
2
4
Dcalc (Mg/m3)
1.445
2.180
1.370
0.698
1.556
2.252
1.589
0.756
l (mmꢀ1
)
Crystal size (mm)
2hmax (ꢁ)
0.29 · 0.07 · 0.05
56.72
0.44 · 0.21 · 0.20
56.98
0.34 · 0.30 · 0.17
56.54
0.36 · 0.11 · 0.10
56.74
Independent reflections
S
6285 (Rint = 0.0566)
0.948
5802 (Rint = 0.0327)
1.082
9197 (Rint = 0.0198)
1.018
7512 (Rint = 0.0459)
0.981
R [F, I > 2r(I)]
wR [F2, all data]
max q (e A )
0.0662
0.1404
0.880
0.0627
0.1849
1.131
0.0436
0.1209
1.061
0.0386
0.0861
0.403
3
˚
Absolute structure parameter
0.00(4)
Table 2
Selected bond distances (A) and angles (ꢁ) for complexes 7, 11, 15 and 21
11
7
15
21
Pd(1)–C(1)
Pd(1)–N(1)
Pd(1)–P(1)
Pd(1)–P(2)
2.004(7)
2.098(6)
2.080(8)
2.113(7)
2.267(2)
2.376(2)
2.044(4)
2.086(4)
1.996(3)
2.087(2)
2.2508(10)
Pd(1)–O(2)
2.106(2)
Pd(1)–Cl(1)
2.383(2)
Pd(1)–As(1)
Pd(1)–As(2)
C(1)–C(6)
C(6)–C(7)
N(1)–C(7)
O(1)–C(14)
2.350(10)
2.359(5)
2.4671(5)
1.393(6)
1.458(7)
1.284(6)
1.192(6)
81.4(15)
1.405(9)
1.443(9)
1.272(8)
1.201(8)
80.9(3)
1.414(13)
1.439(15)
1.276(11)
1.201(15)
80.7(3)
1.423(4)
1.447(4)
1.278(4)
1.212(3)
81.62(10)
100.02(8)
C(1)–Pd(1)–N(1)
C(1)–Pd(1)–P(1)
C(1)–Pd(1)–P(2)
C(1)–Pd(1)–As(1)
C(1)–Pd(1)–As(2)
C(1)–Pd(1)–O(2)
P(1)–Pd(1)–P(2)
As(1)–Pd(1)–As(2)
P(1)–Pd(1)–O(2)
As(1)–Pd(1)–Cl(1)
N(1)–Pd(1)–Cl(1)
N(1)–Pd(1)–P(1)
N(1)–Pd(1)–P(2)
N(1)–Pd(1)–As(1)
N(1)–Pd(1)–As(2)
N(1)–Pd(1)–O(2)
C(7)–N(1)–Pd(1)
N(1)–C(7)–C(6)
C(1)–C(6)–C(7)
C(6)–C(1)–Pd(1)
95.9(2)
171.6(2)
93.8(2)
97.2(12)
173.2(12)
171.67(10)
88.16(6)
84.6(8)
82.2(18)
90.6(6)
95.4(18)
175.2(2)
99.3(2)
177.5(10)
99.4(10)
90.24(9)
113.4(2)
117.3(3)
116.5(3)
111.2(2)
111.8(2)
119.7(6)
114.6(6)
112.5(5)
112.9(7)
118.6(9)
117.7(8)
109.1(6)
113.1(3)
117.7(4)
117.1(4)
110.7(3)

4204
R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
1
For compound 21 the Pd–O(2) bond distance,
200F spectrometer (200.0 MHz for H, 50.3 MHz for 13C–
{1H}, 81.0 MHz for 31P–{1H}). Conductivity measure-
ments were made on a Crison GLP 32 conductivimeter
using 10ꢀ3 M solutions in dry acetonitrile at room
temperature (298 K). The synthesis of [Pd{4-(COH)C6H3-
C(H)@NCy-C2,N}(l-Cl)]2 (1) and [Pd{5-(COH)C6H3-
C(H)@NCy-C2,N}(l-Cl)]2 (2) has been reported previously
from this laboratory [17,18]. The phosphine (o-
Tol)2P(CH2)2P(o-Tol)2 was prepared as described previ-
ously in the literature [61].
˚
˚
2.106(2) A, is longer than the expected value of 1.97 A
and shows the trans influence of the aryl carbon atom.
The distinct Pd–P and Pd–As bond distances in the
mononuclear compounds 11 and 15 also reflects the differ-
ing trans influence of the metallated carbon and the nitro-
gen atoms of the Schiff-base ligand (see Table 2).
˚
For compound 7 the Pd–Cl bond length, 2.383(2) A, is
consistent with Pd–Cl distances found in related species
[24,56] but longer than the sum of the covalent radii
˚
(2.30 A) also as a consequence of the trans influence of
the C(phenyl) carbon.
3.2. Syntheses
The mean deviations from the least squares planes deter-
mined for the metallacycle (plane 2: Pd1, C1, C6, C7, N1)
and the metallated phenyl ring (plane 3: C1, C2, C3, C4,
3.2.1. [{Pd[4-(COH)C6H3C(H)@NCy-C2,N](Cl)}2-
{l-(o-Tol)2P(CH2)2P(o-Tol)2}] (3)
˚
˚
C5, C6) are 0.0368 and 0.0063 A (7), 0.0472 and 0.0117 A
To a suspension of 1 (25.00 mg, 0.035 mmol) in dichloro-
methane (ca. 10 mL), (o-Tol)2P(CH2)2P(o-Tol)2 (13.57 mg,
0.032 mmol) was added. The mixture was stirred for 12 h
at room temperature, after which the precipitate formed
was filtered off, dried in vacuo, and recrystallized from chlo-
roform/n-hexane to yield the desired product as a yellow
solid.
˚
˚
(11), 0.0137 and 0.0052 A (15), 0.0115 and 0.0138 A (21),
respectively. The angle between these planes are as follows:
3.9ꢁ, 5.4ꢁ, 1.4ꢁ and 1.6ꢁ, also respectively. The angles
between plane 1 and the previous planes are: plane 1/plane
2: 8.0ꢁ(7), 8.1ꢁ(11), 5.9ꢁ(15), 1.6ꢁ(21) and plane 1/plane 3:
10.4ꢁ(7), 10.1ꢁ(11), 6.1ꢁ(15), 3.0ꢁ(21).
The crystal structure of 11 confirms that the bigger steric
requirement of the phosphine tolyl rings makes them to be
nearest of the H3 and the formyl group in the C4 position
of the metallated ring, with the consequences we have seen
Yield: 41%. Anal. Calc. for C58H64Cl2N2O2P2Pd2: C,
59.7; H, 5.5; N, 2.4. Found: C, 59.5; H, 5.1; N, 2.2%; IR:
m(C@N): 1621m, m(C@O): 1694 s. FAB-Mass: 775
[LPd(PP)]+, 291 [(L-CHO)Pd]+. 1H NMR: d = 4.58 (t,
CH2P, 2J(PH) = 10.8), 6.59 (br, H3), 7.07 (d, H5,
3J(H5H6) = 7.6 Hz), 9.04 (s, Ha). 31P–{1H} NMR:
d = 28.58 (s).
1
in the H NMR spectrum.
˚
In compound 21 the C(21)–O(2) distance (1.219(4) A) of
the aldehyde group is indicative of the greater double-bond
character typical of a r-bonded aldehyde group. This bond
length lies in the range reported for transition metal com-
plexes with aldehydes bonded in a r-fashion [57–59]. The
O(2) shows a displacement from the plane formed by the
phosphorous atom and the carbon atoms of the benzalde-
3.2.2. [{Pd[5-(COH)C6H3C(H)@NCy-C2,N](Cl)}2-
{l-(o-Tol)2P(CH2)2P(o-Tol)2}] (4)
To a suspension of 2 (25.00 mg, 0.035 mmol) in dichloro-
methane (ca. 10 mL), (o-Tol)2P(CH2)2P(o-Tol)2 (13.57 mg,
0.032 mmol) was added. The mixture was stirred for 12 h
at room temperature, after which the precipitate formed
was filtered off, dried in vacuo, and recrystallized from chlo-
roform/n-hexane to yield the desired product as a yellow
solid.
˚
hyde group (P(1), C(15)–C(21), r.m.s. = 0.0156 A) of
˚
0.24 A, which reflects the deviation from the planarity of
the aldehyde unit upon coordination to the metal center.
3. Experimental
Yield: 81%. Anal. Calc. for C58H64Cl2N2O2P2Pd2: C,
59.7; H, 5.5; N, 2.4. Found: C, 59.4; H, 5.2; N, 2.1%. IR:
m(C@N): 1614 m, m(C@O): 1693 s. FAB-Mass: 774
Caution (safety note): Perchlorate salts of metal com-
plexes with organic ligands are potentially explosive. Only
small amounts of these materials should be prepared and
handled with great caution.
1
2
[LPd(PP)]+. H NMR: d = 4.58 (t, CH2P, J(PH) = 10.8),
6.61 (br, H3), 7.10 (dd, H4, 3J(H6H4) = 1.7 Hz,
3J(H4H3) = 8.0 Hz), 9.81 (s, Ha). 31P–{1H} NMR:
d = 28.50 (s).
3.1. General remarks
All solvents were distilled prior to use from appropriate
drying agents [60]. Chemicals were used as supplied from
commercial sources. Elemental analyses (C,H,N) were car-
ried out in a Carlo-Erba 1108 elemental analyser. IR spectra
were recorded as KBr pellets or Nujol mulls on a Perkin–
Elmer 1330 spectrophotometer. Mass spectra were obtained
in a QUATRO mass spectrometer with Cs ion-gun and 3-
NBA matrix. NMR spectra were obtained as CDCl3 solu-
tions and referenced to SiMe4 (1H, 13C–{1H}) or 85%
H3PO4 (31P–{1H}); and were recorded on a Bruker AC-
3.2.3. [{Pd[4-(COH)C6H3C(H)@NCy-C2,N](Cl)}2(l-
Ph2PC4H2(NH)CH2PPh2)] (5)
Complex 5 was synthesized with a procedure similar to
that described for complex 3, but using Ph2PC4H2-
(NH)CH2PPh2.
Yield: 78%. Anal. Calc. forC57H57Cl2N3O2P2Pd2: C, 58.9;
H, 4.9; N, 3.6. Found: C, 58.5; H, 5.7; N, 3.5%. IR: m(C@N):
1619m, m(C@O): 1693s. FAB-Mass: 778 [LPd(PP)]+.
1H NMR: d = 6.54, 6.90 (d, H3, 4J(PH3) = 6.3, 5.4 Hz),
9.10, 9.33 (s, Ha). 13C NMR: d = 24.7 (s, C10), 25.5, 25.7

R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
4205
(s, C9, C11), 33.3, 33.6 (s, C8, C12), 62.0, 64.4 (s, C7), 124.0
(s, C6), 127.4 (s, C5), 129.0, 129.6 (d, Cm, 3J(PCm) =
11.3 Hz), 130.8, 131.2 (d, Cp, 4J(PCp) = 2.8, 2.1 Hz), 134.0,
Yield: 51%. Anal. Calc. for C42H48Cl2N3O2PPd2: C, 53.6;
H, 5.1; N, 4.5. Found: C, 53.4; H, 4.9; N, 4.1%. IR: m(C@N):
1616m, m(C@O): 1698s. FAB-Mass: 551 [LPd(PN)]+, 522
[(L-CHO)Pd(PN)]+, 291 [(L-CHO)Pd]+. 1H NMR:
2
134.8 (d, Co, J(PCo) = 13.5, 12.0 Hz), 135.8, 136.2 (d, C4,
4J(PC4) = 4.2, 4.3 Hz), 139.4, 139.8 (d, C3,3J(PC3) = 9.6,
d = 7.06 (dd, H3, J(H3H5) = 1.0 Hz, J(PH30) = 5.6 0Hz),
4
4
7.21 (d, H30, J(H30H5) = 1.0 Hz), 8.19 ðd;Hi ; 5JðHi H7Þ
4
9.8 Hz), 153.9, 154.3 (s, C2), 157.6 (s, C1), 170.6, 172.5 (d,
3
C@N, J(PC = N) = 2.8, 3.6 Hz), 191.8, 191.9 (s, COH).
¼ 1:0HzÞ, 8.22 (dd, Hi,5J(HiH7) = 1.0 Hz, 4J(PHi) =
31P–{1H} NMR: d = 39.08 (s), 41.36 (s).
7.3 Hz), 9.43, 9.97 ðs; Ha;Ha0Þ. 31P–{1H} NMR: d = 53.01
(s).
3.2.4. [{Pd[5-(COH)C6H3C(H)@NCy-C2,N](Cl)}2-
(l-Ph2PC4H2(NH)CH2PPh2)] (6)
3.2.8. [{Pd[5-(COH)C6H3C(H)@NCy-C2,N](Cl)}2-
{l-Ph2P(CH2)2NH2}] (10)
To a suspension of 2 (25.00 mg, 0.035 mmol) in chloro-
form (ca. 10 mL), Ph2PC4H2(NH)CH2PPh2 (13.38 mg,
0.032 mmol) was added. The mixture was stirred for 12 h
at room temperature, after which solvent was removed
under reduced pressure, and the residue triturated with
diethylether to yield a yellow solid, which was filtered off
and dried in vacuo.
Complex 10 was synthesized with a procedure similar to
that described for complex 4, but using acetone.
Yield: 25%. Anal. Calc. for C42H48Cl2N3O2PPd2: C, 53.6;
H, 5.1; N, 4.5. Found: C, 53.4; H, 5.2; N, 4.4%. IR: m(C@N):
1621m, m(C@O): 1688s. FAB-Mass: 551 [LPd(PN)]+, 522
[(L-CHO)Pd(PN)]+, 291 [(L-CHO)Pd]+. 1H NMR:
3
4
Yield: 59%. Anal. Calc. for C57H57Cl2N3O2P2Pd2(Et
2O)3: C, 62.0; H, 6.5; N, 3.1. Found: C, 61.9; H, 6.2; N,
3.1%. IR: m(C@N): 1620m, m(C@O): 1690s. FAB-Mass:
779 [(L-CHO)Pd(PP)]+, 291 [(L-CHO)Pd]+. 1H NMR:
d = 6.81 (dd, H3, J(H4H3) = 5.1 Hz, J(PH30) = 7.8 0Hz),
4
7.19 (dd, H4, J(H6H4) = 1.0 Hz), 7.99 ðd;Hi ; 5JðHi H7Þ
4
¼ 1:0HzÞ, 8.22 (d, Hi, J(PHi) = 8.8 Hz), 9.80, 9.88 (s,Ha,
Ha0). 31P–{1H} NMR: d = 53.01 (s).
4
d = 6.66, 6.95 (dd, H3, J(PH3) = 4.9, 5.8 Hz), 7.13 (dd,
H4, 4J(H4H6) = 1.6 Hz) 9.72, 9.79 (s, Ha). 31P–{1H}
NMR: d = 40.88 (s), 41.82 (s).
3.2.9. [Pd{4-(COH)C6H3C(H)@NCy-C2,N}{(o-Tol)2-
P(CH2)2P(o-Tol)2-P,P}][PF6] (11)
To a suspension of 1 (20.00 mg, 0.028 mmol) in acetone
3.2.5. [{Pd[4-(COH)C6H3C(H)@NCy-C2,N](Cl)}2-
{l-Ph2As(CH2)2AsPh2}] (7)
Complex 7 was synthesized with a procedure similar to
that described for complex 3, but using Ph2As(CH2)2-
AsPh2.
Yield: 79%. Anal. Calc. for C54H56As2Cl2N2O2Pd2: C,
54.1; H, 4.7; N, 2.3. Found: C, 54.2; H, 4.6; N, 2.1%. IR:
m(C@N): 1620 m, m(C@O): 1693s. FAB-Mass: 807 [LPd(As-
As)]+, 291 [(L-CHO)Pd]+. 1H NMR: d = 4.48 (m, CH2As),
6.89 (s, H3), 8.12 (d, Hi, 5J(HiH7) = 1.0 Hz), 9.13 (s, Ha).
(ca.
15 mL),
(o-Tol)2P(CH2)2P(o-Tol)2
(23.77 mg,
0.056 mmol) was added. The mixture was stirred for 2 h
at room temperature, after which ammonium hexafluoro-
phosphate in estequiometric amount was added, the resul-
tant solution stirred for a further 1 h, water (ca. 40 mL)
was added dropwise and the resulting mixture stirred for
2 h. A precipitate formed was filtered off, washed with
water (2 · 5 mL) and dried in vacuo. The desired complex
was recrystallized from chloroform/n-hexane.
Yield: 82%. Anal. Calc. for C44H48F6NOP3Pd: C, 57.4; H,
5.2; N, 1.5. Found: C, 57.2; H, 4.7; N, 1.4%. IR: m(C@N):
1616 m, m(C@O): 1695s. FAB-Mass: 773[M]+, 291 [(L-
CHO)Pd]+. 1H NMR: d = 6.90 (m, H3, 3J(H3H5) = 2.1 Hz,
4J(PaH3) = 4.4 Hz, 4J(PbH3) = 4.9 Hz), 7.65 (dd, H5,
3.2.6. [{Pd[5-(COH)C6H3C(H)@NCy-C2,N](Cl)}2-
{l-Ph2As(CH2)2AsPh2}] (8)
Complex 8 was synthesized with a procedure similar to
that described for complex 4, but using Ph2As(CH2)2-
AsPh2.
3J(H5H6) = 7.5 Hz), 8.50 (d, Hi, J(PaHi) = 7.8 Hz), 9.26
4
(s, Ha). 31P–{1H} NMR: d = 42.01 (d, Pb, 3J(PP) = 2.2 Hz),
Yield: 90%. Anal. Calc. for C54H56As2Cl2N2O2Pd2: C,
54.1; H, 4.7; N, 2.3. Found: C, 53.9; H, 5.0; N, 2.2%. IR:
m(C@N): 1624m,m(C@O): 1693s. FAB-Mass: 807 [LPd(A-
sAs)]+. 1H NMR: d = 4.48 (m, CH2As), 6.70 (d, H3,
3J(H4H3) = 8.0 Hz), 7.00 (dd, H4, 6J(H6H4) = 1.9 Hz),
8.17 (s, Hi), 9.75 (s, Ha). 13C NMR: d = 29.7 (s, CH2As),
25.4 (s, C9, C11), 25.7 (s, C10), 33.5 (s, C8, C12), 62.8 (s,
C7), 126.8 (s, C6), 128.8 (s, Cm), 131.1 (s, Cp), 133.4 (s,
Co), 138.1 (s, C3), 149.9 (s C2), 166.0 (s, C1), 170.5 (s,
C@N), 191.2 (s, COH).
56.15 (d, Pa).
3.2.10. [Pd{5-(COH)C6H3C(H)@NCy-C2,N}-
{(o-Tol)2P(CH2)2P(o-Tol)2-P,P}][PF6] (12)
Compound 12 was synthesized following a procedure
similar to that described for 11, but using 2 as a starting
material.
Yield: 76%. Anal. Calc. for C44H48F6NOP3Pd: C, 57.4;
H, 5.2; N, 1.5. Found: C, 57.7; H, 5.2; N, 1.3%. R:
m(C@N): 1619m, m(C@O): 1690m. FAB-Mass: 773 [M]+,
690 [MꢀCy]+, 291 [(L-CHO)Pd]+. 1H NMR: d = 3.73
3
3.2.7. [{Pd[4-(COH)C6H3C(H)@NCy-C2,N](Cl)}2{l-
Ph2P(CH2)2NH2}] (9)
Complex 9 was synthesized with a procedure similar to
that described for complex 3, but using acetone.
(dd, CH2P), 6.70 (m, H3, J(H4H3) = 8.3 Hz), 7.18 (dd,
H4, 4J(H6H4) = 1.8 Hz), 7.94 (b, H6), 8.49 (d, Hi,
4J(PaHi) = 8.3 Hz), 9.83 (s, Ha). 31P–{1H} NMR:
3
d = 42.62 (d, Pb, J(PP) = 15.3 Hz), 56.45 (d, Pa).

4206
R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
3.2.11. [Pd{4-(COH)C6H3C(H)@NCy-C2,N}{Ph2PC4H2
(NH)CH2PPh2-P,P}][ClO4] (13)
C4), 130.1 (s, Cm), 132.0 (s, Cp), 133.1 (s, Co), 138.6 (s,
C3), 155.7 (s, C1), 174.3 (s C2), 176.2 (s, C@N), 191.2 (s,
COH).
To a suspension of 1 (20.00 mg, 0.028 mmol) in dichloro-
methane (ca. 15 mL), Ph2PC4H2(NH)CH2PPh2 (25.40 mg,
0.056 mmol) was added. The mixture was stirred for 2 h at
room temperature, after which estequiometric amount of
sodium perchlorate was added, the resultant solution stirred
for a further 1 h. Then the solvent was removed under
reduced pressure, and the residue triturated with hexane to
yield a solid, which was filtered off and dried in vacuo. The
desired complex was recrystallized from chloroform/n-hex-
ane as yellow microcrystals.
3.2.15. [Pd{5-(COH)C6H3C(H)@NCy-C2,N}-
{Ph2P(CH2)3N(@CMe2)-P,N}][PF6] (17)
Compound 17 was synthesized following a procedure
similar to that described for 11, but using 2 and
Ph2P(CH2)3NH2 as starting materials.
Yield: 29%. Anal. Calc. for C32H38F6N2OP2Pd: C, 52.1;
H, 5.5; N, 3.5. Found: C, 52.5; H, 5.4; N, 3.7FAB-Mass:
604 [M]+, 291 [(L-CHO)Pd]+. 1H NMR: d = 2.30, 2.02
3
Yield: 73%. Anal. Calc. for C43H41ClN2O5P2Pd: C, 59.4;
H, 4.7; N, 3.2. Found: C, 59.2; H, 4.8; N, 3.0%. IR:
m(C@N): 1618m, m(C@O): 1691m. FAB-Mass: 769 [M]+,
291 [(L-CHO)Pd]+. 1H NMR: d = 6.70 (dd, H3,
4J(H3H5) = 1.2 Hz, 4J(PaH3) = 4.4 Hz), 8.41 (d, Hi,
4J(PaHi) = 7.8 Hz), 9.30 (s, Ha). 31P–{1H} NMR:
(s, Me), 6.44 (m, H3, J(H4H3) = 7.8 Hz), 7.11 (dd, H4,
4
4J(H6H4) = 1.5 Hz), 8.64 (d, Hi, J(PHi) = 7.3 Hz), 9.81
(s, Ha). 31P–{1H} NMR: d = 28.61 (s).
3.2.16. [Pd{5-(COH)C6H3C(H)@NCy-C2,N}-
{Ph2P(CH2)3NH2-P,N}][PF6] (18)
Compound 18 was synthesized following a procedure
similar to that described for 11, but using 2 and
Ph2P(CH2)3NH2 as starting materials, and toluene as
solvent.
5
d = 7.71 (d, Pb, J(PP) = 114.4 Hz), 36.93 (d, Pa).
3.2.12. [Pd{5-(COH)C6H3C(H)@NCy-C2,N}{Ph2PC4H2
(NH)CH2PPh2-P, P}][ClO4] (14)
Compound 14 was synthesized following a procedure
similar to that described for 13, but using 2 as a starting
material.
Yield: 56%. Anal. Calc. for C29H34F6N2OP2Pd: C, 49.2;
H, 4.8; N, 4.0. Found: C, 49.0; H, 4.6; N, 4.1%. IR:
m(C@N): 1618m, m(C@O): 1697m. FAB-Mass: 563 [M]+,
562 [MꢀCHOꢀCy]+, 291 [(L-CHO)Pd]+. 1H NMR:
Yield: 65%. Anal. Calc. for C43H41ClN2O5P2Pd: C, 59.4;
H, 4.7; N, 3.2. Found: C, 59.2; H, 4.9; N, 3.1%. IR: m(C@N):
1618m, m(C@O): 1695m. FAB-Mass: 769 [M]+, 687
3
4
d = 6.57 (dd, H3, J(H4H3) = 7.9 Hz, J(PH3) = 5.8 Hz),
8.31 (d, Hi, 4J(PHi) = 7.6 Hz), 9.80 (s, Ha). 31P–{1H}
NMR: d = 21.77 (s).
1
[MꢀCy]+, 291 [(L-CHO)Pd]+. H NMR: d = 6.55 (m, H3,
3J(H4H3) = 7.8 Hz,4J(PaH3) = 4.4 Hz,
4J(PbH3) = 4.9
4
Hz), 7.12 (dd, H3, J(H6H4) = 2.0 Hz), 7.80 (d, H6), 8.42
3.2.17. [Pd{4-(COH)C6H3C(H)@NCy-C2,N}-
{Ph2P(CH2)2NH2-P,N}][PF6] (19)
Compound 19 was synthesized following a procedure
similar to that described for 11, but using Ph2P(CH2)2NH2
as starting material, and toluene as solvent.
4
(d, Hi, J(PaHi) = 4.9 Hz), 9.81 (s, Ha). 31P–{1H} NMR:
d = 6.67 (d, Pb, 3J(PP) = 107.6 Hz), 37.24 (d, Pa).
3.2.13. [Pd{4-(COH)C6H3C(H)@NCy-C2,N}-
{Ph2As(CH2)2AsPh2-As,As}][ClO4] (15)
Compound 15 was synthesized following a procedure
similar to that described for 13, but using Ph2As(CH2)2
AsPh2 as a starting material.
Yield: 54%. Anal. Calc. for C40H40As2ClNO5Pd: C,
53.0; H, 4.5; N, 1.6. Found: C, 53.2; H, 4.4; N, 1.3%. IR:
m(C@N): 1615m, m(C@O): 1692s. FAB-Mass: 807 [M]+,
768 [MꢀCHO]+. 1H NMR: d = 7.74 (d, H5, 3J(H5H6)
= 7.8 Hz), 8.54 (s, Hi), 9.44 (s, Ha).
Yield: 34%. Anal. Calc. for C28H32F6N2OP2Pd: C, 48.4;
H, 4.6; N, 4.0. Found: C, 48.5; H, 4.1; N, 4.0%. IR:
m(C@N): 1616m, m(C@O): 1692f. FAB-Mass: 549 [M]+,
1
520 [MꢀCHO]+. H NMR: d = 6.76 (d, H3, 4J(H3H5)
= 1.2 Hz, 4J(PH3) = 5.4 Hz), 7.18 (dd, H5, 3J(H5H6) =
5.1 Hz,), 8.69 (dd, Hi, 4J(PHi) = 7.8 Hz, 5J(HiH7) =
1.0 Hz), 9.51 (s, Ha). 13C NMR: d = 25.1 (s, C9, C11),
25.4 (s, C10), 33.5 (s, C8, C12), 67.3 (s, C7), 126.4 (s, Ci,
1J(PCi) = 51.3 Hz), 128.7 (s, C6) 129.1 (s, C5), 129.6 (d,
3
4
Cm, J(PCm) = 11.4 Hz), 132.6 (d, Cp, J(PCp) = 2.8 Hz),
2
4
3.2.14. [Pd{5-(COH)C6H3C(H)@NCy-C2, N}-
{Ph2As(CH2)2AsPh2-As,As}][ClO4] (16)
Compound 16 was synthesized following a procedure
similar to that described for 13, but using 2 and
Ph2As(CH2)2AsPh2 as starting materials.
134.1(d, Co, J(PCo) = 12.1 Hz), 136.6 (d, C4, J(PC4) =
4.5 Hz), 138.4 (d, C3, 3J(PC3) = 11.1 Hz), 153.8 (s,
C1),156.8 (d, C2, 2J(PC2) = 2.1 Hz), 177.6 (d, C@N,
3J(PC = N) = 6.4 Hz), 191.5 (s, COH). 31P–{1H} NMR:
d = 54.20 (s).
Yield: 53%. Anal. Calc. for C40H40As2ClNO5Pd: C,
53.0; H, 4.4; N, 1.6. Found: C, 53.1; H, 4.3; N, 1.6%. IR:
m(C@N): 1624m, m(C@O): 1696m. FAB-Mass: 807 [M]+.
3.2.18. [Pd{5-(COH)C6H3C(H)@NCy-C2,N}-
{Ph2P(CH2)2NH2-P,N}][PF6] (20)
Compound 20 was synthesized following a procedure
similar to that described for 11, but using 2 and
Ph2P(CH2)2NH2 as starting material, and toluene as
solvent.
3
1H NMR: d = 7.04 (d, H3, J(H4H3) = 8.3 Hz), 8.00 (s,
H6), 8.47 (s, Hi), 9.85 (s, Ha). 13C NMR: d = 24.8 (s,
C10), 25.0 (s, C9, C11), 29.7 (s, CH2As), 33.7 (s, C8,
C12), 63.5 (s, C7), 128.4 (s, Ci), 128.5 (s, C6), 129.6 (s,

R. Ares et al. / Journal of Organometallic Chemistry 692 (2007) 4197–4208
4207
Yield: 19%. Anal. Calc. for C28H32F6N2OP2Pd: C, 48.4;
4. Supplementary material
H, 4.6; N, 4.0. Found: C, 49.1; H, 4.3; N, 4.0%. IR:
m(C@N): 1621 m, m(C@O): 1688m. FAB-Mass: 549 [M]+,
CCDC 634450, 634447, 634448 and 634449 contain the
supplementary crystallographic data for 7, 11, 15 and 21.
These data can be obtained free of charge via http://
www.ccdc.cam.ac.uk/conts/retrieving.html, or from the
Cambridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: (+44) 1223-336-033; or e-
mail: deposit@ccdc.cam.ac.uk.
1
520 [MꢀCHO]+, 291 [(L-CHO)Pd]+. H NMR: d = 6.79
3
4
(dd, H3, J(H4H3) = 7.8 Hz, J(PH3) = 5.4 Hz), 7.20 (dd,
H4, 4J(H6H4) = 1.7 Hz), 8.28 (d, Hi, 4J(PHi) = 7.8 Hz),
9.80 (s, Ha). 31P–{1H} NMR: d = 21.77 (s).
3.2.19. [Pd{4-(COH)C6H3C(H)@NCy-C2,N}{2-(Ph2P)-
C6H4CHO-P,O}][PF6] (21)
Compound 21 was synthesized following a procedure
similar to that described for 11, but using Ph2-
P(C6H4)CHO.
Acknowledgements
´
We thank the Ministerio de Educacion y Ciencia (Pro-
ject CTQ2006-15621-C02-01/BQU) and the Xunta de Gali-
cia (Ref. PGIDIT04PXI10301IF) for financial support.
Yield:57%. Anal. Calc.forC33H31F6NO2P2Pd Æ (Me2CO ):
C, 53.1; H, 4.6; N, 1.7. Found: C, 53.4; H, 4.4; N, 1.7%. IR:
m(C@N): 1624 m, m(C@O): 1645m, 1695m. FAB-Mass: 611
1
4
[M]+. H NMR: d = 6.68 (d, H3, J(PH3) = 5.9 Hz), 8.27
(dd, Hi, 4J(PHi) = 8.3 Hz, 5J(HiH7) = 1.0 Hz), 9.32 (s,
Ha), 10.15 (d, PCHO, 4J(PCHO) = 1.5 Hz). 31P–{1H}
NMR: d = 34.71 (s).
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