Mono- and bimetallic complexes of the group 10 metals with N-heteroaryl phosphine ligands

Article abstract of DOI:10.1016/j.jorganchem.2014.02.003

Reaction of the recently synthesized ligands N-(diphenylphosphino)-4- (pyridin-2-yl)pyrimidin-2-amine (Hpypya) and N-(diphenylphosphino)-4- phenylpyrimidin-2-amine (Hphpya) with [M(COD)Cl₂] (M = Pd, Pt) (COD = 1,5-cyclooctadiene) in hot DMSO resulted in the corresponding palladium and platinum complexes [(Hpypya)MCl₂] (M = Pd (1), Pt (2)) and [(Hphpya)MCl₂] (M = Pd (3), Pt (4)). All compounds were characterized by single crystal X-ray diffraction. In all compounds the metal atom is distorted square planar coordinated. The N-H function forms hydrogen bonds either to a polar solvent molecule or to another metal complex. Further reaction of the pyridyl derivative [(Hpypya)PdCl₂] with [AuCl(tht)] (tht = tetrahydrothiophene) did not result in a bimetallic neutral complex but in the ionic bimetallic compound [(Hpypya)PdCl][AuCl₂] (5). Due to the addition of [AuCl(tht)] the gold(I) ion abstracts one chlorine atom from the palladium atom to form a linear [AuCl₂]^- anion. To keep the preferred square planar coordination mode of the palladium ion the remaining [(Hpypya)PdCl]⁺ cation rearranges in such a way that the Hpypya ligand binds in a tridendate N,N′,P coordination mode.

Full text of DOI:10.1016/j.jorganchem.2014.02.003

Journal of Organometallic Chemistry 758 (2014) 29e35
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Mono- and bimetallic complexes of the group 10 metals with
N-heteroaryl phosphine ligands
Christian Sarcher a, Saeid Farsadpour b, Leila Taghizadeh Ghoochany b, Yu Sun b,
**
,
a,
*
Werner R. Thiel b , Peter W. Roesky
a Institut für Anorganische Chemie, Karlsruher Institut für Technologie (KIT), Engesserstraße 15, Geb. 30.45, 76131 Karlsruhe, Germany
b Fachbereich Chemie, TU Kaiserslautern, Erwin-Schrödinger-Str. 54, 67663 Kaiserslautern, Germany
a r t i c l e i n f o
a b s t r a c t
Article history:
Reaction of the recently synthesized ligands N-(diphenylphosphino)-4-(pyridin-2-yl)pyrimidin-2-amine
(Hpypya) and N-(diphenylphosphino)-4-phenylpyrimidin-2-amine (Hphpya) with [M(COD)Cl2] (M ¼ Pd,
Pt) (COD ¼ 1,5-cyclooctadiene) in hot DMSO resulted in the corresponding palladium and platinum
complexes [(Hpypya)MCl2] (M ¼ Pd (1), Pt (2)) and [(Hphpya)MCl2] (M ¼ Pd (3), Pt (4)). All compounds
were characterized by single crystal X-ray diffraction. In all compounds the metal atom is distorted
square planar coordinated. The NeH function forms hydrogen bonds either to a polar solvent molecule or
to another metal complex. Further reaction of the pyridyl derivative [(Hpypya)PdCl2] with [AuCl(tht)]
(tht ¼ tetrahydrothiophene) did not result in a bimetallic neutral complex but in the ionic bimetallic
compound [(Hpypya)PdCl][AuCl2] (5). Due to the addition of [AuCl(tht)] the gold(I) ion abstracts one
chlorine atom from the palladium atom to form a linear [AuCl2]ꢀ anion. To keep the preferred square
planar coordination mode of the palladium ion the remaining [(Hpypya)PdCl]þ cation rearranges in such
a way that the Hpypya ligand binds in a tridendate N,N0,P coordination mode.
Received 10 December 2013
Received in revised form
29 January 2014
Accepted 3 February 2014
Keywords:
Chelates
Multimetallic compounds
Palladium
Platinum
P,N ligands
Ó 2014 Elsevier B.V. All rights reserved.
1. Introduction
expected [26]. In case of NeH functions being present on the ligand
scaffold, the formation of intramolecular hydrogen bonds may also
Chelating ligands with phosphorus and nitrogen donor atoms
are well established in organometallic chemistry [1]. They also play
an important role in homogeneous catalysis [2e5]. These ligands
can be modified in terms of the electronic and steric properties, as
well as of the bite angle. Besides the influence of the modification
on the coordination properties of the ligands, the rate and selec-
tivity of a catalytic reaction can also be influenced [6].
result in dimeric or polymeric structures.
Herein we report our results on reactions of the recently syn-
thesized
ligands
N-(diphenylphosphino)-4-(pyridin-2-yl)pyr-
imidin-2-amine (Hpypya) and N-(diphenylphosphino)-4-pheny
lpyrimidin-2-amine (Hphpya) with suitable palladium and plat-
inum precursors giving new group 10 complexes.
Chelating P,N ligands are a well-established class of compounds
in group 10 chemistry [7e21]. In this context some of us are
working for some time on phosphine ligands having an aromatic N-
heterocycle bound to the phosphorus centre [22e25]. The N-het-
erocycle decreases the electron-density at the phosphorus atom.
For square planar coordinate group 8 complexes these compounds
may act as chelating ligands coordinating via the P and one N atom
to the metal site [22] while in gold(I) chemistry mainly linear co-
ordination of the gold atom to the phosphine function will be
2. Results and discussion
Reaction of Hpypya with [M(COD)Cl2] (M ¼ Pd, Pt) (COD ¼ 1,5-
cyclooctadiene) in hot DMSO resulted in the palladium and plat-
inum complexes [(Hpypya)MCl2] (M ¼ Pd (1), Pt (2)) (Scheme 1). In
a similar way the corresponding phenyl functionalized Hphpya
complexes [(Hphpya)MCl2] (M ¼ Pd (3), Pt (4)) were obtained
(Scheme 1). All four new compounds have been characterized by
standard analytical/spectroscopic techniques and their solid-state
structures were established by single crystal X-ray diffraction.
The 1H NMR spectra of all compounds show not very charac-
teristic signals in the aromatic region and one broad peak at lower
field for the NeH function. In contrast the 31P{1H} NMR spectra of
1e4 show a very characteristic signal which is down-field shifted in
* Corresponding author. Tel.: þ49 721 6084 6117; fax: þ49 721 6084 4854.
** Corresponding author.
E-mail address: roesky@kit.edu (P.W. Roesky).
http://dx.doi.org/10.1016/j.jorganchem.2014.02.003
0022-328X/Ó 2014 Elsevier B.V. All rights reserved.

30
C. Sarcher et al. / Journal of Organometallic Chemistry 758 (2014) 29e35
Scheme 1. Synthesis of 1e4.
comparison to the non-coordinated ligands (Table 1). In general the
shift is larger for the palladium complexes 1 and 3 (about 30e
coordinated phosphorous and nitrogen atoms. Crystallizing 2 by a
slow diffusion of n-pentane into a concentrated solution of 2 in
CH2Cl2 resulted in a different solid state structure. In this case
compound 2 crystallizes in the triclinic space group P-1 with two
molecules of 2 and one equivalent of DMSO in the asymmetric unit
(Fig. 3). The DMSO molecule again coordinates via a hydrogen bond
to the amino function (N1eH1). 2 dimerizes via a hydrogen bond
between the nitrogen atom (N4) of the pyridine ring and the amino
function (N5eH5A) of the second equivalent. The bonding
parameters are in both independent molecules similar and
will thus only be discussed for one molecule. As observed for 1 the
32 ppm) than for the platinum compounds 2 and 4 (about 6e
1
12 ppm). Moreover, characteristic satellite signals of the JPtP
-
coupling (3817 Hz (2), 3838 Hz (4)) are present in the 31P{1H} NMR
spectra. This coupling is also detected in the 195Pt NMR spectra of 2
and 4 which shows the expected doublets at
d
¼ ꢀ3526 ppm (2)
and ꢀ3538 ppm (4). There is no hint for a second coordination
isomer with the other N atom acting as a donor site in the NMR
spectra. Furthermore Hpypya does not undergo bidentate N,N or
tridentate P,N,N coordination under the given reaction conditions.
Single crystals of compounds 1e4 were obtained from hot
DMSO. Single crystals of 2 were also grown by a slow diffusion of n-
pentane into a concentrated solution of 2 in CH2Cl2. By using the
latter method a lower amount of DMSO is co-crystallized in the unit
cell. Compound 1 crystallizes in the monoclinic space group P21/n
with four molecules of 1 and two molecules of DMSO in the unit cell
(Fig.1). One of those DMSO molecules is bound via a hydrogen bond
to the amino function of 1. All hydrogen atoms of 1 but not those of
the DMSO molecules could be localized in the difference Fourier
map. As expected the palladium atom is distorted square planar
coordinated by the Hpypya ligand and two chlorine atoms. All bond
angles around palladium vary from 83.56(6)ꢁ to 93.71(6)ꢁ and thus
are close to the expected ideal 90ꢁ bond angle. As a result of the
coordination of the Hpypya ligand a five membered PdePeNeCeN
metallacycle is formed. The two PdeCl bond distances vary signif-
ꢀ
Pt1eCl bond distances differ (Pt1eCl1 2.294(2) A and Pt1eCl2
ꢀ
2.370(2) A) as a result of the trans influence of the ligand. They are
ꢀ
in the range of [(dppai)(PtCl2)] (PteCl1 2.3381(11) A, PteCl2
ꢀ
ꢀ
ꢀ
2.3068(11) A, PteN 2.039(3) A, PteP 2.1998(11) A) [28]. As expected
the platinum atom is square planar coordinated with a bite angle of
the ligand of N2ePt1eP1 83.7(2)ꢁ.
ꢀ
ꢀ
icantly (PdeCl1 2.3864(10) A, PdeCl2 2.2895(9) A). This difference
can be explained by the trans influence of the opposite coordinated
ꢀ
phosphorous and nitrogen atoms. The PdeP-distance is 2.1962(9) A
and the PdeN2 bond length is 2.057(2) A. Similar bond distances
ꢀ
were observed in [(dppai)(PdCl2)] (dppai ¼ Diphenyphosphino-7-
ꢀ
ꢀ
azaindol) (PdeCl1 2.3444(6) A, PdeCl2 2.2875(7) A, PdeP
ꢀ
ꢀ
2.2144(6) A, PdeN 2.044(2) A) [27].
The analogue platinum compound 2 crystallizes from hot DMSO
in an isostructural setup as 1 with a distorted square planar coor-
dinated platinum atom (Fig. 2). As observed for 1 the two PteCl
ꢀ
bond distances vary significantly (PteCl1 2.3809(12) A, PteCl2
ꢀ
2.2938(12) A) as a result of the trans influence of the opposite
Table 1
ꢀ
31P{1H} NMR data of 1e4 in comparison to the non-coordinated ligand.
Fig. 1. Solid-state structure of 1, omitting hydrogen atoms. Selected bond lengths [A]
and angles [ꢁ]: PdeCl1 2.3864(10), PdeCl2 2.2895(9), PdeP 2.1962(9), PdeN2 2.057(2),
PeN1 1.678(2), PeC1 1.813(2), PeC7 1.807(2), N1eH1 0.78(3), O1eH1 1.94(4), N1eO1
2.715(3); Cl1ePdeCl2 93.58(3), Cl2ePdeP 89.28(3), PePdeN2 83.56(6), N2ePdeCl1
93.71(6), Cl1ePdeP 176.05(2), Cl2ePdeN2 172.35(6), PdePeN1 100.89(8), PdePeC1
115.44(8), PdePeC7 123.78(9), PdeN2eC13 117.88(15), N1ePeC1 107.06(11), N1ePe
C7 104.50(12), C1ePeC7 103.62(11), N1eC13eN2 117.1(2) N1eH1eO1 176(4).
Non-coordinated ligand
31P{1H}) [ppm]
[(L)PdCl2]
31P{1H}) [ppm]
[(L)PtCl2]
d (
31P{1H}) [ppm]
d
(
d
(
Hpypya
Hphpya
29.7
24.7
72.0
64.3
36.2
36.1

C. Sarcher et al. / Journal of Organometallic Chemistry 758 (2014) 29e35
31
Fig. 4. Solid-state structure of 3, omitting carbon bound hydrogen atoms. Selected
ꢁ
ꢀ
bond lengths [A] and angles [ ]: PdeCl1 2.3594(8), PdeCl2 2.2976(7), PdeP 2.1925(8),
PdeN2 2.043(2), PeN1 1.684(2), PeC1 1.805(2), PeC7 1.803(2) N1eH1 0.79(3), OeH1
1.96(3), N1eO 2.751(3); Cl1ePdeCl2 93.08(3), Cl2ePdeP 89.11(3), PePdeN2 83.71(5),
N2ePdeCl1 94.25(6), Cl1ePdeP 174.76(2), Cl2ePdeN2 172.53(5), PdePeN1 100.90(7),
PdePeC1 115.41(8), PdePeC7 119.75(8), PdeN2eC13 118.26(14), N1ePeC1 106.57(11),
N1ePeC7 106.88(10), C1ePeC7 106.18(11), N1eC13eN2 117.0(2), N1eH1eO 173(3).
Fig. 2. Solid-state structure of 2 (monoclinic) omitting hydrogen atoms. Selected bond
ꢁ
ꢀ
lengths [A] and angles [ ]: PteCl1 2.3809(12), PteCl2 2.2938(12), PteP 2.1878(12), Pde
N2 2.040(3), PeN1 1.674(3), PeC1 1.817(4), PeC7 1.811(4), N1eO1 2.723(4); Cl1ePte
Cl2 90.92(4), Cl2ePteP 92.21(4), PePteN2 84.01(9), N2ePteCl1 92.95(9), Cl1ePteP
176.13(4), Cl2ePteN2 175.60(9), PtePeN1 100.89(12), PtePeC1 116.30(14), PtePeC7
123.28(15), PteN2eC13 117.7(3), N1ePeC1 106.8(2), N1ePeC7 104.6(2), C1ePeC7
103.3(2), N1eC13eN2 117.1(4).
(4). As expected for both compounds a slightly distorted square
planar arrangement of the ligands around the metal centre is
observed.
Since the Hpypya ligand of 1 and 2 has a non-coordinating ni-
trogen atom in the pyridyl ring we desired to synthesize some
heterobimetallic complexes by adding another metal source. Re-
action of 1 with [AuCl(tht)] (tht ¼ tetrahydrothiophene) did not
result in a bimetallic neutral complex but in the ionic compound
[(Hpypya)PdCl][AuCl2] (5) (Scheme 2). Due to the addition of
[AuCl(tht)] the gold(I) ion abstracts one chlorido ligand from the
palladium site to form a linear [AuCl2]ꢀ anion. To keep the preferred
square planar coordination mode of the palladium ion the
remaining [(Hpypya)PdCl]þ cation rearranges in such a way that the
Hpypya ligand now binds in a tridendate N,N0,P coordination mode.
In the 1H NMR spectrum the expected set of signals are observed
in the aromatic region. Additionally the NH signal is seen at low
Compounds 3 and 4 which crystallize in the monoclinic space
group P21/c with one complex molecule and one molecule of DMSO
in the asymmetric unit are isostructural to each other (Figs. 3
and 4). As observed for 1 the DMSO molecule is bound via a
hydrogen bond (N1eH1eO) to the NeH function of the Hphpya
ligand. In contrast to 1 and 2 only the pyridine ring is substituted by
a phenyl group in 3 and 4. Since this group is remote from the metal
centre it does not significantly influence the coordination of the
Hphpya ligand in comparison to Hpypya. The bite angle of the
Hphpya ligand is PePdeN2 83.71(2)ꢁ (3) and PePteN2 83.85(13)ꢁ
field (
More characteristic is the 31P{1H} NMR spectrum which shows one
peak at
d
¼ 9.04 ppm) in a comparable range to 1 (
d
¼ 9.06 ppm).
d
¼ 71.2 ppm. This signal is down field shifted by almost
40 ppm in comparison to the non-coordinated ligand. In the ESI-MS
spectrum the peak at m/z ¼ 499.00 amu can be assigned to the
[(Hpypya)PdCl]þ cation.
Single crystals of compound 5 could be grown by slow diffusion
of n-pentane into a saturated solution of 5 in CH2Cl2. 5 crystallizes
in the monoclinic space group P21/c (Fig. 6). Unfortunately, only
crystals of low quality were obtained. Although, the X-ray data
collected from 5 was poor, the connectivity of 5 and its composition
could be deduced. However, further bonding parameters shall not
be discussed. As can be seen from Fig. 6 the palladium atom in 5 is
coordinated by two nitrogen atoms and the phosphorous atom of
the Hpypya ligand as well as by one chlorido ligand. Thus, a dis-
torted square planar coordination polyhedron is formed. The gold
atom is linearly coordinated by two chlorido ligands.
Concentration of the reaction mixture which led to 5 resulted in
crop of different crystals which consists of [(Hpypya)
Fig. 3. Solid-state structure of 2 (triclinic), omitting hydrogen atoms. Selected bond
a
ꢁ
ꢀ
lengths [A] and angles [ ]: Pt1eCl1 2.294(2), Pt2eCl2 2.370(2), Pt1eP1 2.185(2), Pt1e
N2 2.019(6), P1eN1 1.672(7), P1eC1 1.801(7), 1.807(8), Pt2eCl3 2.291(2), Pt2eCl4
2.360(2), Pt2eP2 2.189(2), Pt2eN6 2.031(6); Cl1ePt1eCl2 91.35(7), Cl2ePt1eN2
93.5(2), N2ePt1eP1 83.7(2), P1ePt1eCl1 91.91(7), P1ePt1eCl2 174.25(7), Cl1ePt1eN2
173.1(2), Pt1eP1eN1 101.2(2), Pt1eP1eC1 116.8(3), Pt1eN2eC13 119.1(5), N1eP1eC1
106.9(4), C1eP1eC7 106.1(3), N1eC13eN2 116.1(7), Cl3ePt2eCl4 89.97(8), Cl4ePt2e
N6 93.2(2), N6ePt2eP2 83.9(2), P2ePt2eCl3 92.78(8), P2ePt2eCl4 176.25(7), Cl3ePte
N6 176.2(2).
PdCl]2[AuCl2]Cl (50) (Scheme 2) as byproduct which could not be
obtained analytically pure. Although 50 can only be isolated as a
mixture together with 5 the solid state structure could be estab-
lished by single crystal diffraction. 50 crystallizes in the triclinic
space group P-1 with two molecules in the unit cell (Fig. 7). In
contrast to 5 two different anions are found in 50. These are [AuCl2]ꢀ

32
C. Sarcher et al. / Journal of Organometallic Chemistry 758 (2014) 29e35
Scheme 2. Synthesis of 5 and 50.
and Clꢀ. The chloride ion bridges two [(Hpypya)(PdCl)]þ cations via
hydrogen bonding N4eH4eCl5eH8eN8. As observed for 5 the
palladium atoms are coordinated in a distorted square planar
fashion by two nitrogen atoms, the phosphorous atom of the
Hpypya ligand, and one chlorido ligand. Since the two
[(Hpypya)(PdCl)]þ cations have almost the same bonding parame-
ters only one cation is discussed in detail. The Pd1eCl1 distance is
Cl distances of 2.234(5) A and 2.240(5) A. The observed data of the
anion is in agreement with comparable structures such as [NMe4]
ꢀ
ꢀ
[AuCl]2 (CleAueCl: 180ꢁ and AueCl: 2.257(4) A [30]).
ꢀ
3. Summary
In summary, we have synthesized palladium and platinum
complexes with the multidentate ligands Hpypya and Hphpya. In
all compounds the metal atom is coordinated in a distorted square
planar fashion. The NeH function forms hydrogen bonds either to a
polar solvent molecule or to another metal complex. Further re-
action of the pyridyl derivative [(Hpypya)PdCl2] with [AuCl(tht)]
did not result in a bimetallic neutral complex but in a rearrange-
ment of the coordination geometry at the palladium site leading to
the ionic bimetallic compound [(Hpypya)PdCl][AuCl2]. We are
presently investigating this rearrangement caused by a soft Lewis-
acid in more details.
ꢀ
ꢀ
2.287(3) A and the Pd1eP1 distance is 2.195(3) A. The Pd1eN dis-
ꢀ
ꢀ
tances range from 1.981(8) A (Pd1eN2) to 2.105(9) A (Pd1eN1)
showing that the palladium atom is closer located to the pyrimidine
N-atom. The observed distances are in agreement with the litera-
ture, e.g. in [(dppemp)(PdCl)]þ (dppemp ¼ 1-{2-(diphenylphos-
ꢀ
phino)ethyl}-4-methylpiperazine): PdeCl 2.2897(5) A, PdeP
ꢀ
ꢀ
ꢀ
2.2242(5) A, PdeN1 2.033(1) A, PdeN4 2.143(1) A [29]. A distorted
square planar arrangement around the palladium atom which is
formed by N1, N2, P1 and Cl1 is observed. The bite angles of the
ligand are P1ePd1eN2 83.9(3)ꢁ and N1ePd1eN2 79.2(3)ꢁ. The
angles of the trans located atoms are Cl1ePd1eN2 177.7(3)ꢁ and
P1ePd1eN1 162.9(3)ꢁ.
4. Experimental section
As expected the gold atom in the [AuCl2]ꢀ anion is almost lin-
early coordinated having a Cl3eAueCl4 angle of 179.6(2)ꢁ and Aue
Although all products are not veryair-sensitive all manipulations
of air-sensitive materials were performed with the rigorous
exclusion of oxygen and moisture in flame-dried Schlenk-type
glassware either or in an argon-filled MBraun glove box. THF was
distilled under nitrogen from potassium benzophenone ketyl prior
Fig. 5. Solid-state structure of 4, omitting carbon bound hydrogen atoms. Selected
ꢁ
ꢀ
bond lengths [A] and angles [ ]: 2.3565(14), PteCl2 2.2997(14), PteP 2.1788(15), PteN2
2.044(4), PeN1 1.678(5), PeC1 1.797(6), PeC7 1.797(6), N1eH1 0.98(7), OeH1 1.75(7),
N1eH1 2.730(6); Cl1ePteCl2 90.83(5), Cl2ePteP 91.75(5), PePteN2 83.85(13), N2e
PteCl1 93.67(13), Cl1ePteP 175.02(5), Cl2ePteN2 175.33(12), PtePeN1 101.2(2), Pte
PeC1 116.2(2), PtePeC7 120.0(2), PteN2eC13 117.6(3), N1ePeC1 106.5(2), N1ePeC7
106.7(2), C1ePeC7 105.1(3), N1eC13eN2 117.5(4), N1eH1eO 175(5).
Fig. 6. Solid-state structure of 5, omitting hydrogen atoms.

C. Sarcher et al. / Journal of Organometallic Chemistry 758 (2014) 29e35
33
4.2. [(Hpypya)PtCl2] (2)
(a) The reaction was done in air. To 100 mg (0.27 mmol) of
dichloro(1,5-cyclooctadiene)platinum(II) and 95.2 mg (0.27 mmol)
of N-(diphenylphosphino)-4-(pyridin-2-yl)pyrimidin-2-amine 3 ml
of DMSO were added. The mixture was heated with a heat gun and
shacked for 2 min, until the educts were completely dissolved. After
cooling to ambient temperature the product was obtained as yel-
low
crystals.
Yield:
110
mg
(66%).
Anal.
Calcd
C21H17Cl2N4PPt$3C2H6OS, C 37.85, H 4.12, N 6.54, S 11.23, found C
37.82, H 3.71, N 6.59, S 10.54.
(b) 18.7 mg (0.05 mmol) of dichloro(1,5-cyclooctadiene)plati-
num(II) were dissolved in 0.5 ml of DMSO. 17.8 mg (0.05 mmol) of
N-(diphenylphosphino)-4-(pyridin-2-yl)pyrimidin-2-amine were
added under stirring. The yellow mixture was heated to 100 ꢁC,
stirred for 1 h, evaporated and dried in vacuo. Single crystals of 2
were grown by a slow diffusion of n-pentane into a concentrated
solution of 2 in CH2Cl2. Yield: 24.9 mg (80%). 1H NMR (300.13 MHz,
Fig. 7. Solid-state structure of 50, omitting carbon bound hydrogen atoms. Selected
ꢁ
ꢀ
bond lengths [A] and angles [ ]: Pd1eCl1 2.287(3), Pd1eP1 2.195(3), Pd1eN1 2.105(9),
Pd1eN2 1.981(8), P1eN4 1.691(9), P1eC1 1.813(13), P1eC7 1.793(13), Pd2eCl2
2.287(3), Pd2eP2 2.196(3), Pd2eN5 2.096(9), Pd2eN6 1.965(9), AueCl3 2.240(5), Aue
Cl4 2.234(5); Cl1ePd1eP1 95.81(11), Cl1ePd1eN1 101.1(3), P1ePd1eN2 83.9(3), N1e
Pd1eN2 79.2(3), Cl1ePd1eN2 177.7(3), P1ePd1eN1 162.9(3), Pd1eP1eN4 99.9(3),
Pd1eP1eC1 114.9(4), Pd1eP1eC7 119.7(4), N4eP1eC1 106.5(5), N4eP1eC7 107.0(5),
C1ePd1eC7 107.6(6), N2eC13eN4 117.0(9), Cl2ePd2eP2 94.89(12), Cl2ePd2eN5
102.1(3), P2ePd2eN6 84.0(3), N5ePd2eN6 79.1(4), Cl2ePd2eN6 178.4(3), P2ePd2e
N5 162.8(3), N4eCl5eN8 147.9(3), Cl3eAueCl4 179.6(2).
DMSO-d6):
d
(ppm) ¼ 8.81 (d, 3JPH ¼ 3.1, 1H, NH), 8.38 (d, 3JHH ¼ 7.9,
1H, pyridine-6-H), 8.01e7.88 (m, 6H, Ph), 7.77e7.57 (m, 9H, Ph). 31
P
{1H} NMR (121.49 MHz, DMSO-d6):
d
(ppm) ¼ 36.2 (s), 36.2 (d,
1JPtP
¼
3817 Hz). 195Pt NMR(86.02 MHz, DMSO-d6):
d
(ppm) ¼ ꢀ3526 (d, 1JPtP ¼ 3817 Hz). IR (ATR):
n
(cmꢀ1) ¼ 2962 (m),
to use. Hydrocarbon solvents (toluene and n-pentane) were dried
using an MBraun solvent purification system (SPS-800). All solvents
for vacuum line manipulations were stored in vacuo over LiAlH4 in
resealable flasks. Deuterated solvents were obtained from Aldrich
(99 atom % D) and were degassed, dried, and stored in vacuo over Na/
K alloy in resealable flasks. NMR spectra were recorded on a Bruker
Avance II 300 MHz and a Bruker Avance 500 MHz FT-NMR spec-
trometer. Chemical shifts are referenced to internal solvent reso-
nances and are reported relative to tetramethylsilane. IR spectra
were obtained on a Bruker Tensor 34. Raman spectra were carried
out with a Bruker MultiRAM. Mass spectra were recorded at 70 eV on
a Finnigan MAT 8200 and on an Ionspec FTIR spectrometer.
Elemental analyses were carried out with an Elementar Vario Micro
Cube. Dichloro(1,5-cyclooctadiene)palladium(II) and dichloro(1,5-
cyclooctadiene)platinum(II) were purchased from abcr GmbH &
Co. KG. [(tht)AuCl] [31,32] (tht ¼ tetrahydrothiophene) wasprepared
according to modified standard procedures. Hpypya and Hpypya
were prepared according to literature procedures [26].
2924 (m), 2854 (w), 1733 (w), 1598 (m), 1539 (m), 1505 (w), 1426
(m), 1259 (s), 1089 (vs), 1011 (vs), 957 (w), 792 (vs), 710 (w), 689
(m), 666 (w), 649 (w), 544 (m). Raman (solid state):
n
(cmꢀ1) ¼ 3058 (s), 2963 (m), 2906 (s), 1588 (vs),1494 (w), 1436 (w),
1329 (m), 1107 (w), 1045 (m), 1026 (m), 999 (s), 708 (w), 617 (w),
492 (w), 346 (w), 289 (w), 232 (w), 205 (w).
4.3. [(Hphpya)PdCl2] (3)
143 mg (0.50 mmol) of dichloro(1,5-cyclooctadiene)palladium(II)
were dissolved in
5 ml of DMSO. 178 mg (0.50 mmol) of
N-(diphenylphosphino)-4-phenylpyrimidin-2-amine were added
under stirring. The yellow mixture was heated to 100 ꢁC and stirred
for 1 h. After cooling down to ambient temperature the product was
obtained as yellow crystals. Yield: 221 mg (83%). Anal. Calcd
C
22H18Cl2N3PPd$C2H6OS, C 47.19, H 3.96, N 6.88, S 5.25, found C
47.13, H 3.80, N 6.77, S 5.19. 1H NMR (300.13 MHz, CDCl3):
3
d
(ppm) ¼ 9.63 (d, JPH ¼ 5.7 Hz, 1H, NH), 8.14e7.98 (m, 6H, Ph),
3
7.72e7.49 (m, 10H, Ph, pyrimidine-6-H), 7.38 (d, JHH ¼ 6.0 Hz, 1H,
4.1. [(Hpypya)PdCl2] (1)
pyrimidine-5-H).
(ppm) ¼ 64.3. IR (ATR):
31P{1H}
NMR
(121.48
MHz,
CDCl3):
d
n
(cmꢀ1) ¼ 3004 (w), 2911 (w), 2782 (w),
143 mg (0.50 mmol) of dichloro(1,5-cyclooctadiene)palladium(II)
2682 (w),1595 (s),1540 (m),1483 (m),1429 (vs), 1334 (m),1282 (m),
1215 (m),1143 (w), 1103 (m),1013 (s), 951 (vs), 848 (w), 835 (w), 787
(w), 765 (s), 752 (m), 709 (m), 687 (vs), 652 (s), 615 (w), 540 (vs), 524
were dissolved in
5 ml of DMSO. 178 mg (0.50 mmol) of
N-(diphenylphosphino)-4-(pyridin-2-yl)pyrimidin-2-amine were
added under stirring. The yellow mixture was heated to 100 ꢁC and
stirred for 1 h. After cooling down to ambient temperature the
product was obtained as yellow crystals. Yield: 165 mg (62%). Anal.
Calcd C21H17Cl2N4PPd$2C2H6OS, C 43.52, H 4.24, N 8.12, S 9.29, found
C 43.80, H 4.26, N 7.95, S 9.09. 1H NMR (300.13 MHz, CDCl3):
(s). Raman (solid state):
n
(cmꢀ1) ¼ 3058 (s), 3000 (w), 2913 (m),
1594 (vs), 1502 (m), 1370 (w), 1334 (s), 1282 (m), 1216 (w), 1191 (w),
1159 (w), 1144 (w), 1103 (m), 1029 (m), 1016 (m), 1000 (s), 952 (w),
748 (w), 708 (w), 671 (w), 617 (w), 542 (w), 332 (m), 311 (w), 270
(w), 232 (w). FAB-MS: m/z (%) ¼ 495 ([M ꢀ Cl]þ, 30), 460 ([M ꢀ 2Cl]þ,
28).
d
(ppm) ¼ 9.06 (s, br, 1H, NH), 8.40e8.26 (m, 6H, Ph, pyridine-3-H,
3
pyridine-6-H), 8.15 (dd, JHH ¼ 13.6, 7.4 Hz, 1H, pyridine-5-H),
7.84 (s, br, 1H, pyrimidine-6-H), 7.63e7.45 (m, 8H, Ph, pyridine-4-H,
4.4. [(Hphpya)PtCl2] (4)
pyrimidine-5-H). 31P{1H} NMR (121.48 MHz, CDCl3):
d
(ppm) ¼ 72.0.
IR (ATR):
n
(cmꢀ1) ¼ 2921 (m), 2852 (w), 2807 (w), 2535 (w),1593 (s),
93.5 mg (0.25 mmol) of dichloro(1,5-cyclooctadiene)platinum(II)
were dissolved in 5 ml of DMSO. 88.8 mg (0.25 mmol) of
N-(diphenylphosphino)-4-phenylpyrimidin-2-amine were added
under stirring. The yellow mixture was heated to 100 ꢁC and stirred
for 1 h. After cooling down to ambient temperature the product was
obtained as yellow crystals. Yield: 121 mg (78%). Anal. Calcd
1550 (s),1495 (vs), 1465 (vs),1436 (m),1404 (m),1328 (m),1306 (m),
1285 (w),1261 (w),1219 (m),1108 (s),1047 (vs),1017 (vs), 956 (s), 858
(s), 795 (s), 766 (s), 751 (m), 708 (m), 690 (s), 650 (w), 635 (m), 541
(vs), 510 (s). Raman (solid state):
n
(cmꢀ1) ¼ 3053 (s), 2994 (w), 2911
(m),1592 (vs),1495 (w),1467 (w),1409 (m),1330 (vs),1307 (w),1269
(w), 1223 (w), 1108 (m), 1038 (s), 1020 (s), 997 (vs), 959 (w), 754 (w),
705 (m), 674 (s), 616 (w), 543 (w), 383 (w), 346 (m), 310 (w), 278
(w). FAB-MS: m/z (%) ¼ 497 ([M ꢀ Cl]þ, 100), 461 ([M ꢀ 2Cl]þ, 16).
C
H
d
22H18Cl2N3PPt$C2H6OS, C 41.21, H 3.46, N 6.01, S 4.58, found C 41.00,
3.37, N 5.79, S
4.45. 1H NMR (300.13 MHz, DMSO-d6):
(ppm) ¼ 9.06 (d, 3JPH ¼ 6.5 Hz, 1H, NH), 8.10 (d, 3JHH ¼ 7.6 Hz, 2H,

34
C. Sarcher et al. / Journal of Organometallic Chemistry 758 (2014) 29e35
Ph), 8.02 (d, 3JHH ¼ 7.2 Hz, 2H, Ph), 7.98 (d, 3JHH ¼ 7.1, 2H, Ph), 7.66e
measured, 6242 independent reflections (Rint ¼ 0.0538). The final
R1 values were 0.0276 (I > 2
(I)). The final wR(F2) values were
0.0491 (all data). The goodness of fit on F2 was 0.941.
Crystal data for (triclinic) 2(C21H17Cl2N4PPt)$C2H6OS,
3
7.51 (m, 10H, Ph, pyrimidine-6-H), 7.35 (d, JHH ¼ 6.6 Hz, 1H, py-
s
rimidine-5-H). 31P{1H} NMR (121.48 MHz, DMSO-d6):
d
(ppm) ¼ 36.1
1
(s), 36.1 (d, JPtP ¼ 3841 Hz). 195Pt NMR (64.30 MHz, DMSO-d6):
2
(ppm) ¼ ꢀ3538 (d, 1JPtP ¼ 3841 Hz). IR (ATR):
n
(cmꢀ1) ¼ 3027 (w),
M ¼ 1322.82, triclinic, a ¼ 10.3304(5) A, b ¼ 13.1342(6) A,
ꢀ
ꢀ
d
2963 (w), 2908 (w), 2784 (w), 2699 (w), 1601 (s), 1540 (s), 1484 (m),
1431 (vs), 1334 (w), 1275(m), 1261 (m), 1217 (m), 1187 (w), 1146 (w),
1105 (s), 1013 (vs), 949 (s), 801 (m), 764 (s), 712 (s), 686 (vs), 655 (s),
c ¼ 17.7250(8) A,
a
ꢀ
¼ 89.259(4)ꢁ,
b
¼ 80.600(4)ꢁ,
g
¼ 75.038(4)ꢁ,
ꢀ
3
V ¼ 2291.14(18) A , T ¼ 173(2) K, space group P-1, Z ¼ 2,
m
(MoK
a
) ¼ 6.493 mmꢀ1, 21,851 reflections measured, 8340 inde-
616 (w), 546 (vs), 532 (vs). Raman (solid state):
n
(cmꢀ1) ¼ 3058 (m),
pendent reflections (Rint ¼ 0.0574). The final R1 values were 0.0369
2999 (w), 2913 (m), 1597 (vs), 1505 (m), 1441 (w), 1375 (w), 1335 (s),
1284 (w), 1218 (w), 1192 (w), 1160 (w), 1147 (w), 1106 (w), 1088 (w),
1024 (m), 1001 (s), 951 (w), 748 (w), 705 (w), 671 (w), 617 (w), 340
(w), 287 (w), 214 (w). FAB-MS: m/z (%) ¼ 584 ([M ꢀ Cl]þ, 2), 550
([M ꢀ 2Cl]þ, 2).
(I > 2
goodness of fit on F2 was 0.965.
Crystal data for 3: 22H18Cl2N3PPd$C2H6OS,
monoclinic, a ¼ 10.2114(3) A, b ¼ 11.8759(3) A, c ¼ 21.8722(6) A,
s
(I)). The final wR(F2) values were 0.0928 (all data). The
C
M
¼
610.79,
ꢀ
ꢀ
ꢀ
3
ꢀ
ꢁ
b
¼ 92.3231(23) , V ¼ 2650.26(12) A , T ¼ 150(2) K, space group
P21/c, Z ¼ 4,
m
(MoK
a
) ¼ 1.063 mmꢀ1, 21,773 reflections measured,
4.5. [(Hpypya)PdCl][AuCl2] (5)
6091 independent reflections (Rint ¼ 0.0432). The final R1 values
were 0.0299 (I > 2
(I > 2
(I)). The goodness of fit on F2 was 1.009.
Crystal data for 4: C22H18Cl2N3PPt$C2H6OS, M ¼ 699.48, mono-
s
(I)). The final wR(F2) values were 0.0681
143 mg (0.50 mmol) of dichloro(1,5-cyclooctadiene)palladium(II)
s
were dissolved in
5 ml of DMSO. 178 mg (0.50 mmol) of
ꢀ
ꢀ
ꢀ
N-(diphenylphosphino)-4-(pyridin-2-yl)pyrimidin-2-amine were
added under stirring. The yellow mixture was heated to 100 ꢁC and
stirred for 1 h. After cooling down to ambient temperature 160 mg
(0.50 mmol) of chloro(tetrahydrothiophene)gold(I) were added. The
yellow solution was heated to 100 ꢁC and stirred for 15 min. After
cooling down to ambient temperature the solution was evaporated.
The remaining residue was subsequently dried in vacuo. The product
was obtained as a yellow powder. Yield: 337 mg (88%). Anal. Calcd
clinic, a ¼ 10.1398(3) A, b ¼ 11.7931(4) A, c ¼ 21.7884(8) A,
3
ꢀ
ꢁ
b
¼ 92.618(3) , V ¼ 2602.73(15) A , T ¼ 200(2) K, space group P21/c,
Z ¼ 4,
m
(MoK
a
) ¼ 5.760 mmꢀ1, 25,661 reflections measured, 6128
independent reflections (Rint ¼ 0.0682). The final R1 values were
0.0375 (I > 2s
(I)). The final wR(F2) values were 0.0986 (all data). The
goodness of fit on F2 was 1.068.
Crystal data for 5: 2(C21H17AuCl3N4PPd)$CH2Cl2, M ¼ 1617.07,
ꢀ
ꢀ
ꢀ
monoclinic, a ¼ꢁ 20.545(4) A, b ¼ 17.5710(22) A, c ¼ 13.968(3) A,
3
ꢀ
C
21H17AuCl3N4PPd$C2H6OS, C 32.72, H 2.75, N 6.64, S 3.80, found C,
b
¼ 102.003(15) , V ¼ 4931.9(15) A , T ¼ 173(2) K, space group P21/c,
32.30, H 3.01, N 6.05, S 3.96. 1H NMR (300.13 MHz, CDCl3):
Z ¼ 4.
d
(ppm) ¼ 9.04 (s, br, 1H, NH), 8.25e8.10 (m, 4H, Ph), 7.98e7.73 (m,
Crystal data for 50: 2(C21H17ClN4PPd)$AuCl2$Cl, M ¼ 1299.73,
ꢀ
ꢀ
ꢀ
3H, pyridine-3-H, pyridine-5-H, pyridine-6-H), 7.71e7.37 (m, 9H, Ph,
triclinic, a ¼ 9.5170(5) A, b ¼ 15.2755(8) A, c ¼ 16.7857(9) A,
3
ꢀ
pyridine-4-H, pyrimidine-5-H, pyrimidine-6-H). 31P{1H} NMR
a
¼ 113.897(4)ꢁ,
b
¼ 91.011(4)ꢁ,
g
¼ 90.754(4) , V ¼ 2230.16(20) A ,
ꢁ
(121.48 MHz, CDCl3):
d
(ppm) ¼ 71.2. IR (ATR):
n
(cmꢀ1) ¼ 3048 (w),
T ¼ 200(2) K, space group P-1, Z ¼ 2,
m
(MoK
a
) ¼ 4.492 mmꢀ1, 21,987
2963 (w), 1733 (w), 1645 (w), 1591 (m), 1550 (m), 1505 (s), 1464 (m),
1435 (m),1419 (m), 1331 (m),1297 (w),1260 (m),1216 (m),1194 (m),
1142 (w), 1103 (s), 1009 (vs), 951 (s), 840 (m), 786 (s), 769 (m), 754
(m), 706 (m), 692 (vs), 636 (m), 536 (vs), 509 (m). Raman (solid
reflections measured, 8105 independent reflections (Rint ¼ 0.0906).
The final R1 values were 0.0706 (I > 2s
(I)). The final wR(F2) values
were 0.2248 (all data). The goodness of fit on F2 was 1.068.
state):
n
(cmꢀ1) ¼ 3057 (w), 2911 (w), 1587 (s), 1477 (m), 1329 (w),
Acknowledgements
1105 (w), 1037 (w), 1026 (w), 998 (m), 346 (w), 276 (s). ESI-MS
(DCM): m/z ¼ 499.00 ([(Hpypya)(PdCl)]þ).
This work was supported by the DFG-funded Transregional
Collaborative Research Center SFB/TRR 88 “Cooperative effects
in homo- and hetero-metallic complexes (3MET)”. C.S. thanks
the Konrad-Adenauer-Stiftung for a doctoral fellowship. L.T.G.
thanks the Carl Daimler and Carl Benz foundation for a doctoral
fellowship.
4.6. X-ray crystallographic studies of 1e50
Single crystals were grown as described in the synthetic pro-
cedures of each compound. Suitable crystals were covered in
mineral oil (Aldrich) and mounted onto a glass fiber. Data were
collected on diffractometer equipped with a STOE imaging plate
Appendix A. Supplementary material
detector system IPDS2 using MoK
a
radiation with graphite mono-
ꢀ
chromatization (
l
¼ 0.71073 A) at low temperatures. Subsequent
CCDC 970717 to 970721 and 973143 contain the supplementary
crystallographic 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.
computations were carried out on an Intel Core2Quad. Structure
solution was performed by direct methods; full-matrix-least
squares refinement against F2 using SHELXS-97 and SHELXL-97
software [33]. Figs. 1e6 were generated using the program Dia-
mond 3.2 [34].
References
Crystal data for 1: C21H17Cl2N4PPd$3(C2H6OS), M ¼ 768.04,
ꢀ
ꢀ
ꢀ
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