Synthesis, structure, and reactivity of intramolecularly coordinated organoantimony and organobismuth sulfides

Article abstract of DOI:10.1021/om801194h

Organoantimony(III) and organobismuth(III) sulfides, containing O,C,O-chelating ligands (L^1-3 = 2,6- (ROCH₂) ₂C₆H₃-, where R = Me (L¹), t-Bu (L²), or mesityl (L³)), [L^1-3MS]₂, where M = Sb (LM¹ (5), L² (6), L³ (7)) or M = Bi (L² (8)), were prepared by the reaction of parent organoantimony and organobismuth chlorides with Na₂S ? 9H₂O in toluene/water. All sulfides 5-8 were characterized by elemental analysis, electrospray ionization mass spectrometry, ¹H and ¹³C NMR spectroscopy, and X-ray diffraction techniques. Organoantimony sulfides 5-7 are stable both in solution and in the solid state in contrast to the organobismuth congener, which is stable at -30 °C but decomposes at ambient temperature. While the reaction of 5 and 7 with I₂ yielded the expected organoantimony iodides L^1,3Sbl₂ (L¹ (9), L ³ (10)), compound 6 containing ligand L³ gives the unexpected oxastibol 12 besides the intended diiodide L²SbI ₂ (11). The molecular structure of 12 in the solid state was determined by X-ray diffraction techniques and showed formation of an Sb-O covalent bond as a result of C-O ether bond cleavage.

Full text of DOI:10.1021/om801194h

1934
Organometallics 2009, 28, 1934–1941
Synthesis, Structure, and Reactivity of Intramolecularly
Coordinated Organoantimony and Organobismuth Sulfides
Marie Chovancova´,† Roman Jambor,† Alesˇ Ru˚zˇicˇka,† Robert Jira´sko,‡ Ivana Císarˇova´,§ and
Libor Dosta´l*,†
Departments of General and Inorganic Chemistry and of Analytical Chemistry, Faculty of Chemical
ˇ
Technology, UniVersity of Pardubice, na´m. Cs. Legií 565, CZ-532 10, Pardubice, and Faculty of Natural
Science, Charles UniVersity in Prague, HlaVoVa 2030, CZ-128 40, Prague 2, Czech Republic
ReceiVed December 18, 2008
Organoantimony(III) and organobismuth(III) sulfides, containing O,C,O-chelating ligands (L1-3 ) 2,6-
-
(ROCH2)2C6H3 , where R ) Me (L1), t-Bu (L2), or mesityl (L3)), [L1-3MS]2, where M ) Sb (L1 (5), L2
(6), L3 (7)) or M ) Bi (L2 (8)), were prepared by the reaction of parent organoantimony and organobismuth
chlorides with Na2S · 9H2O in toluene/water. All sulfides 5-8 were characterized by elemental analysis,
electrospray ionization mass spectrometry, 1H and 13C NMR spectroscopy, and X-ray diffraction techniques.
Organoantimony sulfides 5-7 are stable both in solution and in the solid state in contrast to the
organobismuth congener, which is stable at -30 °C but decomposes at ambient temperature. While the
reaction of 5 and 7 with I2 yielded the expected organoantimony iodides L1,3SbI2 (L1 (9), L3 (10)),
compound 6 containing ligand L2 gives the unexpected oxastibol 12 besides the intended diiodide L2SbI2
(11). The molecular structure of 12 in the solid state was determined by X-ray diffraction techniques and
showed formation of an Sb-O covalent bond as a result of C-O ether bond cleavage.
of the first examples of organoantimony difluorides,4 highly
Introduction
Lewis acidic organoantimony and organobismuth cations,5 and
compounds containing a M-M bond or terminal Sb-Se(Te)
The so-called Y,C,Y-chelating, or pincer, ligands [2,6-
(YCH2)2C6H3]- (Y ) N, O, P, S, etc.) have been shown to be
a very useful platform for the preparation of organometallic
compounds with both transition1 and main group2 metals. These
ligands often give special chemical and structural properties to
the coordinated central metal due to their ability to form two
more or less strong intramolecular M-Y dative bonds.
bonds.6
As a part of our continuing investigation of main group metal
complexes bearing Y,C,Y pincer ligands, we report here the
synthesis and structures of organoantimony and organobismuth
sulfides containing O,C,O pincer ligands. To date most of the
reported organoantimony and organobismuth sulfides contain
monodentate ligands.
Diorgano derivatives (type R2MSMR2, where R ) carbon-
bound ligand and M ) Sb or Bi)7 are monomeric, and
monorganoantimony and bismuth compounds form dimers to
tetramers (type [RMS]x, x ) 2 or 4) depending on the nature of
the substituent R. They often display ring-ring equilibrium in
solution.8 Use of a sterically demanding ligand allowed the
isolation of unusual Sb2S3, SbS5, SbS7, and Bi2S3 ring systems.9
Among the heavier pnictogens (in particular Sb and Bi), such
pincer ligands recently have found application. Organoantimony
and organobismuth halides containing O,C,O- or N,C,N-chelated
ligands display interesting structures depending both on the
ligand and on the halide used.3 These ligands allowed synthesis
* To whom correspondence should be addressed. E-mail: libor.dostal@
upce.cz. Fax: +420 466037068. Phone: +420 466037163.
(3) (a) Atwood, D. A.; Cowley, A. H.; Ruiz, J. Inorg. Chim. Acta 1992,
198-200, 271. (b) Dosta´l, L.; Císarˇova´, I.; Jambor, R.; Ru˚zˇicˇka, A.; Jira´sko,
R.; Holecˇek, J. Organometallics 2006, 25, 4366. (c) Soran, A.; Silvestru,
C.; Breunig, H. J.; Bala´zs, G.; Green, J. C. Organometallics 2007, 26, 1169.
(4) Dosta´l, L.; Jambor, R.; Ru˚zˇicˇka, A.; Jira´sko, R.; Císarˇova´, I.; Holecˇek,
J. J. Fluorine Chem. 2008, 129, 167.
(5) (a) Dosta´l, L.; Nova´k, P.; Jambor, R.; Ru˚zˇicˇka, A.; Císarˇova´, I.;
Jira´sko, R.; Holecˇek, J. Organometallics 2007, 26, 2911. (b) Dosta´l, L.
Unpublished results.
(6) (a) Balazs, L.; Breunig, H. J.; Lork, E.; Soran, A.; Silvestru, C. Inorg.
Chem. 2006, 45, 2341. (b) Dosta´l, L.; Jambor, R.; Ru˚zˇicˇka, A.; Holecˇek, J.
Organometallics 2008, 27, 2169. (c) Dosta´l, L.; Jambor, R.; Ru˚zˇicˇka, A.;
Lycˇka, A.; Brus, J.; de Proft, F. Organometallics 2008, 27, 6059.
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G.; Mundt, O.; Schwarz, W. Z. Anorg. Allg. Chem. 2000, 626, 1595. (b)
Breunig, H. J.; Jo¨nsson, M.; Ro¨sler, R.; Lork, E. Z. Anorg. Allg. Chem.
1999, 625, 2120. (c) Breunig, H. J.; Ghesner, I.; Lork, E. J. Organomet.
Chem. 2002, 664, 130. (d) Breunig, H. J.; Ebert, K. H.; Schulz, R. E.;
Wieber, M.; Sauer, I. Z. Naturforsch., B: Chem. Sci. 1995, 50, 735.
(8) (a) Mohammed, M. A.; Ebert, K. H.; Breunig, H. J. Z. Naturforsch.,
B: Chem. Sci. 1996, 51, 149. (b) Tokitoh, N.; Arai, Y.; Sasamori, T.; Takeda,
N.; Okazaki, R. Heteroat. Chem. 2001, 12, 244. (c) Breunig, H. J.; Kischkel,
H. Z. Naturforsch., B: Chem. Sci. 1981, 36, 1105.
† Department of General and Inorganic Chemistry, University of
Pardubice.
‡ Department of Analytical Chemistry, University of Pardubice.
§ Charles University in Prague.
(1) (a) Albrecht, M.; van Koten, G. Angew. Chem., Int. Ed. 2001, 40,
3750. (b) van der Boom, M. E.; Milstein, D. Chem. ReV. 2003, 103, 1759.
(c) van Koten, G. Pure Appl. Chem. 1989, 61, 1681. (d) Slagt, M. Q.; van
Zwieten, D. A. P.; Moerkerk, A. J. C. M.; Gebbing, R. J. M. K.; van Koten,
G. Coord. Chem. ReV. 2004, 248, 2275. (e) Gagliardo, M.; Snelders,
D. J. M.; Chase, P. A.; Gebbing, R. J. M. K.; van Klink, G. P. M.; van
Koten, G. Angew. Chem., Int. Ed. 2007, 46, 8558.
(2) (a) Gossage, R. A.; Jastrzebski, J. T. B. H.; van Koten, G. Angew.
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Jastrzebski, J. T. B. H.; Kooijman, H.; Lutz, M.; Spek, A. L.; Gossage,
R. A.; van Koten, G. Chem.sEur. J. 2004, 10, 253. (c) Jastrzebski,
J. T. B. H.; van Koten, G. AdV. Organomet. Chem. 1993, 35, 241. (d)
Chauhan, M.; Chuit, C.; Corriu, R. J. P.; Mehdi, A.; Reye, C. Organome-
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10.1021/om801194h CCC: $40.75
2009 American Chemical Society
Publication on Web 02/27/2009

Organoantimony and Organobismuth Sulfides
Organometallics, Vol. 28, No. 6, 2009 1935
Chart 1
Scheme 1. Preparation of Compound 3
Figure 1. ORTEP drawing (50% probability atomic displacement
ellipsoids, one of two independent molecules in the unit cell) of 3.
Hydrogen atoms have been omitted for clarity. Selected bond
distances (Å): Sb1-O1, 2.818(4); Sb1-O2, 2.553(4); Sb1-Cl1,
2.4098(12); Sb1-Cl2, 2.3924(12); Sb1-C1, 2.147(4). Selected
bond angles (deg): O1-Sb1-O2, 119.39(11); Cl1-Sb1-Cl2,
86.29(4);O1-Sb1-Cl1,71.59(8);O2-Sb1-Cl2,74.76(8);C1-Sb1-O1,
67.59(13); C1-Sb1-O2, 71.01(13); C1-Sb1-Cl1, 97.83(12);
C1-Sb1-Cl2, 94.77(13).
Table 1. Comparison of Bonding Lengths Sb-Y (Y ) O or N) (Å)
in Various Organoantimony Halides Containing Y,C,Y-Chelating
Ligands
Few examples of the use of chelating ligands for stabilization
of organoantimony sulfides have been reported. The only
examples of N,C-chelated organoantimony sulfides are [2-
(Me2NCH2)C6H3SbS]2, which is dimeric (forming a central
Sb2S2 ring) both in solution and in the solid state without any
ring-ring equilibrium, and a compound with a single µ-S bridge,
[2-(Me2NCH2)C6H4SbCl]2S.10 In the case of analogous orga-
nobismuth compounds, [2,6-(Me2NCH2)2C6H3BiS]2 and [2-(Me2-
NCH2)C6H4BiS]2 are the only examples of intramolecularly
coordinated sulfides.11
To add to our knowledge about intramolecularly coordinated
organopnictogen sulfides, we report here the reactions of
intramolecularly coordinated organoantimony and organobis-
muth chlorides L1-3MCl2 (L1-3 ) 2,6-(ROCH2)2C6H3-, where
R ) Me (L1), t-Bu (L2), or mesityl (L3); M ) Sb (L1 (1), L2
(2), L3 (3)) or M ) Bi (L2 (4))) with Na2S · 9H2O, which yielded
corresponding sulfides [L1-3MS]2, where M ) Sb (L1 (5), L2
(6), L3 (7)) or M ) Bi (L2 (8)) (Chart 1). The structures of all
compounds were studied by 1H and 13C NMR spectroscopy and
X-ray diffraction techniques. Investigation on the reactions of
the organoantimony sulfides 5-7 with iodine is also included.
L1SbX2
L2SbX2
L3SbX2
L4SbX2
(Sb-O)
(Sb-O)
(Sb-O)
(Sb-N)
X ) F
X ) Cl
X ) I
2.597(2)
2.606(2)
2.523(2)
2.577(2)
2.293(2)
2.279(2)
2.640(2)
2.678(2)
2.6294(14)
2.691(13)
2.302(2)
2.343(2)
a
a
2.560(3)
2.588(3)
2.491(9)
2.422(8)
a
2.818(4)
2.544(4)
2.620(2)
5.004(2)
a
a Not determined by X-ray diffraction.
although one of these interactions is significantly stronger,
Sb1-O1 ) 2.554(4) Å and Sb1-O2 ) 2.818(4) Å (∑cov(Sb,O)
) 2.14 Å, ∑vdW(Sb,O) ) 3.78 Å).12 This is in contrast to
antimony dichlorides3b 1 and 2 containing L1,2, where both
Sb-O intramolecular interactions are nearly equivalent (Table
1), approaching the shorter Sb-O distance detected in 3. This
most probably reflects increasing steric demand of L3 in 3. Both
oxygen atoms are placed mutually in cis fashion, O1-Sb1-O2
) 119.40(11)°, in 3. The overall geometry around the central
atom can be described in three alternative ways as a strongly
distorted tetragonal pyramid, ψ-octahedron, or bicapped trigonal
pyramid as previously discussed in detail for other O,C,O-
chelated halides.3b There are no significant intermolecular
contacts in the crystal structure of 3.
The reactions of starting chlorides 1-4 with Na2S · 9H2O in
toluene/water gave the expected organoantimony and organo-
bismuth sulfides [L1-3MS]2 (5-8) in moderate yield (Scheme
2). All compounds were isolated as slightly yellow powders,
which are soluble in chlorinated and aromatic solvents, but
nearly insoluble in aliphatic hydrocarbons. The proposed dimeric
nature of 5-8 was confirmed by mass spectra, where the
molecular adducts with alkali-metal ions, such as sodium,
[M + Na]+, and potassium, [M + K]+, were detected in all
cases.
Results and Discussion
Synthesis. Organoantimony chloride L3SbCl2 (3) containing
the novel bulky O,C,O pincer-type ligand L3 was prepared
(Scheme 1, Chart 1) with the aim to stabilize monomeric sulfide
(vide infra). Compound 3 was isolated as a colorless air-stable
crystalline solid.
The solid-state structure of 3 was determined by X-ray
diffraction. The unit cell contains two independent molecules
(atropoisomeric pair), and only the selected one is depicted in
Figure 1 and is described here in detail. Both donor oxygen
atoms are coordinated to the central antimony atom Sb1,
(9) (a) Sasamori, T.; Mieda, E.; Takeda, N.; Tokitoh, N. Chem. Lett.
2004, 33, 104. (b) Tokitoh, N.; Arai, Y.; Harada, J.; Okazaki, R. Chem.
Lett. 1995, 10, 959. (c) Sasamori, T.; Tokitoh, N. Dalton Trans. 2008, 1395.
(d) Sasamori, T.; Mieda, E.; Tokitoh, N. Bull. Chem. Soc. Jpn. 2007, 80,
2425.
(10) Opris, L. M.; Silvestru, A.; Silvestru, C.; Breunig, H. J.; Lork, E.
Dalton Trans. 2004, 3575.
Organoantimony sulfides 5-7 are stable at room temperature
both in solution and in the solid state for a long time (even
when heated to 50 °C for one week, no significant decomposi-
tion was observed by 1H NMR spectroscopy). In contrast,
(11) (a) Breunig, H. J.; Bala´zs, L.; Phillipp, N.; Soran, A.; Silvestru, C.
Phosphorus, Sulfur Silicon Relat. Elem. 2004, 179, 853. (b) Breunig, H. J.;
Koenigsmann, L.; Lork, E.; Nema, M.; Phillipp, N.; Silvestru, C.; Soran,
A.; Varga, R. A.; Wagner, R. Dalton Trans. 2008, 1831.
(12) Spek, A. L. PLATON, A Multipurpose Crystallographic Tool;
Utrecht University: Utrecht, The Netherlands, 2005; available at http://
www.cryst.chem.uu.nl/platon/.

1936 Organometallics, Vol. 28, No. 6, 2009
ChoVancoVa´ et al.
Scheme 2. Preparation of Studied Sulfides 5-8
formed by ispo-carbon C1 of the ligand and both sulfur atoms
(sum of angles of SbCS2 girdle, 290.9° for 5 and 283.6° for 7).
Although some molecular structures of dimeric monoorga-
noantimony sulfides [RSbS]2 have been determined,10 to the
best of our knowledge, all of them can be described as trans
type with the substituent R located mutually on the opposite
sides of the central ring. The cis position was in some
compounds caused by coordination of the antimony or the sulfur
atom to a transition metal.10,13 The molecular structure of cis-6
is depicted in Figure 3 and represents the first example of a
“free” cis isomer of monorganoantimony sulfide characterized
by X-ray diffraction in the solid state. The cis position of both
ligands L2 in 6 resulted in significant puckering of the central
Sb2S2 ring (see Figure 3). This is in direct contrast to the planar
central core detected in 5 and 7. The bond distances Sb-S
within the central ring are again nearly identical, Sb1-S1 )
2.460(3) Å and Sb1-S1b ) 2.463(3) Å, as are the bonding
angles, Sb1-S1-Sb1b ) 91.30(10)°, S1-Sb1-S1b ) 84.89(9)°.
As a result of weak coordination of both oxygen donor atoms
(Sb1-O1 ) 2.792(8) Å and Sb1-O2 ) 2.775(8) Å), the
coordination polyhedron around each antimony atom is a
bicapped trigonal pyramid similar to those in 5 and 7.
Table 2. Selected Bond Lengths (Å) and Angles (deg) of Compounds
5-8
5 (M ) Sb) 6 (M ) Sb) 7 (M ) Sb)
8 (M ) Bi)a
M1-S1
M1-S1a
M1-C1
M1-O1
M1-O2
2.4666(7)
2.4834(7)
2.169(3)
2.8362(18) 2.792(8)
2.6323(17) 2.775(8)
2.460(3)
2.463(3)
2.179(10) 2.178(4)
2.4536(12) 2.560(3) 2.549(3)
2.4619(12) 2.555(3) 2.547(3)
2.269(10) 2.268(10)
2.825(6) 2.777(7)
2.809(7) 2.815(7)
2.717(3)
2.894(3)
S1-M1-S1a 85.75(2)
M1-S1-M1a 94.26(2)
O1-M1-O2 116.20(5)
C1-M1-S1 96.62(6)
C1-M1-S1a 99.97(6)
84.89(9)
91.30(10) 93.78(2)
114.7(2)
97.6(3)
98.3(2)
86.22(4)
86.17(10) 85.81(10)
93.83(11) 94.19(11)
118.58(8) 113.44(19) 115.5(2)
98.31(12) 96.5(2)
99.08(12) 99.6(2)
98.6(3)
98.3(3)
a Two independent molecules in the unit cell.
In the case of compound 8, the unit cell contains two
independent molecules, but both differ only marginally in the
structural parameters (Table 2), so only the selected one is
depicted in Figure 4 and is described here in detail. The
molecular structure of organobismuth sulfide trans-8 is analo-
gous to those of previously published compounds containing
N,C,N-chelating ligand [2,6-(Me2NCH2)2C6H3BiS]2.11 Com-
pound 8 has a centrosymmetric dimeric structure with a Bi2S2
core (Bi1-S1 ) 2.560(3) Å and Bi1-Sb1a ) 2.555(3) Å), in
which both ligands are located in trans positions. Both donor
atoms are weakly coordinated to the central metal (Bi1-O1 )
2.825(6) Å and Bi1-O2 ) 2.809(7) Å, ∑vdW(Bi,O) ) 3.86 Å)12
in cis fashion (O1-Bi1-O2 ) 113.44(19)°), leading to the
bicapped trigonal pyramidal environment around each bismuth
atom analogously to sulfides 5-7.
organobismuth sulfide 8 is stable for weeks in solution and in
the solid state only below -30 °C. However, when kept at room
temperature for a longer time in chloroform solution, gradual
decomposition (within a few days) occurred and a completely
insoluble brown-black precipitate formed. Similar decomposition
had also been detected in the case of other organobismuth
sulfides.7c
Structure of Studied Sulfides. The molecular structures of
all sulfides 5-8 were determined in the solid state using the
single-crystal X-ray diffraction technique. Selected structural
parameters are collected in Table 2, and for crystallographic
data see Table 3. The single crystals were always grown from
solution containing both possible (cis, trans) isomers, but in all
cases in the crystal structures only one of these isomers was
present (trans for 5, 7, and 8 and cis for 6). Moreover, when
collected single crystals are dissolved, both isomers are present
The dimeric structure of sulfides 5-8 is retained in CDCl3
1
1
solution as shown by H and 13C NMR spectroscopy. The H
and 13C NMR spectra contained two sets of signals in the case
of all compounds 5-8 in CDCl3 at room temperature. The
1
in CDCl3 solution in a molar ratio (based on H NMR) almost
presence of two sets of signals in H and 13C NMR spectra of
1
identical to that detected after isolation of products from the
reaction mixtures, indicating fast formation of both isomers upon
dissolution.
organoantimony sulfides bearing a similar N,C-chelating ligand
was attributed to the formation of two possible isomersscis
and trans with respect to the position of the ligands on the
central Sb2S2 ring.10 Both isomers are present in 0.05 M CDCl3
solutions of 5-8 in approximately 1:0.85 (5, 6), 1:0.59 (7), and
1:0.56 (8) molar ratios based on the integration of the signal of
The molecular structure of organoantimony sulfides trans-5
and trans-7 are depicted together in Figure 2. Both structures
are very similar. Both compounds are centrosymmetric dimers
with a planar central Sb2S2 ring, and both ligands L are located
in trans positions. The Sb1-S1 and Sb1-S1a bond distances
are nearly identical within the central core, 2.4666(7) and
2.4834(7) Å for 5, 2.4536(12) and 2.4619(12) Å for 7. These
values are comparable to the Sb-S bond distances observed
for the N,C-chelated analogue [2-(Me2NCH2)C6H4SbS]2, al-
though in this case both Sb-S bond lengths are a bit more
distinct, 2.5338(12) vs 2.4245(12) Å.10 The angles S1-Sb1-S1a
are more acute in comparison to Sb1-S1-Sb1a in both cases
(85.75(2)° and 94.26(2)° for 5 and 86.22(4)° and 93.78(2)° for
7). The oxygen donor atoms O1 and O2 are coordinated to the
central atom through weak intramolecular interactions (2.6323(17)
and 2.8362(18) Å for 5, 2.717(3) and 2.894(3) Å for 7) mutually
in cis fashion (O1-Sb1-O2 ) 116.20(5)° for 5 and 118.58(8)°
for 7). The coordination polyhedron of the central antimony
atom can be described as a bicapped trigonal pyramid which is
1
the OCH2 groups in the H NMR spectra (see the Supporting
Information). Although the resonances of the OCH2 groups
could not be definitely assigned to each isomer, most probably
the trans isomer is the preferred one for steric reasons. It is
evident that even in the case of sterically crowded sulfide 7
both isomers are formed in solution, although their ratio of
1:0.59 under the same conditions points to an increased
preference for the trans isomer.
Reactions of Organoantimony Sulfides 5-7 with I2.
Recently, we have shown that the reaction of intramolecularly
coordinated organotin(IV) sulfides with I2 gives the correspond-
ing organotin iodides with concomitant elimination of elemental
(13) Breunig, H. J.; Ghesner, I.; Lork, E. Appl. Organomet. Chem. 2002,
16, 547.

Organoantimony and Organobismuth Sulfides
Organometallics, Vol. 28, No. 6, 2009 1937
Table 3. Crystallographic Data for 3, 5-8, 10, and 12
3
5
6
7
8
10
12
empirical formula
cryst syst
space group
a(Å)
b(Å)
c(Å)
C26H28Cl2O2Sb C20H26O4S2Sb2 C34H54Cl4O4S2Sb2 C56H66O5S2Sb2 C32H50Bi2ClO4S2 C26H29I2O2Sb
C24H32I2O4Sb2
monoclinic
C2/c
23.1689(11)
10.7841(9)
24.7928(12)
90
115.407(13)
90
8
monoclinic
P21
monoclinic
P21/n
monoclinic
C2/c
monoclinic
P21/c
triclinic
P1
triclinic
P1
j
j
11.8007(3)
17.1360(12)
12.3284(11)
90
102.596(5)
90
9.3281(2)
7.2572(2)
17.1797(4)
90
99.6414(14)
90
19.6912(9)
8.8823(12)
27.4682(13)
90
109.581(13)
90
15.8025(14)
13.7531(16)
13.8521(18)
90
108.412(8)
90
10.6653(8)
10.8035(10)
19.7842(19)
102.245(8)
92.040(8)
96.605(7)
2
8.1363(2)
10.7204(8)
15.9477(8)
82.391(6)
77.112(3)
79.080(6)
2
R (deg)
ꢀ (deg)
γ (deg)
Z
4
2
4
2
µ (mm-1
)
1.374
2.561
1.553
1.061
8.138
3.389
4.164
2.093
Dx (Mg m-3
)
1.543
1.848
1.433
1.310
1.528
1.877
cryst size (mm)
0.31 × 0.21 × 0.25 × 0.15 × 0.36 × 0.24 ×
0.47 × 0.26 × 0.36 × 0.19 ×
0.75 × 0.43 × 0.28 × 0.13 ×
0.15
0.08
0.15
0.11
0.06
0.16
0.11
θ range (deg)
1-27.5
0.554, 0.778
19804
1-27.5
0.679, 0.870
16 501
1-27.5
0.656, 0.785
41 237
1-27.5
0.782, 0.917
26 422
1-27.5
0.084, 0.648
40 961
1-27.5
0.119, 0.592
24 250
1-27.5
0.503, 0.719
41 882
Tmin, Tmax
no. of reflns measd
no. of unique reflns,
10097, 0.036
2641, 0.036
4918, 0.045
6536, 0.049
10119, 0.078
6019, 0.084
6396, 0.044
a
Rint
no. of obsd reflns
[I > 2σ(I)]
9927
559
2311
130
4114
222
4962
316
7303
433
5624
280
5044
289
no. of params
b
w1/w2
0.0799/2.9367 0.0135/1.3119 0.0236/195.0838
1.055
0.041
0.0526/5.0147 0.0555/24.8677
1.094
0.044
0.1127/3.9669 0.0797/168.2457
1.108
0.065
S,c all data
1.12
0.022
1.298
0.087
1.061
0.059
1.070
0.059
final Rd indices
[I > 2σ(I)]
wR2d indices (all data) 0.109
0.049
0.205
0.123
0.153
0.177
0.177
∆F (max, min) (e Å-3
)
0.672, -1.188 1.051, -0.569 2.871, -2.469
1.087, -0.688 3.169, -2.288
3.226, -4.876 2.454, <23.2.821
a
b
c
2
2
2
2
2
Rint ) ∑|Fo - Fo,mean2|/∑Fo . Weighting scheme: w ) [σ2(Fo ) + (w1P)2 + w2P]-1, where P ) [max(Fo ) + 2Fc2]. S ) [∑(w(Fo - Fc2)2)/
d
2
2
(Ndiffrs - Nparams)]1/2
. .
R(F) ) ∑||Fo| - |Fc||/∑|Fo|, wR(F2) ) [∑(w(Fo - Fc2)2)/(∑w(Fo )2)]1/2
Figure 2. ORTEP drawings (50% probability atomic displacement ellipsoids) of trans-5 (left) (symmetry code a: -x, -y, -z) and trans-7
(right) (symmetry code a: -x, -y + 1, 1 - z). Hydrogen atoms and the THF molecule (in trans-7) have been omitted for clarity.
sulfur.14 The organoantimony sulfides 5-7 follow a similar
reaction path, as shown by the reactions of 5-7 with 2 equiv
of I2. These reactions of 5 and 7, as expected, gave intramo-
lecularly coordinated diiodides L1,3SbI2 (L1 (9) and L3 (10)) in
moderate yield. Compound 9 had been prepared previously and
characterized by electrospray ionization (ESI) mass spectrometry
second donor group remains pendant (Sb1-O2 ) 5.006(4) Å).
The overall geometry around the central antimony atom can be
described as an equatorially vacant trigonal bipyramid. The axial
positions are occupied by the oxygen donor atom O1 and I2
atom (O1-Sb1-I2 ) 167.22(10)°), and the ipso-carbon C1 and
the second iodine I1 are located in the equatorial positions.
Closer inspection of the molecular structure of 10 revealed short
1
and H and 13C NMR spectroscopy. All data of 9 are in good
agreement with those reproted.3b The identity of compound 10
was established by elemental analysis, ESI mass spectrometry,
and 1H and 13C NMR spectroscopy. The molecular structure of
10 was determined by the single-crystal X-ray diffraction
technique (Figure 5). Only one of the donor oxygen atoms, O1,
is coordinated to the central Sb atom by a medium strong
intramolecular interaction (Sb1-O1 ) 2.622(4) Å), while the
intermolecular contacts Sb1-I2 · · · Sb1a (3.8342(6) Å, ∑vd
-
W(Sb,I) ) 4.24 Å),12 leading to a formation of weakly bound
dimeric entities. Similar weak intermolecular contacts were
observed in analogous O,C,O-chelated iodides.3b
Of particular interest is a weakening of the dative Sb-O
intramolecular interaction on going from chloride 3 to iodide
10 (Table 1). In all other organoantimony halides containing
ligands L1,2 or N,C,N analogue L4 [2,6-(Me2NCH2)2C6H3]-,
using heavier halogens resulted in reinforcement of the present
(14) Dosta´l, L.; Jambor, R.; Ru˚zˇicˇka, A.; Jira´sko, R.; Taraba, J.; Holecˇek,
J. J. Organomet. Chem. 2007, 692, 3750.

1938 Organometallics, Vol. 28, No. 6, 2009
ChoVancoVa´ et al.
Figure 3. ORTEP drawings (50% probability atomic displacement
ellipsoids) of cis-6 (symmetry code b: 1 - x, -y, 1/2 - z) and
view on the puckered central Sb2S2 ring. Hydrogen atoms and the
CH2Cl2 molecule have been omitted for clarity.
Figure 5. ORTEP drawings (50% probability atomic displacement
ellipsoids) of 10 (symmetry code a: -x, -y, -z). Hydrogen atoms
have been omitted for clarity. Selected bond distances (Å): Sb1-O1,
2.622(4); Sb1-O2, 5.006(4); Sb1-I1, 2.7491(5); Sb1-I2, 2.8056(6);
Sb1-C1, 2.177(6). Selected bond angles (deg): O1-Sb1-I2,
167.22(10);I1-Sb1-I2,99.83(2);O3-Sb1-I1,92.50(10);C1-Sb1-O3,
72.65(18); C1-Sb1-I1, 95.27(16); C1-Sb1-I2, 102.63(15).
Scheme 3. Reaction of Compound 6 with I2
of organophosphorus analogues17 and also in the reaction of 2
Figure 4. ORTEP drawings (50% probability atomic displacement
ellipsoids, one of two independent molecules in the unit cell) of
trans-8 (symmetry code a: -x + 1, -y + 2, -z + 1). Hydrogen
atoms and the CHCl3 molecule have been omitted for clarity.
5
-
with the silver salt of triflate or CB11H12 cluster anions. The
identity of compound 12 was established by elemental analysis
and 1H and 13C NMR spectroscopy. 1H NMR spectra contained
two signals for OCH2 groups (2:2 integral ratio), a broad signal
at 5.59 ppm belonging to OCH2 within the C3SbO ring and a
sharp one at 4.75 ppm appropriate for OCH2 of the second ligand
arm. There was only one signal detected in the region of t-Bu
moieties at 1.47 ppm with an integral value of 9, clearly
demonstrating that only one of the t-Bu groups is present in
12. Also in the aromatic region of the 1H NMR spectrum three
signals were observed in a 1:1:1 ratio, indicating nonequivalence
of three aromatic protons, which is in accordance with the pro-
posed structure. Five resonances were observed in the aromatic
region in the 13C NMR spectrum (the signal of the ipso-carbon
was not detected), and two signals for OCH2 emerged; these
findings confirm the proposed structure. Compounds containing
a similar ligand system (the so-called Martin ligand) have been
Sb-O(N) dative bonds. This tendency is especially evident
between Cl and I congeners (Table 1).3,4
The reaction of 6 with 2 equiv of iodine yielded the expected
diiodide L2MI2 (11) as the major product. This compound was
characterized in the reaction mixture by ESI mass spectrometry
3b
1
and H and 13C NMR spectroscopy. However, an unprec-
edented organoantimony compound, 12, was obtained as the
minor product in this reaction (Scheme 3). Compound 12 could
be isolated in very low yield (∼10%) by repeated extraction of
the reaction mixture with a 1:3 toluene/hexane mixture. Forma-
tion of oxastibol 12 can be explained as an intramolecular ether
bond cleavage, leading to the cyclization of one of the ligand
arms to a C3SbO ring.15,16 Similar reactions occur in the case
(15) It is highly probable that compound 12 is formed by t-BuI
elimination from 11 during the reaction. Similar fragmentation has been
recently obtained in mass spectra of 11 (see ref 3b) and analogous
organotin(IV) compounds (see ref 16). The mechanism of this type of
reaction is currently being investigated in our laboratories. We thank one
of the reviewers of this manuscript for suggestions concerning this
phenomenon.
(16) Kola´rˇova´, L.; Holcˇapek, M.; Jambor, R.; Dostál, L.; Na´dvornı´k,
M.; Ru˚zˇicˇka, A. J. Mass Spectrom. 2004, 39, 621.
(17) (a) Yoshifuji, M.; Makazawa, N.; Sato, T.; Toyota, K. Tetrahedron
2000, 56, 43. (b) Toyota, K.; Kawasaki, S.; Yoshifuji, M. Tetrahedron Lett.
2002, 43, 7953.

Organoantimony and Organobismuth Sulfides
Organometallics, Vol. 28, No. 6, 2009 1939
Å), and the oxygen atom O3 is again located in a trigonal planar
environment (the sum of the angles of the girdle around O5 is
359.6°). The central eight-membered Sb4O4 ring is strongly
puckered (Figure 6), where two nearly planar Sb2O2 moieties
are joined through weak Sb1(a)-O3(a) interactions. The iodine
atoms are coordinated to the central antimony atoms through
regular covalent bonds (Sb1-I1 ) 2.7889(12) Å, Sb2-I2 )
2.8065(11) Å). The coordination geometry around each anti-
mony atom (for example, Sb1) taking into account all coordi-
nated oxygen atoms (for Sb1, i.e., O1, O2, and O3a) can be
described as a distorted tetragonal pyramid, with the ipso-carbon
atom C1 located in the apical position and O1, O2, O3a, and I1
atoms forming the basal plane, where atoms I1, O3a (175.58(16)
Å) and O1, O2 (148.4(2) Å) are mutually placed in trans
positions. The structure of a similar oxastibol has been recently
described as well.19 In this case the endocyclic oxygen atom is
involved in OH · · · O hydrogen bonding.
Experimental Section
General Remarks. 1H and 13C NMR spectra were recorded on
Bruker AMX360 and Bruker500 Avance spectrometers, respec-
tively, using 5 mm tunable broad-band probes. Appropriate chemical
Figure 6. ORTEP drawings (40% probability atomic displacement
ellipsoids) of 12 (symmetry code a: -x + 1, y, -z + 1/2). Hydrogen
atoms have been omitted for clarity. Selected bond distances (Å):
Sb1-C1, 2.109(9); Sb1-O1, 2.029(7); Sb1-O2, 2.703(7); Sb1-I1,
2.7889(12); O1-Sb2, 2.468(7); Sb2-C13, 2.103(9); Sb2-O3,
2.037(7); Sb2-O4, 2.662(7); Sb2-I2, 2.8065(11); Sb1-O3a,
2.565(7). Selected bond angles (deg): C1-Sb1-O1, 80.6(3);
O1-Sb1-O2, 148.4(2); I1-Sb1-O3a, 175.58(16); Sb1-O1-Sb2,
129.3(3);C13-Sb2-O3,81.3(3);O3-Sb2-O4,148.7(3);I2-Sb2-O1,
174.48(16); Sb2-O3-Sb1a, 135.0(3).
1
shifts in H and 13C NMR spectra were calibrated on the residual
signals of the solvent (CDCl3, δ(1H) ) 7.27 ppm and δ(13C) )
77.23 ppm) or external Me4Si (δ(1H) ) 0.0 ppm). In the case of
organometallic sulfides 5-8 the integral values are not given in
1H NMR data, because they coexist as two (cis, trans) isomers,
and so the full description may be a bit confusing.
Positive-ion ESI mass spectra were measured on an ion trap
analyzer, Esquire 3000 (Bruker Daltonics, Bremen, Germany), in
the range m/z 50-1500. The samples were dissolved in acetonitrile
and analyzed by direct infusion at a flow rate of 5 µL/min. The
selected precursor ions were further analyzed by MS/MS analyses
under the following conditions: isolation width m/z ) 6, collision
amplitude in the range 0.8-1.0 V depending on the precursor ion
stability, ion source temperature 300 °C, tuning parameter com-
pound stability 100%, flow rate and pressure of nitrogen 4 L/min
and 10 psi, respectively. All masses listed in this section are related
to the 121Sb configuration.
Air- and moisture-sensitive operations were carried out under
an argon atmosphere using the standard Schlenk technique, and
solvents were purified by standard procedures. Na2S · 9H2O and a
1.6 M solution of n-BuLi in hexane were obtained from commercial
suppliers and used as delivered. Starting compounds 1, 2, and 4
were prepared according to published procedures.3b
X-ray Structure Determination. Suitable single crystals of 3,
5-8, 10, and 12 were mounted on a glass fiber with an oil and
measured on a four-circle diffractometer, KappaCCD, with a CCD
area detector by monochromatized Mo KR radiation (λ ) 0.71073
Å) at 150(1) K (Table 3). The numerical20 absorption corrections
from the crystal shape were applied for all crystals, and multiscan21
was applied for 7. The structures were solved by the direct method
(SIR9222) and refined by a full matrix least-squares procedure based
on F2 (SHELXL9723). Hydrogen atoms were fixed into idealized
positions (riding model) and assigned temperature factors Hiso(H)
) 1.2Ueq(pivot atom); for the methyl moiety a multiple of 1.5 was
chosen. The final difference maps displayed no peaks of chemical
extensively studied with both pentavalent and trivalent central
antimony atoms.18
Finally, the molecular structure of 12 was established by
single-crystal X-ray analysis (Table 3, Figure 6). In 12 one of
the ligand arms was disrupted with formation of an Sb-O
covalent bond, while the second one remained intact, proving
the proposed structure in solution (vide supra and Figure 6).
The bond distances Sb1-O1 ) 2.029(7) Å and Sb2-O3 )
2.037(7) Å are comparable with ∑cov(Sb,O) ) 2.14 Å12
indicating the presence of a covalent bond and formation of
five-membered C3SbO rings. These rings are not perfectly
planar, but the methylene groups are a bit bent out. The other
oxygen donor atoms O2 and O4 remain coordinated to the
central antimony atoms through medium strong intramolecular
interactions (Sb1-O2 ) 2.703(7) Å and Sb2-O4 ) 2.662(7)
Å). One of the endocyclic oxygen atoms, O1, is involved in an
intermolecular contact with the adjacent molecule, forming a
dimeric unit. The Sb2-O1 ) 2.468(7) Å bond length indicates
strong intermolecular connection between both moieties. The
geometry around O1 can be described as a nearly ideal trigonal
planar environment (the sum of the angles of the girdle around
O1 is 360.1°). In turn, the second endocyclic oxygen, O3, is
joined with another molecule of an analogous dimer, forming
the final centrosymmetric tetrameric structure of 12. This
connection, Sb1a-O3 ) 2.565(7) Å, is significantly longer than
intermolecular contacts within each dimer (Sb2-O1 ) 2.468(7)
(19) Sharma, P. A.; Pe´rez, D.; Rosa, N.; Cabrera, A.; Toscano, A. J.
Organomet. Chem. 2006, 691, 579.
(20) Coppens, P. In Crystallographic Computing; Ahmed, F. R., Hall,
S. R., Huber, C. P., Eds.; Munksgaard: Copenhagen, 1970; pp 255-270.
(21) Blessing, R. H. J. Appl. Crystallogr. 1997, 30, 421.
(22) Altomare, A.; Cascarone, G.; Giacovazzo, C.; Guagliardi, A.; Burla,
M. C.; Polidori, G.; Camalli, M. J. Appl. Crystallogr. 1994, 27, 1045.
(23) Sheldrick, G. M. SHELXL-97, A Program for Crystal Structure
Refinement; University of Go¨ttingen: Go¨ttingen, Germany, 1997.
(18) For example see: (a) Yamamoto, Y.; Okazaki, M.; Wakisaka, Y.;
Akiba, K. Organometallics 1995, 14, 3364. (b) Akiba, K.; Fujikawa, H.;
Sunaguchi, Y.; Yamamoto, Y. J. Am. Chem. Soc. 1987, 109, 1245. (c) Akiba,
K.; Nakata, H.; Yamamoto, Y.; Kojima, S. Chem. Lett. 1992, 30, 1559. (d)
Uchiyama, Y.; Kano, N.; Kawashima, T. J. Org. Chem. 2006, 71, 659. (e)
Wakisaka, Y.; Yamamoto, Y.; Akiba, K. Heteroat. Chem. 2001, 12, 33. (f)
Yamamoto, Y.; Chen, X.; Kojima, S.; Ohdoi, K.; Kitano, M.; Doi, Y.; Akiba,
K. J. Am. Chem. Soc. 1995, 117, 3922.

1940 Organometallics, Vol. 28, No. 6, 2009
ChoVancoVa´ et al.
1
significance as the highest peaks and holes are in close vicinity
(∼1 Å) of heavy atoms, except in compound 8, where they are
located between the chlorine atoms of a disordered solvate molecule
(chloroform).
K]+; m/z 827 [M + Na]+, 100. H NMR (500 MHz, CDCl3): δ
1.27, overlap of two signals ((CH3)3CO), 4.72 and 4.92 (s, OCH2),
6.75 and 7.12 (d, Ar-H3,5), 6.83 and 7.19 (t, Ar-H4). 13C NMR
(125.76 MHz, CDCl3): δ 27.7, overlap of two signals ((CH3)3CO),
65.3 and 65.4 (s, OCH2), 75.7 and 75.8 (s, (CH3)3CO), 124.9 and
125.6 (s, Ar-C3,5), 127.1 and 127.4 (s, Ar-C4), 146.0 and 147.1
(s, Ar-C2,6), 145.3 and 148.3 (s, Ar-C1).
Synthesis of 1,3-(2′,4′,6′-(CH3)3C6H2OCH2)2C6H4 (L3). 1,3-
(CH2Br)2C6H4 (12.4 g, 0.047 mol) in THF (100 mL) was added to
2,4,6-(CH3)3C6H2O-Na+ (14.8 g, 0.093 mol) in THF (300 mL) and
the resulting mixture stirred overnight. NaBr was filtered, and the
filtrate was evaporated in vacuo to dryness, providing a yellow oil,
which was dissolved in hexane (50 mL). Colorless crystals were
obtained after crystallization at -30 °C, collected by filtration, and
dried in vacuo. Yield: 13.7 g (78%). Mp: 79-81 °C. Anal. Calcd
for C26H30O2 (MW 374.53): C, 83.4; H, 8.1. Found: C, 83.5; H,
8.2. 1H NMR (500 MHz, CDCl3): δ 2.30 (6H, s,p-CH3-Mes), 2.32
(12H, s, o-CH3-Mes), 4.86 (4H, s, OCH2), 6.89 (4H, s, m-H-Mes),
7.48 (3H, m, Ar-H3,4,5), 7.65 (1H, s, Ar-H1). 13C NMR (125.76
MHz, CDCl3): δ 16.5 (s, o-CH3-Mes), 20.9 (s, p-CH3-Mes), 74.1
(s, OCH2), 127.1 (s, Ar-C1), 127.4 (s, Ar-C3,5), 128.9 (s, Ar-C4),
129.7 (s, m-C-Mes), 130.9 (s, o-C-Mes), 133.5 (s, p-C-Mes), 138.4
(s, Ar-C2,6), 153.7 (s, C-O-Mes).
Synthesis of [2,6-(2′,4′,6′-(CH3)3C6H2OCH2)2C6H3SbS]2 (7).
Compound 7 was prepared analogously to 5 using 3 (345 mg, 0.61
mmol) and Na2S · 9H2O (150 mg, 0.62 mmol). Yield: 0.17 g (52%).
Mp: 199-202 °C. Anal. Calcd for C52H58O4S2Sb2 (MW 1054.67):
C, 59.2; H, 5.5. Found: C, 59.0; H, 5.8. Positive-ion MS: m/z 1091
[M + K]+, 100; m/z 1075 [M + Na]+; m/z 565 [LSbS + K]+; m/z
549 [LSbS + Na]+. 1H NMR (500 MHz, CDCl3): δ 2.14 and 2.16
(s, p-CH3-Mes), 2.17 and 2.25 (s, o-CH3-Mes), 5.39 and 5.56 (4H,
s, OCH2), 6.80, overlap of two signals (m-H-Mes), 6.85 and 7.15
(d, Ar-H3,5), 6.90 and 7.26 (t, Ar-H4). 13C NMR (125.76 MHz,
CDCl3): δ 17.3 and 17.6 (s, p-CH3-Mes), 17.6 and 20.8 (s, o-CH3-
Mes), 77.0 and 77.1 (s, OCH2), 125.0 and 125.7 (s, Ar-C3,5), 127.6
and 127.9 (s, Ar-C4), 129.5, overlap of two signals (m-C-Mes),
131.0 and 131.1 (s, o-C-Mes), 133.7, overlap of two signals (s,
p-C-Mes), 145.5 and 146.4 (s, Ar-C2,6), 146.6 and 148.9 (s, Ar-
C1), 155.2 and 155.4 (s, C-O-Mes).
Synthesis of 2,6-(2′,4′,6′-(CH3)3C6H2OCH2)2C6H3SbCl2 (3).
n-BuLi (3.5 mL, 1.6 M solution in hexane, 5.6 mmol) was added
to a solution of L3 (2.07 g, 5.5mmol) in hexane (20 mL) and the
resulting mixture stirred for an additional 24 h. During this time a
white suspension of L3Li formed and was collected by filtration,
washed by a minimum amount of hexane (5 mL) and dried in vacuo,
giving 1.47 g of L3Li. The lithium salt was dissolved in Et2O (30
mL) and added to a cooled (-70 °C) solution of SbCl3 (0.88 g, 3.9
mmol) in Et2O (50 mL); then the reaction mixture was allowed to
reach room temperature and stirred for an additional 12 h. The
solvent was evaporated in vacuo, and the resulting oily product
was extracted by 2 × 30 mL of CH2Cl2. Insoluble material was
filtered, the filtrate was evaporated, and the crude product was
crystallized from a hexane/CH2Cl2 mixture. Yield: 1.27 g (58%).
Mp: 181-184 °C. Anal. Calcd for C26H29O2Cl2Sb (MW 566.18):
C, 55.2; H, 5.2. Found: C, 55.5; H, 5.0. Positive-ion MS: m/z 1039
[LSbOSbLCl]+; m/z 529 [M - Cl]+; m/z 511 [LSbOH]+, 100; m/z
493 [M - Cl - HCl]+. Negative-ion MS: m/z 599 [M + Cl]-,
Synthesis of [2,6-(t-BuOCH2)2C6H3BiS]2 (8). Compound 8 was
prepared analogously to 5, with the exception that the reaction
mixture was stirred only for 2 h, and during evaporation of toluene
this solution must not be heated (use a vacuum); otherwise
decomposition of the product is observed (see the Results and
Discussion). Also the purity of starting 4 should be guaranteed,
because only a small amount of bismuth chloride remaining from
the preparation of 4 can hamper the whole synthesis. A 300 mg
(0.6 mmol) portion of 4 and a 145 mg (0.6 mmol) portion of
Na2S · 9H2O were used. Yield: 106 mg (38%). Mp: 148 °C dec.
Anal. Calcd for C32H50O4S2Bi2 (MW 980.84): C, 39.2; H, 5.1;
Found: C, 39.5; H, 4.9. Positive-ion MS: m/z 1019 [M + K]+; m/z
1003 [M + Na]+, 100; m/z 981 [M + H]+; m/z 529 [LBiS + K]+;
m/z 313 [LBiS + Na]+; m/z 491 [LBiSH]+. H NMR (500 MHz,
1
CDCl3): δ 1.25 and 1.27 (s, (CH3)3CO), 4.77 and 4.96 (s, OCH2),
6.88 and 7.26 (d, Ar-H3,5), 7.03 and 7.38 (t, Ar-H4). 13C NMR
(125.76 MHz, CDCl3): δ 27.8, overlap of two signals ((CH3)3CO),
67.5 and 67.6 (s, OCH2), 75.7, overlap of two signals ((CH3)3CO),
126.9 and 127.3 (s, Ar-C3,5), 128.0, overlap of two signals (Ar-
C4), 149.6 and 150.6 (s, Ar-C2,6), Ar-C1 not obtained.
Synthesis of 2,6-(MeOCH2)2C6H3SbI2 (9). A solution of I2 (200
mg, 0.8 mmol) in CH2Cl2 (10 mL) was added to a solution of 5
(250 mg, 0.4 mmol) in CH2Cl2 (30 mL). The resulting mixture was
stirred for 12 h and then evaporated in vacuo. The residue was
extracted with a minimum amount of chloroform. Filtration
followed by evaporation of the solvent gave 9 as a pale yellow
powder after washing with hexane. Yield: 208 mg (48%). Mp:
158-161 °C. Other analytical data correspond to those published
elsewhere.3b
1
100. H NMR (500 MHz, CDCl3): δ 2.24 (12H, s, o-CH3-Mes),
2.31 (6H, s, p-CH3-Mes), 5.52 (4H, s, OCH2), 6.88 (4H, s, m-H-
Mes), 7.31 (2H, d, Ar-H3,5), 7.41 (1H, t, Ar-H4). 13C NMR (125.76
MHz, CDCl3): δ 18.0 (s, o-CH3-Mes), 20.9 (s, p-CH3-Mes), 76.9
(s, OCH2), 125.3 (s, Ar-C3,5), 129.7 (s, Ar-C4), 129.8 (s, m-C-
Mes), 130.7 (s, o-C-Mes), 134.8 (s, p-C-Mes), 146.5 (s, Ar-C2,6),
151.5 (s, Ar-C1), 154.7 (s, C-O-Mes).
Synthesis of [2,6-(MeOCH2)2C6H3SbS]2 (5). Compound 1 (450
mg, 1.26 mmol) was dissolved in toluene (20 mL), added to a water
solution (20 mL) of Na2S · 9H2O (0.312 mg, 1.30 mmol), and stirred
for an additional 12 h. Then the toluene fraction was separated,
and the water layer was washed twice with toluene (10 mL).
Combined toluene fractions were dried over Na2SO4 and evaporated
in vacuo to dryness. The white material was washed with hexane
(2 × 5 mL), giving a slightly yellow powder of 5. Yield: 0.2 g
(51%). Mp: 153-156 °C. Anal. Calcd for C20H26O4S2Sb2 (MW
638.06): C, 37.7; H, 4.1. Found: C, 37.4; H, 4.4. Positive-ion MS:
m/z 675 [M + K]+; m/z 659 [M + Na]+, 100; m/z 357 [LSbS +
Synthesis of 2,6-(2′,4′,6′-(CH3)3C6H2OCH2)2C6H3SbI2 (10).
Compound 10 was prepared analogously to 9 using I2 (144 mg,
0.56 mmol) and 7 (300 mg, 0.28 mmol). Yield: 230 mg (55%).
Mp: 160-163 °C. Anal. Calcd for C26H29O2I2Sb (MW 749.08): C,
41.7; H, 3.9. Found: C, 41.4; H, 4.2. Positive-ion MS: m/z 621
[M - I]+; m/z 511 [LSbOH]+, 100. Negative-ion MS: m/z 875 [M
+ I]-; m/z 127 [I]-, 100. 1H NMR (500 MHz, CDCl3): δ 2.27 (12H,
s, o-CH3-Mes), 2.28 (6H, s, p-CH3-Mes), 5.43 (4H, s, OCH2), 6.86
1
K]+; m/z 341 [LSbS + Na]+. H NMR (CDCl3): δ 3.35 and 3.37
(s, CH3O), 4.48 and 5.04 (s, OCH2), 6.87 and 7.18 (d, Ar-H3,5),
6.97 and 7.27 (t, Ar-H4). 13C NMR (125.76 MHz, CDCl3): δ 58.5,
overlap of two signals (CH3O), 75.4 and 75.6 (s, OCH2), 125.6
and 126.3 (s, Ar-C3,5), 127.6 and 128.0 (s, Ar-C4), 144.9 and 145.7
(s, Ar-C2,6), Ar-C1 not obtained.
Synthesis of [2,6-(t-BuOCH2)2C6H3SbS]2 (6). Compound 6 was
prepared analogously to 5 using 2 (520 mg, 1.18 mmol) and
Na2S · 9H2O (290 mg, 1.2 mmol). Yield: 0.26 g (54%). Mp:
123-127 °C. Anal. Calcd for C32H50O4S2Sb2 (MW 806.38): C, 47.7;
H, 6.3. Found: C, 47.4; H, 6.0. Positive-ion MS: m/z 843 [M +
(4H, s, m-H-Mes), 7.50 (1H, t, Ar-H4), 7.61 (2H, d, Ar-H3,5). 13
C
NMR (125.76 MHz, CDCl3): δ 17.7 (s, o-CH3-Mes), 20.9 (s, p-CH3-
Mes), 76.8 (s, OCH2), 126.7 (s, Ar-C3,5), 129.7 (s, m-C-Mes), 130.7
(s, o-C-Mes), 130.9 (s, Ar-C4), 134.3 (s, p-C-Mes), 145.3 (s, Ar-
C2,6), 153.9 (s, C-O-Mes), Ar-C1 not obtained.
Reaction of [2,6-(t-BuOCH2)2C6H3SbS]2 and I2. A solution of
I2 (265 mg, 1.04 mmol) in CH2Cl2 (10 mL) was added to a solution

Organoantimony and Organobismuth Sulfides
Organometallics, Vol. 28, No. 6, 2009 1941
of 6 (420 mg, 0.52 mmol) in CH2Cl2 (30 mL). The resulting mixture
was stirred for 12 h and then evaporated in vacuo. 1H and 13C NMR
spectra revealed besides signals of the expected product 2,6-(t-
BuOCH2)2C6H3SbI2 (11) (analytical data correspond to those in the
literature3b) signals of novel compound 2-(OCH2)-6-(t-BuOCH2)-
C6H3SbI (12); see the Results and Discussion. Compound 12 was
isolated from this mixture as follows. The evaporated reaction
mixture was extracted twice with a mixture of toluene/hexane (1:
3), and evaporation of the solvents yielded a yellow powder, which
was washed with pentane and dried in vacuo. Yield: 55 mg (12%).
Mp: 108-110 °C. Anal. Calcd for C12H16O2ISb (MW 440.91): C,
32.7; H, 3.7. Found: C, 32.5; H, 3.9. Positive-ion MS: m/z 753
[2M - I]+, 100; m/z 331 [M - I + H2O]+; m/z 313 [M - I]+. 1H
NMR (500 MHz, CDCl3): δ 1.47 (9H, s, (CH3)3CO), 4.75 (2H, s,
(CH3)3COCH2), 5.59 (2H, s (br), SbOCH2), 7.17 (1H, d, Ar-H),
7.36 (1H, d, Ar-H), 7.39 (1H, dd, Ar-H). 13C NMR (125.76 MHz,
CDCl3): δ 28.4 (s, (CH3)3CO), 62.6 (s, (CH3)3COCH2), 77.2 (s,
SbOCH2), 77.9 (s, (CH3)3CO), 120.8, 123.3, 130.3 143.9, 153.5
(s, Ar-C), Ar-C1 not detected.
Acknowledgment. We thank the Grant Agency of the
Czech Republic (Grant 203/07P094) and The Ministry of
Education of the Czech Republic (Grants MSM0021627501
and LC523) for financial support. R.Ji. acknowledges the
support of Grant Project MSM0021627502 sponsored by The
Ministry of Education, Youth and Sports of the Czech
Republic.
1
Supporting Information Available: H NMR spectra of 5-7
and CIF data. This material is available free of charge via the
Internet at http://pubs.acs.org. Crystallographic data for structural
analysis have been deposited with the Cambridge Crystallographic
Data Centre, CCDC Nos. 670097 for 5 and 713304-713309 for
3, 6-8, 10, and 12. Copies of this information may be obtained
free of charge from The Director, CCDC, 12 Union Rd., Cambridge
CB2 1EY, U.K. (fax, +44-1223-336033; e-mail, deposit@ccdc.
cam.ac.uk; URL, http://www.ccdc.cam.ac.uk).
OM801194H