Oxidation of carbene-derived selenium diiodide with silver tetrafluoroborate - Isolation of iodonium ion complexes with selones

Article abstract of DOI:10.1002/ejic.201201238

The oxidation reactions of diiodoselones 10a and 10b with silver tetrafluoroborate afford linear complexes of iodonium ions with selones 13a and 13b. The decomposition of the tellurium tetraiodide adduct with benzimidazolin-2-selone (12) in chloroform also affords a similar iodonium ion complex 13c. Crystal structure analysis of 13a-13c shows interesting supramolecular formation by C-H...F, C-H...Br, C-H...I, Se...π, and I...π interactions. Copyright

Full text of DOI:10.1002/ejic.201201238

FULL PAPER
DOI:10.1002/ejic.201201238
Oxidation of Carbene-Derived Selenium Diiodide with
Silver Tetrafluoroborate – Isolation of Iodonium Ion
Complexes with Selones
Sudesh T. Manjare,[a] Harkesh B. Singh,*[a] and Ray J. Butcher[b]
Keywords: Iodine / Tellurium / Carbenes / Selenium
The oxidation reactions of diiodoselones 10a and 10b with
silver tetrafluoroborate afford linear complexes of iodonium
ions with selones 13a and 13b. The decomposition of the
tellurium tetraiodide adduct with benzimidazolin-2-selone
(12) in chloroform also affords a similar iodonium ion com-
plex 13c. Crystal structure analysis of 13a–13c shows inter-
esting supramolecular formation by C–H···F, C–H···Br,
C–H···I, Se···π, and I···π interactions.
selenides reacted with iodine in different amounts (1:1,
1:1.5, 1:2.5, 1:4 and 1:5 ratios) to give SeǞI bonds in ad-
ducts with various compositions.
Introduction
Hypervalent iodine compounds are of considerable cur-
rent interest because of their use in organic synthesis as
highly selective oxidizing reagents[1,2] and effective photoin-
itiators in the cationic polymerization of epoxy and vinyl
ether monomers.[3] Also, thiones[4] and thioureas[5] exhibit
interesting antithyroid activity by iodine complexation in
vivo.[6,7] There are many reports on the synthesis of iod-
onium ion complexes with various ligands.[2,6a,8–10] Deutsch
and co-workers have synthesized an iodonium ion complex
by the reaction of I+-donating reagents (N-iodosuccinimide/
molecular iodine/iodine nitrate, etc.) with the (thiolato)-
cobalt complex [(en)2Co(SCH2CH2NH2)]2+ (en = ethyl-
enediamine).[11] Hadjiliadis and co-workers reported the
synthesis of a mixed neutral and ionic iodine adduct of a
benzazole-2-thione 1 by the treatment of the appropriate
thione with iodine in a 1:1 or 1:2 ratio.[12] The group also
synthesized 2 by the reaction of FeCl3·6H2O and thione
with a dichloromethane solution of iodine. Devillanova and
co-workers have reported the first example of iodonium ion
complex with benzothiazole-2-selone (3), which was formed
by the treatment of benzothiazole-2-selone with iodine in a
1:1 molar ratio in dichloromethane (Figure 1).[13] Du Mont
and co-workers have reported the synthesis of iodoseleno-
phosphonium cations 4 and 5 by treating phosphane
selenides with iodine (in 1:1 and 1:1.5 ratios, respec-
tively).[14] It has been suggested that the trialkylphosphane
Figure 1. Iodonium ion complexes.
Recently, it has been shown that imidazole-selones can
be easily converted to cationic diselenides.[15,16] Kuhn and
co-workers reported that the oxidation reaction of diiodo-
selone 6 with silver tetrafluoroborate in tetrahydrofuran
(THF) gave cationic diselenide 7 with tetrafluoroborate
counteranion (Scheme 1).[15] The same group has isolated
ionic compound 9 from the reaction of selone 8 with iodine
in THF.
We have been interested in the synthesis of cationic di-
selenides based on benzimidazolin-2-selone to study their
glutathione peroxide-like (GPx-like) activity and to com-
pare that with the GPx-like activities of reported neutral
diselenides.[17] Recently, we have reported that the at-
tempted synthesis of cationic diselenides by the reaction of
benzimidazolin-2-dihaloselones with elemental tellurium
afforded tellurium tetrahalide adducts with N-heterocyclic
carbene (NHC) derived selones instead of the expected cat-
ionic diselenides.[18] Therefore, we changed our strategy for
the synthesis of new cationic diselenides. In this article, we
describe our attempts to synthesize cationic diselenides,
which afforded the first iodonium ion coordinated with
[a] Department of Chemistry, Indian Institute of Technology,
Bombay, Mumbai 400076, India
Fax: +91-22-2572-3480
E-mail: chhbsia@chem.iitb.ac.in
Homepage: http://www.chem.iitb.ac.in/~chhbsia
[b] Department of Chemistry, Howard University,
Washington, DC 20059, USA
Supporting information for this article is available on the
WWW under http://dx.doi.org/10.1002/ejic.201201238.
Eur. J. Inorg. Chem. 2013, 2161–2166
2161
© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

www.eurjic.org
FULL PAPER
vered from the reaction mixture as the major component.
Presumably, this is a redox reaction in which SeIV is reduced
to SeII and I– is oxidized to I+. These observations are quite
different from those reported by Kuhn and co-workers.[15]
The synthesis of cationic diselenide was also attempted by
the method reported in the literature[20] from the reaction
of 1,3-dibutyl-1H-benzo[d]imidazole-2(3H)-selone with
bromine (2:1 ratio) in acetonitrile. However, the desired dis-
elenide was not formed; instead, 1,3-dibutyl-1H-benzo[d]-
imidazole-2(3H)-dibromoselone was obtained as the prod-
uct.[18]
The tellurium tetraiodide adduct of selone 12 was syn-
thesized by the reaction of 1-(2-bromobenzyl)-3-isopropyl-
1H-benzo[d]imidazole-2(3H)-diiodoselone with elemental
tellurium.[18] The tellurium tetraiodide adduct was poorly
soluble in common organic solvents. Attempts were made
to dissolve 12 in chloroform by heating the solution. When
the solution was kept at room temperature for 2 d, it gave
13c as a dark red shiny crystalline solid (Scheme 2) with
Scheme 1. Synthesis of cationic diselenides and related derivatives.
NHC-derived selones. These complexes show interesting
supramolecular assemblies in their crystal packing di-
agrams, which are also being discussed here.
–
I3 as the counteranion in 26% yield, and the remaining
compound 12 was recovered from the solution. This is a
disproportionation reaction of the tellurium tetraiodide ad-
duct, in which TeIV is converted to Te0 and I– is converted
Results and Discussion
Synthesis
–
to I+ and I3 to give an iodonium ion complex with NHC-
derived selone and I3– anions. Compounds 13a–c were char-
acterized by elemental analysis, common spectroscopic
techniques, and single-crystal X-ray analysis (vide infra).
Although Kuhn and co-workers have proposed the for-
mation of an iodonium ion complex with NHC-derived se-
lones,[15] the isolation and structure of an iodonium ion
complex with an NHC-derived selone has not been re-
ported so far.
The syntheses of the cationic diselenides 11a and 11b
were attempted by following the method reported by Kuhn
and co-workers.[15] Diiodoselones 10a and 10b were pre-
pared in excellent yields (ca. 80%) by the reaction of iodine
with
1-(2-bromobenzyl)-3-butyl-1H-benzo[d]imidazole-
2(3H)-selone
and
1-(2-bromobenzyl)-3-isopropyl-1H-
benzo[d]imidazole-2(3H)-selone, respectively, in THF.[19]
Unexpectedly, the reaction of diiodoselone 10a with silver
tetrafluoroborate in THF afforded the iodonium ion com-
1
The H and 13C NMR spectra of 13a and 13b did not
plex 13a instead of the desired cationic diselenide 11a show significant differences in the chemical shifts compared
(Scheme 2). The analogous reaction involving diiodoselone with those of the corresponding precursors 10a and 10b,
10b also gave a minor amount of a similar iodonium ion respectively. The 77Se NMR spectrum of 13a showed a sig-
complex 13b, and unreacted diiodoselone (10b) was reco- nal at δ = 249 ppm, which is downfield shifted compared to
Scheme 2. Synthesis of iodonium ion complexes of selone.
Eur. J. Inorg. Chem. 2013, 2161–2166
2162
© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

www.eurjic.org
FULL PAPER
that of the diiodoselone 10a (δ = 218 ppm). However, the methylbenzothiazole-2(3H)-selone donors. This complex
77Se NMR signal for the iodonium ion coordinated with tri- showed a significant difference in the two I–Se bond lengths
tert-butylphosphane selenide (δ ≈ –29 ppm) is significantly [2.800(1) and 2.719(1) Å], and the Se–I–Se bond angle
different.[14b] The difference in the 77Se NMR chemical [178.02(2)°] is larger than the bond angle [173.54(6)°] of
shifts of 13a (in non-coordinating solvent CDCl3, δ = 13a. In 13b, the I–Se bond lengths [2.798(1) Å] are equal
249 ppm) and 13b (δ = 107 ppm) may be due to coordinat- and the Se–I–Se* bond angle (180.0°) is exactly linear, as is
ing [D6]DMSO solvent. The mass spectrum of the com- required by the crystallographic symmetry. This is in con-
pound shows [M + Na]+ peaks with the expected isotopic trast with 13a, in which the bond angle deviates from linear-
pattern. Interestingly, the iodonium ion in 13b is stabilized ity. The benzimidazole rings are trans to each other. The
by two selones, and the positive charge is neutralized by a counteranion is severely disordered in the crystal lattice and
–
–
–
–
mixed BF4 /I3 anion with an occupancy ratio of 0.635/ was fixed as BF4 /I3 (compositional disorder) with an oc-
0.365 (vide infra). A plausible mechanism for the formation cupancy ratio of 0.635/0.365. Interestingly, the iodonium
of iodonium ion complex has been suggested (Scheme S1 in ion complex stabilized by the same selone (13c) is iso-
the Supporting Information).
structural with 13b and shows equal Se–I bond lengths
To validate the difference in reactivity of benzimidazolin- [2.804(7) Å] and a linear Se–I–Se* bond angle [180.0(1)°].
2-diiodoselones with silver tetrafluoroborate compared The only difference between 13b and 13c is the anions; in
–
–
–
with the imidazolin-2-diiodoselone reported by Kuhn and 13b the anion is mixed BF4 /I3 , and in 13c the anion is I3
co-workers,[15] the structural features were examined and (Figure 2, bottom).
compared. The molecular structures of benzimidazolin-2-
selones show C–Se bond lengths from 1.825 to 1.833 Å;[19]
however, for the imidazolin-2-selones, the C–Se bond
lengths range from 1.843 to 1.853 Å.[21] Earlier, by using
DFT calculations, we demonstrated that the C–Se bond of
the
1-(2-bromobenzyl)-3-methyl-1H-benzo[d]imidazole-
2(3H)-selone system (1.833 Å) is shorter than that of the 1-
(2-bromobenzyl)-3-methyl-1H-imidazole-2(3H)-selone sys-
tem (1.843 Å). The Se bond index (1.77) is larger in the
benzimidazolin-2-selone system than in the imidazolin-2-se-
lone system (1.68).[19] On the basis of these facts, we in-
ferred that the C–Se bond in the benzimidazolin-2-selone
system is stronger than that in imidazolin-2-selones. This
may be the cause of the poor reactivity of benzimidazolin-
2-selones, which are not further oxidized to cationic diselen-
ides.
Molecular and Supramolecular Structures of Compounds
13a, 13b and 13c
The molecular structures of 13b and 13c (13a see Fig-
ures S13, S14 and Tables S1, S2) are depicted in Figure 2,
and selected bond lengths and bond angles are given in
Table 1. In 13b and 13c, the iodonium ion has a linear geo-
metry. The geometry around the central iodine atom can
also be described as trigonal-bipyramidal by considering
that the three lone pairs of electrons are in equatorial posi-
tions and the two bonds with the selenium atom are in the
axial positions. However, in compound 13a the Se–I–Se*
bond angle [173.54(6)°] deviates slightly from linearity, and
the I–Se and I–Se* bond lengths [2.773(1) Å] are symmetric
(Figure 2, top). Devillanova and co-workers[13] have re-
Figure 2. Top: Molecular structure of 13b. Bottom: Molecular
structure of 13c. Hydrogen atoms are omitted for clarity (except
ported the structure of an iodonium ion trapped with N- those involved in interactions).
Table 1. Selected bond lengths and bond angles of 13b and 13c.
Compound
Bond length [Å]
Bond angle [°]
13b
13c
Se–C1 1.890(7)
Se–C1 1.877(5)
I–Se 2.798(8)
I–Se 2.804(7)
I1A–I1B 2.903(2)
I1–I2 2.909(5)
Se1–I–Se 180.00(4)
Se2*–I–Se 180.0
C1–Se–I 99.2(2)
C1–Se–I 99.28(2)
Eur. J. Inorg. Chem. 2013, 2161–2166
2163
© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

www.eurjic.org
FULL PAPER
The crystal packing diagram for 13a shows three types connected by strong C–H···F interactions. The overall ef-
of hydrogen-bonding interactions C–H3A···F1 [2.500(8) Å], fects of these interactions lead to the formation of a 3D
C–H3A···F2 [2.546(13) Å], and C–H8A···F2 [2.257(17) Å]. supramolecular assembly with 2D void channels along the
All these distances are longer than the covalent radii and b axis (Figure 3, top). Similarly, in 13c, two types of inter-
smaller than the van der Waals radii.[22] These interactions molecular interactions [Se···π* 3.578(7) Å and I···π*
are responsible for the formation of a 2D structure, which 3.659(6) Å] are responsible for the formation of a 2D net-
further interacts to form 3D packing in the crystal (Fig- work (Figure 3, bottom).
ures S14 and S15). Packing diagrams for 13b show one layer
–
–
containing BF4 counteranions and the other layer with I3
Conclusions
anions. The crystal packing diagram shows C–H5A···I1A
(3.046 Å), C–H16C···F1 (2.431 Å), C–H4A···F2 (2.564 Å),
and Se···I1A [3.983(1) Å] intermolecular interactions. The
Rare complexes of iodonium ions with benzimidazolin-
2-selones (13a,b) have been isolated by using silver tetra-
fluoroborate as an oxidizing agent. Also, the iodonium ion
complex 13c was isolated from the tellurium tetraiodide ad-
duct. The crystal packing of the iodonium ion complexes
show interesting supramolecular assemblies formed by
C–H···F, C–H···I, Se···I, Se···π, and I···π intermolecular in-
teractions.
–
two terminal iodine atoms of the I3 anion have weak sec-
ondary bonding interactions (SBIs) with selenium atoms of
two different molecules and form a zigzag ribbon-like ar-
rangement (Figures S16 and S17). These ribbons are inter-
Experimental Section
General: All manipulations were carried out under nitrogen or ar-
gon by using standard Schlenk techniques unless otherwise noted.
Solvents were purified and dried by standard procedures and were
distilled prior to use. Melting points were recorded with a Veego
1
VMP-I melting point apparatus in capillary tubes. H (400 MHz)
and 13C (100.56 MHz) NMR spectra were recorded with Varian
VXR 400S and Bruker AV 400 spectrometers at 25 °C. The 77Se
(57.22 and 76.3 MHz) spectra were recorded with Varian VXR
300S and Bruker AV 400 spectrometers. Chemical shifts are cited
with respect to Me4Si as internal standard (1H and 13C) and Me2Se
(77Se) as external standard. Elemental analyses were performed
with a Carlo Erba Model 1106 elemental analyzer. ESI mass spec-
tra were recorded with a Q-Tof Micromass (YA-105) mass spec-
trometer.
Compound 13a: In a round-bottomed flask, compound 10a (80 mg,
0.12 mmol) was dissolved in THF (20 mL), and AgBF4 (40 mg,
0.24 mmol) was added. The reaction mixture was stirred at room
temperature for 2 h and then filtered through Celite and washed
with THF. The collected filtrate was concentrated with a rotary
evaporator. The crude product was dissolved in THF and petro-
leum ether, and the solution was kept at –25 °C overnight. The
brownish solid product 13a was collected and dried in vacuo. Yield:
100 mg (75%). M.p. 95 °C (decomposed). 1H NMR (400 MHz,
CDCl3): δ = 7.81 (d, J = 8 Hz, 1 H), 7.62 (dd, J = 8, 1.2 Hz, 1 H),
7.54 (m, 1 H), 7.43 (m, 2 H), 7.09 (m, 1 H), 7.01 (m, 1 H), 6.61 (d,
J = 6.4 Hz, 1 H), 5.82 (s, 2 H), 4.58 (t, J = 8 Hz, 2 H), 1.90 (m, 2
H), 1.44 (m, 2 H), 0.94 (t, J = 8 Hz, 3 H) ppm. 13C NMR
(100 MHz, CDCl3): δ = 155.3 (NCN), 134.7, 134.5, 134.4, 134.3,
131.1, 129.1, 129.0, 127.4, 123.6, 113.6, 113.4, 52.5, 48.5, 32.1, 21.1,
14.2 ppm. 77Se NMR (57 MHz, CDCl3): δ = 249 ppm. ESI-MS:
m/z = 1078 [M + H2O]+. C36H38BBr2F4IN4Se2 (1058.16): calcd. C
40.86, H 3.62, N 5.29; found C 40.63, H 3.51, N 6.04.
Compound 13b: The same synthetic procedure as that used for 13a
was employed here. The reagents used were 10b (140 mg,
0.23 mmol) in THF (20 mL) and AgBF4 (90 mg, 0.46 mmol). The
filtrate was concentrated to one third of its volume and then slowly
concentrated in air for 30 h. Some dark red crystalline solid 13b
was collected and dried in vacuo. Unreacted diiodoselone 10b was
the major component recovered from the reaction mixture. Yield:
–
Figure 3. Top: Crystal packing diagram of 13b containing I3 and
BF4– counteranion layers. Bottom: Crystal packing diagram of 13c
containing I3 counteranion layers. Hydrogen atoms are omitted
–
for clarity (except those involved in interactions).
Eur. J. Inorg. Chem. 2013, 2161–2166
2164
© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

www.eurjic.org
FULL PAPER
Table 2. Details of the X-ray data collection parameters for 13b and 13c.
13b
13c
Empirical formula
M
Crystal system
Space group
a [Å]
b [Å]
c [Å]
C34H34B1.27Br2F5.07 2.10
1192.94
I
N4Se2
C34H34Br2I4N4Se2
1324.69
triclinic
triclinic
¯
¯
P1
P1
8.149
8.408
14.908
99.47
93.15
102.16
980.7
1
8.2025(3)
8.5365(4)
14.9601(8)
99.628(4)
92.801(4)
101.900(4)
1006.79(8)
1
α [°]
β [°]
γ [°]
V [Å3]
Z
Size [mm]
ρcalcd. [Mgm–3]
μ [mm–1]
Reflections collected
Observed reflections
R1 [IϾ2σ(I)]
wR2 [IϾ2σ(I)]
0.51ϫ0.39ϫ0.32
2.020
5.630
7997
4475
0.0604
0.1275
0.8568ϫ0.6363ϫ0.1971
2.185
6.859
12510
6602
0.0599
0.1024
1
48 mg (19%). M.p. 230–232 °C. H NMR (400 MHz, CDCl3): δ = bridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/
7.82 (d, J = 8.3 Hz, 1 H), 7.68 (dd, J = 7.5, 1.5 Hz, 1 H), 7.50 (t,
J = 7.3 Hz, 1 H), 7.42 (t, J = 7.3 Hz, 1 H), 7.31 (d, J = 8.3 Hz, 1
H), 7.23 (m, 2 H), 7.12 (br d, J = 7.0 Hz, 1 H), 5.92 (s, 2 H), 5.81
(m, 1 H), 1.85 (d, J = 7.0 Hz, 6 H) ppm. 13C NMR (100 MHz,
CDCl3): δ = 150.5 (NCN), 133.5, 132.5, 131.3, 130.3, 128.7,
128.3, 126.7, 126.5, 122.6, 114.1, 113.1, 55.4, 52.3, 20.8 ppm.
data_request/cif.
Supporting Information (see footnote on the first page of this arti-
cle): 1H, 13C and 77Se NMR spectra, mass spectra and elemental
analysis data of newly synthesized compounds, molecular structure
of 13a, crystal packing diagrams for 13a and 13b and a plausible
mechanism for the formation of iodonium ion complex.
77Se NMR (57 MHz, [D6]DMSO):
calcd. for C34H35N4Br2ISe2 943.8604; found 943.8595.
C34H34B1.27Br2F5.07 2.10
δ = 107 ppm. HRMS:
I
N4Se2 (1192.95): calcd. C 34.23, H 2.87, N Acknowledgments
4.70; found C 36.48, H 2.73, N 4.96.
H. B. S. gratefully acknowledges the Department of Science and
Technology, New Delhi for the Ramanna Fellowship. S. T. M. is
thankful to the Council of Scientific and Industrial Research
(CSIR), New Delhi for a Senior Research Fellowship (SRF) and
the Sophisticated Analytical Instrument Facility (SAIF), IITB for
spectroscopic data analysis.
Compound 13c: An attempt was made to dissolve the dark red tel-
lurium tetraiodide adduct 12 (50 mg, 0.034 mmol) in hot chloro-
form (0.5 mL). The solution was kept at room temperature for 2 d,
and a minor amount of red crystalline solid 13c formed. The re-
maining 12 was recovered from the solution. Yield: 12 mg (26%).
1H NMR (400 MHz, [D6]DMSO): δ = 7.91 (dd, J = 8.0, J = 4.7 Hz,
1 H), 7.71–7.67 (m, 1 H), 7.38–7.30 (m, 3 H), 7.29–7.18 (m, 2 H),
6.51 (dd, J = 5.4, J = 2.2 Hz, 1 H), 5.7 (s, 2 H), 5.64 (m, 1 H),
1.61 (d, J = 7.0 Hz, 6 H) ppm. HRMS: calcd. for C34H34Br2IN4Se2
942.8565, found 942.8543. C34H34Br2I4N4Se2 (1324.02): calcd. C
30.84, H 2.59, N 4.23; found C 30.82, H 2.17, N 5.37.
[1] a) A. Varvoglis, Chem. Soc. Rev. 1981, 10, 377–407; b) V. N.
Nemykin, A. Y. Koposov, B. C. Netzel, M. S. Yusubov, V. V.
Zhdankin, Inorg. Chem. 2009, 48, 4908–4917; c) R. M. Mori-
arty, O. Prakash, Acc. Chem. Res. 1986, 19, 244–250; d) T.
Wirth, U. H. Hirt, Synthesis 1999, 1271–1287; e) R. D. Rich-
ardson, J. M. Zayed, S. Altermann, D. Smith, T. Wirth, Angew.
Chem. 2007, 119, 6649; Angew. Chem. Int. Ed. 2007, 46, 6529–
6532; f) S. Schäfer, T. Wirth, Angew. Chem. 2010, 122, 2846;
Angew. Chem. Int. Ed. 2010, 49, 2786–2789.
[2] a) M. Ochiai, K. Miyamoto, M. Shiro, T. Ozawa, K. Yamagu-
chi, J. Am. Chem. Soc. 2003, 125, 13006–13007; b) P. P. Thot-
tumkara, T. K. Vinod, Org. Lett. 2010, 12, 5640–5643.
[3] W. D. Cook, S. Chen, F. Chen, M. U. Kahveci, Y. Yagci, J.
Polym. Sci. Polym. Chem. Ed. 2009, 5474–5487.
[4] a) G. B. Ansell, D. M. Forkey, D. W. Moore, J. Chem. Soc. C
1970, 56–57; b) B. L. Benac, E. M. Burgess, A. J. Arduengo,
Org. Synth. 1986, 64, 92–93; c) F. E. Hahn, L. Wittenbecher,
R. Boese, D. Bläser, Chem. Eur. J. 1999, 5, 1931–1935.
[5] S. Husebye, J. W. George, Inorg. Chem. 1969, 8, 313–319.
[6] a) P. D. Boyle, J. Christie, T. Dyer, S. M. Godfrey, I. R. How-
son, C. McArthur, B. Omar, R. G. Pritchard, G. R. Williams,
J. Chem. Soc., Dalton Trans. 2000, 3106–3112; and references
cited therein b) J. F. Lagorce, F. Comby, J. Buxeraud, C. Raby,
Eur. J. Med. Chem. 1992, 27, 359–368; c) J. Buxeraud, A. B.
Absil, J. Claude, C. Raby, G. Catazano, C. Beck, F. Claude,
Eur. J. Med. Chem. Chim. Ther. 1985, 20, 43–50.
Single-Crystal X-ray Crystallographic Data: The single-crystal X-
ray diffraction measurements were performed with an Oxford Dif-
fraction Gemini diffractometer. The data were corrected for Lo-
rentz, polarization and absorption effects. The structures were de-
termined by routine heavy-atom and Fourier methods by using
SHELXS97[23] and refined by full-matrix least-squares methods.
The non-hydrogen atoms were refined anisotropically, and the hy-
drogen atoms were refined with fixed isotropic thermal parameters
of 0.07 Å2 by using the SHELXL97[24] program. The hydrogen
atoms were partially located from difference electron density maps,
and the rest were fixed at predetermined positions. Scattering fac-
tors from common sources were used.[25] Details of the X-ray data
collection parameters are given in Table 2. The solvents used to
grow the crystals are listed below. Compounds 13a and 13b: THF
and petroleum ether (2:1), slow concentration at room temperature;
13c: [D3]chloroform, slow concentration at room temperature.
CCDC-882656 (for 13a), -882657 (for 13b) and -882658 (for 13c)
contain the supplementary crystallographic data for this
paper. These data can be obtained free of charge from The Cam-
Eur. J. Inorg. Chem. 2013, 2161–2166
2165
© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

www.eurjic.org
FULL PAPER
[7] a) F. Freeman, J. W. Ziller, H. N. Po, M. C. Keindl, J. Am.
Chem. Soc. 1988, 110, 2586–2591; b) F. H. Herbstein, W.
Schwotzer, J. Am. Chem. Soc. 1984, 106, 2367–2373.
[8] P. J. Stang, V. V. Zhdankin, A. M. Arif, J. Am. Chem. Soc.
1991, 113, 8997–8998.
[9] a) R. S. Brown, R. W. Nagorski, A. J. Bennet, R. E. D.
McClung, G. H. M. Aarts, M. Klobukowski, R. McDonald,
B. D. Santarsiero, J. Am. Chem. Soc. 1994, 116, 2448–2456; b)
S. Fox, R. T. Stibrany, J. A. Potenza, H. J. Schugar, Inorg.
Chim. Acta 2001, 316, 122–126.
[10] V. Daga, S. K. Hadjikakou, N. Hadjiliadis, M. Kubicki, J. H. Z.
dos Santos, I. S. Butler, Eur. J. Inorg. Chem. 2002, 1718–1728.
[11] D. L. Nosco, M. J. Heeg, M. D. Glick, R. C. Elder, E. Deutsch,
J. Am. Chem. Soc. 1980, 102, 7784–7786.
[12] G. J. Corban, S. K. Hadjikakou, N. Hadjiliadis, M. Kubicki,
E. R. T. Tiekink, I. S. Butler, E. Drougas, A. M. Kosmas, Inorg.
Chem. 2005, 44, 8617–8627.
Herbst-Irmer, U. Kilimann, F. T. Edelmann, J. Organomet.
Chem. 1992, 437, 299–305; c) Y. Nishibayashi, J. D. Singh, S.-
i. Fukuzawa, S. Uemura, J. Org. Chem. 1995, 60, 4114–4120;
d) S. R. Wilson, P. A. Zucker, R.-R. C. Huang, A. Spector, J.
Am. Chem. Soc. 1989, 111, 5936–5939; e) S. S. Zade, H. B.
Singh, R. J. Butcher, Angew. Chem. 2004, 116, 4613; Angew.
Chem. Int. Ed. 2004, 43, 4513–4515; f) G. Roy, M. Nethaji, G.
Mugesh, J. Am. Chem. Soc. 2004, 126, 2712–2713.
S. T. Manjare, H. B. Singh, R. J. Butcher, unpublished work.
S. T. Manjare, S. Sharma, H. B. Singh, R. J. Butcher, J. Or-
ganomet. Chem. 2012, 717, 61–74.
F. Bigoli, P. Deplano, F. A. Devillanova, V. Lippolis, M. L.
Mercuri, M. A. Pellinghelli, E. F. Trogu, Eur. J. Inorg. Chem.
1998, 137–141.
a) T. Kratz, G. Henkel, N. Kuhn, Z. Naturforsch. B 1993, 48,
973–977; b) G. Roy, D. Das, G. Mugesh, Inorg. Chim. Acta
2007, 360, 303–316.
[18]
[19]
[20]
[21]
[13] F. Demartin, P. Deplano, F. A. Devillanova, F. Isaia, V. Lip-
polis, G. Verani, Inorg. Chem. 1993, 32, 3694–3699.
[14] a) E. Seppälä, F. Ruthe, J. Jeske, W.-W. du Mont, P. G. Jones,
Chem. Commun. 1999, 1471–1472; b) W.-W. du Mont, M.
[22] a) M. Mantina, A. C. Chamberlin, R. Valero, C. J. Cramer,
D. G. Truhlar, J. Phys. Chem. A 2009, 113, 5806–5812; b) A.
Bondi, J. Phys. Chem. 1964, 68, 441–451.
Bätcher, C. Daniliuc, F. A. Devillanova, C. Druckenbrodt, J. [23] G. M. Sheldrick, SHELXS 97 Program for the Solution of
Jeske, P. G. Jones, V. Lippolis, F. Ruthe, E. Seppälä, Eur. J.
Inorg. Chem. 2008, 4562–4577.
[15] N. Kuhn, R. Fawazi, T. Kratz, M. Steimann, Phosphorus Sulfur
Silicon Relat. Elem. 1996, 112, 225–233.
[16] F. Bigoli, F. Demartin, P. Deplano, F. A. Devillanova, F. Isaia,
V. Lippolis, M. L. Mercuri, M. A. Pellinghelli, E. F. Trogu, In-
org. Chem. 1996, 35, 3194–3201.
[17] a) A. J. Mukherjee, S. S. Zade, H. B. Singh, R. B. Sunoj, Chem.
Rev. 2010, 110, 4357–4416; b) H. Gornitzka, S. Besser, R.
Crystal Structures, University of Göttingen, Göttingen, Ger-
many 1997.
[24] G. M. Sheldrick, SHELXL 97, Program for Refining Crystal
Structures, University of Göttingen, Göttingen, Germany
1997.
[25] D. T. Cromer, J. T. Waber, International Tables for X-ray Crys-
tallography, Kynoch Press, Birmingham, U.K., 1974.
Received: October 12, 2012
Published Online: February 20, 2013
Eur. J. Inorg. Chem. 2013, 2161–2166
2166
© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim