Unusual In2N4 cores in complexes containing triazole-based chalcogen-phosphoranyl ligands

Article abstract of DOI:10.1021/ic051567p

The 4,5-bis(diphenylphosphoranyl)-1,2,3-triazole [4,5-(P(E)Ph ₂)₂tz] derivatives of indium {κ³-N, N′,E-[4,5-(P(E)Ph₂)₂-(μ-tz)]InMe ₂}₂ (E = O(2), S(3), Se(4)) were prepared in good yield. In addition, compound 5 (E = O, E′ = Se) was obtained from 4 through the replacement of a selenium atom in the P-Se(In) moiety by an oxygen atom, giving the mixed-chalcogen complex. The crystal structures of 2 and 5 exhibit a central C₄In₂N₆O₂P₄ core with an almost planar arrangement (mean deviation = 0.019 and 0.042 A for 2 and 0.100 A for 5), while the C₄In₂N₆S ₂P₄ core in 3 is nonplanar (mean deviation = 0.223 A).

Full text of DOI:10.1021/ic051567p

Inorg. Chem. 2006, 45, 5167−5171
Unusual In2N4 Cores in Complexes Containing Triazole-Based
Chalcogen Phosphoranyl Ligands
−
Mo´nica Moya-Cabrera,*,† Vojtech Jancik,† Rafael A. Castro,† Regine Herbst-Irmer,‡ and
Herbert W. Roesky‡
Institute of Chemistry, UNAM, Circuito Exterior, Ciudad UniVersitaria, 04510, Me´xico, and
Institute of Inorganic Chemistry, Georg-August UniVersita¨t, Tammannstrasse 4,
37077, Go¨ttingen, Germany
Received September 13, 2005
The 4,5-bis(diphenylphosphoranyl)-1,2,3-triazole [4,5-(P(E)Ph2)2tz] derivatives of indium {κ3-N,N
′
,E-[4,5-(P(E)Ph2)2-
O, E′ ) Se)
Se(In) moiety by an oxygen atom,
giving the mixed-chalcogen complex. The crystal structures of 2 and 5 exhibit a central C4In2N6O2P4 core with an
almost planar arrangement (mean deviation 0.019 and 0.042 Å for 2 and 0.100 Å for 5), while the C4In2N6S2P4
core in 3 is nonplanar (mean deviation 0.223 Å).
(
µ−tz)]InMe2
}
(E
)
O(2), S(3), Se(4)) were prepared in good yield. In addition, compound 5 (E
)
2
was obtained from 4 through the replacement of a selenium atom in the P
−
)
)
Introduction
is attached to one O and one N atom, forming a CoOPCN
five-membered ring. The latter coordination pattern was also
observed in palladium complexes containing the [4,5-(P(S)-
Ph2)2tz] ligand.3 Motivated by an interest in the effects of
these ligands on the coordination geometry of p-block
elements, namely group 13 elements, we began a systematic
study for indium compounds. Moreover, taking into account
that group 13 elements form M2N4 six-membered rings with
azoles,4 multidentate ligands containing PdE groups such
as [4,5-(P(E)Ph2)2tz] (E ) O(1a), S(1b), Se(1c)) can offer
additional coordination sites which can provide unusual
structural features and chemical reactivities, as well as
enhance the stability of the complexes. Herein, we report
the synthesis and structural characterization of {κ3-N,N′,E-
[4,5-(P(E)Ph2)2(µ-tz)]InMe2}2 derivatives. Compounds 2, 3,
and 5 all exhibit the same type of dimeric-like arrangement
with a planar In2N4 core.
During the past three decades, P-Y-P-unit-containing
species (Y ) N, C, alkyl, heterocycle) have received
considerable attention as ligands in the coordination chem-
istry of p-block elements.1 The Lewis base character of P(III)
and its facile oxidation with elemental chalcogens or azides
to P(V) modifies its coordination properties. In addition, the
large variety of available Y linkage groups leads to further
coordination diversity for these types of ligands.
Recently, Trofimenko reported the preparation of the 4,5-
bis(diphenylphosphoranyl)-1,2,3-triazole [4,5-(P(O)Ph2)2tz]
ligand and its complexes with uranium and cobalt, both of
which display an interesting coordination behavior.2 The
uranium atom coordinates exclusively to the oxygen atoms,
forming a seven-membered ring (UOPCCPO), while the Co
* To whom correspondence should be addressed. Fax: +52 55 56 16
22 17. Tel: +52 55 56 22 44 04. E-mail: monica.moya@correo.unam.mx.
† UNAM.
(3) Rheingold, A. L.; Liable-Sands, L. M.; Trofimenko, S. Inorg. Chim.
Acta. 2002, 303, 38-43.
‡ Georg-August Universita¨t.
(1) (a) Silvestru, C. Drake, J. E. Coord. Chem. ReV. 2001, 223, 117-
216. (b) Hill, M. S.; Hitchcock, P. B.; Karagouni, S. M. A. J.
Organomet. Chem. 2004, 689, 722-730. (c) Power M. B.; Ziller, J.
W.; Barron, A. R. Organometallics 1993, 12, 4908-4916. (d) Aparna,
K.; McDonald, R.; Ferguson, M.; Cavell, R. G. Organometallics 1999,
18, 4241-4243. (e) Ong, C. M.; McKarns, P.; Stephan, D. W.
Organometallics 1999, 18, 4197-4204.
(2) The coordination modes of {[(4,5-(P(O)Ph2)2tz]Rh(cod)}, {[(4,5-(P(O)-
Ph2)2tz]3Mg}[HNEt3], and {[(4,5-(P(O)Ph2)2tz]3La} have been identi-
fied but not fully structurally characterized. See Rheingold, A. L.;
Liable-Sands, L. M.; Trofimenko, S. Angew. Chem., Int. Ed. 2000,
39, 3321-3324.
(4) (a) Rendle, D. F.; Storr, A.; Trotter, J. Can. J. Chem. 1975, 53, 2944-
2954. (b) Rendle, D. F.; Storr, A.; Trotter, J. Can. J. Chem. 1975, 53,
2930-2943. (c) Rendle, D. F.; Storr, A.; Trotter, J. J. Chem. Soc.,
Dalton Trans. 1973, 2252-2255. (d) Ward, D. M.; Mann, K. L. V.;
Jeffery, J. C.; McCleverty, J. A. Acta Crystallogr. 1998, C54, 601-
603. (e) Hausen, H. D.; Locke, K.; Weidlein, J. J. Organomet. Chem.
1992, 429, C27-C32. (f) Zheng, W.; Mo¨sch-Zanetti, N. C.; Roesky,
H. W.; Hewitt, M.; Cimpoesu, F.; Schneider, T. R.; Stasch, A.; Prust,
J. Angew. Chem., Int. Ed. 2000, 39, 3099-3102. (g) Zheng, W.;
Hohmeister, H.; Mo¨sch-Zanetti, N.; Roesky, H. W.; Noltemeyer, M.;
Schmidt, H.-G. Inorg. Chem. 2001, 40, 2363-2367 and references
therein.
10.1021/ic051567p CCC: $33.50
Published on Web 06/03/2006
© 2006 American Chemical Society
Inorganic Chemistry, Vol. 45, No. 13, 2006 5167

Moya-Cabrera et al.
Scheme 1
Experimental Section
General Comments. All reactions and handling of reagents were
performed under an atmosphere of dry nitrogen or argon using
standard Schlenk techniques or a glovebox where the O2 and H2O
levels were usually kept bellow 1 ppm. All glassware was oven-
dried at 140 °C for at least 24 h, assembled hot, and cooled under
high vacuum prior to use. Toluene (Na/benzophenone ketyl),
pentane (Na/K/benzophenone ketyl), and tetrahydrofuran (K/
benzophenone ketyl) were dried and distilled prior to use. InMe3
(Strem) was used as received, and compounds 1a-c were prepared
according to literature procedures.2,3 Mass spectra were recorded
on a Finnigan Mat 8230 instrument, and IR spectra were recorded
on a Bio-Rad digilab FTS-7 spectrometer in the 4000-350 cm-1
1
range as Nujol mulls. H (500 MHz) and 31P NMR (202.5 MHz)
were recorded on a Bruker Avance 500 NMR spectrometer at -55
or 20 °C, chemical shifts were referenced to TMS (1H) and H3PO4
85% (31P). Elemental analyses were performed by Galbraith
Laboratories (Knoxville, TN). Melting points were measured in
sealed glass tubes and were not corrected.
three-circle diffractometer equipped with a SMART 6000 CCD
detector using mirror-monochromated CuKR radiation (λ ) 1.54178
Å). The data for all compounds were collected at 100 K with the
PROTEUM5 program using φ- and ω-scans and integrated with
the SAINT5 program. Semiempirical absorption correction from
the equivalents was applied (SADABS).5 The space groups were
determined with XPREP5 program, and the structures were solved
by direct methods (SHELXS-97)6 and refined with all data by full-
matrix least-squares methods on F2 using SHELXL-97.7
Preparation of {K3-N,N′,O-[4,5-(P(O)Ph2)2(µ-tz)]InMe2}2 (2).
A solution of InMe3 (0.16 g, 1 mmol) in hexanes (5 cm3) was added
at ambient temperature to a suspension of 1a (0.47 g, 1 mmol) in
toluene (10 cm3), gas evolution was observed, during which the
solid dissolved completely, and after 10 min a white precipitate
was formed. The reaction mixture was filtered, and the solid was
washed with toluene (2 × 5 cm3). The crude product was
recrystallized from warm THF (5 cm3), giving colorless crystals
(0.50 g, 81%) mp 250 °C (dec); IR ν˜(Nujol/cm-1): 2953, 1460,
Results and Discusion
Addition of 1 equiv of trimethylindium to the slurry of
the free ligand (1a-c) in toluene resulted in the immediate
elimination of methane, during which all the solid was
dissolved. After the removal of the toluene under vacuum
and washing, the remaining solid with cold hexane, {κ3-
N,N′,O-[4,5-(P(O)Ph2)2(µ-tz)]InMe2}2 (2), {κ3-N,N′,S-[4,5-
(P(S)Ph2)2(µ-tz)]InMe2}2 (3), and {κ3-N,N′,Se-[4,5-(P(Se)-
Ph2)2(µ-tz)]InMe2}2 (4) were obtained in good yields (68-
81%). In all three cases, the formation of a dinuclear In2N4
six-membered ring with coordination of In to one chalcogen
atom was observed (Scheme 1).
1
1376, 1120; H NMR (500 MHz, THF-d8, 20 °C, TMS) δ 7.98,
7.75 (m, 16H, o-Ph-H), 7.42-7.17 (m, 24H, m, p-Ph-H), -0.10
(s, 12H, InCH3); 31P NMR (202.5 MHz, THF-d8, 20 °C, H3PO4
85%) δ 32.4 (PdO), 17.7 (P-O(In)); EI-MS (70 eV): m/z 1211
(M+ - CH3, 1), 613 (M+/2 - CH3, 100). Anal. Calcd for C56H52-
In2N6P4O4 (1226.60 g‚mol-1): C 54.8; H 4.3. Found: C 54.9; H
4.4%.
Preparation of {K3-N,N′,S-[4,5-(P(S)Ph2)2(µ-tz)]InMe2}2 (3).
A similar procedure as that for 2 was used starting from 1b (0.50
g, 1.0 mmol) and a solution of InMe3 (0.16 g, 1 mmol) in hexanes
(5 cm3), giving pale yellow crystals (0.45 g, 70%) mp 305 °C (dec);
1
IR ν˜(Nujol/cm-1): 3015, 1438, 1387, 1103; H NMR (500 MHz,
Compounds 2-4 were characterized by analytical and
spectroscopic studies, and compounds 2 and 3 were further
characterized by X-ray diffraction experiments. The IR
spectra of these compounds are all devoid of N-H absorption
THF-d8, -55 °C, TMS) δ 7.58 (m, 16H, o-Ph-H), 7.40-7.15 (m,
24H, m, p-Ph-H), 0.07 (s, 12H, InCH3); 31P NMR (202.5 MHz,
THF-d8, -55 °C, H3PO4 85%) δ 36.5 (PdS), 30.2 (P-S(In)); EI-
MS (70 eV): m/z 1275 (M+ - CH3, 1), 630 (M+/2 - CH3), 100).
Anal. Calcd for C56H52In2N6P4S4 (1290.84 g‚mol-1): C 52.1; H
4.1. Found: C 51.8; H 3.9%.
Preparation of {K3-N,N′,Se-[4,5-(P(Se)Ph2)2(µ-tz)]InMe2}2 (4).
A similar procedure as that for 2 was used starting from 1c (0.59
g, 1.0 mmol) and a solution of InMe3 (0.16 g, 1 mmol) in hexanes
(5 cm3), giving a white crystalline powder (0.51 g, 68%) mp 320
°C (dec); IR ν˜(Nujol/cm-1): 2923, 1462, 1101, 1377, 687; 1H NMR
(500 MHz, THF-d8, 20 °C, H3PO4 85%): δ 8.13, 7.89 (m, 16H,
o-Ph-H), 7.51, 7.50 (m, 8H, p-Ph-H), 7.49, 7.44 (m, 16H, m-Ph-
H) 0.19 (s, 12H, InCH3). 31P NMR (121.5 MHz, THF-d8, 20 °C,
H3PO4 85%) δ 34.3 (PdSe), 11.9 (P-Se(In)); EI-MS (70 eV): m/z
837 (C21H18In2N6P3Se2, 5), 822 (C20H15In2N6P3Se2, 10), 741 (M+/
2, 3), 726 (M+/2 - CH3, 3), 646 (M+/2 - SeCH3, 100). Anal.
Calcd for C56H52In2N6P4Se4 (1478.44 g‚mol-1) C 45.5; H 3.6.
Found: C 46.7; H 3.8%.
1
in the range of 3000-3200 cm-1, and the H NMR spectra
(THF-d8) display the characteristic patterns owing to the
deprotonated ligands. The 31P NMR spectra for these
complexes at ambient temperature show two broad reso-
nances for 2 (32.4 and 17.7 ppm) and 4 (34.3 and 11.9 ppm).
On the other hand, compound 3 exhibited only one broad
resonance at 33.5 ppm, although a low-temperature 31P NMR
experiment carried out at -55 °C revealed two sharp
resonances (36.5 and 30.2 ppm), indicating the presence of
a fluxional behavior at ambient temperature. However, low-
temperature NMR experiments performed on 2 and 4 resulted
merely in the sharpening of their signals. The NMR behavior
(5) PROTEUM (v. 1.40), SAINT (v. 7.01A), SADABS (v. 2004/1), and
XPREP (v. 2005/1); Bruker Analytical X-ray Instruments, Inc.:
Madison, WI.
(6) Sheldrick, G. M. Acta Crytallogr. Sect. A 1990, 46, 467-473.
(7) Sheldrick, G. M. SHELXL-97, Program for Crystal Structure Refine-
ment, Universita¨t Go¨ttingen: Go¨ttingen, Germany, 1997.
Crystal Data Collection, Structure Solution, and Refinement
Details for Compounds 2, 3, and 5‚2THF. The diffraction data
for the compounds 2, 3, and 5‚2THF were measured on a Bruker
5168 Inorganic Chemistry, Vol. 45, No. 13, 2006

Unusual In2N4 Cores in Triazole-Based Complexes
Figure 1. Molecular structure and numbering scheme of molecule 1 of
the centrosymmetric dimer 2 (50% probability ellipsoids). All hydrogen
atoms are omitted for clarity. For the molecular structure and numbering
scheme of molecule 2, see Figure S1 in the Supporting Information.
Figure 2. Molecular structure and numbering scheme of the centrosym-
metric dimer 3 (50% probability ellipsoids). All hydrogen atoms are omitted
for clarity.
of compound 3 contrasts with that in 4 were the strong In-O
bonding seems to prevent the ligand exchange process taking
place at ambient temperature. Whereas, in the case of 4, the
larger size of the selenium atom (compared to that of the
sulfur atom in 3) seems to contribute to a higher energetic
barrier for the same type of exchange process and is therefore
slow in the NMR time scale at ambient temperature.
Electron impact (EI) spectrometry revealed peaks at m/z
1211 and 1275 corresponding to the (M+ - CH3) fragments
for 2 and 3, respectively. Compound 4 exhibits a (M+/2)
peak at m/z 741 along with higher fragments at m/z 822
(C20H15115In2N6P380Se2) and 837 (C21H18115In2N6P380Se2) which
reveal its dimeric nature.
In an attempt to grow X-ray-quality crystals of 4 from
hot THF, precipitation of red selenium was observed. Further
structural analysis of the product revealed the replacement
of the selenium atom in the P-Se(In) moiety by an oxygen
atom, leading to the formation of a mixed-chalcogen complex
(5) (Scheme 1). To gain further insight on this chalcogen
exchange process, we performed controlled hydrolysis and
oxidation experiments on 1c and 4.8 Unfortunately, none of
these reactions led to the formation of the mixed-chalcogen
species, and thus far, we have not been able to reproduce
the synthesis of 5.
Structural Description. Colorless X-ray-quality crystals
of 2, 3, and 5‚2THF were obtained by slowly cooling their
saturated THF solutions from 65 °C to ambient temperature.
Compounds 2, 3, and 5 crystallize in a triclinic space group
P1h with two independent halves of the molecule (2) (Figure
1), one-half of the molecule (3) (Figure 2), and one-half of
the molecule solvated by one THF molecule (5) (Figure 3)
in the asymmetric unit, respectively. The crystal data and
Figure 3. Molecular structure and numbering scheme of the centrosym-
metric dimer 5‚2 THF (50% probability ellipsoids). All hydrogen atoms
and the solvating THF molecules are omitted for clarity.
refinement details for all three structures are tabulated in
Table 1, and selected bond lengths and angles complexes 2,
3, and 5 are listed in Table 2.
The central C4In2N6O2P4 core in both independent mol-
ecules in 2 exhibits an almost planar arrangement with a
mean deviation of 0.019 and 0.042 Å. Whereas, for
compound 5, the mean deviation of these atoms is 0.100 Å,
and finally, the planarity disappears in 3 (mean deviation is
0.223 Å).
The degree of delocalization of the electron densities in
these structures is also reflected by the deviation of chalcogen
atom of the terminal PdE moiety from the central plane
mentioned above. This deviation is 0.371 and 0.485 Å for
2, 0.482 Å for 5, and 1.885 Å for 3, respectively. In all three
complexes, the In atom has a distorted trigonal-bipyramidal
environment with the methyl groups and N(1) from the
triazole ring occupying the equatorial plane (sum of the
angles: 359.8° and 360.0° (2), 359.1° (3), and 360° (5)).
The axial positions are occupied by a chalcogen atom and
the N(2) belonging to the second triazole ring of the dimer,
in which case significantly bent angles (157.3° and 155.7°
(2), 161.8° (3), and 158.4° (5)) are observed.
(8) Addition of stoichiometric amounts of H2O to a boiling solution of 4
in THF resulted merely in the isolation of 1c; the same result was
observed by bubbling air through the solution at ambient temperature
and at 65 °C. In a similar manner, addition of stoichiometric amounts
of H2O to a boiling solution of 1c in THF did not lead to the chalcogen
exchange, even when dry HCl was added as a catalyst. Although,
oxidation of 1c was successful with H2O2, it led to the rapid deposition
of red selenium and formation of an inseparable mixture of oxidation
compounds. For a similar chalcogen exchange reaction involving Pd
E groups, see Hong, F.-E.; Chang, Y.-C.; Chang, R.-E.; Chen, S.-C.;
Ko, B.-T. Organometallics 2002, 21, 961-967.
The equatorial In-N(1) bond (2.297 and 2.302 (2), 2.280
(3), and 2.312 Å (5)) is common for the five- and six-
Inorganic Chemistry, Vol. 45, No. 13, 2006 5169

Moya-Cabrera et al.
Table 1. Crystal Data and Structure Refinement for Compounds 2, 3, and 5·2THF
compound
2
3
5‚2THF
formula
fw
C56H52In2N6O4P4
1226.56
C56H52In2N6P4S4
1290.80
C64H68In2N6O4P4Se2
1496.68
cryst syst
triclinic
triclinic
triclinic
space group
a, Å
b, Å
P1h
P1h
P1h
12.845(2)
15.074(3)
16.198(3)
67.03(3)
11.431(3)
11.503(3)
11.741(3)
86.24(3)
8.266(2)
12.569(3)
16.847(3)
74.98(3)
79.71(3)
72.69(3)
1604(1)
1
1.549
8.389
c, Å
R, deg
â, deg
γ, deg
V, Å3
Z
70.30(3)
73.19(3)
2673 (1)
2
1.524
8.442
1240
0.11 × 0.02 × 0.01
3.06 to 56.92
18 883
85.73(3)
63.71(3)
1379(1)
1
1.554
9.534
652
0.15 × 0.04 × 0.01
3.78 to 57.89
13 247
F
calcld., g‚cm-3
µ, mm-1
F(000)
752
cryst size, mm3
θ range for data collection, deg
no. of reflns collected
0.15 × 0.04 × 0.02
2.73 to 57.81
12 903
no. of indep. reflns (Rint
)
6911 (0.0462)
6911/0/653
1.022
0.0569, 0.1380
0.0826, 0.1546
3.933/-0.994
3659 (0.0221)
3659/0/328
1.058
0.0171, 0.0444
0.0175, 0.0459
0.338/-0.304
4224 (0.0350)
4224/0/372
1.046
0.0320, 0.0701
0.0422, 0.0737
1.594/ -0.486
no. of data/restraints/params
GOF on F2
R1,a wR2b (I > 2σ(I))
R1,a wR2b (all data)
largest diff. peak/hole, e‚Å-3
2
2
2
a R1 ) ∑||Fo| - |Fc||/∑|Fo|. b wR2 ) [∑w(Fo - Fc )2/∑w(Fo )2]1/2
.
Table 2. Selected Bond Distances (Å) and Angles (deg) for
Compounds 2, 3, and 5
(3), and 2.499 Å (5)) belonging to the In2N4 core. All the
In-N bond lengths are significantly longer than those found
in the related (InMe2)2(µ-pz)2 (av 2.209) and (InCl2)2(µ-
4e
Compound 2
molecule a
3-(2-pyridyl)-1H-pz)2(DMF)2 4d (av 2.209). The In-Me bond
lengths are similar in all three compounds (av 2.155 (2), av
2.138 (3), and av 2.147 Å (5)) and are comparable to those
in (InMe2)2(µ-pz)2 4e (av 2.144 Å). Furthermore, these bond
lengths belong to the shorter ones reported in the CCDC
database (see In-Me bond length histogram from CCDC in
the Supporting Information, Figure S2).
In(1)-O(1)
In(1)-N(1)
In(1)-N(2A)
In(1)-C(27)
In(1)-C(28)
N(1)-N(2)
N(2)-N(3)
P(1)-O(1)
P(2)-O(2)
molecule b
In(2)-O(3)
In(2)-N(4)
In(2)-N(5A)
In(2)-C(55)
In(2)-C(56)
N(4)-N(5)
N(5)-N(6)
P(3)-O(3)
P(4)-O(4)
2.318(5)
2.297(6)
2.465(6)
2.145(9)
2.132(8)
1.328(9)
1.333(8)
1.505(5)
1.480(6)
N(1)-In(1)-N(2A)
C(27)-In(1)-C(28)
N(1)-In(1)-C(27)
N(1)-In(1)-C(28)
N(1)-In(1)-O(1)
N(2A)-In(1)-O(1)
P(1)-O(1)-In(1)
82.6(2)
140.5(4)
108.1(3)
111.2(3)
74.8(2)
157.3(2)
122.8(3)
The average N-N distances within the triazole ring for
all three compounds are almost identical (1.332 (2), 1.333
(3), and 1.338 Å (5)). Thus, the differences in the In-In
separations (4.90 and 4.96 (2), 4.93 (3), and 4.88 Å (5)) are
mainly due to the variation of the In-N bond lengths and
inner angles of the In2N4 ring system. The sums for these
inner angles (the theoretical value for a planar, six-membered
ring cores is 720°) are 719.8° and 720.0° (2), 711.8° (3),
and 716.2° (5), respectively. The In-O bond lengths in 2
(2.318 and 2.319 Å) and 5 (2.336 Å) have similar values
and when taking into account the difference of the covalent
radii for the oxygen (0.68 Å) and sulfur atoms (1.02 Å) these
are comparable also to the In-S bond length in 3 (2.780
Å).9 (For more details about the selected bond lengths for 2,
3, and 5 see Table 2)
2.319(5)
2.302(6)
2.495(6)
2.158(8)
2.186(7)
1.333(8)
1.334(9)
1.504(6)
1.484(5)
N(4)-In(2)-N(5A)
C(55)-In(2)-C(56)
N(4)-In(2)-C(55)
N(4)-In(2)-C(56)
N(4)-In(2)-O(3)
N(5A)-In(2)-O(3)
P(3)-O(3)-In(2)
81.7(2)
135.8(3)
112.4(3)
111.8(3)
74.0(2)
155.7(2)
123.2(3)
Compound 3
In(1)-S(1)
In(1)-N(1)
In(1)-N(2A)
In(1)-C(27)
In(1)-C(28)
N(1)-N(2)
N(2)-N(3)
P(1)-S(1)
2.780(1)
2.280(2)
2.583(2)
2.140(2)
2.136(2)
1.339(2)
1.327(3)
1.986(1)
1.948(1)
N(1)-In(1)-N(2A)
C(27)-In(1)-C(28)
N(1)-In(1)-C(27)
N(1)-In(1)-C(28)
N(1)-In(1)-S(1)
N(2A)-In(1)-S(1)
P(1)-S(1)-In(1)
83.5(1)
141.6(1)
109.9(1)
107.6(1)
78.3(1)
161.8(1)
96.7(4)
P(2)-S(2)
These In-E bond lengths are the longest ones observed
so far for any In-E-P-moiety-containing system. The
P-O(In) bond lengths (1.505 and 1.504 Å for 2; 1.515 Å
for 5) are slightly longer than those of the terminal PdO
(1.480 and 1.482 Å for 2), thus confirming the high degree
of electron delocalization in 2 and 5. Similar effects can be
also found in 3 for the P-S(In) (1.986 Å) and PdS bonds
(1.948 Å), but in this case, the difference is higher (for the
Compound 5
In(1)-O(1)
In(1)-N(1)
In(1)-N(2A)
In(1)-C(27)
In(1)-C(28)
N(1)-N(2)
N(2)-N(3)
P(1)-O(1)
P(2)-Se(1)
2.336(3)
2.311(4)
2.499(6)
2.142(5)
2.152(5)
1.345(5)
1.331(5)
1.515(3)
2.090(2)
N(1)-In(1)-N(2A)
C(27)-In(1)-C(28)
N(1)-In(1)-C(27)
N(1)-In(1)-C(28)
N(1)-In(1)-O(1)
N(2A)-In(1)-O(1)
P(1)-O(1)-In(1)
84.7(1)
142.5(2)
107.2(2)
110.3(2)
73.8(1)
158.4(1)
120.5(2)
membered rings (InNCPE and In2N4) and is shorter than the
In-N(2) in the axial position (2.465 and 2.495 (2), 2.583
(9) For a table of covalent atomic radii, see the web page of the Cambridge
Structural Database: http://www.ccdc.cam.ac.uk/products/csd/radii/.
5170 Inorganic Chemistry, Vol. 45, No. 13, 2006

Unusual In2N4 Cores in Triazole-Based Complexes
histograms of (P)E-In and P-E terminal bond lengths see
Figure S2 in the Supporting Information).
Acknowledgment. M.M.-C. thanks the DGAPA-UNAM
(PAPIIT Grant No. IN105203) for financial support. V.J.
thanks the UNAM for his postdoctoral fellowship. This paper
is dedicated to Professor Raymundo Cea-Olivares on the
occasion of his 55th birthday.
Conclusion
In summary, we explored the bonding properties of the
multidentate ligands [4,5-(P(E)Ph2)2tz] (E ) O, S, Se) with
indium. The results show that this ligand is capable of
achieving unconventional phosphoranyl complexes which
contain free PdE reaction sites that can be utilized for further
transformation or complexation reactions. Although the
formation mechanism of 5 remains unclear, further research
on this issue is currently underway.
Supporting Information Available: Figure S1 featuring mol-
ecule 2 of compound 2; histograms from CCDC; and X-ray data
(CIF) for 2, 3, and 5. This material is available free of charge via
the Internet at http://pubs.acs.org.
IC051567P
Inorganic Chemistry, Vol. 45, No. 13, 2006 5171