Triphenyl lead, tin and germanium coordination compounds derived from 9H-3-thia-1,4a,9-triaza-fluorene-2,4-dithione

Article abstract of DOI:10.1016/j.jorganchem.2007.11.040

Reactions of potassium 4-thioxo-3-thia-1,4a,9-triaza-fluorene-2-thiolate with Ph₃PbCl, Ph₃SnCl and Ph₃GeCl provided the corresponding metal pentacoordinated compounds 2-4. Addition of THF afforded their hexacoordinated derivatives (5-7). Adducts of 2 and 3 with DMSO (8, 10), pyridine (9, 11), Ph₃PO (12, 14) CH₃OH (13, 15), respectively were synthesized. Compound 2 afforded the H₂O adduct (16). In all cases the metal atom is chelated by the ligand through a covalent bond with S2 and a coordination bond with N1 forming four membered rings. Compounds were identified by ¹H, ¹³C, ¹⁵N, ¹¹⁹Sn and ²⁰⁷Pb. X-ray diffraction structures of 2, 3, 8, 9, 11, 14 and 16 were obtained.

Full text of DOI:10.1016/j.jorganchem.2007.11.040

Available online at www.sciencedirect.com
Journal of Organometallic Chemistry 693 (2008) 492–504
www.elsevier.com/locate/jorganchem
Triphenyl lead, tin and germanium coordination compounds
derived from 9H-3-thia-1,4a,9-triaza-fluorene-2,4-dithione
´
´
Adrian Pena-Hueso, Adriana Esparza-Ruiz, Iris Ramos-Garcıa,
˜
Angelina Flores-Parra *, Rosalinda Contreras *
Departamento de Quı´mica, Cinvestav, A.P. 14-740, CP 07000 Me´xico, D.F., Mexico
Received 9 November 2007; accepted 12 November 2007
Available online 3 January 2008
Abstract
Reactions of potassium 4-thioxo-3-thia-1,4a,9-triaza-fluorene-2-thiolate with Ph3PbCl, Ph3SnCl and Ph3GeCl provided the corre-
sponding metal pentacoordinated compounds 2–4. Addition of THF afforded their hexacoordinated derivatives (5–7). Adducts of 2
and 3 with DMSO (8, 10), pyridine (9, 11), Ph3PO (12, 14) CH3OH (13, 15), respectively were synthesized. Compound 2 afforded the
H2O adduct (16). In all cases the metal atom is chelated by the ligand through a covalent bond with S2 and a coordination bond with
N1 forming four membered rings. Compounds were identified by 1H, 13C, 15N, 119Sn and 207Pb. X-ray diffraction structures of 2, 3, 8, 9,
11, 14 and 16 were obtained.
Ó 2007 Elsevier B.V. All rights reserved.
Keywords: Organogermanium; Organotin; Organolead; 9H-3-thia-1,4a,9-triaza-fluorene-2,4-dithione; 207Pb NMR; 119Sn NMR
1. Introduction
[18,19]. Of additional interest in lead and tin coordination
compounds is the search for new ligands which could be
useful in detoxification therapies [20,21]. Germanium has
wide applications for fabrication of electronic components
[22], as chemotherapeutic agents of low mammalian toxic-
ity [23,24] and as radioprotective agents [25].
Compounds derived from benzimidazole have diverse
biocidales activities and pharmaceutical applications
[26–28]. In particular tricyclic benzimidazole derivatives
have been investigated as potential inhibitors of dihydrofo-
late reductase in the search for anticancer and antibacterial
agents [29–31] and for DNA intercalating agents [31].
We are currently investigating the chemistry of organo-
metallic compounds of the group 14 elements [1,2] and
particularly those coordinated to planar and aromatic mol-
ecules [3–8]. These ligands and the metal atoms provide
hypervalent metal atoms and versatile coordination modes.
Their rigid structures make them suitable models for the
study of weak interactions in the solid-state. Interest in
these coordination compounds is also based on the use of
multinuclear magnetic resonance techniques for their anal-
yses in solution.
The heavier elements of group 14 show rich coordina-
tion chemistry [9–12]. In addition tin compounds have
applications in industry, agriculture and medicine [13–17],
whereas the relevance of lead coordination compounds is
based on their application in pharmacology and toxicology
2. Results and discussion
Herein, we report the syntheses and characterization of
coordination compounds of triphenyl lead, tin, and germa-
nium with the new aromatic tetracyclic ligand: 9H-3-thia-
1,4a,9-triaza-fluorene-2,4-dithione 1a, Scheme 1.
The interest of a detailed structural analysis of the metal
coordination compounds derived from 1a is due to the fact
*
Corresponding authors. Tel.: +55 5061 3720; fax: +55 5061 3389
(A. Flores-Parra).
E-mail address: aflores@cinvestav.mx (A. Flores-Parra).
0022-328X/$ - see front matter Ó 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2007.11.040

A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
493
S
S
14 S
S
S
S
S
S
S
S
N
13
12
N
-
+
11
S
N
N
N
N
K
S
Ph
Ph
N
7
4
Ph
15
6
5
1
10
M
8
9
N
M
O
2
N
N
N
Ph
Ph
3
5 M = Pb
6 M = Sn
7 M = Ge
N
2 M = Pb Ph
3 M = Sn
4 M = Ge
1b
1a
H
Scheme 1. Structure of the 9H-3-thia-1,4a,9-triaza-fluorene-2,4-dithione
1a.
S
S
N
N
S
S
S
S
N
that a bidentate coordination of ligand to metal atoms
could occur in at least five different ways, see Scheme 2.
The potassium thiolate (1b) is the precursor of com-
pound 1a. Thiolate 1b is an aromatic tricyclic molecule pre-
pared from 2-aminobenzimidazole, CS2 and KOH in
DMF, it is a stable bright yellow solid, soluble in polar sol-
vents. The simple one-step synthesis of 1b, contrast with
the reported multistep and complex synthesis of a similar
compound derived from imidazole [32].
Reactions of potassium 4-thioxo-3-thia-1,4a,9-triaza-
fluorene-2-thiolate (1b) with Ph3PbCl, Ph3SnCl and
Ph3GeCl provided the corresponding metal pentacoordi-
nated compounds 2–4, Scheme 3. Addition of THF affor-
ded their hexacoordinated derivatives (5–7). Adducts of 2
and 3 with DMSO (8, 10), pyridine (9, 11), Ph3PO (12,
14) CH3OH (13, 15), respectively were synthesized. Com-
pound 2 gave the H2O adduct (16).
N
N
Ph
Ph
Ph
Ph
N
M
M
Ph
Ph
O
S
N
8 M = Pb
10 M = Sn
9 M = Pb
11 M = Sn
Me
Me
S
N
N
S
N
N
S
S
S
S
N
N
Ph
Ph
Ph
Ph
M
M
O
Ph
Ph
O
P
12 M = Pb
14 M = Sn
CH3
13 M = Pb
15 M = Sn
H
Ph
Ph
Ph
S
2.1. NMR studies
S
S
N
Compound 1a and the potassium thiolate 1b were char-
N
1
acterized by NMR. The assignment of the H and 13C sig-
Ph
Ph
N
Pb
O
nals of 1b was based on COLOC, HETCOR and COSY
Ph
16
H
H
N
N
Scheme 3.
N
S
S
S
Ph
Ph
experiments, Table 1. The structure of compound 1b was
also deduced from the 15N data (N1, d = À191.4; N3,
d = À157.4; and N10, d = À136.3 ppm) [33]. For com-
M
Ph
S
N
S
N
1
pound 1b, the H signal of H7 is found at higher frequen-
S
N
S
N
cies than the starting material due to the proximity of S14;
a similar effect in H4 is due to the presence of the N-lone
pair at N3, Scheme 1 and Table 1. The 13C spectrum shows
nine signals, two to higher frequencies that belong to the
sulfur ipso carbons. The one found at d = 194.1 ppm corre-
sponds to the thione carbon atom, whereas the signal of
C11 (d = 184.4 ppm) base of a thiolate group, indicates
that the charge is located at S15. Carbon atoms C8 and
C9 have different chemical shifts, the one adjacent to the
N3 with a lone pair appears at d = 143.7 ppm, whereas
C8 close to a substituted nitrogen atom gives a signal at
d = 130.9 ppm, [34]. Compound 1a has a proton located
at N3, as is deduced from the 13C signal of C9 which
appears at d = 129.3 ppm, and the C11 (193.0 ppm) and
S
S
Ph
Ph
M
Ph
Ph
N
M
N
Ph
Ph
S
N
S
N
S
N
S
N
S
S
N
N
M
M
Ph
Ph
Ph
Ph
Ph
Ph
Scheme 2. Five possible coordination modes of a triphenylmetal fragment
to ligand 1.

494
A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
Table 1
NMR 1H and 13C data of compounds 1, 1a, 2, 3, 8–11
S
S
S
13
2
13
S
N
13
S
S
N
7
4
11
7
4
11
7
4
11
S
8
9
N
N
S
8
N
N
S
8
9
6
5
N
N
6
5
6
5
Ph
N
M
2
2
9
Ph
H
1
1a
2 M = Pb; 3 M = Sn
2
4
5
6
7
8
9
11
13
i
o
m
p
1 (DMSO-d6)
150.5 118.1
7.55
1a (DMSO-d6) 148.3 113.6
7.53
147.6 120.0
7.87
150.0 118.2
7.59
149.7 118.8
7.53
147.7 118.7
7.78
10 (DMSO-d6) 150.8 118.2
7.63
150.6 118.0
7.78
117.7/7.55 126.9/7.41 122.9/7.24 117.7/9.00 131.0 142.8 186.0
7.55 7.41 7.24 9.00
151.2 117.6/7.56 126.9/7.41 122.9/7.25 117.7/9.02 131.4 142.6 188.6 193.5 141.7 136.3
7.56 7.41 7.25 9.02 7.85
126.8
7.40
125.2
7.39
127.4
7.59
126.9
7.41
126.8
7.10
126.9
7.51
126.6
7.43
127.0
7.41
122.3
7.22
129.0
7.55
124.9
7.50
122.6
7.23
123.3
6.93
124.0
7.40
122.3
7.25
123.1
7.24
117.3
130.9 143.7 184.4 194.1
8.92
118.3
8.95
117.8
8.99
117.3
8.92
117.7
8.72
117.4
9.01
117.5
9.09
118.0
9.15
131.2 129.3 193.0 194.8
2 (CDCl3)
8 (DMSO-d6)
9 (Py-d5)
131.0 142.8 176.0 185.9 155.6 137.4
7.98
131.3 143.4 183.2 193.2 159.5 136.2
7.88
131.2 143.4 181.0 190.0 158.8 137.1
7.96
130.8 141.9 178.3 187.0 139.0 136.9
8.04
131.6 143.7 185.1 193.4 143.7 136.6
8.03
131.7 143.9 183.7 192.5 143.9 137.1
8.04
136.5
7.89
130.5
129.9
7.55
130.5
7.64
130.2
7.22
128.5
7.45
128.4
7.48
130.3
7.51
130.0
7.55
128.7
7.47
7.40
130.1
7.46
129.5
7.00
129.5
7.42
129.0
7.46
129.6
7.49
129.2
7.40
129.5
7.45
3 (CDCl3)
11 (Py-d5)
13 CD3OD
15 CD3OD
C13 (194.1 ppm) chemical shifts which correspond to thi-
one groups.
dinated to the metal atom, as has been observed for hetero-
cycles thionates and diverse metal atoms [35]. The
resonances of 207Pb of compound 2 (d = À3.1 ppm) and
the 119Sn of compound 3 (d = À75.6 ppm) are characteris-
tic of tetracoordinated metal atoms, indicating that the
nitrogen coordination is weak and has little effect on their
chemical shifts [36–41]. The X-ray diffraction of com-
pounds 2 and 3 confirmed the nitrogen coordination as
we will discuss later. The high resolution mass spectra, is
in agreement with one ligand linked to the MPh3 fragment.
Solution of 2–4 in THF produced the hexacoordinated
derivatives 5–7 as is deduced from the NMR data, Table
4. The 13C NMR data (in THF-d8) indicate that com-
pounds 5–7 have similar structures. The 119Sn and 207Pb
spectra of compounds 5 and 6 showed an important shift
to lower frequencies with respect to compounds 2 and 3
in CDCl3, attributed to the THF coordination, Table 2.
The 207Pb spectrum of compound 2 in DMSO-d6 gives a
signal at d = À199.4 ppm characteristic of DMSO coordi-
nation and attributed to compound 8, Tables 2 and 3.
The 207Pb spectrum of 2 in pyridine-d6 gave a resonance
at d = À217.2 ppm assigned to the hexacoordinated pyri-
dine complex 9. In both cases the 207Pb signals were shifted
to lower frequencies by 196.3 and 214.1 ppm.
The reaction of compound 1b with triphenylmetal chlo-
rides (lead, tin and germanium) afforded the corresponding
pentacoordinated compounds 2–4, Scheme 3. The lead
compound 2 and its derivatives are very stable, whereas
the tin compounds were hydrolyzed in the presence of
moisture and the germanium compound 4 was decomposed
by the addition of Lewis bases even in anhydrous condi-
tions. Compounds 2 and 3 were characterized by NMR
in CDCl3, solvent in which 4 was insoluble, Tables 1–3.
Comparison of the 13C data of compounds 2 and 3 with
those of the neutral ligand 1a indicated that the metal is
bonded to S15, and it is assumed that the nitrogen is coor-
Table 2
NMR 207Pb and 119Sn data
Solvent
207Pb
119Sn
CDCl3
2
À3.1
3
À75.6
À125.5
À226.1
À231.8
À251.0
À180.2
THF-d8
DMSO-d6
Py-d5
THF-d8
CD3OH
5
À104.9
À199.4
À217.2
À214.5
À136.1
6
8
10
11
14
15
9
12
13

A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
495
Table 3
water to 2 previously dissolved in CHCl3 were unsuccess-
ful. An analogous tin water adduct from compound 3
was not obtained due to its hydrolysis.
n
Values of observed coupling constants J(13C–119Sn) or nJ(13C–207Pb) for
M–Ph groups
2
3
5
6
8
10
9
11
13
i
633.7
2.2. X-ray diffraction analyses
o
m
p
84.6
22.3
46.1 82.1 44.5 87.1 46.7 78.4 43.6 47.4
51.4 130.1 64.6
13.1
70.6 110.1
15.6
70.0
14.6
The X-ray diffraction analyses were performed for com-
pounds 2, 3, 8, 9, 11, 14 and 16. In all structures, the ligand
is bidentated, bonded to the metal through S15 and N10.
The confirmation of the nitrogen coordination to the metal
atom is based on the nitrogen–metal atom distance which is
shorter than the sum of the van der Waals radii and on the
orientation of the plane of the tricyclic fragment of the
molecule that allows the approach of the nitrogen lone pair
to the metal atom. In molecules lacking a nitrogen atom in
ortho position to a thiophenol, the ring plane is not aligned
with the S–M bond, as for example, in the solid state struc-
tures of thiophenoltriphenyl lead [42] and thionaphtoltri-
phenyl tin [43]. The coordination forms four membered
rings M–S–C–N with penta- and hexacoordinated triorga-
nyl tin or lead compounds. Some examples of these che-
lates for tin [44–46] and lead [47,48] are known. Selected
bond lengths and angles are in Table 5, and crystal data
and structure refinement in Tables 6 and 7.
Table 4
1H and 13C NMR data of compounds 5–7 (THF-d8)
S
13
S
7
4
11
S
8
9
N
N
Ph
Ph
6
5
N
2
M
Ph
THF
5M = Pb;
6M = Sn;
7M = Ge
C atom
5
6
7
Compound 2 has two molecules in the asymmetric
unit. The lead atoms are hexacoordinated, with four
2
149.6
148.7
148.6
4
120.2/7.78
127.8/7.63
124.8/7.48
118.6/9.03
132.3
144.5
179.6
189.6
159.2
120.4/7.75
127.9/7.44
125.2/7.33
118.4/8.93
132.0
143.8
176.9
187.6
140.4
123.4/7.59
128.6/7.46
127.5/7.41
117.5/9.04
130.5
137.8
183.2
193.2
137.5
covalent bonds and are coordinated intramolecularly to
˚
5
6
N
{N10 ? Pb16 = 3.093(7), N50 ? Pb56 = 3.162(7) A,
vwr = 3.90 A [49]} and to the S54 of another molecule,
P
7
˚
8
forming a polymer {Pb16Á Á ÁS54 3.607(3), Pb56Á Á ÁS14
9
P
˚
˚
3.497(3) A, vwr = 4.1 A [49]}, with the cooperation of
S12 and S52 p-interaction with one of the Pb-phenyl
groups [distances of S to ring centroids 3.485(5) and
11
13
i
o
138.5/8.15
130.9/7.54
130.3/7.38
138.0/8.01
129.6/7.39
130.5/7.36
134.3/7.59
128.0/7.39
129.4/7.21
˚
3.460(5) A], Fig. 1. The metal atoms do not have an ideal
m
p
octahedral geometry. A distortion is originated by the
angular tension of the four membered ring (C–S–M–N).
The angles N10–Pb16–C23 and N50–Pb56–C63 are
149.6(3)° and 147.5(3)°, respectively. The two sulfur atoms
are trans, with angles S15–Pb16–S54 173.60(7)° and S14–
Pb56–S55 173.37(8)°. An intermolecular p-stacking occurs
between the two aromatic tricycles [distances between cen-
When tin compound 3 was dissolved in DMSO, com-
pound 10 was formed (119Sn d = À226.1 ppm), while the
solution in pyridine gave compound 11
(
119Sn
˚
d = À231.8 ppm). From the NMR tubes, crystals of 8, 9
and 11 were obtained which were characterized by X-ray
diffraction.
When compounds 2 and 3 were dissolved in THF and an
excess of Ph3PO added, the corresponding adducts 12 and
14 were obtained (207Pb d = À214.5 and 119Sn d =
À 251.0 ppm), Table 2. Compound 12 was only character-
ized in solution, whereas 14 was analyzed by X-ray
diffraction.
The solution of compound 2 in methanol presents a
207Pb resonance at d = À 136.1 ppm, attributed to complex
13 whereas the 119Sn spectrum of the corresponding meth-
anol complex of 3, appears at d = À 180.2 ppm (15), Table
2. From the NMR tube of compound 13, a few crystals of
one molecule of 2 together with its water complex (16) were
obtained. Attempts to obtain compound 16 by adding
troids: 3.620(5) and 3.636(5) A], Fig. 2 [50].
Compound 3 has a pentacoordinated tin atom where the
˚
fifth bond is the N10–Sn coordination bond {3.088(3) A,
P
˚
vwr = 3.9 A, [49]}, Fig. 3. The geometry of the tin atom
is a distorted tbp. The wider angle is N10–Sn16–C23
[147.4(1)°], whereas the equatorial angles are C17–Sn16–
S15 109.2(2)°, S15–Sn16–C29 119.2(1)° and C17–Sn16–
C29 111.5(2)°. The solid-state structure of compound 3
presents intramolecular hydrogen bonds, between C–H34
and N3, and CH7 and S14 [51].
Addition of DMSO-d6 to 2 afforded compound 8. The
DMSO solutions gave two different polymorphs (8a and
8b). The X-ray diffraction analyses showed the lead atoms
hexacoordinated by the additional bonding of the DMSO
oxygen atom. The S15–Pb–O angle is 174.1(1)° in 8a and
171.3(1)° in 8b, Fig. 4. The bond lengths of N10 ? Pb

496
A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
Table 5
Selected bond lengths and angles for 2, 3, 8, 9, 11–13
2
3
8a
8b
9
11
12
13 molecule 1
13 molecule 2
N1–C2
N1–C13
N3–C2
1.42(1)
1.38(1)
1.28(1)
1.38(1)
1.434(5)
1.361(6)
1.296(5)
1.368(5)
1.280(6)
1.754(5)
1.752(5)
1.632(5)
1.727(4)
2.478(1)
2.130(4)
2.143(4)
2.131(4)
3.088(3)
1.437(7)
1.367(8)
1.289(7)
1.376(7)
1.284(7)
1.758(5)
1.742(6)
1.637(6)
1.721(5)
2.744(2)
2.176(5)
2.214(5)
2.185(5)
3.403(4)
2.619(4)
1.428(7)
1.366(7)
1.307(8)
1.364(8)
1.295(8)
1.751(5)
1.738(6)
1.640(6)
1.725(6)
2.684(2)
2.196(6)
2.211(6)
2.194(6)
3.400(5)
2.628(4)
1.44(1)
1.37(1)
1.30(1)
1.34(1)
1.28(1)
1.760(9)
1.74(1)
1.64(1)
1.71(1)
2.695(2)
2.17(1)
2.227(9)
2.171(9)
3.133(8)
2.825(7)
1.435(6)
1.358(6)
1.293(6)
1.356(7)
1.293(5)
1.756(5)
1.748(6)
1.640(5)
1.714(6)
2.596(1)
2.125(6)
2.146(5)
2.120(5)
3.112(4)
2.656(3)
1.444(4)
1.363(4)
1.296(4)
1.364(4)
1.291(5)
1.755(4)
1.740(3)
1.632(4)
1.714(3)
2.604(1)
2.131(3)
2.136(3)
2.130(3)
3.221(3)
2.452(2)
1.427(8)
1.38(1)
1.31(1)
1.356(9)
1.29(1)
1.757(7)
1.748(8)
1.630(7)
1.725(8)
2.615(2)
2.183(7)
2.209(7)
2.176(8)
3.170(5)
1.433(9)
1.371(9)
1.312(8)
1.356(8)
1.293(8)
1.768(7)
1.736(7)
1.631(8)
1.711(7)
2.718(2)
2.192(8)
2.194(8)
2.196(7)
3.485(5)
2.624(6)
N10–C2
N10–C11
S12–C11
S12–C13
S14–C13
S15–C11
M16–S15
M16–CA
M16–CB
M16–CC
M16–N10
M16–X35
1.29(1)
1.752(9)
1.733(9)
1.64(1)
1.727(7)
2.629(2)
2.179(8)
2.219(7)
2.175(8)
3.093(7)
3.607(3)
N10–C11–S15
C11–S15–M16
S15–M16–CA
S15–M16–CB
S15–M16–CC
CA–M16–CB
CA–M16–CC
CB–M16–CC
S15–M16–X35
CA–M16–X35
CB–M16–X35
CC–M16–X35
M16–X35–X36
122.5(7)
95.6(3)
103.8(2)
95.8(2)
103.3(2)
112.4(3)
127.0(3)
109.0(3)
173.60(7)
81.6(2)
122.3(3)
98.2(2)
119.2(1)
93.3(1)
109.2(1)
108.4(2)
111.5(2)
114.1(2)
123.8(4)
101.0(2)
103.1(1)
92.0(1)
124.0(4)
100.7(2)
94.8(1)
123.8(7)
95.1(3)
98.2(2)
91.7(2)
99.3(2)
111.9(3)
128.7(4)
115.3(4)
175.9(2)
78.1(3)
91.2(3)
82.1(3)
123.0(4)
96.7(2)
97.9(1)
92.2(1)
97.9(1)
112.5(2)
128.5(2)
115.5(2)
177.1(1)
79.6(2)
90.2(1)
82.7(1)
122.9(3)
99.8(1)
99.35(8)
85.7(1)
123.5(5)
97.6(3)
105.0(2)
94.8(2)
104.5(2)
109.4(3)
124.9(3)
113.4(3)
125.7(6)
103.5(2)
103.8(2)
87.2(2)
96.67(19)
112.5(3)
125.4(3)
118.7(3)
171.3(1)
81.4(2)
90.8(1)
94.9(1)
104.9(1)
114.8(2)
131.8(2)
108.5(2)
171.3(1)
80.4(2)
84.8(2)
83.7(2)
149.8(2)
94.7(1)
109.2(2)
123.9(2)
123.0(2)
174.1(1)
82.8(2)
85.5(2)
82.1(2)
121.1(2)
117.9(1)
125.7(1)
115.3(1)
174.44(5)
84.12(9)
88.9(1)
85.2(2)
70.5(2)
84.4(2)
85.6(2)
86.7(1)
145.9(1)
˚
˚
˚
are 3.403(4) A 8a and 3.400(5) A 8b, and those of S15–Pb
Addition of pyridine to the lead compound 2 afforded
adduct 9. In the crystal the lead atom is hexacoordinated,
Fig. 8. The sulfur and the pyridine nitrogen are trans [S–
Pb–N angle is 175.9(2)° and bond lengths are N35–Pb
˚
are 2.744(2) A (8a) and 2.684(2) A (8b). Both, the N10–
Pb and S–Pb bond lengths are longer in 8 than in 2
˚
[3.093(7) and 2.629(2) A] which could be the effect of a
strong O–Pb coordination bond [Pb–O 2.619(4) A 8a,
Pb–O 2.628(4) A 8b], Fig. 4.
˚
˚
2.825(7) and S–Pb 2.695(2) A]. The planes of the pyridine
˚
and the ligand are orthogonal. One Pb–Ph group is aligned
with the S–Pb–N bonds, giving two hydrogen bonds
In the cell of polymorph 8a, dimers are formed by bifur-
cated C–HÁ Á ÁOÁ Á ÁH–C hydrogen bonds [2.81(6) and
˚
˚
[CH28Á Á ÁS15 2.71 A and CH24Á Á ÁN35(p) 2.63 A] [51],
Fig. 8. One molecule of pyridine (not shown) cocrystallized
with 9.
˚
2.59(7) A] of the coordinated DMSO group, the angle
Pb–O–S is 121.1(2)°. The sulfur atom of the coordinated
DMSO is pyramidal [O35–S36–C37 angle is 106.3(3)° and
O35–S36–C38 is 104.7(3)°], Fig. 5.
The solid-state structure of the tin compound 11 is iso-
morphous with that found for the analogous lead com-
˚
The second polymorph (8b) forms dimers by two bifur-
pound 9, Fig. 9. The Sn–N 2.656(3) A and Sn–S
˚
˚
cated C–HÁ Á ÁNÁ Á ÁH–C bonds (2.49 and 2.53 A), Fig. 6.
2.596(1) A bond distances are shorter than in compound
The oxygen has some sp character as is deduced from the
open angle Pb–O35–S36 149.8(2)°. A polymer is formed
by p-stacking between the tricycles, Fig. 7.
9. One of the Sn–Ph groups is aligned with S15–Sn–N35
bonds and its ortho-protons form hydrogen bonds with
˚
˚
S15 (2.61 A) and N35 (2.56 A). The other two phenyl

A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
497
Table 6
Crystal and data collection parameters of compounds 2, 3 and 8
Compound
2
3
8a
8b
Formula
Formula weight
Temperature (K)
C27H19N3PbS3
688.87
293
0.71073
Triclinic
C27H19N3S3Sn1
600.36
293
0.71073
Triclinic
C29H25N3OPbS4
767
293
0.71073
Monoclinic
P21/c
15.3021(2)
10.63410(10)
18.0650(2)
90
97.3826(6)
90
2915.24(6)
4
1.747
6.10
C29H25N3OPbS4
767
293
0.71073
Monoclinic
C2/c
25.5478(3)
11.9678(2)
19.1624(2)
90
101.2913(7)
90
5745.52(13)
8
1.773
6.19
˚
Wavelength (A)
Crystal system
Space group
ꢀ
ꢀ
P1
P1
˚
a (A)
13.1004(2)
13.8576(2)
15.6071(2)
71.6889(6)
71.3255(6)
84.7972(6)
2548.08(6)
4
9.7456(2)
10.0928(3)
13.5582(4)
92.382(2)
93.042(2)
109.8716(15)
1249.89(6)
2
˚
b (A)
˚
c (A)
a (°)
b (°)
c (°)
3
˚
Volume (A )
Z
Dcalc (Mg/m3)
1.796
6.89
1.595
1.29
l (mmÀ1
)
Absorption correction
Tmaximum, Tminimum
F(000)
Multiscan
0.5, 0.21
1328
SADABS
Multiscan
0.16, 0.09
1496
SADABS
0.94, 0.68
600
0.54, 0.4
2992
Crystal size (mm)
Crystal color
h Range
0.3 Â 0.22 Â 0.1
0.25 Â 0.2 Â 0.05
0.5 Â 0.38 Â 0.3
0.3 Â 0.15 Â 0.1
Yellow
Yellow
Yellow
Yellow
1.55–28.71
À17 6 h 6 17,
À18 6 k 6 18,
À16 6 l 6 21,
51706
1.51–28.67
À12 6 h 6 12,
À13 6 k 6 11,
À18 6 l 6 18,
13123
2.27–28.71
À19 6 h 6 20,
À13 6 k 6 14,
À24 6 l 6 24,
58463
1.62–28.69
À33 6 h 6 33
À16 6 k 6 14
À25 6 l 6 25
52064
Index range
Reflections collected
Independent reflections
Rint
13105
0.095
6278
0.062
7532
0.116
7401
0.088
Completeness to h (°)
Observed reflections
Goodness-of-fit on F2
Final R1
28.13, 99.8%
6289
1.04
0.036 (I > 3.0r)
0.042
26.66, 98.3%
3962
1.07
0.038 (I > 3.0r)
0.044
28.71, 99.7%
4183
1.06
0.027 (I > 3.0r)
0.028
28.69, 99.8%
4075
1.02
0.024 (I > 3.0r)
0.028
Final wR2
Fig. 2. Intermolecular p-stacking in 2.
Tin compound 14 is coordinated to the oxygen atom of
the triphenylphosphine oxide. The oxygen O35 and the sul-
Fig. 1. Asymmetric unit of compound 2. A polymer is formed by
intermolecular S ? Pb coordination and S ? p interactions.
˚
˚
fur S15 are trans [O–Sn 2.452(2) A and S–Sn 2.604(1) A].
˚
groups lie almost in the equatorial plane. An ortho proton
The Sn–N10 coordination bond length is 3.221(3) A. Angle
(H30) of one of these groups forms bifurcated hydrogen
S15–Sn–O35 is 174.44(5)° and Sn–O35–P36 is 145.9(1)°.
The phosphorus atom is tetrahedral, Fig. 10.
Compound 16 was obtained from a solution of 2 in wet
methanol. There are two different lead molecules in the cell,
˚
˚
bonds with N3 (2.91 A) and N10 (2.76 A). A molecule of
pyridine (not shown in Fig. 9) co-crystallized with 11 (see
Table 7).

498
A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
one is compound 2, whose structural data are similar to
that found in the crystal of 2, Table 5. The other is com-
pound 16, which has a water molecule coordinated to the
lead, in trans position to the sulfur atom, Fig. 11. In com-
Another intermolecular association between two molecules
of compound 16 is produced by hydrogen bonds between
one proton of a coordinated water molecule with the oxy-
gen of a crystallization water molecule, whose proton is in
turn coordinated to N43 of another molecule of 16, Fig. 14.
˚
pound 16, the distance between N50 and Pb56 is 3.485(5) A
˚
and the bond lengths are S55–Pb56 [2.718(2) A] and
˚
O75–Pb56 [2.624(6) A]. The effect of the water strong coor-
dination is observed in the lengths of N–Pb and S–Pb
bonds which are longer in 16 than in the compound 2 co-
crystallized with 16 [S15–Pb16 2.615(2) and N10–Pb16
˚
3.170(5) A].
In the structure of 16, one of the Pb-phenyl groups is
aligned with the axis S–Pb–O, in such a way that the o-phe-
˚
nyl protons form hydrogen bonds with S55 (2.86 A) and
˚
O75 (2.40 A), Fig. 12. Bifurcated p-interactions are repre-
sented in Fig. 13, they are formed between C45 of a mole-
˚
cule of 16 and C2 of a molecule of 2 [3.38(1) A] [50] and the
˚
C45H proton with the p electrons of C17 (2.886 A) [51].
Fig. 5. Dimer formed in polymorph 8a by C–HÁ Á ÁO hydrogen bonds.
Fig. 3. Solid-state structure of compound 3. The tin has a distorted tbp
geometry with N10 and C23 as the apical atoms. The N ? Sn coordina-
tion and two intramolecular hydrogen bonds are shown.
Fig. 6. Dimer formed in polymorph 8b.
Fig. 4. Solid-state structure of polymorphs 8a (left) and 8b (right).

A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
499
˚
Fig. 7. In 8b dimers form a polymer by p-stacking [distance N1Á Á ÁC5 3.418(8) A].
˚
and C–H31Á Á ÁC18 p-interaction (2.8 A) marked as C fur-
ther stabilize the dimeric structure.
3. Summary
Metathesis reactions of the new tricyclic and polyfunc-
tional compound potassium 4-thioxo-3-thia-1,4a,9-triaza-
fluorene-2-thiolate with Ph3PbCl, Ph3SnCl and Ph3GeCl
provided metal pentacoordinated compounds, by bidentate
coordination of the ligand. The products, in the presence of
Lewis bases, gave a series of hexacoordinated compounds.
Lead compounds are very stable to open air manipulations,
whereas tin compounds are susceptible to hydrolysis. The
germanium compound 4 was very reactive to moisture
and was decomposed by addition of Lewis bases even in
dry conditions. 119Sn and 207Pb NMR data were funda-
mental for evaluation of metal atom coordination in
solution, which was also confirmed in the solid-state by
X-ray diffraction. In all compounds, the ligand prefers
bonding with the metal atoms through S15 which allows
a weak coordination of N10 forming a four membered
metallacycle.
Fig. 8. Solid-state structure of compound 9.
4. Experimental
4.1. General comments
Vacuum line techniques were employed for all manipu-
lations of air and moisture sensitive compounds. THF was
dried by distillation from sodium–benzophenone under
nitrogen atmosphere prior to use. Dry DMSO-d6, pyri-
dine-d5, CD3OD, THF-d8 and organolead, organotin
and organogermanium were purchased from Aldrich and
used without further purification. The melting points were
obtained on a Mel-Temp II apparatus and are uncor-
rected. Mass spectra in the EI mode were recorded at
20 eV on a Hewlett–Packard HP 5989 spectrometer. High
resolution mass spectra were obtained by LC/MSD TOF
on Agilent Technologies instrument with APCI as ioniza-
tion source. Elemental analyses were performed on Eager
300 equipment. NMR spectra were obtained on a Jeol
GSX-270, Jeol Eclipse 400 MHz and Bruker Advance
300 MHz.
Fig. 9. Solid-state structure of compound 11.
An interesting fact is observed in the co-crystal of 2 with
16. Two molecules of 2 form a dimer by intermolecular
˚
p-interactions (3.71 A) between carbon atoms C29–C30
of two Pb–Ph groups marked as A in Fig. 15. The short dis-
P
˚
˚
tances (3.81–3.89 A, vwr = 4.1 A) between the Pb atoms
and the p electrons of the C31–C32 bond, marked as B

500
A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
Table 7
Crystal and data collection parameters of compounds 9, 11, 14 and 16
9
11
14
16
Formula
Formula weight
Temperature (K)
2(C32H24N4PbS3) Á C5H5N 2(C32H24N4SnS3) Á C5H5N C45H34N3OPS3Sn C27H21N3OPbS3 Á C27H19N3PbS3 Á CH4O Á H2O
1615.04
1438.02
293
878.65
1445.8
293
293
293
˚
Wavelength (A)
0.71073
Monoclinic
P21/c
0.71073
Monoclinic
P21/c
0.71073
Monoclinic
P21/n
0.71073
Triclinic
Crystal system
Space group
ꢀ
P1
˚
a (A)
9.94200(10)
23.8990(3)
16.8289(2)
90
124.2940(10)
90
9.93460(10)
23.8530(4)
16.8665(2)
90
125.0000(10)
90
12.03330(10)
10.77470(10)
30.8810(3))
90
93.6861(4)
90
13.2869(2)
14.2793(3)
16.0323(5)
91.6002(8)
90.9159(8)
114.5976(13)
2763.39(12)
2
˚
b (A)
˚
c (A)
a (°)
b (°)
c (°)
3
˚
V (A )
3303.48(8)
2
3273.84(8)
2
3995.60(6)
4
Z
Dcalc. (Mg/m3)
1.624
1.459
1.461
1.737
l (mmÀ1
)
5.327
1.00
0.88
6.359
Absorption correction
Tmaximum, Tminimum
F(000)
Multiscan
0.45, 0.26
1580
SADABS
SADABS
SADABS
0.82, 0.59
1452
0.79, 0.89
1784
0.73, 0.5
1404
Crystal size (mm)
Crystal color
h range
0.28 Â 0.25 Â 0.15
0.25 Â 0.25 Â 0.2
0.5 Â 0.38 Â 0.3
0.25 Â 0.1 Â 0.05
Yellow
Yellow
Yellow
Yellow
1.69–28.71
À13 6 h 6 13,
À32 6 k 6 32,
À21 6 l 6 22,
37493
1.70–30.51
À11 6 h 6 13,
À33 6 k 6 33,
À24 6 l 6 23,
36297
1.32–30.14
À19 6 h 6 20,
À13 6 k 6 14,
À24 6 l 6 24,
79084
3.09–30.49
À18 6 h 6 18
À15 6 k 6 20
À21 6 l 6 22
49813
Index range
Reflections collected
Independent reflections 8511
9162
10836
15337
Rint
0.116
0.082
0.101
0.061
Completeness to h (°)
Observed reflections
Goodness-of-fit on F2
Final R1
28.71, 99.6%
3202
1.08
0.036 (I > 2.5r)
0.038
25.02, 99.5%
3528
1.09
0.033 (I > 2.5r)
0.038
28.33, 99.6%
4575
1.05
0.027 (I > 2.5r)
0.029
25.00, 99.4%
6311
1.03
0.033 (I > 2.5r)
0.034
Final wR2
Coordination compounds 5–16 were submitted to high
resolution mass analyses, however all compounds dissoci-
ate in the equipment and the molecular masses were not
obtained
4.2. Syntheses
4.2.1. Potassium 4-thioxo-3-thia-1,4a,9-triaza-fluorene-
2-thiolate (1b)
To a solution of 20 g (150 mmol) of 2-aminobenzimidaz-
ole in 200 mL of DMF, powdered KOH was added (28.1 g,
150 mmol, 90%). The reaction mixture was stirred for 4 h.
Then 20 mL of CS2 were added (167 mmol) and stirring
continued. After 12 h, CHCl3 (1 L) was added and then
the precipitate filtered. The solid was washed with water
(500 mL), left to dry and dissolved in acetone and set aside.
After 15 days, a microcrystalline yellow powder was
obtained (17.2 g, 35%), which was the dihydrate of 1.
Dec. at 300 °C. Anal. Calc. for C9H4N3S3 K Á 2H2O: C,
33.21; H, 2.48; N, 12.91; S 29.55. Found: C, 33.58; H,
2.48; N, 13.07; S, 29.92%.
4.2.2. 9H-3-Thia-1,4a,9-triaza-fluorene-2,4-dithione (1a)
Compound 1b (3 g, 9.2 mmol) was dissolved in THF
(50 mL) and HCl (aq, 36%, 3 mL, 35 mmol) was added.
The precipitate was filtered and left to dry to give a yellow
powder. (2.2 g, 95%). M.p.: 158–162 °C. MS (EI, 20 eV):
[M+] 251(3) m/z. Anal. Calc. for C9H5N3S3: C, 43.01; H,
2.01; N, 16.72; S 38.27. Found: C, 43.18; H, 1.94; N,
16.61; S, 37.66%.
Fig. 10. Solid-state structure of compound 14.

A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
501
Fig. 11. View of the asymmetric unit of 16 co-crystallized with one molecule of 2, one of methanol and one of water.
Fig. 14. Intermolecular association of two molecules of 16 by two
hydrogen bonds of two water molecules.
Fig. 12. Structure of compound 16 showing the intramolecular hydrogen
bonds and the N–Pb coordination bond.
4.2.3. Triphenyllead 4-thioxo-3-thia-1,4a,9-triaza-fluorene-
2-thiolate (2)
Compound 1 (500 mg, 1.54 mmol) was dried at 200 °C
in a vacuum line for 2 h. Then it was dissolved in dried
THF (50 mL) and Ph3PbCl was added (730 mg,
1.54 mmol) and stirred overnight. The mixture was set
aside for 6 h in order to separate the liquid from the solid,
then the liquid was evaporated to give a yellow solid
(895 mg, 84%). M.p.: 183–186 °C. Suitable crystals for
X-ray were grown from CHCl3 or THF solutions. HRMS
(TOF), (C27H19N3S3Pb-H)+ 690.0580 amu. Found:
690.0579 (error = 0.19 ppm). Anal. Calc. for C27H19N3-
S3Pb: C, 47.08; H, 2.78; N, 6.10; S 13.96. Found: C,
46.86; H, 2.80; N, 5.95; S, 13.26%.
4.2.4. Triphenyltin 4-thioxo-3-thia-1,4a,9-triaza-fluorene-2-
thiolate (3)
The same procedure as for compound 2 was used for 3.
Compound 1 (500 mg, 1.54 mmol) and Ph3SnCl (594 mg,
Fig. 13. Intermolecular p-interactions in the co-crystal of compounds 16
and 2.

502
A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
ture of compound 2, with 2 equiv. of ligand 1 in DMSO set
aside for three months, pale yellow crystals of the poly-
morph 8a were obtained, M.p.: 154 °C. Both polymorphs
were submitted to X-ray diffraction analyses.
4.2.8. (N–Pb)-pyridine-4-thioxo-3-thia-1,4a,
9-triaza-fluorene-2-thiolate-triphenyllead (9)
A solution of 50 mg of 2 (72.6 lmol) dissolved in 0.4 mL
of pyridine-d5 produced compound 9 which was studied by
NMR. After one day yellow crystals were formed that
were used for X-ray diffraction analyses. Decomp. at
130 °C.
4.2.9. (O–Sn)-dimethylsulfoxide-4-thioxo-3-thia-1,4a,9-
triaza-fluorene-2-thiolate-triphenyltin (10)
A solution of 3 (50 mg, 83.3 lmol) dissolved in
0.4 mL of DMSO-d6 gave compound 10, the yellow solu-
tion was submitted to NMR analyses, no crystals were
obtained.
Fig. 15. Dimer of compound 2 formed in the co-crystal of 2 and 16, by
4.2.10. (N–Sn)-pyridine-4-thioxo-3-thia-1,4a,
9-triaza-fluorene-2-thiolate-triphenyltin (11)
˚
cooperative p-interactions between C29Á Á ÁC30 (3.71 A), marked as A,
˚
between Pb and C32–C31 (3.81 and 3.89 A) B, and between H31 and C18
˚
(2.83 A), C.
A solution of 3 (50 mg, 83.3 lmol) dissolved in 0.4 mL
of pyridine-d5, produced compound 11, which was submit-
ted to NMR analyses. After three days yellow crystals were
formed in the tube, which were suitable for X-ray diffrac-
tion analyses. M.p.: 175–176 °C.
1.54 mmol) afforded a microcrystalline yellow powder
(740 mg, 80%). M.p.: 166–168 °C. Crystals for X-ray dif-
fraction were grown from a solution in THF. HRMS
(TOF) (C27H19N3S3Sn-H)+ 601.9835 amu. Found:
601.9854 (error = 3.01 ppm).
4.2.11. (O–Pb)-triphenyphosphine-oxide-4-thioxo-3-thia-
1,4a,9-triaza-fluorene-2-thiolate-triphenyllead (12) and
(O–Sn)-triphenyphosphine-oxide-4-thioxo-3-thia-1,4a,9-
triaza-fluorene-2-thiolate-triphenyltin (14)
4.2.5. Triphenylgermanium 4-thioxo-3-thia-1,4a,
9-triaza-fluorene-2-thiolate (4)
To a solution of compound 2 (20 mg, 29 lmol) in
The same procedure as for compound 2 was used for 4.
Compound 1 (500 mg, 1.54 mmol) and Ph3GeCl (521 mg,
1.54 mmol) afforded a yellow powder (570 mg, 67%).
Dec. at 160 °C. HRMS (TOF) (C27H19N3S3Ge–H)+
556.0025. Found: 556.0030 (error = 0.78 ppm).
CDCl3 or 3 (20 mg, 33.2 lmol) in THF, approx.
10 equiv. of Ph3PO were added (81 mg, 290 lmol). The
yellow solutions were submitted to NMR. An equimolar
mixture of 3 (20 mg, 33.2 lmol) and Ph3PO (9.2 mg,
33.2 lmol) in 0.4 mL of THF-d8 afforded pale yellow
crystals suitable for X-ray diffraction analyses. M.p.:
154–158 °C.
4.2.6. (O–Pb)-tetrahydrofurane-4-thioxo-3-thia-1,4a,
9-triaza-fluorene-2-thiolate-triphenyllead (5),
(O–Sn)-tetrahydrofurane-4-thioxo-3-thia-1,4a,
9-triaza-fluorene-2-thiolate triphenyltin (6)
(O–Ge)-tetrahydrofurane-4-thioxo-3-thia-1,4a,
9-triaza-fluorene-2-thiolate triphenylgermanium (7)
Solutions of 20 mg of 2 (29.0 lmol), 3 (33.2 lmol) or 4
(36.1 lmol) in 0.4 mL of dry THF-d8 were analyzed by
NMR. Evaporation of the solvent afforded compounds 2
and 3, whereas compound 4 decomposes on standing or
by solvent evaporation.
4.2.12. (O–Pb)-methanol-4-thioxo-3-thia-1,4a,9-triaza-
fluorene-2-thiolate-triphenyllead (13) and (O–Pb)-water-4-
thioxo-3-thia-1,4a,9-triaza-fluorene-2-thiolate-triphenyllead
(16)
Complex 13 was prepared by dissolution of compound 2
(5 mg, 7.3 lmol) in CD3OD, and characterized by NMR
analyses. From the NMR tube pale yellow crystals were
obtained for X-ray diffraction analyses which corre-
sponded to a co-crystal of compounds 16 and 2. M.p.:
138–146 °C.
4.2.7. (O–Pb)-dimethylsulfoxide-4-thioxo-3-thia-1,4a,
9-triaza-fluorene-2-thiolate-triphenyllead (8)
A solution of 2 (50 mg, 72.6 lmol) dissolved in 0.4 mL
of DMSO-d6 afforded compound 8, which was analyzed
by NMR. After two weeks pale yellow crystals (8b) were
formed in the NMR tube. M.p.: 139–141 °C. From a mix-
4.2.13. (O–Sn)-methanol-4-thioxo-3-thia-1,4a,9-triaza-
fluorene-2-thiolate- triphenyltin (15)
Complex 15 was prepared from a solution of compound
3 (5 mg, 8.3 lmol) in 0.4 mL of CD3OD and characterized
by NMR analyses.

A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
503
[11] T. Sato, in: E.W. Abel, F.G.A. Stone, G. Wilkinson (Eds.),
Comprehensive Organometal. Chem. II, vol. 11, Pergamon Press,
1995, p. 389 (Chapter 8).
4.3. X-ray structural analysis of compounds 2, 3, 8, 9, 11, 14
and 16
[12] J.T. Pinhey, in: E.W. Abel, F.G.A. Stone, G. Wilkinson (Eds.),
Comprehensive Organometal. Chem. II, vol. 11, Pergamon Press,
1995, p. 461 (Chapter 11).
[13] A.G. Davies, Organotin Chemistry, VCH, 1997.
[14] R.V. Singh, S.C. Joshi, A. Gajraj, P. Nagpal, Appl. Organometal.
Chem. 16 (2002) 713.
[15] S. Tabassum, C. Pettinari, J. Organomet. Chem. 691 (2006) 1761.
[16] C. Pellerito, L. Nagy, L. Pellerito, A. Szorcsik, J. Organomet. Chem.
691 (2006) 1733.
Data were measured on a Nonius Kappa CCD instru-
ment with CCD area detector using graphite-monochro-
mated Mo Ka radiation at 293 K. Intensities were
measured using u + x scans. All structures were solved
using direct methods with SHELX-97 [52], except compound
2 which was solved using SIR-2002 [53]. The refinement for
all structures (based on F2 of all data) was performed by
full matrix least-squares techniques with crystals 12.84 [54].
All non-hydrogen atoms were refined anisotropically, all
C–H hydrogen atoms were placed on ideal positions, and
the O–H of 16 were located in the difference map and
allowed to ride on their respective atoms.
´
[17] F. Huber, G. Roge, L. Carl, G. Atassi, F. Spreafico, S. Filippeschi,
R. Barbieri, A. Silvestri, E. Rivarola, G. Ruisi, F. Di Bianca, G.
Alonzo, J. Chem. Soc., Dalton Trans (1985) 523.
[18] J.S. Magyar, T.-C. Weng, C.M. Stern, D.F. Dye, B.W. Rous, J.C.
Payne, B.M. Bridgewater, A. Mijovilovich, G. Parkin, J.M. Zaleski,
J.E. Penner-Hahn, H.A. Godwin, J. Am. Chem. Soc. 127 (2005) 9495.
[19] Agency for Toxic Substances and Disease Registry. (<http://
www.atsdr.cdc.gov>).
[20] A.B. Ghering, L.M.M. Jenkins, B.L. Schenck, S. Deo, R.A. Mayer,
M.J. Pikaart, J.G. Omichinski, H.A. Godwin, J. Am. Chem. Soc.
127 (2005) 3751.
[21] R.J. Andersen, R.C. diTargiani, R.D. Hancock, C.L. Stern, D.P.
Goldberg, H.A. Godwin, Inorg. Chem. 45 (2006) 6574.
[22] R.R. Moskalyk, Miner. Eng. 17 (2004) 393.
[23] K. Rubina, E. Abele, P. Arsenyau, R. Abele, M. Veveris, E. Lukevics,
Met. Based Drugs 8 (2001) 85.
Acknowledgements
Financial support from Conacyt-Mexico and Cinvestav
is acknowledged as well as Conacyt-Mexico scholarships
for A.E.-R. and A.P-H. The authors are grateful to A.
Paz-Sandoval and J. Guthrie for valuable comments
discussions.
[24] G.B. Gerber, A. Leonard, Mutat. Res. 387 (1997) 141.
Appendix A. Supplementary material
´
´
[25] G. Rima, J. Satge, R. Dagiral, C. Lion, H. Sentenac-Roumanou, M.
Fatome, V. Roman, J.-D. Laval, Eur. J. Med. Chem. 6 (1999) 49.
[26] W.L. Drew, R.C. Miner, G.I. Marousek, S. Chou, J. Clin. Virol. 37
(2006) 124.
CCDC 666737, 666738, 666739, 666740, 666741,
666742, 666743 and 666744 for compounds 2, 3, 8a, 8b,
9, 11, 12 and 16. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre
via www.ccdc.cam.ac.uk/data_request/cif. Supplementary
data associated with this article can be found, in the online
version, at doi:10.1016/j.jorganchem.2007.11.040.
[27] I. Omar, T.M. O’Neill, S. Rossall, Plant Pathol. 55 (2006) 92.
[28] A. Joubert, X.-W. Sun, E. Johansson, C. Bailly, J. Mann, S. Neidle,
Biochemistry 42 (2003) 5984.
[29] A.V. Dolzhenko, W.-K. Chui, J. Heterocyclic Chem. 43 (2006) 95.
[30] A.V. Dolzhenko, W.-K. Chui, A.V. Dolzhenko, Heterocyclic Chem.
43 (2006) 1513.
[31] A.D. Settimo, G. Primofiore, F.D. Settimo, A.M. Marini, S. Taliani,
S. Salerno, L.D. Via, J. Heterocyclic Chem. 40 (2003) 1091.
[32] F. Saczewski, J. Saczewski, M. Gdaniec, J. Org. Chem. 68 (2003)
4791.
References
[33] M. Witanowski, L. Stefaniak, Annu. Rep. NMR Spectrosc. 18 (1986)
67.
[1] C. Camacho-Camacho, R. Contreras, H. No¨th, M. Bechmann, A.
Sebald, W. Milius, B. Wrackmeyer, Magn. Reson. Chem. 40 (2002)
31.
´
´
´
[34] A.E. Cisneros-Gomez, A. Ramos-Organillo, J. Hernandez-Dıaz, J.
´
Nieto-Martınez, R. Contreras, S.E. Castillo-Blum, Heteroatom
´
´
´
[2] C. Camacho-Camacho, V.M. Jimenez-Perez, J.C. Galvez-Ruiz, A.
Flores-Parra, R. Contreras, J. Organomet. Chem. 691 (2006) 1590.
[3] C. Camacho-Camacho, H. Tlahuext, H. No¨th, R. Contreras,
Heteroatom. Chem. 9 (1997) 321.
Chem. 11 (2000) 392.
[35] E.S. Raper, Coord. Chem. Rev. 153 (1996) 199.
[36] B. Wrackmeyer, K. Horchler, Annu. Rep. NMR Spectrosc. 22 (1989)
249.
´
[4] M.P. Fialon, N. Andrade-Lopez, N. Barba-Behrens, R. Contreras,
[37] P.J. Smith, A.P. Tupciauskas, Annu. Rep. NMR Spectrosc. 8 (1978)
291.
Heteroatom Chem. 9 (1998) 637.
´
´
[5] R. Contreras, V.M. Jimenez-Perez, C. Camacho-Camacho, M.
[38] B. Wrackmeyer, Annu. Rep. NMR Spectrosc. 38 (1999) 203.
[39] B. Wrackmeyer, Annu. Rep. NMR Spectrosc. 16 (1985) 73.
[40] R. Hani, R.A. Geanangel, Coord. Chem. Rev. 44 (1982) 229.
[41] J. Holecek, M. Nadvornik, K. Handlir, A. Lycka, J. Organometal.
Chem. 241 (1983) 177.
´
Guizado-Rodrıguez, B. Wrackmeyer, J. Organomet. Chem. 604
¨
(2000) 229.
´
´
´
[6] V.M. Jimenez-Perez, C. Camacho-Camacho, M. Guizado-Rodrıguez,
¨
H. No¨th, R. Contreras, J. Organometal. Chem. 614/615 (2000) 283.
[7] V.M. Jimenez-Perez, A. Ariza-Castolo, A. Flores-Parra, R. Contre-
´
´
[42] M.G. Begley, G. Gaffney, P.G. Harrison, A. Steel, J. Organometal.
Chem. 289 (1985) 281.
ras, J. Organometal. Chem. 691 (2006) 1584.
´
´
[8] V.M. Jimenez-Perez, C. Camacho-Camacho, A. Ramos-Organillo,
[43] A. Kalsoom, M. Mazhar, S. Ali, M.F. Mahon, K.C. Molloy, M.I.
Chaudry, Appl. Organometal. Chem. 11 (1997) 47.
[44] Y. Shi, C. Ma, R. Zhang, J. Organometal. Chem. 691 (2006) 1661,
and references cited there.
´
R. Ramırez-Trejo, A. Pena-Hueso, R. Contreras, A. Flores-Parra, J.
˜
Organometal. Chem. 692 (2007) 5549.
[9] Saul Patai, The Chemistry of Functional Groups: The Chemistry of
Organic Germanium, Tin and Lead Compounds, vol. 19, Wiley, 1995
(Chapter 19).
´
´
[45] J.S. Casas, A. Castineiras, E.G. Martınez, A.S. Gonzalez, A. Sordo,
Polyhedron 16 (1997) 795.
[46] C. Ma, Y. Shi, Q. Jiang, Heteroatom Chem. 16 (2005) 69.
[10] J. Parr, in: J.A. MacCleverty, T.J. Meyer (Eds.), Comprehensive
Coordination Chem. II, vol. 3, Elsevier Pergamon, 2004, p. 545.

504
A. Pen˜a-Hueso et al. / Journal of Organometallic Chemistry 693 (2008) 492–504
[47] M. Barret, S. Bhandari, M.F. Mahon, K.C. Molloy, J. Organometal.
Chem. 587 (1999) 101.
[51] J.-A. van der Berg, K.R. Seddon, Cryst. Growth Des. 3 (2003) 643.
[52] G.M. Sheldrick, SHELX 97-2 Users Manual, University of Go¨ttingen,
Germany, 1977.
´
[48] J.S. Casas, E.E. Castellano, J. Ellena, M.S. Garcıa-Tasende, A.
´
Sanchez, J. Sordo, A. Touceda-Varela, Inorg. Chem. Commun. 7
[53] M.C. Burla, M. Camalli, B. Carrozzini, G.L. Cascarano, C. Giaco-
vazzo, G. Polidori, R. Spagna, J. Appl. Cryst. 36 (2003) 1103.
[54] P.W. Betteridge, J.R. Carruthers, R.I. Cooper, C.K. Prout, D.J.
Watkinm, J. Appl. Cryst. 36 (2003) 1487.
(2004) 1109.
[49] S.S. Batsanov, Inorg. Mater. 37 (2001) 871.
[50] C.J. Janiak, Chem. Soc., Dalton Trans. (2000) 3885.