Poly(germaniumpolycarbodiimides)

Article abstract of DOI:10.1016/j.ica.2007.05.001

Poly(metalpolycarbodiimides) were obtained from cyanamide or dilithium cyanamide and di-, tri- or tetra-chlorogermanes by dehydrochlorination, transmetallation or exchange GeCl/GeN reactions. The preparation was extended to mesityldichlorostibane. Metal polyhalides develop a high tendency to generate poly(metalcarbodiimide) cryptands in spite of the linear molecular shape of the carbodiimide links. In these oligomeric structures, the reactivity of the metal nitrogen bond towards protic reagents is preserved and allows the confirmation of their structure by chemical investigations.

Full text of DOI:10.1016/j.ica.2007.05.001

Inorganica Chimica Acta 360 (2007) 4031–4036
www.elsevier.com/locate/ica
Note
Poly(germaniumpolycarbodiimides)
a,
b
b
a
a
b
*
`
`
M. Dahrouch , M. Riviere-Baudet , N. Katir , J. Alvarez , E. Diaz , P. Riviere ,
b
c
c
A. Castel , I. Chavez , J.M. Manriquez
a
Departamento de Quı´mica Orga´nica, Facultad de Ciencias Quı´micas, Universidad de Concepcio´n, Casilla, 160-C Concepcio´n, Chile
Laboratoire d’He´te´rochimie Fondamentale et Applique´e, UMR 5069, Universite´ Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse cedex 9, France
b
c
Facultad de Quı´mica, Pontificia Universidad Cato´lica de Chile, casilla 306, correo 22, Santiago de Chile, Chile
Received 17 January 2007; received in revised form 17 April 2007; accepted 1 May 2007
Available online 8 May 2007
Abstract
Poly(metalpolycarbodiimides) were obtained from cyanamide or dilithium cyanamide and di-, tri- or tetra-chlorogermanes by dehy-
drochlorination, transmetallation or exchange GeCl/GeN reactions. The preparation was extended to mesityldichlorostibane. Metal
polyhalides develop a high tendency to generate poly(metalcarbodiimide) cryptands in spite of the linear molecular shape of the carbo-
diimide links. In these oligomeric structures, the reactivity of the metal nitrogen bond towards protic reagents is preserved and allows the
confirmation of their structure by chemical investigations.
Ó 2007 Elsevier B.V. All rights reserved.
Keywords: Germylpolycarbodiimides; Mesitylstibylcarbodiimide; Poly(metalpolycarbodiimide); Methoxygermane; Spirogermanes; Metalcarbodiimide
cryptands
1. Introduction
These reactions (Eqs. (1)–(3)) were extended to other
metal halides and pseudo halides (Eq. (4)) [7].
Following the extensive use of calcium carbodiimide
during the years 1925–1962 [1], the metalcyanamide chem-
istry was developed, including alkaline metal, alkaline
earth metal, transition metals [2,3], rare earth metals, [1]
and main group 14 elements [4] and Boron [5].
In the particular case of group 14 elements, the metallated
carbodiimides were prepared from metathesis reactions [6]:
(i) between a metal halide and a metallated carbodiimide
(Eqs. (1) and (2)) or (ii) between the same metal halide and
cyanamide in the presence of a basic amine (Eq. (3))
2Me3Sn-NCNꢁR0 þ R2TiCl2
! 2Me3SnCl þ R2TiðNCNR0Þ
ð4Þ
2
It was shown that the dimetallated carbodiimide form
was more stable than the cyanamide form [5,8,9] The car-
bodimide form was largely investigated by IR [10,11], the-
oretical studies [12–14] and the activation barrier for the
racemization of optically active carbodiimide was evalu-
ated [15,16]. Other metallated carbodiimides were obtained
from the insertion of cyanamide or dialkylcarbodiimide
into metal nitrogen or metal carbon bonds [7,17–25]. These
last reactions often give nitrogenated heterocycles highly
delocalized [25] (Eq. (5))
2R3SiCl þ Ag2NCN ! 2AgCN þ R3Si-NCN-SiR3
RCl2Si-SiCl2R þ Me3Si-NCN-SiMe3
! 2Me3SiCl þ 1=n½-Me2Si-SiMe2-NCN-ꢀn
2R3SiCl þ H2NCN þ 2C5H5N ! 2C5H5N; HCl
þ R3Si-NCN-SiR3
ð1Þ
ð2Þ
ð3Þ
iPr
N
iPrN=C=NiPr
S
N
Cp2M
C
ð5Þ
Cp2M
N
S
*
Corresponding author. Tel.: +33 5 61 55 83 48; fax: +33 5 61 55 82 04.
N
E-mail addresses: mdahrouch@udec.cl (M. Dahrouch), riviere@
M= Yb, Er, Dy, Y
iPr
`
chimie.ups-tlse.fr (M. Riviere-Baudet).
0020-1693/$ - see front matter Ó 2007 Elsevier B.V. All rights reserved.
doi:10.1016/j.ica.2007.05.001

4032
M. Dahrouch et al. / Inorganica Chimica Acta 360 (2007) 4031–4036
Over the last decade, these studies of carbodiimide
tered after 3 more hours at room temperature. The
solution analyzed by GC/mass showed compound 1
(M+Å = 512) with only traces of Et2GeCl2(M+Å = 202).
The concentration of the solution under 30 mmHg led
to a viscous liquid identified to almost pure compound
1. Yield 60%.
derivatives have played a very important role in a wide
array of chemical application, including prebiotic chemis-
try from interstellar cyanamide [26–29], pure organic
chemistry as the relevant transformation of carbon diox-
ide into symmetrical arylcarbodiimide [30], heterocyclisa-
tion [31,32], combinational chemistry [33] and recently
materials presenting a high intramolecular electron trans-
fer or magnetic properties [5,6,34], cyclooligomers [5],
polymers and carbodiimides latex [35–41]. In this con-
text, we synthesized and studied various germylsubsti-
tuted carbodiimides [8,9,42–45]. In the case of cyclic
oligomers obtained from the reaction of dimesityldichlor-
ogermane and the dilithium carbodiimide [42], it was
found that the trimer (Mes2GeNCN)3 was always the
main product formed. Changing the reaction conditions,
it has been possible to isolate the corresponding tetramer
and other higher oligomers (Mes2GeNCN)n with n up to
20–30.
2.1.2. Using transmetallation reaction
Et2GeCl2 (0.36 g, 1.78 mmol) was added under stirring
to a suspension of LiNCNLi (1.78 mmol) prepared from
H2NCN (0.075 g, 1.78 mmol) and nBuLi (1.6 M in hexane,
2.22 mL, 3.56 mmol) in 4 mL of THF. After 2 h at room
temperature, the THF was replaced by 8 mL of pentane
and LiCl was filtered. Concentration of the solution under
30 mmHg gave a viscous liquid which was identified to
almost pure (but not distillable without partial decomposi-
tion) compound 1. Yield 65%.
b.p.: 163 °C/30 mmHg 1H NMR (CDCl3, ppm): d 1.03–
1.10 (m, Et); 13C NMR (CDCl3, ppm): d 7.22, 7.33 (CHEtÞ;
3
The aim of this work was on the one hand, to check this
tendency of germanium halide and other metal halides to
generate metal carbodiimide cryptands in the case of an
increase of the number of carbodiimide functions around
the metal and on the other hand to study the reactivity
of the germanium nitrogen bond in the poly(germanium-
polycarbodiimide) towards protic reagents.
11.62, 12.21 (CHE2 tÞ; 136.41 (NCN). IR (KBr) masNCN:
2060 cmꢁ1. Mass (Ei/CH4): m/z 512 (M+Å, 6%), 483
(M+Å ꢁ Et, 100%), 454 (M+Å ꢁ 2Et, 11%), 425(M+Å ꢁ 3Et,
6%).
2.2. Preparation of [(MesGe)2(NCN)3]3 (2)
2.2.1. Through dehydrochlorination reaction
2. Experimental
The triethylamine (0.72 g, 7.13 mmol) was added at
room temperature under stirring to a solution of mesityltri-
chlorogermane MesGeCl3 [47] (0.71 g, 2.38 mmol) and
H2NCN (0.15 g, 3.57 mmol) in 5 mL of THF. After 3 h
at room temperature, THF was replaced with benzene
(6 mL) and Et3N, HCl was filtered. Concentration of the
remaining solution under vacuum led to a white powder
which was washed with 2 mL of pentane to eliminate pos-
sible traces of remaining MesGeCl3. Then compound 2 was
dried under vacuum leading to 0.28 g of pure compound.
Yield 75%.
All reactions were carried out under nitrogen and in
dry solvents using standard Schlenk tubes techniques.
1H NMR spectra were recorded on Bruker AC80
(80.13 MHz) and Brucker AC250 (1H(d ppm/TMS)
instruments); 13C NMR spectra were recorded on Bruker
AC200 (50.32 MHz) and ARX 400 (100.62 MHz), (d
ppm/TMS) instruments; Gas Chromatography (GC)
was undertaken on a Hewlett-Packard HP 6890 instru-
ment; mass and gas chromatography (GC/mass) and
mass spectra were recorded with a Hewlett-Packard
HP5989 in electron impact mode (Ei, 70 Ev) or a Ner-
mag R10-10 spectrometer operating in Ei mode or by
chemical desorption (DCi/CH4 or NH3), or by FAB(N-
POE); IR spectra on a Perkin Elmer 1600FT IR spec-
trometer. Elemental analyses were performed by the
‘‘Service Central de Microanalyse’’ of ‘‘Ecole Nationale
1
m.p.: 147–149 °C. H NMR (CDCl3, ppm): d 2.22 (s,
3H, p-CH3); 2.30 (s, 6H, o-CH3); 6.76 (s, 2H, C6H2).
1H NMR (CDCl3, ppm) d : 21.20 (p-CH3); 23.10
(o-CH3); Mes: 134.67 (C1); 143.80 (C2), 129.67 (C3),
142.13 (C4). IR (CDCl3) masNCN: 2138 cmꢁ1. Mass
(DCi/CH4): m/z 1511 (MH+). Anal. Calc. for
C63H66Ge6N18: C, 50.08; H, 4.40; N, 16.79. Found: C,
51.17; H, 4.73; N, 16.37%.
´
Superieure de Chimie de Toulouse’’. For crystallized
compounds, melting points were measured on a Leitz
microscope.
2.2.2. Using transmetallation reaction
MesGeCl3 (0.70 g, 2.38 mmol) was added under stirring
and at room temperature to a solution of LiNCNLi
(3.57 mmol) prepared from H2NCN (0.15 g, 3.57 mmol)
and nBuLi (1.6 M in hexane, 4.46 mL, 7.14 mmol) in
8 mL of THF. After 3 h, THF was replaced by 8 mL of
benzene and LiCl was eliminated by filtration. Concentra-
tion of the remaining solution under vacuum led to a white
powder which was washed with 3 mL of pentane to elimi-
nate possible traces of remaining MesGeCl3. Then com-
2.1. Preparation of (Et2GeNCN)3 (1)
2.1.1. Through dehydrochlorination reaction
Diethyldichlorogermane
Et2GeCl2
[46]
(0.49 g,
2.42 mmol) was added under stirring to a solution of
cyanamide (0.10 g, 2.40 mmol) and Et3N (0.72 g,
7.13 mmol) in 7 mL of THF. The reaction occurs imme-
diately with precipitation of Et3N, HCl which was fil-

M. Dahrouch et al. / Inorganica Chimica Acta 360 (2007) 4031–4036
4033
pound 2 was dried under vacuum leading to 0.31 g of pure
2.5. Chemical characterization of 4
compound. Yield: 84%.
2.5.1. Reaction with methanol
2.3. Preparation of (MesSbNCN)5 (3)
In an NMR tube, were mixed 4 (0.012 g, 0.078 mmol)
and a solution of methanol (0.010 g, 0.310 mmol) in
0.5 mL of CDCl3. The insoluble 4 reacted, leading first to
a homogeneous solution. Then after 3 h at room tempera-
ture, a new white solid precipitated. The analysis of the
liquid phase using GC/internal reference and by compari-
son with an authentic sample of Ge(OMe)4 5 [51] showed
an almost quantitative formation of 5 also characterized
by 1H NMR (CDCl3, d ppm: 3.66 OCH3), 13C NMR
(CDCl3, d ppm: 53.44 OCH3), and mass analysis (Ei):
A solution of MesSbCl2 [48–50] (0.67 g, 2.14 mmol) in
6 mL of THF was added to a suspension of LiNCNLi
(2.14 mmol) prepared from H2NCN (0.09 g, 2.14 mmol)
and nBuLi (1.6 M in hexane, 2.68 mL, 4.28 mmol) in
4 mL of THF. After 4 h under stirring at room tempera-
ture, the THF was replaced by 5 mL of C6H6 and LiCl
was filtered. Concentration of the solution under vacuum
led to 0.41 g of 3 as a white powder which was then recrys-
tallized in CH2Cl2/pentane. Yield: 68%.
168
(MH+ ꢁ OMe);
137
(MH+ ꢁ 2MeO);
105
1
m.p.: 155–157°C. H NMR (CDCl3, ppm): d 2.21 (s,
(MH+ ꢁ 3MeO); (DCi/NH3): 199 (MH+); 216 (MNH þ);
4
15H, p-CH3); 2.32 (s, 30H, o-CH3); 6.78 (s, 10H, C6H2).
13C NMR (CDCl3, ppm) d: 21.04 (p-CH3); 23.96 (o-
CH3); Mes: 140.25 (C1); 143.70 (C2), 129.22 (C3), 138.74
233 (MN2H7þ). The white precipitate was then identified
as cyanamide (m.p.: 46 °C).
(C4), 138.36 (NCN). IR (CDCl3) mas(NCN): 2055 cmꢁ1
.
2.5.2. Reaction with 3,5-di-t-butylcatechol
Mass (DCi/CH4): m/z 1405 (MH+). Anal. Calc. for
C50H55Sb5N10: C, 42.75; H, 3.95; N, 9.97. Found: C,
41.93; H, 4.08; N, 10.18%.
To 4 (0.16 g) in 2 mL of THF was added a solution
of 3,5-di-tert-butylcathecol (0.46 g, 2.1 mmol) in 5 mL of
THF. After 4 h at room temperature and replacement
of THF by 4 mL of benzene, the elimination of the insolu-
ble cyanamide by centrifugation led to a solution which,
when evaporated under vacuum, gave 0.51 g (yield 94 %)
of the spirogermane 6 identified by 1H NMR [52]
(CDCl3/DMSO-d6, 50/50): 1.23 (s, 18 H, tBu); 1.60 (s,
18H, tBu); 6.68 and 6.85 (m, 4H, C6H2) and mass spectros-
copy (Ei, m/z: M+Å: 514).
2.4. Preparation of [Ge(NCN)2]n (4)
2.4.1. Through dehydrochlorination reaction
To a solution of cyanamide (0.08 g, 1.86 mmol) and
Et3N (0.37 g, 3.72 mmol) in 6 mL of THF, GeCl4
(0.20 g, 0.93 mmol) was added slowly under stirring.
After 2 h at room temperature, THF was replaced with
7 mL of CHCl3 to eliminate the soluble Et3N,HCl. Com-
pound 4 was then isolated by filtration. 0.11 g. Yield:
78%.
3. Results and discussion
To increase the number of germanium carbodiimide
units around the metal, we decided to start from polyhalo-
genated germanium compounds: Et2GeCl2, MesGeCl3 and
GeCl4, using their reactions: (i) with the dilithium carbodii-
mide, (ii)with cyanamide in the presence of a basic amine
or (iii) the exchange reaction GeCl/GeN (Schemes 1–3).
We observed [42] that reaction between dimesityldi-
chlorogermane with dilithium carbodimide gave cyclo-
poly(dimesithylgermyl carbodiimide) (Mes2GeNCN)n
with n = 3, 4. It was not possible to obtain polymers with
higher molecular weight supposedly because the mesityl
substituents were quite bulky. Therefore, polygermylcarbo-
diimide with higher degree of polymerization could be
expected using smaller substituents like ethyl groups. The
reaction was performed from diethyldichlorogermane
2.4.2. Through transmetallation reaction
To a suspension of LiNCNLi (2.86 mmol) prepared
from H2NCN (0.12 g, 2.86 mmol) and nBuLi (1.6 M,
3.57 mL, 5.72 mmol) in 5 mL of THF, GeCl4 (0.30 g,
1.39 mmol) was added at room temperature under strir-
ring. After 3 h, the solution was warmed and LiCl elimi-
nated by filtration. A white powder (0.15 g) of 4
precipitated on cooling and was isolated by filtration.
Yield: 71%.
2.4.3. Through GeCl/Ge-N exchange reaction
GeCl4 (0.31 g, 1.43 mmol) was added to a solution of
bis(triethylgermyl)carbodiimide [43] (1.03 g, 2.86 mmol) in
3 mL of THF. The exchange reaction was followed by
GC from the formation of Et3 GeCl and until the complete
transformation of (Et3Ge)2NCN. Compound 4 was then
isolated by filtration and washed with 3 mL of ether and
dried under vacuum (0.16 g). Yield: 73%.
THF
Et2GeCl2 + LiNCNLi
- 2 LiCl
i)
m.p.: >370°C; IR (nujol) mas(NCN): 2165 cmꢁ1. Mass
(FAB, Nitro-Phenyl-Octyl-Ether: NPOE): m/z 306 (M+Å,
[Ge(NCN)2]2), 458 (M+Å, [Ge(NCN)2]3). Anal. Calc. for
(C2GeN4)n: C, 15.74; N, 36.71. Found: C, 16.04; N,
36.98%.
(Et2GeNCN)n
+2
Et3N
Et2GeCl2 + H2NCN
ii)
(n=3)
1
-2 Et3N,HCl
Scheme 1.

4034
M. Dahrouch et al. / Inorganica Chimica Acta 360 (2007) 4031–4036
THF
NCN
RGe
GeR
GeR
2 MesGeCl3 + Li2NCN
i)
-6LiCl
N
N
N
N
C
C
C
C
N
N
N
[(MesGe)2(NCN)3]3
N
+ 6 Et3N
Ge
R
ii)
2
NCN
RGe
2 MesGeCl3 + 3 H2NCN
- 6 Et3N, HCl
N
N
N
C
Scheme 2.
C
C
N
N
N
Ge
R
THF
A
GeCl4 + 2 Li2NCN
GeCl4 + 2 H2NCN
i)
- 4 LiCl
ii)
4 Et3N
1
n
[(Ge(NCN)2]n
- 4 Et3N,HCl
4
- 4 Et3GeCl
Ge
iii)
Cl4 + 2 Et3GeNCNGeEt3
Scheme 3.
using both (i) and (ii) methods (Scheme 1). However, the
only product identified was the cyclic trimer (n = 3). Mass
analysis showed the molecular ion (Ei) M+Å = 512. The
shape of this molecular ion being characteristic of a Ge3
molecule.
Fig. 1. Proposed formula and geometry optimisation for A (R = Me)
Hyperchem PM3 level.
It seems that, even with smaller substituents, the ten-
dency of the reaction is still the cyclooligomerization.
To increase the number of NCN bond units around ger-
manium, we used MesGeCl3 in reactions (i) and (ii).
Both reactions (i) and (ii) led to similar yields (75–80%)
Germanium tetrachloride, reacted by the three reactions
pathways (i), (ii), (iii), led to the same white solid (Scheme
3).
1
of the same white solid compound. The H and 13C NMR
analyses showed only one kind of mesityl signals leading to
the conclusion that the reaction gives only one compound
which is present in IR as the NCN absorption at
2138 cmꢁ1. The mass spectrometry (DCi/CH4) analysis
allows the characterization of the MH+ signal at 1511
whose isotopic distribution is typical of a Ge6 compound
confirming the structure [(MesGe)2(NCN)3]3.
This crude formula could be attributed mostly to the
more stable molecular structure A (Fig. 1) from semi
empirical calculations performed for [(MeGe)2(NCN)3]3
at the Hyperchem PM3 level.
However, as reactions of organogermaniumdi- and tri-
halides with metalated carbodiimide or cyanamide in the
presence of a base (Schemes 1–3) lead mainly to cycloolig-
omers, we intended to know if this fact can be extended to
other metal dihalides and performed reaction (i) with the
mesityldichlorostibane (Eq. (6)). The cyclopentamer was
characterized in mass spectrometry (DCi/CH4) by
MH+ = 1405 with the isotopic distribution of a Sb5
compound.
This compound appears physically similar to the com-
pound obtained in the metathesis reaction of germanium
tetrachloride with bis(trimethylsilyl)carbodiimide (Eq. (7))
[5]
nGeCl4 þ 2nMe3SiNCNSiMe3 ! 4nMe3SiCl þ ½GeðNCNÞ2ꢀn
4
ð7Þ
This white solid is insoluble in the classical solvents,
1
which does not allow H and 13C NMR. Infrared analysis
shows a characteristic absorption at 2165 cmꢁ1 (m NCN).
Mass analysis by FAB (NPOE) technique allows the obser-
vation of polymer units (n = 2, M+Å = 306) and (n = 3,
M+Å = 458) probably formed from the fragmentation of a
polydimensional polymer.
Chemical characterizations using protic cleavages
(methanol, 3,5-di-tert-butylcatechol) (Scheme 4) of the
Ge–N bonds present in the polymer (Scheme 3) confirmed
the presence of four germanium nitrogen bonds around the
metal.
To explain the observed fragmentation of the
[Ge(NCN)2]n polymer the most probable hypothesis would
be the coexistence in the polymer of polygermacyclic struc-
ture of B type (Scheme 5) and of polygermaspiranic struc-
ture of C type (Scheme 6).
1
THF
MesSbCl2 þ Li2NCN ꢁꢁ2!LiCl ðMesSbNCNÞ5
ð6Þ
5
3
With a metal tetrahalide, the formation of a polydimen-
sional polymer seems to occur.

M. Dahrouch et al. / Inorganica Chimica Acta 360 (2007) 4031–4036
4035
MeOH
+ n Ge(OMe)4
2n H2NCN
5
[Ge(NCN)2]
n
tBu
tBu
O
O
O
2n H2NCN
Ge
+
tBu
O
tBu
HO
HO
6
tBu
tBu
Scheme 4.
[3] H. Sen So, J.S. Figueroa, C.C. Cummins, J. Am. Chem. Soc. 126
(2004) 11370.
[4] J.R. Babcock, C. Incarvito, A.L. Rheingold, J.C. Fettinger, L.R. Sita,
Organometallics 18 (1999) 5729.
[5] R. Riedel, E. Kroke, A. Greiner, A.O. Gabriel, L. Ruwisch, J.
Nicolich, Chem. Mater. 10 (1998) 2964.
[6] R. Srinivasan, M. Stro¨bele, H.J. Meyer, Inorg. Chem. 42 (2003) 3406.
[7] G. Veneziani, S. Shimada, M. Tanaka, Organometallics 17 (1998)
2926.
NCN
NCN
NCN
NCN
Ge
Ge
Ge
a
Ge
Ge
Ge
Ge
NCN
a
NCN
NCN
NCN
Ge
Ge
NCN
a
NCN
NCN
NCN
NCN
NCN
Ge
a
B
`
`
[8] M. Riviere-Baudet, M. Dahrouch, P. Riviere, K. Hussein, J.C.
a fragmentation leads to M+. = 306
Barthelat, J. Organomet. Chem. 612 (2000) 69.
`
[9] S. Boughdiri, K. Hussein, B. Tangour, M. Dahrouch, M. Riviere-
Scheme 5.
Baudet, J.C. Barthelat, J. Organomet. Chem. 689 (2004) 3279.
[10] H. Maekawa, K. Ohta, K. Tominaga, J. Phys. Chem. A 108 (2004)
9484.
Ge
Ge
[11] H. Maekawa, K. Ohta, K. Tominaga, J. Mol. Struct. 735–736 (2005)
135.
Ge
Ge
b
b
Ge
NCN
NCN
NCN
NCN
NCN
NCN
[12] A. Kuhn, M. Vosswinkel, C. Wentrup, J. Org. Chem. 67 (2002) 9023.
[13] M. Lewis, Z. Wu, R. Glaser, J. Phys. Chem. A 104 (2000) 11355.
[14] R. Glaser, M. Lewis, Z. Wu, J. Phys. Chem. A 106 (2002) 7950.
[15] P. Molina, M. Alajarin, P. Sanchez-Andrada, J. Org. Chem. 61 (1996)
4289.
Ge
Ge
b
NCN
NCN
b
C
[16] K. Schlo¨gl, H. Mechtler, Angew. Chem. Int. Ed. 606 (5) (1966) 596.
[17] A.P. Kenney, G.P.A. Yap, D.S. Richeson, S.T. Barry, Inorg. Chem.
44 (2005) 2926.
b fragmentation leads to M+. = 458
Scheme 6.
[18] C.N. Rowley, G.A. Dilabio, S.T. Barry, Inorg. Chem. 44 (2005) 1983.
[19] J. Zhang, X. Zhou, R. Cai, L. Weng, Inorg. Chem. 44 (2005) 716.
[20] J. Zhang, R. Cai, L. Weng, X. Zhou, Organometallics 23 (2004) 3303.
[21] J. Zhang, R. Ruan, Z. Shao, R. Cai, L. Weng, X. Zhou, Organo-
metallics 21 (2002) 1420.
4. Conclusion
Although the carbodiimide function presents a central
linear molecular shape, metal polyhalides develop high ten-
dency to generate poly (metalcarbodiimide) cryptands. In
these oligomeric structures, the reactivity of the metal
nitrogen bond towards protic reagents is preserved and
allows the confirmation of their structure by chemical
investigations.
[22] J. Vicente, J.A. Abad, M.J. Lopez-Saez, Organometallics 25 (2006)
1851.
[23] M.D. Li, C.C. Chang, Y. Wang, G.H. Lee, Organometallics 15 (1996)
2571.
[24] L. Ma, J. Zhang, R. Cai, Z. Chen, L. Weng, X. Zhou, J. Organomet.
Chem. 690 (2005) 4926.
[25] J. Zhang, R. Cai, L. Weng, X. Zhou, J. Organometal. Chem. 672
(2003) 94.
[26] F. Duvernay, T. Chiavassa, F. Borget, J.P. Aycard, J. Am. Chem.
Soc. 126 (2004) 7772.
[27] M. Lewis, R. Glaser, J. Am. Chem. Soc. 120 (1998) 8541.
[28] F. Tordini, A. Bencini, M. Bruschi, L. de Gioia, G. Zampella, P.
Fantucci, J. Phys. Chem. A 107 (2003) 1188.
[29] F. Duvernay, T. Chiavassa, F. Borget, J.P. Aycard, J. Phys. Chem. A
109 (2005) 603.
[30] U.J. Kilgore, F. Basuli, J.C. Huffman, D.J. Mindiola, Inorg. Chem.
45 (2006) 487.
Acknowledgements
The authors thank the ECOS CONICYT program
C04E05 and FONDECYT 1040455 y FONDECYT
7050190, for partial financial support.
References
[31] W.X. Zhang, M. Nishiura, Z. Hou, J. Am. Chem. Soc. 127 (2005)
16788.
[1] X. Liu, M. Krott, P. Muller, C. Hu, H. Lueken, R. Dronkowski,
¨
[32] A. Volonterio, C. Ramirez de Arellano, M. Zanda, J. Org. Chem. 70
(2005) 2161.
Inorg. Chem. 44 (2005) 3001.
[2] D.A. Kissounko, J.C. Fettinger, L.R. Sita, Inorg. Chim. Acta 345
(2003) 121.
[33] M. Zhang, P. Vedantham, D.L. Flynn, P.R. Hanson, J. Org. Chem.
69 (2004) 8340.

4036
M. Dahrouch et al. / Inorganica Chimica Acta 360 (2007) 4031–4036
`
[34] A. Tarraga, F. Oton, A. Espinosa, M. Desamparados-Velasco, P.
Molina, D.J. Evans, Chem. Commun. (2004) 458.
[44] M. Riviere-Baudet, M. Dahrouch, H. Gornitzka, J. Organomet.
Chem. 595 (2000) 153.
`
[35] G. Tian, Y. Lu, B.M. Novak, J. Am. Chem. Soc. 126 (2004) 4082.
[36] A. Amore, R. Van Heerbeek, N. Zeep, J. Van Esch, J.N.H. Reek, H.
Hiemstra, J.H. Van Maarseveen, J. Org. Chem. 71 (2006) 1851.
[37] H.H. Pham, M.A. Winnik, Macromolecules 39 (2006) 1425.
[38] K. Shibayama, S.W. Seidel, B.M. Novak, Macromolecules 30 (1997)
3159.
[45] M. Riviere-Baudet, M. Dahrouch, H. Gornitzka, Phosphorus, Sulfur
Silicon 159 (2000) 23.
[46] M. Lesbre, P. Mazerolles, J. Satge, The Organic Compounds of
´
Germanium, Wiley, London, 1971.
`
`
[47] P. Riviere, M. Riviere-Baudet, in: R.B. King, J.J. Eisch (Eds.), Org.
Met. Synth, vol. 4, Elsevier, NY, 1988, p. 542.
[39] H.H. Pham, M.A. Winnik, Macromolecules 32 (1999) 7692.
[40] C. Balan, K.W. Volger, E. Kroke, R. Riedel, Macromolecules 33
(2000) 3404.
[41] S. Nahar- Borchert, E. Kroke, R. Riedel, B. Boury, R.J.P. Corriu, J.
Organomet. Chem. 686 (2003) 127.
[48] M. Ates, H.J. Breunig, A. Soltani-Neshan, M. Tegele, Z. Natur-
forsch. 41b (1986) 321.
[49] J.D. Smith, Arsenic and Bismuth in Comprehensive Inorganic
Chemistry, vol. 2, Wiley, NY, 1998, p. 447 (Chapter 21).
`
`
[50] Z. Ben Maarouf, P. Riviere, M. Riviere-Baudet, A. Castel, A.
Khaalayoun, M. Ahbala, Phosphorus, Sulfur Silicon 128 (1997) 19.
[51] O.H. Johnson, H.E. Fritz, J. Am. Chem. Soc. 75 (1953) 718.
`
´
[42] M. Dahrouch, M. Riviere-Baudet, J. Satge, M. Mauzac, C.J. Cardin,
J.H. Thorpe, Organometallics 17 (1998) 623.
`
`
´
[43] M. Dahrouch, M. Riviere-Baudet, H. Gornitzka, G. Bertrand, J.
[52] P. Riviere, A. Castel, J. Satge, D. Guyot, J. Organomet. Chem. 315
Organomet. Chem. 562 (1998) 191.
(1986) 157.