Cyclohexanone selenosemicarbazone: A convenient starting material for the preparation of functionalised selenosemicarbazones and their Pt and Pd complexes

Article abstract of DOI:10.1016/j.jorganchem.2010.03.029

The reaction of hydrazine hydrate with KSeCN in acidic aqueous ethanol in the presence of cyclohexanone affords cyclohexanone selenosemicarbazone in good yields. Cyclohexanone selenosemicarbazone was converted into various functionalised selenosemicarbazones by treatment with aldehydes. Salicylaldehyde selenosemicarbazone and its 1,2-naphthyl-derivative were prepared and reacted with some Pd(II) and Pt(II) phosphine complexes to give compounds of the type [M(L^Se)(P)] where M = Pt and Pd, L^Se is the doubly deprotonated selenosemicarbazone and P a monodentate phosphine. In these complexes the ligands act as tridentate, dianionic [Se-N-O]^2- ligands, which was confirmed by single-crystal X-ray diffraction of the Pd derivative.

Full text of DOI:10.1016/j.jorganchem.2010.03.029

Journal of Organometallic Chemistry 695 (2010) 1657e1662
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Journal of Organometallic Chemistry
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Cyclohexanone selenosemicarbazone: A convenient starting material for the
preparation of functionalised selenosemicarbazones and their Pt and
Pd complexes
*
Patrick Bippus, Anja Molter, David Müller, Fabian Mohr
Fachbereich C e Anorganische Chemie, Bergische Universität Wuppertal, 42119 Wuppertal, Germany
a r t i c l e i n f o
a b s t r a c t
Article history:
The reaction of hydrazine hydrate with KSeCN in acidic aqueous ethanol in the presence of cyclohexa-
none affords cyclohexanone selenosemicarbazone in good yields. Cyclohexanone selenosemicarbazone
was converted into various functionalised selenosemicarbazones by treatment with aldehydes. Salicy-
laldehyde selenosemicarbazone and its 1,2-naphthyl-derivative were prepared and reacted with some Pd
(II) and Pt(II) phosphine complexes to give compounds of the type [M(LSe)(P)] where M ¼ Pt and Pd, LSe is
the doubly deprotonated selenosemicarbazone and P a monodentate phosphine. In these complexes the
ligands act as tridentate, dianionic [SeeNeO]2- ligands, which was confirmed by single-crystal X-ray
diffraction of the Pd derivative.
Received 10 February 2010
Received in revised form
24 March 2010
Accepted 28 March 2010
Available online 21 April 2010
Keywords:
Selenium
Tridentate ligands
Palladium
Ó 2010 Elsevier B.V. All rights reserved.
Platinum
X-ray structure
1. Introduction
group-metals [10]. We now wished to extend this chemistry to
include tridentate, dianionic [SeeNeO]2ꢀ ligands, derived from
Selenosemicarbazide, H2NC(Se)NHNH2, has been used as
convenient commercially available starting material for the
synthesis of a variety of N-functionalised selenosemicarbazones.
These have been shown to act as monoanionic [SeeNeN]ꢀ
ligands in metal complexes containing Pt, Pd, Zn and Cd (Chart 1)
[1e3]. However, selenosemicarbazide has recently been dis-
continued by chemical suppliers (in Europe at least) and is no
longer available commercially, thus the need arose to find an
alternative material that could easily be prepared and conve-
niently handled and stored. In the literature from the 1950s there
are various descriptions for the preparation of acetone seleno-
semicarbazone and cyclohexanone selenosemicarbazone as well
as their conversion into other substituted selenosemicarbazones
[4,5]. Given the higher yield and better storage stability of the
cyclohexanone derivative, we optimised the synthetic procedure
from the patent literature [6] and spectroscopically and struc-
turally characterised the product for the first time. We have
recently begun a systematic investigation of the coordination
chemistry of organoselenium compounds containing the eNHC
(Se)e unit with gold [7e9] and other transition- and main-
the reaction of cyclohexanone selenosemicarbazone with
hydroxyl-functionalised aldehydes. Such ligands should be able
to form complexes with square planar transition metals in the
oxidation state þ2 such as Pd and Pt (Chart 1). Indeed, the Ni(II)-
phosphine complex containing the dianion derived from salicy-
laldehyde selenosemicarbazone (Chart 1) was reported and
structurally characterised in 1974 [11]. Since then however, no
one appears to have worked with this ligand system.
2. Results and discussion
The reaction of hydrazine hydrate with KSeCN in aqueous
ethanol under acidic conditions in the presence of cyclohexanone
affords cyclohexanone selenosemicarbazone in yields greater than
60%. The material can be stored without apparent decomposition at
room temperature in amber glass bottles for several months. During
the preparation significant amounts of black selenium metal are
formed which can be recovered and reused in the synthesis of
KSeCN, thus making the overall reaction quite atom efficient with
respect to selenium metal. Cyclohexanone selenosemicarbazone
was characterised by NMR spectroscopyand also bysingle-crystal X-
ray diffraction. The proton NMR spectrum shows the expected
multiplets for the cyclohexane ring as well as two broad signals for
* Corresponding author.
E-mail address: fmohr@uni-wuppertal.de (F. Mohr).
0022-328X/$ e see front matter Ó 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2010.03.029

1658
P. Bippus et al. / Journal of Organometallic Chemistry 695 (2010) 1657e1662
Cyclohexanone selenosemicarbazone reacts with various func-
NH2
Se
MII
tionalised aldehydes in water or watereethanol mixtures in the
presence of acetic acid to give good yields of the mono- and bis-
selenosemicarbazones 2-5 as shown in Scheme 1.
NH2
Se
MII
N
N
N
N
The four compounds were fully characterised by spectroscopic
techniques, the data (see Experimental) being fully consistent with
the proposed structures. The 77Se-NMR chemical shifts of
compounds 2-4 are all around 200 ppm, typical for compounds
containing the C]Se unit. The hydroxyl-functionalised selenose-
micarbazones H2L1Se (2) and H2L2Se (3) react with the palladium(II)
and platinum(II) phosphine complexes cis or trans-[MCl2(P)2]
where M ¼ Pt, Pd and P ¼ Ph3P or PTA (PTA ¼ 1,3,5-triaza-7-phos-
phaadamantane) in the presence of a base to afford the yellow or
orange complexes [M(LSe)(P)] 6-9 as air-stable solids in good yields
as shown in Scheme 2.
L
L
N
O
L = anionic ligand
L = neutral ligand
NH2
Se
Ni
N
N
Although the compounds are air-stable in the solid state, in
solution precipitation of a dark solid occurs after ca. 24 h. Never-
theless, complexes 6-9 were fully characterised by spectroscopic
methods and, in the case of 6, by X-ray crystallography. The 31P{1H}
NMR spectra of complexes 6-9 show singulet resonances at
chemical shifts typical for the coordinated phosphines. In addition,
PPh3
O
Chart 1.
1
the Pt-derivative 7 displays Pt-satellites with JPtꢀP ¼ 3562 Hz.
Unfortunately, for the structurally related sulfur complex [Pt(L2S)
(PPh3)] no 31P NMR spectroscopic data has been reported for
comparison [12]. Due to the instability and also poor solubility of
the complexes, we were unable to measure 77Se NMR spectra of any
of the metal complexes. The deprotonation of both the hydroxyl
and the NH functionalities of the selenosemicarbazone is apparent
from the disappearance of the NH and OH proton signals in the 1H
NMR spectra of compounds 6-9. This data supports the proposed
structure, in which the selenosemicarbazone acts as a dianionic
[SeeNeO]2ꢀ ligand towards the metal. This was indeed confirmed
by an X-ray diffraction experiment of complex 6, the molecular
structure of which is shown in Fig. 4.
the NH2 group and a singulet at 10.41 ppm due to the NH proton. In
the 13C NMR spectrum the carbon atom of the C]Se group is
observed at ca. 174 ppm with 77Se satellites (1JSeꢀC ¼ 209 Hz). The
signals due tothe other carbon atoms in the molecule appear at their
expected chemical shifts. Slow evaporation of an ethanolic solution
gave large, colourless crystals which were subjected to an X-ray
diffraction study. The molecular structure of cyclohexanone sele-
nosemicarbazone (1) is shown in Fig. 1, important bond distances
and angles are collected in the figure caption.
The molecule consists of a planar H2NC(Se)NHN]C unit to
which the cyclohexane ring is attached in chair conformation. In
the crystal two molecules of 1 form a dimer through a pair of SeeH
bonds of ca. 2.7 A as shown in Fig. 2. In addition, there is an
intramolecular NeH bond between the C]N and NH2 units.
The dianionic selenosemicarbazone binds to the metal through
Se, the imine N and O; the Ph3P ligand, located trans to the imine
nitrogen atom, completes the square planar coordination geometry
about the Pd atom. Thus, the planar, tridentate Se, N, O-ligand forms
one five- and one six-membered ring incorporating the palladium
atom. The overall geometry is similar to that of the related sulfur
complex [Pd(L2S)(PPh3)] [13], except that some bond distances and
angles are different, as expected when sulfur is exchanged for the
larger selenium. The PdeP, PdeN and PdeO bond distances in
complex 6 are very similar to those in [Pd(L2S)(PPh3)], whilst the
PdeSe distance of 2.3414(3) Å is similar to that observed in the
ꢀ
Furthermore, the second H atom of the NH2 group forms a slightly
ꢀ
longer (ca. 2.9 A) SeeH bond to an adjacent dimeric unit with an
angle of ca. 45ꢁ. Overall, an infinite network of dimeric units (Fig. 3)
is formed via SeeH bonds.
selenourea Pd-complexes [Pd{
C6H5C(O)NC(Se)NMePh}] and [Pd{
k
2C,N-4-MeC6H3N(Me)NO}{
k
k
2Se,O-
2Se,O-C6H5C(O)NC(Se)NnBu2}2]
in which the PdeSe distances are 2.3470(4) and 2.3411(3) Å,
respectively [14,15]. In contrast to the sulfur analogue [Pd(L2S)
(PPh3)], which forms a dimeric unit via a pair of intermolecular H-
bonds between N(3)H2 and N(2) of the adjacent molecule [13], there
are no H-bonding interactions in complex 6. There are however
aromatic p-stacking interactions between the naphthyl ring and one
of the phenyl rings of the Ph3P ligand in the range of ca. 3.2e3.8 Å.
We also attempted to prepare Pd complexes using HL3Se (4) and
H2L4Se (5). However, in the case of HL3Se, we obtained complex
product mixtures which we were unable to separate. Ligand H2L4Se
gave dark, insoluble materials which we could not characterise. We
are currently investigating reactivity of these two ligands in more
detail.
In summary, we have shown here that cyclohexanone seleno-
semicarbazone is readily accessible from simple precursors and can
be further functionalised by the reaction with various aldehydes
including salicylaldehyde. Doubly deprotonated salicylaldehyde
selenosemicarbazone forms metals complexes with Pt and Pd
Fig. 1. Molecular structure of 1. Ellipsoids show 50% probability levels. Hydrogen
atoms are shown as spheres with arbitrary radii. Selected bond distances [Å]: C(1)-Se
(1) 1.8565(19), C(1)-N(1) 1.315(3), C(1)-N(2) 1.336(2), N(2)-N(3) 1.386(2), N(3)-C(2)
1.285(2). Selected angles [ꢁ]: N(2)-C(1)-Se(1) 118.72(15), N(1)-C(1)-Se(1) 123.54(16), N
(1)-C(1)-N(2) 117.70(18), C(1)-N(2)-N(3) 119.22(17), N(2)-N(3)-C(2) 117.89(16).

P. Bippus et al. / Journal of Organometallic Chemistry 695 (2010) 1657e1662
1659
Fig. 2. Packing diagram of compound 1 showing the formation of dimeric units through Se-H bonds as well as intramolecular N-H bonds.
phosphine complexes, which were spectroscopically and structur-
ally characterised.
(400 MHz, CDCl3, 25ꢁC):
d
¼ 10.41 (s, 1 H, NH), 8.34 (br. s, 1 H, NH2),
7.95 (br. s, 1 H, NH2), 2.39 (m, 2 H, Cy ring), 2.20 (t, J ¼ 5.8 Hz, 2 H, Cy
ring), 1.58-1.65 (m, 2 H, Cy ring), 1.50e1.57 (m, 4 H, Cy ring). 13C
NMR (100 MHz, CDCl3, 25 ꢁC):
d
¼ 173.77 (1JCeSe ¼ 209 Hz, C]Se),
3. Experimental
159.23 (C]N), 34.84, 27.54, 26.82, 25.70, 24.94 (Cy ring). 77Se NMR
(76 MHz, CDCl3, 25 ꢁC):
d
¼ 172. Anal. calc. for C7H13N3Se (218.16):
3.1. General
C, 38.54; H, 6.01; N, 19.26. Found: C, 38.34; H, 5.99; N, 19.54 %. X-ray
quality crystals were obtained by slow evaporation of an ethanolic
solution of the compound.
1H, 13C, 77Se and 31P{1H} NMR spectra were recorded on
a 400 MHz Bruker Avance or 600 MHz Bruker Avance II spec-
trometer. Chemical shifts are quoted relative to external SiMe4 (1H,
13C), Me2Se (77Se) and 85% H3PO4
(
31P). Elemental analyses were
3.3. H2L1Se (2)
performed by staff of the microanalytical laboratory of the
University of Wuppertal. All reactions were carried out under
aerobic conditions unless stated otherwise. KSeCN as well as the Pt
and Pd phosphine complexes [MCl2(P)2] [M ¼ Pt, Pd; P ¼ PPh3, PTA]
were prepared as described in the literature [16e18]. All other
chemicals and solvents (HPLC grade) were sourced commercially
and used as received.
A mixture of cyclohexanone selenosemicarbazone (0.474 g,
2.17 mmol) and 2-hydroxynaphthaldehyde (0.375 g, 2.18 mmol) in
EtOH (20 mL) containing 1 mL glacial acetic acid was refluxed for
ca. 1 h. The resulting yellow solid was isolated by filtration and was
dried in air to give 0.366 g (58%) of the product. 1H NMR (400 MHz,
dmso-d6, 25 ꢁC):
d
¼ 11.65 (br. s, 1 H, NH), 10.50 (br. s, 1 H, OH), 9.15
(s, 1 H, HC]N), 8.64 (br. s, 1 H, NH2), 8.52 (d, J ¼ 8.7 Hz, 1 H, H8),
8.33 (br. s, 1 H, NH2), 7.89 (d, J ¼ 8.9 Hz, 1 H, H4), 7.85 (d, J ¼ 8.3 Hz,1
H, H5), 7.56 (dt, J ¼ 8.3, 1.3 Hz, 1 H, H7), 7.37 (dt, J ¼ 7.8, 0.9 Hz, 1 H,
H6), 7.19 (d, J ¼ 9.2 Hz, 1 H, H3). 13C NMR (100 MHz, dmso-d6, 25
3.2. Cyclohexanone selenosemicarbazone (1)
To a mixture of EtOH (200 mL) and water (25 ml) was added
hydrazine hydrate (7.5 mL), concentrated HCl (10 mL) and a solu-
tion of KSeCN (7.2 g, 0.05 mol) in water (25 mL). Subsequently,
cyclohexanone (16 mL) was added and the mixture was heated to
reflux for 2 h. After this time the solution was filtered while hot to
remove some gray selenium. The filtrate was concentrated in
vacuum to ca. 20 mL to give a pale yellow oil which solidified on
cooling. The solid was isolated by filtration, was washed with water
and left to dry in air. The dry solid was then dissolved in CHCl3
filtered through celite and the filtrate was evaporated to dryness to
afford 7.6 g (71 %) of the product as a colourless solid. 1H NMR
ꢁC):
d
¼ 172.60 (C]Se), 156.93 (C2), 144.66 (C]N), 132.95 (C4),
131.59 (C9), 128.76 (C5), 128.16 (C10), 128.08 (C7), 123.61(C6),
123.05 (C8), 118.41 (C3), 109.68 (C1). 77Se NMR (76 MHz, dmso-d6,
25 ꢁC):
d
¼ 202. Anal. calc. for C12H11N3OSe (292.20): C, 49.33; H,
3.79; N, 14.38. Found: C, 49.34; H, 3.73; N, 14.45 %.
3.4. H2L2Se (3)
This was prepared as described above using cyclohexanone
selenosemicarbazone (0.362 g, 1.66 mmol) and salicylaldehyde
Fig. 3. . Packing diagram of compound 1 showing the network structure formed through SeeH bonds between dimeric units.

1660
P. Bippus et al. / Journal of Organometallic Chemistry 695 (2010) 1657e1662
Se
H2NNH2
N
KSeCN
N
H
NH2
O
1
( )
O
R
H
NH2
Se
NH2
Se
NH2
HN
N
HN
N
HN
N
Se
OH
N
N
OH
HN
H2N
NH
NH2
S
Se
Se
Se
Se
H2L1
H2L2
(3)
Se
HL3
4
Se
H2L4
2
( )
( )
5
( )
Scheme 1.
(0.175 mL, 1.66 mmol). 0.313 g (89%) of a yellow solid was obtained.
1H NMR (400 MHz, dmso-d6, 25 ꢁC):
phthaloyldicarboxaldehyde (0.164 g, 1.22 mmol). 0.332 g (78%) of
d
¼ 11.63 (s, 1 H, NH), 9.87 (br.
a colourless solid was obtained. 1H NMR (400 MHz, dmso-d6, 25
s, 1 H, OH), 8.51 (br. s, 1 H, NH2), 8.48 (s, 1 H, HC]N), 8.39 (br. s, 1 H,
NH2), 7.92 (dd, J ¼ 7.5, 1.4 Hz, 1 H, H6), 7.22 (dt, J ¼ 7.4, 1.8 Hz, 1 H,
H4), 6.86 (d, J ¼ 8.2 Hz, 1 H, H3), 6.81 (t, J ¼ 7.5 Hz, 1 H, H5).13C NMR
ꢁC):
d
¼ 11.79 (s, 2 H NH), 8.68 (br. s, 2 H, NH2), 8.56 (br. s, 2 H, NH2),
8.23 (s, 1 H, H2), 8.18 (s, 2 H, HC]N), 7.85 (dd, J ¼ 7.8,1.5 Hz, 2 H, H4,
H6), 7.44 (t, J ¼ 7.7 Hz,1 H, H5). 13C NMR (100 MHz, dmso-d6, 25 ꢁC):
(100 MHz, dmso-d6, 25 ꢁC):
d
¼ 173.13 (C]Se), 156.59 (C2), 141.18
d
¼ 173.87 (C]Se), 143.03 (C]N), 134.63 (C1, C3), 129.10 (C4, C5,
(C]N), 131.41 (C4), 126.93 (C6), 120.14 (C1), 119.32 (C5), 116.10 (C3).
C6), 126.01 (C2). Anal. calc. for C10H12N6Se2 (374.16): C, 32.10; H,
3.23; N, 22.46. Found: C, 32.46; H, 3.28; N, 22.66 %.
77Se NMR (114 MHz, dmso-d6, 25 ꢁC):
d
¼ 197. Anal. calc. for
C8H9N3OSe (242.14): C, 39.68; H, 3.75; N, 17.35. Found: C, 39.76; H,
3.69; N, 17.12 %.
3.7. Preparation of the metal complexes
3.5. HL3Se (4)
To a suspension of the metal precursor (0.100 g) in toluene
(10 mL) was added the appropriate functionalised selenosemi-
carbazone (1 eq.) and Et3N (1 ml). The mixture was stirred at room
temperature for ca. 8 h. The orange or yellow solution was passed
through a short column of celite and the filtrate was evaporated to
dryness. The resulting solids were crystallised from CH2Cl2/hexane
or CH2Cl2/Et2O.
This was prepared as described above using cyclohexanone
selenosemicarbazone
(0.355 g,
1.63 mmol)
and
2-thio-
phenecarboxaldehyde (0.15 mL, 1.63 mmol). 0.269 g (80%) of a pale
1
yellow solid was obtained. H NMR (400 MHz, dmso-d6, 25 ꢁC):
d
¼ 11.68 (s, 1 H, NH), 8.59 (br. s, 1 H, NH2), 8.34 (s, 1 H, HC]N), 8.04
(br. s, 1 H, NH2), 7.68 (dd, J ¼ 5.0, 0.5 Hz, 1 H, H5), 7.49 (dd, J ¼ 3.6,
0.5 Hz, 1 H, H3), 7.12 (dd, J ¼ 5.0, 3.7 Hz, 1 H, H4). 13C NMR
3.8. [Pd(L1Se)(PPh3)] (6)
(100 MHz, dmso-d6, 25 ꢁC):
d
¼ 173.19 (C]Se), 138.94 (C]N),
131.08 (C3), 129.29 (C5), 127.99 (C4). 77Se NMR (114 MHz, dmso-d6,
This was prepared as described above from trans-[PdCl2(PPh3)2]
(0.100 g, 0.142 mmol) and H2L1Se (0.042 g, 0.144 mmol). 0.061 g
(65%) of an orange solid was obtained. 1H NMR (400 MHz, CDCl3,
25 ꢁC):
d
¼ 201. Anal. calc. for C6H7N3SSe (232.16): C, 31.04; H, 3.04;
N, 18.10. Found: C, 30.97; H, 3.18; N, 18.28%.
25 ꢁC):
d
¼ 9.26 (d, JPeH ¼ 13.3 Hz, 1 H, HC]N), 8.09 (d, J ¼ 8.6 Hz, 1
3.6. H2L4Se (5)
H, H8), 7.72e7.79 (m, 6 H, o-Ph3P), 7.64 (dd, J ¼ 7.9, 1.2 Hz, 1 H, H5),
7.59 (d, J ¼ 9.1 Hz, 1 H, H4), 7.42e7.54 (m, 10 H, m-Ph3P, p-Ph3P, H7),
7.22 (dt, J ¼ 7.9, 0.9 Hz, 1 H, H6), 6.82 (d, J ¼ 9.0 Hz,1 H, H3), 4.76 (br.
This was prepared as described above using cyclohexanone
selenosemicarbazone
(0.505 g,
2.31 mmol)
and
iso-
s, 2 H, NH2). 13C NMR (100 MHz, CDCl3, 25 ꢁC):
d
¼ 163.21 (C2),
NH2
NH2
Se
HN
N
L1
Se
OH
N
N
Se
[MCl2(P)]
Et3N
6
M = Pd, P = PPh3 ( )
M P
M = Pt, P = PPh3 (7)
O
Se
L2
M = Pd, P = PPh3 (8)
9
M = Pd, P = PTA ( )
Se
H2L1 H2L2
Se
Scheme 2.

P. Bippus et al. / Journal of Organometallic Chemistry 695 (2010) 1657e1662
1661
J ¼ 8.6 Hz, 1 H, H3), 6.62 (dt, J ¼ 8.0, 1.2 Hz, 1 H, H4), 4.80 (br. s, 1 H,
NH2). 13C NMR (100 MHz, CDCl3, 25 ꢁC):
d
¼ 163.06 (C2), 161.35 (d,
JPeC ¼ 10.6 Hz, CSe), 155.30 (d, JPeC ¼ 2.9 Hz, C¼N), 134.57 (d,
JPeC ¼ 11.4 Hz, o-Ph3P), 134.38 (C6), 133.51 (C5), 131.04 (d,
JPeC ¼ 2.7 Hz, p-Ph3P), 129.91 (d, JPeC ¼ 50.8 Hz, ipso-Ph3P), 128.34
(d, JPeC ¼ 10.9 Hz, m-Ph3P), 120.55 (d, JPeC ¼ 2.2 Hz, C3), 117.34 (C1),
114.58 (C4).31P{1H} NMR (162 MHz, CDCl3, 25 ꢁC):
calc. for C26H22N3OPSePd (608.83): C, 51.29; H, 3.64; N, 6.90. Found:
C, 51.04; H, 3.90; N, 6.59 %.
d
¼ 22.09. Anal.
3.11. [Pd(L2Se)(PTA)] (9)
This was prepared as described above from cis-[PdCl2(PTA)2]
(0.100 g, 0.202 mmol) and H2L2Se (0.049 g, 0.202 mmol). 0.056 g
(55%) of a yellow solid was obtained. 1H NMR (400 MHz, CDCl3, 25
ꢁC):
d
¼ 8.22 (d, JP-H ¼ 12.8 Hz, 1 H, HC¼N), 7.30 (dt, J ¼ 8.7, 1.7 Hz, 1
H, H5), 7.25 (d, J ¼ 8.5 Hz, 1 H, H6), 6.99 (d, J ¼ 8.4 Hz, 1 H, H3), 6.63
(t, J ¼ 7.6 Hz, 1 H, H4), 5.17 (br. s, 2 H, NH2), 4.56 (AB quart.,
J ¼ 13.7 Hz, 6 H, NCH2N), 4.36 (s, 6 H, PCH2N). 13C NMR (100 MHz,
CDCl3, 25 ꢁC):
d
¼ 162.79 (C2), 160.43 (d, JPeC ¼ 12.7 Hz, CSe), 152.57
(d, JPeC ¼ 2.5 Hz, C¼N), 134.65 (C6), 133.71 (C5), 120.54 (d,
JPeC ¼ 1.4 Hz, C3), 117.27 (C1), 115.01 (C4), 73.15 (d, JPeC ¼ 7.7 Hz,
NCH2N), 51.66 (d, JPeC ¼ 16.8 Hz, PCH2N). 31P{1H} NMR (162 MHz,
Fig. 4. Molecular structure of complex 6. Ellipsoids show 50% probability levels.
Hydrogen atoms have been omitted for clarity. Selected bond distances [Å]: Pd(1)-Se
(1) 2.3414(3), Pd(1)-O(1) 2.0388(17), Pd(1)-N(1) 2.0256(19), Pd(1)-P(1) 2.2679(6), Se
(1)-C(12) 1.911(3), C(12)-N(3) 1.369(3), C(12)-N(2) 1.285(3), N(2)-N(1) 1.403(3), N(1)-C
(11) 1.291(3). Selected angles [ꢁ]: P(1)-Pd(1)-N(1) 176.77(6), Se(1)-Pd(1)-O(1) 177.03
(5), Se(1)-Pd(1)-P(1) 91.878(19), O(1)-Pd(1)-P(1) 91.08(5), Pd(1)-Se(1)-C(12) 91.75(8),
N(2)-C(12)-Se(1) 125.31(19).
CDCl3, 25 ꢁC):
d
¼ ꢀ44.21. Anal. calc. for C14H19N6OPSePd (503.69):
C, 33.38; H, 3.80; N, 16.68. Found: C, 33.49; H, 4.02; N, 16.52 %.
3.12. X-ray crystallography
159.71 (d, JPeC ¼ 10.8 Hz, CSe), 148.12 (d, JPeC ¼ 3.2 Hz, C¼N), 134.57
(d, JPeC ¼ 11.7 Hz, o-Ph3P), 133.76 (C4), 131.06 (d, JPeC ¼ 2.7 Hz, p-
Ph3P), 129.66 (d, JPeC ¼ 50.5 Hz, ipso-Ph3P), 128.73 (C5), 128.38 (d,
JPeC ¼ 10.9 Hz, m-Ph3P), 127.11 (C7), 126.93 (C10), 124.12 (d,
JPeC ¼ 2.3 Hz, C3), 121. 79 (C6), 119.83 (C8), 106.76 (C1). 31P{1H}
Diffraction data were collected at 150 K using an Oxford
Diffraction Gemini E Ultra diffractometer, equipped with an EOS
CCD area detector and a four-circle kappa goniometer. For the data
collection the Mo source emitting graphite-monochromated Mo-
Ka
radiation (
l
¼ 0.71073 Å) was used. Data integration, scaling and
NMR (162 MHz, CDCl3, 25 ꢁC):
d
¼ 22.4. Anal. calc. for
empirical absorption correction was carried out using the CrysAlis
Pro program package [19]. The structure was solved using Direct
Methods (1) or Patterson Methods (6) and refined by Full-Matrix-
Least-Squares against F2. The non-hydrogen atoms were refined
anisotropically and hydrogen atoms were placed at idealised
positions and refined using the riding model. All calculations were
C30H24N3OPSePd (658.88): C, 54.69; H, 3.67; N, 6.38. Found: C,
54.76; H, 3.88; N, 6.18 %. X-ray quality crystals were obtained by
slow diffusion of Et2O into a CH2Cl2 solution of the compound.
3.9. [Pt(L1Se)(PPh3)] (7)
This was prepared as described above from trans-[PtCl2(PPh3)2]
(0.100 g, 0.126 mmol) and H2L1Se (0.037 g, 0.126 mmol). 0.061 g
(64%) of a yellow solid was obtained. 1H NMR (400 MHz, CDCl3, 25
Table 1
Crystal data and refinement details of compounds 1 and 6.
1
6
ꢁC):
d
¼ 9.59 (d, JPeH ¼ 11.4 Hz, 1 H, HC¼N), 8.16 (d, J ¼ 8.7 Hz, 1 H,
Empirical formula
Colour
C7H13SeN3
Colourless
218.16
Monoclinic
P21/n
10.1698(6)
8.4215(4)
11.0316(7)
111.079(7)
881.58(9)
4
1.644
4.200
440
0.13 ꢂ 0.15 ꢂ 0.16
3.13e29.47ꢁ
3943
C30H24N3OPdSeP
Orange
658.85
Monoclinic
P21/n
14.2882(8)
10.7668(7)
17.9064(10)
110.268(6)
2584.1(3)
4
1.693
2.218
1312
0.04 ꢂ 0.19v0.27
2.94e29.16ꢁ
12151
H8), 7.74e7.81 (m, 6 H, o-Ph3P), 7.67 (dd, J ¼ 8.0, 0.8 Hz, 1 H, H5),
7.63 (d, J ¼ 9.2 Hz, 1 H, H4), 7.41-7.53 (m, 10 H, m-Ph3P, p-Ph3P, H7),
7.26 (dt, J ¼ 7.3, 0.8 Hz,1 H, H6), 6.85 (d, J ¼ 9.2 Hz,1 H, H3), 4.91 (br.
Mr, g mol-1
Crystal system
Space group
a, Å
s, 2 H, NH2). 13C NMR (100 MHz, CDCl3, 25 ꢁC):
d
¼ 161.60 (d,
JPeC ¼ 9.8 Hz, ipso-Ph3P), 160.95 (C2), 145.86 (d, JPeC ¼ 2.6 Hz, C¼N),
134.62 (d, JPeC ¼ 11.2 Hz, o-Ph3P), 133.40 (C4), 131.03 (d,
JPeC ¼ 2.5 Hz, p-Ph3P), 130.36 (CSe), 129.76 (C9), 128.74 (C5), 128.20
(d, JPeC ¼ 11.1 Hz, m-Ph3P), 127.39 (C10), 127.17 (C7), 124.31 (C3),
122.30 (C6), 119.81 (C8), 107.50 (C1). 31P{1H} NMR (162 MHz, CDCl3,
b, Å
c, Å
b ꢁ
,
V, Å3
Z
Dcalc., g cm-3
25 ꢁC):
d
¼ 7.14 (JPteP ¼ 3562 Hz). Anal. calc. for C30H24N3OPSePt
m
, mmꢀ1
(747.55): C, 48.20; H, 3.24; N, 5.62. Found: C, 47.98; H, 3.16; N, 5.69 %.
F(000)
Crystal size, mm3
3.10. [Pd(L2Se)(PPh3)] (8)
q
range for data collection
Refl. collected
Independent refl.
Abs. corr.
Max. / min. trans.
Parameters
2058
5879
This was prepared as described above from trans-[PdCl2(PPh3)2]
(0.100 g, 0.142 mmol) and H2L2Se (0.035 g, 0.144 mmol). 0.055 g
(63%) of an orange solid was obtained. 1H NMR (400 MHz, CDCl3, 25
Multi-scan
1.00000/0.80997
109
0.0336
0.0477
Multi-scan
1.00000/0.47936
342
0.0432
0.0534
ꢁC):
d
¼ 8.28 (d, J ¼ 13.2 Hz, 1 H, HC¼N), 7.73-7.80 (m, 6 H, o-Ph3P),
R1 (all data)
wR2 (all data)
7.50-7.55 (m, 3 H, p-Ph3P), 7.43-7.49 (m, 6 H, m-Ph3P), 7.30 (dd,
J ¼ 7.9, 1.8 Hz, 1 H, H6), 7.24 (dt, J ¼ 8.6, 1.9 Hz, 1 H, H5), 6.69 (d,
Largest diff. peak / hole, e Åꢀ3
0.323/ꢀ0.390
0.487/-0.366

1662
P. Bippus et al. / Journal of Organometallic Chemistry 695 (2010) 1657e1662
ꢁ
ꢁ
ꢁ
ꢂ ꢁ
[3] T.R. Todorovic, A. Bacchi, D.M. Sladic, N.M. Todorovic, T.T. Bozic, D.
carried out using the program Olex2 [20]. Important crystallo-
graphic data and refinement details are summarised in Table 1.
ꢁ
ꢁ
ꢁ
D. Radanovic, N.R. Filipovic, G. Pelizzi, K.K. AnCelkovic, Inorg. Chim. Acta 362
(2009) 3813e3820.
[4] R. Huls, M. Renson, Bull. Soc. Chim. Belg. 65 (1956) 511e522.
[5] R. Huls, M. Renson, Bull. Soc. Chim. Belg. 65 (1956) 684e695.
[6] D.J. Fry, P.J. Keogh. GB1326597 assigned to Ilford Ltd. UK; 1973.
[7] A. Molter, F. Mohr, Coord. Chem. Rev. 254 (2010) 19e45.
[8] D. Gallenkamp, T. Porsch, A. Molter, E.R.T. Tiekink, F. Mohr, J. Organomet.
Chem. 694 (2009) 2380e2385.
Acknowledgements
F.M. gratefully acknowledges RETORTE GmbH for a generous
donation of selenium metal. We also thank the DFG for a grant to
purchase the diffractometer.
[9] D. Gallenkamp, E.R.T. Tiekink, F. Mohr, Phosphorus, Sulfur. Silicon 183 (2008)
1050e1056.
[10] A. Molter, F. Mohr. unpublished results.
Appendix. Supplementary data
[11] T.N. Tarkhova, L.E. Nikolaeva, M.A. Simonov, A.V. Ablov, N.V. Gerbeleu, A.
M. Romanov, Dokl. Akad. Nauk SSSR 214 (1974) 1326e1329.
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[13] S. Halder, S.M. Peng, G.H. Lee, T. Chatterjee, A. Mukherjee, S. Dutta, U. Sanyal,
S. Bhattacharya, New J. Chem. 32 (2008) 105e114.
[14] F. Fuge, C. Lehmann, F. Mohr, J. Organomet. Chem. 694 (2009) 2395e2401.
[15] J.C. Bruce, K.R. Koch, Acta Cryst. C64 (2008) m1em4.
[16] M. Kampf, R. Richter, J. Griebel, A. Weller, R. Kirmse, Z. Anorg, Allg. Chem. 631
(2005) 698e708.
Full crystallographic details of compounds 1 and 6 (CIF file format)
are available from the CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK
by quoting the deposition codes CCDC 765520 and 765521.
References
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ꢁ
ꢁ
ꢁ
ꢂ ꢁ
[1] T.R. Todorovic, A. Bacchi, N.O. Juranic, D.M. Sladic, G. Pelizzi, T.T. Bozic, N.
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