Synthesis and deborination of polyhalo-substituted ortho-carboranes

Article abstract of DOI:10.1134/S1070363211060107

Tetraiodo-1,2-dicarba-closo-dodecaborane and 9-bromo-8,10,12-triiodo-1,2- dicarba-closo-dodecaborane were synthesized by oxidative iodination of 1,2-dicarba-closo-dodecaborane and 9-bromo-1,2-dicarba-closododecaborane, respectively, in AcOH using a mixture of nitric and sulfuric acid as an oxidant of iodine. The intermediates in the ortho-carborane iodination were identified. By the action of elemental bromine on 9-iodo- 1,2-dicarba-closo-dodecaborane in the presence of aluminum chloride catalyst 9-iodo-8,10,12-tribromo-1,2- dicarba-closo-dodecaborane was obtained. Deborination of the synthesized substances with an alcohol solution of KOH led to formation of 1,5,6,10-tetraiodo-5-bromo-1,6,10-triiodo- and 5-iodo-1,6,10-tribromo-7,8- dicarbaundecaborates methylammonium salts. Pleiades Publishing, Ltd., 2011.

Full text of DOI:10.1134/S1070363211060107

ISSN 1070-3632, Russian Journal of General Chemistry, 2011, Vol. 81, No. 6, pp. 1137–1142. © Pleiades Publishing, Ltd., 2011.
Original Russian Text © D.A. Rudakov, P.V. Kurman, V.I. Potkin, 2011, published in Zhurnal Obshchei Khimii, 2011, Vol. 81, No. 6, pp. 943–948.
Synthesis and Deborination
of Polyhalo-Substituted ortho-Carboranes
D. A. Rudakov, P. V. Kurman, and V. I. Potkin
Institute of Physical Organic Chemistry, National Academy of Sciences of Belarus,
ul. Surganova 13, Minsk, 220072 Belarus
e-mail: potkin@ifoch.bas-net.by
Received April 3, 2010
Abstract—Tetraiodo-1,2-dicarba-closo-dodecaborane and 9-bromo-8,10,12-triiodo-1,2-dicarba-closo-dodecaborane
were synthesized by oxidative iodination of 1,2-dicarba-closo-dodecaborane and 9-bromo-1,2-dicarba-closo-
dodecaborane, respectively, in АсОН using a mixture of nitric and sulfuric acid as an oxidant of iodine. The
intermediates in the ortho-carborane iodination were identified. By the action of elemental bromine on 9-iodo-
1,2-dicarba-closo-dodecaborane in the presence of aluminum chloride catalyst 9-iodo-8,10,12-tribromo-1,2-
dicarba-closo-dodecaborane was obtained. Deborination of the synthesized substances with an alcohol solution
of KOH led to formation of 1,5,6,10-tetraiodo-5-bromo-1,6,10-triiodo- and 5-iodo-1,6,10-tribromo-7,8-
dicarbaundecaborates methylammonium salts.
DOI: 10.1134/S1070363211060107
Iodine derivatives of carboranes are valuable
compounds in the reactions of cross-coupling with
organomagnesium and organozinc compounds at the
catalysis with palladium and nickel metallocomplexes
[1]. This situation promotes research and development
of new convenient methods of synthesis of the ortho-
carborane iodo-derivatives.
universal solvent for this reaction is glacial acetic acid.
It dissolves carborane and 9-bromocarborane, iodine,
and also is mixing with mineral acids and has a
sufficiently high boiling point. As an iodine oxidant a
mixture of concentrated sulfuric and nitric acids was
used. The process was carried out at 100°C, while
without heating the iodination did not occur.
The known methods of obtaining the majority of
the ortho-carborane iodo-derivatives are the reactions
of iodination in the presence of aluminum chloride
[2–8], as well as deborination of ortho-carborane with
subsequent addition of boron iodides [9]. Recent
studies of the synthesis of the ortho-carborane iodo-
derivatives belong to the synthesis of polyiodized
compounds [10–17].
We found that the oxidative iodination of ortho-
carborane can be carried out in stages, as a successive
replacement of the 1, 2, 3 and 4 hydrogen atoms in BH
fragments. Thus, under the action of one equivalent of
iodine on the ortho-carborane I a monoiodo-derivative,
9-I-1,2-C2B10H11 (III) is formed in 67% yield. The
reaction of the obtained 9-iodcarborane III with iodine
under similar conditions leads to a diiodo-derivative,
9,12-I2-1,2-C2B10H10 (IV), in 63% yield. The main
product of the reaction of the latter compound with
iodine is a triiodo-substituted carborane, 8,9,12-I3-1,2-
C2B10H9 (V) (yield 64%). Using the methods of gas
chromatography–mass spectrometry and NMR spec-
troscopy, we found that along with the main products
III and IV formed the corresponding regioizomers: 8-
I-1,2-C2B10H11 (IIIa) (yield 10%) and 8,9-I2-1,2-
C2B10H10 (IVa) (yield 18%). The synthesis of the triiodo-
derivative is accompanied with the formation of diiodo-
substituted carborane 9,12-I2-1,2-C2B10H10 (IV) (yield
The purpose of this study was to develop an
effective and convenient method of preparation of
tetraiodo-, bromotriiodo- and iodotribromcarboranes
and the products of their deborination, the potential
reagents for cross-coupling reactions.
For iodination of ortho-carborane 1,2-C2B10H12 (I)
and 9-bromo-ortho-carborane 9-Br-1,2-C2B10H11 (II)
we chose the method of oxidative iodination that had
been used previously for 9,11-diiodo-1,2-diphenyl-
ortho-carborane 1,2-Ph2-9,11-I2-1,2-C2B10H8 [18]. The
1137

1138
RUDAKOV et al.
9%) and teteraiodcarborane 8,9,10,12-I4-1,2-C2B10H9
(VI) (yield 11%). The synthesis of compounds IV and
V directly from the ortho-carborane is hardly
appropriate as a preparative method since a complex
mixture of iodo-derivatives is formed, as follows from
the data of gas chromatography–mass spectrometry.
Thus, iodination of ortho-carborane I with 1 mole of
iodine leads to a mixture consisting of monoiodized
product III (26%) and two diiodized regioizomers,
IVa (23%) and IV (51%), and the use of 1.5 mol of
iodine under similar conditions gives a mixture of two
diiodo- (5% of IVa + 62% of IV) and one triiodo-
derivative (17% of V). The final product of the
iodination of ortho-carborane with an excess of iodine
is the individual tetraiodocarborane 8,9,10,12-I4-1,2-
C2B10H8 (VI), formed in 91% yield.
corresponding iodo-substituted dicarbaundecaborates
which were isolated as the methylammonium salts
Me3NH+ [5-I-1,2-C2B10H11]– (VII) (yield 68%),
Me4N+ [5,6-I2-1,2-C2B10H10]– (VIII) (yield 62%),
Me4N+ [1,5,6-I3-1,2-C2B10H9]– (IX) (yield 96%) and
Kt+ [1,5,6,10-I4-1,2-C2B10H8]– [Kt+ = Me3NH+ (X)
(yield 74%), Kt+ = Me4N+ (XI)]. In the case of 8,9,12-
triiodo-1,2-dicarba-closo-dodecaborane (V) the deborina-
tion proceeds regioselectively at the atom B6 that is the
most distant from the core B8–I. We found that the
salts of tetraiodo-substituted dicarbaundecaborates X
and XI that differ by the type of cation (trimethylammo-
nium and tetramethylammonium, respectively) differ
significantly in solubility, which can be used for their
purification and isolation. Thus, compound XI is
soluble in DMSO and insoluble in acetone, whereas
substance X is readily soluble in both acetone and
dimethylsulfoxide.
Deborination of the carborane iodo-derivatives III–
VI with a solution of alkali in alcohol leads to the
−
3
H
7
C8
Kt+
11
C
C
(1) KOH, EtOH
7
1C
2
9
8
4
6
I
10
9
(2) Me3NHCl or Me4NBr
I
3
2
11 12
6
5
5
4
I
I
I
10
1
I
I
I
Kt+ = Me3NH+ (X), Me4N+ (XI)
VI
3
3
3
3
(1) CH3COOH,
(1) CH3COOH,
(1) CH3COOH,
0.5I2, 100oC
0.5I2, 100oC
0.5I2, 100oC
C
C
C
C
7
1C
2
7
1C
2
2
2
7
7
1 C
1C
8
4
6
I
I
8
8
8
4
6
4
6
4
6
(2) HNO3 + H2SO4
(2) HNO3 + H2SO4
(2) HNO3 + H2SO4
12
11
11 12
12
12
11
11
5
9
5
9
5
5
9
9
I
I
I
I
10
10
10
10
V
I
III
IV
(1) KOH, EtOH
(2) Me3NHCl
−
(1) KOH, EtOH
(2) Me4NBr
(1) KOH, EtOH
(2) Me4NBr
−
−
H
H
H
7
7
C
7C
C8
C8
11
11
C
11 Me4N+
Me3NH+
Me4N+
I
10
C8
9
10
10
9
9
3
2
3
2
3
2
6
6
5
6
4
5
1
4
5
4
I
1
I
I
1
I
I
VII
VIII
IX
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 6 2011

SYNTHESIS AND DEBORINATION OF POLYHALO-SUBSTITUTED ortho-CARBORANES
1139
Compounds III, IV, VI–VIII, X, and XI were
identified by comparing their physicochemical charac-
teristics and IR and 11B NMR spectra with the
published data [5, 11, 12]. The structure of products V
singlet signals of the molecular fragment B–I. In the
1H NMR spectra of compounds VII–X the signals of
terminal hydrogen groups B10–H are shifted
consecutively downfield, which indicates an increase
in electron-acceptor effect of iodine atoms with the
increase in their number in the cluster, and decrease in
the electron density in the open C2B3 pentagonal plane.
1
and IX was established on the basis of IR spectra, H,
11B, and 11B–{1H} NMR spectra, and 11B–11B COSY
experiments. We found that the 11B NMR spectrum of
compound X dissolved in acetone-d6 differs sig-
nificantly from the spectrum of compound XI in
DMSO-d6, although both compounds formally differ
only by the type of cation. Apparently, 7,8-
dicarbaundecaborate exists in acetone-d6 as a singly
charged anion, while in DMSO-d6 it is doubly charged,
which is confirmed by the published data concerning
related substances [11, 12, 19].
Under the same conditions as the iodination of
ortho-carborane, we performed the iodination of 9-
bromo-ortho-carborane, 9-Br-1,2-C2B10H11 (II), and
obtained
a
mixed bromotriiodo-derivative 9-Br-
8,10,12-I3-1,2-C2B10H8 (XII), in 83% yield. By the
action of bromine excess on 9-I-1,2-C2B10H11 (III) in
methylene chloride in the presence of aluminum
chloride iodotribromocarborane 9-I-8,10,12-Br3-1,2-
C2B10H8 (XIII) was synthesized in 92% yield.
11
The B NMR spectra of compounds III–X contain
3
3
C
C
7
1C
2
9
7
1C
2
9
8
4
6
8
4
6
11 12
11 12
5
5
(
2
)
H
3
N
I
Br
O
10
10
,
+
2
H
S
O
,
2
II
III
3
2
−
−
3
H
H
7C
7C
C8
2
C8
11
10
C
11
(1) KOH, EtOH
(2) Me3NHCl
(1) KOH, EtOH
(2) Me3NHCl
7
1C
10
2
9
3
8
9
4
6
+
+
Br
I
Y
Y
Me3NH
Me3NH
3
2
6
12
11
6
5
4
5
5
4
9
Br
I
1
10
1
X
I
Br
Y
Br
I
XV
XII, X = Br, Y = I
XIII, X = I, Y = Br
XIV
The structure of compounds XII and XIII was
established from IR, NMR, 11B, 11B–{1H}, and 11B–11B
COSY-spectra and gas chromatography–mass spec-
trometry. The mass spectra of the bromotriiodo- and
iodotribromo-derivatives XII and XIII contained
peaks of the corresponding molecular ions
[BrI3C2B10H8]+ (m/z = 601) and [IBr3C2B10H8]+ (m/z =
507), with maximum intensity in the respective
spectra.
singly charged clusters, Me3NH+ [5-Br-1,6,10-I3-7,8-
C2B9H8]– (XIV) (yield 72%) and Me3NH+ [5-I-1,6,10-
Br3-7,8-C2B9H8]– (XV) (yield 95%). The composition
and structure of compounds XIV and XV was
1
confirmed by the data of elemental analysis, IR, H
NMR, 11B, 11B–{1H}, and 11B–11B COSY spectra.
In the 1H NMR spectra of compounds XIV and XV
a characteristic broadening is seen of the quadruplets at
–0.12 and 0.16 ppm, respectively, of B(10)–H protons
located over the open pentagonal plane of the C2B3
core. In the IR spectra of the tetrahalo-substituted
compounds X, XIV, and XV a significant decrease
We performed deborination of compounds XII and
XIII by the action of excess alkaline alcohol, and
isolated respective trimethylammonium salts of the
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 6 2011

1140
RUDAKOV et al.
occurs in the intensity of the band corresponding to the
B–H stretching vibrations at 2500–2600 cm–1 in
comparison with the spectra of mono-, di-, and trihalo-
substituted carboranes III–V. In the spectrum of
compound XI two bands are observed at once, at 2562
and 2437 cm–1. In the IR spectra of compounds XIV
and XV, as in the spectra of undecaborates X and XI,
there are the absorption bands in the region of 900–
800 cm–1 corresponding to vibrations of B–Br and B–I
bonds.
9-I-1,2-C2B10H11 (III) (85%) and 8-I-1,2-C2B10H11
1
(IIIa) (13%). The total yield 79%. The H and 11B
NMR spectra of the resulting products III and IIIa
conform to the published data [11].
Synthesis of 9,12-I2-1,2-C2B10H10 (IV) was carried
out in a similar way using a mixture of regioizomers of
monoiodo-derivativas III and IIIa. A mixture of 8,9-
I2-1,2-C2B10H10 (22%) (IVa) and 9,12-I2-1,2-C2B10H10
(IV) (78% ) was obtained. The total yield 81%. The 1H
and 11B NMR spectra of the products IV and IVa
coincided with the published data [5, 11, 12].
The method of the oxidative iodination of ortho-
carborane and 9-bromo-ortho-carborane we have
developed is preferable compared to the known ap-
proaches to the iodination using elementary iodine in
the presence of Lewis acids [2–8] and iodination in a
sealed tube [12], because it can be easily scaled,
reduces the process duration, and does not require an
excess of iodine, which is especially important at the
introducing iodine isotopes in the synthesis of
carboranes for radiation diagnostics.
Synthesis of 8,9,12-I3-1,2-C2B10H9 (V) was per-
formed in the same way as the iodination of the
mixture of diiodo-ortho-carboranes IV and IVa ob-
tained by the method described above. A mixture
containing 9,12-I2-1,2-C2B10H10 (IV) (10%), 8,9,12-I3-
1,2-C2B10H9 (V) (75% ), and 8,9,10,12-I4-1,2-C2B10H9
(VI) (13%) was obtained. The total yield 80%. The
main product, 8,9,12-triiodo-ortho-carborane (V) was
isolated and purified by fractional crystallization from
a hexane–chloroform mixture, 5:2.
The IR spectrum of compound V, ν, cm–1: 3040 s,
2924 w, 2852 w, 2617 m, 1196 s, 1130 s, 1075 w,
1056 w, 1025 w, 973 s, 947 w, 928 s, 889 s, 870 s, 850
vs, 826 w, 799 s, 767 s, 742 s, 626 m.
1H NMR spectrum, δ, ppm: 5.33 s (2H, 2CHcarbs),
3.7–2.1 m (7H, 7BH). 11B NMR, δ, ppm: –6.0 d (1B,
B-10, JBH 156 Hz), –11.2 d (2B, B-4, B-7, JBH 180 Hz),
–11.7 s (2B, B-9, B-12), –12.4 d (2B, B-5, C-11, JBH
188 Hz), –13.6 d (1B, B-3, JBH 182 Hz), –15.3 d (1B,
B-6, JBH 201 Hz), –17.1 s (1B, B-8).
EXPERIMENTAL
IR spectra were recorded on a Fourier spectrometer
Protege-460, the samples were prepared as tablets with
1
KBr. The 11B and H NMR spectra were recorded on
an AVANCE-500 spectrometer from solutions of
substances in acetone-d6, for compound XI in DMSO-
1
d6. Chemical shifts are given relative to Me4Si for H
signals and Et2O·BF3 for 11B signals.
Chromato-mass spectra were obtained on an Agilent
6890N/5975 Inert instrument equipped with a capillary
column HP-5MS (30 m×0.25 mm×0.25 mm). Carrier
gas helium (0.8 ml min–1), evaporator temperature
250oC. The program of the evaporator oven: 50°C
(2 min), then raising the temperature to 300°C at a rate
20°C min–1. Ionizing energy 70 eV.
Synthesis of 8,9,10,12-I4-1,2-C2B10H8 (VI). To a
solution containing 1.0 g (6.9 mmol) of ortho-
carborane 1,2-C2B10H12 (I) and 3.5 g (13.8 mmol) of
iodine in 90 ml of glacial acetic acid heated to 100°C
was added dropwise at vigorous stirring within 30–45
min a mixture of concentrated sulfuric (45 ml) and
nitric (45 ml) acids. The reaction mixture was stirred
for 10 min and poured into ice water, the precipitate
was filtered off, dissolved in acetone, excess iodine
was neutralized with aqueous solution of sodium
sulfite. The solution was evaporated to 1/4 of the
original volume, the precipitate was separated, washed
with water (3×15 ml), dissolved in 90 ml of glacial
acetic acid and 1.5 g (5.9 mmol) of iodine was added
to it, and the resulting mixture was heated to 100°C.
Next, at vigorous stirring a mixture of concentrated
sulfuric (45 ml) and nitric (45 ml) acids was added
dropwise in 30–45 min, and then the solution was
Synthesis of 9-I-1,2-C2B10H11 (III). A solution of
0.5 g (3.47 mmol) of ortho-carborane 1,2-C2B10H12 (I)
and 0.44 g (1.74 mmol) of iodine in 90 ml of acetic
acid was heated to 100°C, a mixture of concentrated
sulfuric acid (20 ml) and nitric acid (20 ml) was added
dropwise within 20–25 min at vigorous stirring, and
the mixture was stirred until the disappearance of
iodine color. Then the solution was poured into the ice
water, the precipitate was filtered off, dissolved in
acetone, reprecipitated by adding water, and dried in a
vacuum over CaCl2. A mixture (0.74 g) was obtained,
containing, according to 1H NMR and 11B spec-
troscopy and gas chromatography–mass spectrometry,
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 6 2011

SYNTHESIS AND DEBORINATION OF POLYHALO-SUBSTITUTED ortho-CARBORANES
1141
stirred for another 10 min and poured into ice water.
The precipitate was filtered off, dissolved in acetone,
excess iodine was neutralized with aqueous solution of
sodium sulfite. The solution was evaporated to 1/4 of
the original volume, the precipitate was filtered off,
washed with water (3×15 ml), and dried over CaCl2.
4.07 g (6.28 mmol) of 8,9,10,12-I4-1,2-C2B10H8 was
w, 928 s, 889 s, 870 s, 850 vs, 826 w, 799 s, 767 s, 742
s, 626 m.
1H NMR spectrum, δ, ppm: 5.22 s (1H, CHcarb),
5.08 s (1H, CHcarb), 3.8–1.8 m (6H, 6BH).
11B NMR spectrum, δ, ppm: 1.1 (1B, B-12-Br),
–5.5 s (2B, B-8-Br, B-10-Br), –10.9 s (1B, B-9-I),
–13.7 d (4B, B-4, B-5, B-7, B-11, JBH 166 Hz), –18.9 d
(2B, B-3, B-6, JBH 184 Hz).
1
obtained, yield 91%. The H and 11B NMR spectral
data of the obtained compound VI coincided with the
published ones [12].
Synthesis of Me4N+ [1,5,6-I3-7,8-C2B9H9]– (IX).
To a solution of 1.56 g (3.0 mmol) of 8,9,12-I3-1,2-
C2B10H9 V in 10 ml of anhydrous ethanol was added
0.35 g (6.0 mmol) of potassium hydroxide and the
mixture was refluxed while stirring for 3.5 h, after
which the reaction mixture was evaporated to dryness
and to it water was added. Unreacted triiodide (IX)
was filtered off. To the filtrate was added 0.62 g
(4 mmol) of tetramethylammonium bromide in 10 ml
of water. The precipitate was filtered off, dissolved in
acetone, the solution was filtered, the filtrate was
evaporated to dryness, washed with water (3 × 10 ml)
and dried over CaCl2. 1.26 g of Me4N+[1,5,6-I3-7,8-
C2B9H9]– (IX) was isolated. Yield 96%.
IR spectrum, ν, cm–1: 3049 w, 3023 w, 2947 w,
2913 w, 1479 OS, 1447 w, 1415 w, 1287 w, 1253 w,
1172 m, 1082 s, 1018, 984 w, 948 a, 927 s, 858 s, 825
s, 812 s, 760 s, 712 w, 635 w, 603 w.
1H NMR spectrum, δ, ppm: 3.43 s (12H, Me4N),
3.0–0.8 m (8H, 8B-H), 2.31 s (2H, 2CHcarb), –1.62 d
(1H, B-10-H, JBH 62 Hz).
Synthesis of 9-Br-8,10,12-I3-1,2-C2B10H8 (XII).
To a solution containing 0.63 g (2.83 mmol) of 9-Br-
1,2-C2B10H11 and 3.0 g (11.81 mmol) of iodine in
90 ml of glacial acetic acid, heated to 100°C, at stirring
a mixture of concentrated sulfuric (45 ml) and nitric
(45 ml) acids was added dropwise over 40 min. The
reaction mixture was stirred for 10 min and poured
into ice water. The precipitate was filtered off,
dissolved in acetone, excess iodine was neutralized
with aqueous solution of sodium sulfite. The solution
was evaporated to 1/4 of the original volume, the
precipitate was filtered off and washed with water
(3×15 ml). The resulting product was purified by
reprecipitation with water from acetone and then by
hexane from ether. 1.42 g (2.36 mmol) of 9-Br-
8,10,12-I3-1,2-C2B10H8 (XII) was obtained, yield 83%.
IR spectrum, ν, cm–1: 3031 vs, 2970 w, 2925 w,
2839 w, 2624 s, 1382 m, 1199 s, 1132 m, 1103 m 1076
m 1019 m, 981 mr, 962 s, 943 s, 918 w, 882 vs, 821 w,
842 vs, 821 w, 795 s, 763 m, 742 s, 632 m, 616 m.
1H NMR spectrum, δ, ppm: 5.48 s (1H, CcarbH),
5.29 (1H, CcarbH), 3.31–2.24 m (6H, 6BH).
11B NMR spectrum, δ, ppm: 2.1 s (1B, B-9), –9.5 s
(1B, B-12), –12.0 d (4B, B-4, B-5, B-7, B-11, JBH
165 Hz), –15.8 d (2B, B-3, B-6, JBH 187 Hz), –18.9 s
(2B, B-8, B-10).
11B NMR spectrum, δ, ppm: –8.9 d (2B, B-9, B-11,
JBH 148 Hz), –15.3 d (1B, B-3, JBH 181 Hz), –18.5 d
(2B, B-2, B-4, JBH 164 Hz), –20.7 s (2B, B-5, B-6), d.d
–26.8 (1B, B-10, JBH 139, JBH 32 Hz), –35.1 s (1B, B-1).
Found, %: C 12.66; H 4.11; B 16.76; I 65.03; N
2.57. C6H21B9I3N. Calculated, %: C 12.31; H 3.62; B
16.63; I 65.05; N 2.39
Synthesis of Me3NH+[5-I-7,8-C2B9H11]– (VII),
Me4N+ [5,6-I2-7,8-C2B9H10]– (VIII), Me3NH+
[1,5,6,10-I4-7,8-C2B9H8]– (X), Me4N+ [1,5,6,10-I4-7,8-
C2B9H8]– (XI), (XIV) and (XV) was carried out
similarly to carboranes III, IV, VI, XII, and XIII,
respectively.
Compound XIV. IR spectrum, ν, cm–1: 3122 s,
3042 w, 2957 w, 2923 w, 2853 w, 2731 w, 2561 s,
1475 s, 1462 vs, 1448 s, 1411 m, 1372 m, 1247 m,
1168 w, 1079 m, 1042 w, 1013 m, 971 s, 926 s, 897 w,
879 w, 860 m, 818 s, 757 m, 642 w, 621 w, 579 w.
Synthesis of 9-I-8,10,12-Br3-1,2-C2B10H8 (XIII).
To a solution of 1.65 g (6.1 mmol) of 9-I-1,2-C2B10H11
in 30 ml of methylene chloride containing 0.5 g AlCl3
was added 1.5 ml (4.65 g, 29.0 mmol) of bromine, and
the mixture was refluxed for 3.5 h. Then the solution
was evaporated to dryness, to the residue water was
added to neutralize AlCl3, the product was extracted
with methylene chloride and dried over CaCl2. After
removal of the solvent 2.85 g (5.62 mmol) of com-
pound 9-I-8,10,12-Br3-1,2-C2B10H8 (XIII) was ob-
tained, yield 92%.
IR spectrum, ν, cm–1: 3040 s, 2924 w, 2852 w, 2617
m, 1196 s, 1130 s, 1075 w, 1056 w, 1025 w, 973 s, 947
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 6 2011

1142
RUDAKOV et al.
1H NMR spectrum, δ, ppm: 3.14 s (12H, Me4N),
2. Smith, H.D., Knowles, T., and Schroeder, H.A., Inorg.
Chem., 1965, vol. 4, no. 1, p. 107.
2.44 s (1H, CHcarb), 2.31 s (1H, CHcarb), 3.0–1.3 m (5H,
3. Zakharkin, L.I. and Kalinin, V.N., Izv. Akad. Nauk
5BH), –0.12 br.q (1B, B-10-H, JBH 75 Hz, 179 Hz).
SSSR, Ser. Khim., 1966, no. 3, p. 575.
11B NMR spectrum, δ, ppm: –7.0 s (1B, B-5-Br),
–9.7 d (2B, B-9, B-11, JBH 146 Hz), –17.0 d (1B, B-3,
4. Andrews, J.S., Zayas, J., and Jones, M., Jr., Inorg.
Chem., 1985, vol. 24, no. 22, p. 3715.
J
BH 193 Hz), –18.4 d (1B, B-2, JBH 193 Hz), –19.5 q+s
5. Li, J., Logan, C.F., and Jones, M., Jr., Inorg. Chem.,
(2B, B-4, B-6-I, JBH 159 Hz), –36.0 q+s (1B, B-10-H +
B-10-I, JBH 89 Hz), –36.5 s (1B, B-1).
1991, vol. 30, no. 25, p. 4866.
6. Zakharkin, L.I., Stanko, V.I., and Klimova, A.I., Izv.
Akad. Nauk SSSR, Ser. Khim., 1966, no. 11, p. 1946.
Found, %: C 9.69; H 2.95; B 14.57; Hlg 70.55; N
2.31. C5H18B9I3BrN. Calculated, %: C 9.24; H 2.79; B
14.97; Hlg 70.85; N 2.15.
Compound XV. IR spectrum, ν, cm–1: 3136 s,
3045 w, 2959 w, 2924 w, 2853 w, 2786 w, 2752 w,
2541 s, 1477 vs, 1465 a, 1451 vs, 1414 m 1372 m
1252 m, 1174 w, 1086 s, 1045 w, 1019 s, 973 vs, 953
w, 930 s, 900 w, 874 s, 824 vs, 759 m, 650 w, 630 w,
609 w, 579 w, 533 w.
1H NMR spectrum, δ, ppm: 3.16 s (5H, Me3NH),
3.15 s (4H, Me3NH), 2.35 s (1H, CHcarb), 2.26 s (1H,
CH carb), 2.8–0.6 m (5H, 5BH), 0.16 br.q (1H, B-10-H,
BH 74 Hz, 178 Hz).
11B NMR spectrum, δ, ppm: –7.4 s (1B, B-6-Br),
7. Zakharkin, L.I. and Kalinin, V.N., Izv. Akad. Nauk
SSSR, Ser. Khim., 1969, no. 3, p. 607.
8. Stanko, V.I., Klimova, A.I., and Klimova, T.P., Zh.
Obshch. Khim., 1967, vol. 37, no. 10, p. 2236.
9. Ramachandran, B.M., Knobler, C.B., and Hawthorne, M.F.,
Inorg. Chem., 2006, vol. 45, no. 1, p. 336.
10. Yamazaki, H., Ohta, K., and Endo, Y., Tetrahodron
Lett., 2005, vol. 46, no. 17, p. 3119.
11. Barbera, G., Vaca, A., Teixidor, F., Sillanpaa, R.,
Kivecas, R., and Vinas, C., Inorg. Chem., 2008, vol. 47,
no. 16, p. 7309.
12. Vaca, A., Doctorate (Chem.) Dissertation, Barcelona,
2007.
J
13. Vaca, A., Teixidor, F., Kivekas, R., Sillanpaa, R., and
Vinas, C., Dalton Trans., 2006, no. 41, p. 4884.
–10.7 d (2B, B-9, B-11, JBH 147 Hz), –20.0 d + s (3B,
B-3, B-4 + B-5-I, JBH 155 Hz), –21.0 d (1B, B-2, JBH
143 Hz), –23.7 s (1B, B-1-Br ), –24.3 q + s (1B, B-10-
H + B-10-Br, JBH 51 Hz).
14. Srivastava, R.R., Halmin, D.K., and Wilbur, D.S.,
J. Org. Chem., 1996, vol. 61, no. 25, p. 9041.
15. Barbera, G., Teixidor, F., Vinas, C., Sillanpaa, R., and
Kivekas, R., Eur. J. Inorg. Chem., 2003, no. 8, p. 1511.
16. Teixidor, F., Barbera, G., Kivekas, R., Sillanpaa, R., and
Found, %: C 11.26; H 3.03; B 17.62; Hlg 65.50; N
2.51. C5H18B9Br3IN. Calculated, %: C 10.80; H 3.26;
B 17.50; Hlg 65.92; N 2.52.
Vivas, C., Dalton Trans., 2007, no. 17, p. 1668.
17. Teixidor, F., Barbera, G., Vinas, C., Sillanpaa, R., and
Kivekas, R., Inorg. Chem., 2006, vol. 45, no. 9, p. 3496.
18. Robertson, S., Ellis, D., McGrath, T.D., Rosair, G.M.,
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1. Kalinin, V.N. and Ol’shevskaya, V.A., Izv. Akad. Nauk,
Ser. Khim., 2008, no. 4, p. 801.
19. Barbera, G., Doctorate (Chem.) Dissertation, Barcelona,
2002.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 81 No. 6 2011