Phenyliodine(V) fluorides

Article abstract of DOI:10.1016/j.jfluchem.2003.12.004

The known compound phenyltetrafluoroiodine(V) is shown by X-ray diffraction to have a tetragonal pyramidal structure with an apical phenyl group. This structure is compared to that of IF(OTeF₅)₄, where the apical position is occupied

Full text of DOI:10.1016/j.jfluchem.2003.12.004

Journal of Fluorine Chemistry 125 (2004) 989–996
Phenyliodine(V) fluorides
Sevim Hoyer, Konrad Seppelt*
¨ ¨
Institut fur Chemie der Freien Universitat, Fabeckstraße 34-36, D-14195 Berlin, Germany
Received 18 November 2003; received in revised form 18 November 2003; accepted 3 December 2003
Available online 28 January 2004
Abstract
The known compound phenyltetrafluoroiodine(V) is shown by X-ray diffraction to have a tetragonal pyramidal structure with an apical phenyl
group. This structure is compared to that of IF(OTeF5)4, where the apical position is occupied by the fluorine atom. C6H5IF4 adds Fꢀ, forming
C6H5IF5ꢀ, which has a pentagonal pyramidal structure with an apical phenyl group. Fluoride abstraction from C6H5IF4 by SbF5 results in the
formation of the cation C6H5IF3þ, which has a pseudotrigonal bipyramidal structure with the phenyl group occupying an equatorial position.
Isoelectronic C6H5IOF2 has a similar structure, with the phenyl group and oxygen atom both occupying equatorial positions.
# 2003 Elsevier B.V. All rights reserved.
Keywords: Phenyliodine tetrafluoride; Phenyltetrafluoroiodine(V); Phenylpentafluoroiodate(1–); Phenyltrifluoroiodonium cation; Phenyldifluorooxoiodi-
ne(V); Iodine fluoride; Fluoro(fluorotetrakis(pentafluorotellurato)iodine(V); Structure determination
1. Introduction
since 1901 [10], can be considered as the first hydrolysis
product of C6H5IF4, (although it is more conveniently pre-
pared from C6H5IO2). Its precise structure had not been
determined, so it is also reported in this paper.
The compound C6H5IF4 has been known since 1968 [1].
Aryl iodine tetrafluorides can be prepared by three different
methods: (1) fluorination of ArI [2]; (2) arylation of IF5 [3];
and (3) conversion of ArIO2 into ArIF4 with SF4 [1]. It has
always been assumed that the aryl group in these compounds
is positioned at the apex of a tetragonal pyramid, with the
four fluorine atom occupying basal positions. The key
evidence for this particular geometric isomer comes from
19F NMR spectra, which in all cases and under all conditions
shows only a single line, and by analogy with the known
structures of C6F5IF4 and CF3IF4 [4,5]. This structure is
predicted by a simple bonding model: the longer 3-center-4-
electron basal bonds in a square pyramid can better accom-
modate the more electronegative fluorine atoms relative to
the shorter apical 2-center-2-electron apical bond.
A precise structure of the parent compound C6H5IF4 is
presented in this paper. Little is known about the chemical
reactions of these compounds, so we have also studied two
of their simplest possible reactions, the addition and loss of a
fluoride ion. The formation of both IF6ꢀ and IF4þ from IF5 is
known since long [6–9]. The question was whether C6H5IF4
can also act as fluoride ion acceptor and/or donor, and what
the resulting structures would be. Finally, C6H5IOF2, known
2. Results and discussions
2.1. C6H5IF4
The reaction of C6H5IO2 with SF4 is the method of choice
for the preparation of C6H5IF4 [1]. The reaction is nearly
quantitative, and the gaseous byproducts can be removed
easily. C6H5IF4 is a crystalline material with surprising
thermal stability to about 300 8C. However, it hydrolyses
quickly. The 19F NMR spectrum shows the same single line
regardless of the method of preparation, so there is no
indication of geometric isomerism. The chemical shift is
somewhat solvent dependent, indicating varying strengths of
interaction with various solvents. Crystal structure determi-
nations of iodine(V)fluorides are rare, although the square-
pyramidal structure of IF5, with a very complex set of
intermolecular interactions, has long been known [11]. More
recently, the crystal structures of C6F5IF4 and CF3IF4 have
appeared [4,5]. In these two molecular structures the
expected square pyramidal geometry with the organic sub-
stituent in the apical position was confirmed.
* Corresponding author. Fax: þ49-30-8385-3310.
Single crystals of C6H5IF4 were readily obtained from
a diethylether solution at ꢀ50 8C. The resulting crystal
E-mail address: seppelt@chemie.fu-berlin.de (K. Seppelt).
0022-1139/$ – see front matter # 2003 Elsevier B.V. All rights reserved.
doi:10.1016/j.jfluchem.2003.12.004

990
S. Hoyer, K. Seppelt / Journal of Fluorine Chemistry 125 (2004) 989–996
Fig. 1. Structure of C6H5IF4 in the crystal, ortep representation, 50% probability ellipsoids.
structure is shown in Fig. 1, and interatomic distances and
angles are listed in Table 1. While the same basic structure of
CF3IF4 and C6H5IF4 is clearly evident, the intermolecular
interactions are noteworthy. Basal fluorine atoms make
contacts to neighboring iodine atoms, resulting in a zigzag
chain. The I–F bond lengths (average 194 pm) are longer
than in IF5 (average 187 pm), CF3IF4 (average 192 pm), or
C6F5IF4 (average 191 pm). This is certainly a consequence
of the weaker electron withdrawing power of a C6H5 group
compared to F, CF3, or C6F5 substituents. The I–C bond
length of 207.7 pm is nearly the same as in C6F5IF4
(208 pm) and much shorter than in CF3IF4 (222 pm). The
average C–I–F angle of 85.358 is slightly larger than the
average C–I–F angles in other iodine(V) compounds such as
IF5 (81.98), CF3IF4 (82.18), and C6F5IF4 (84.38).
reaction product of IF5 and B(OTeF5)3, and this is still the
method of choice for its preparation [12,13]. Note that the
fifth fluorine atom is not substituted in this reaction. But the
compound I(OTeF5)5 can be made by the reaction of
I(OTeF5)3 with Xe(OTeF5)2 [12,13].
Analysis of the 19F NMR spectrum of IF(OTeF5)4 led to
the conclusion that the fluorine atom occupies the axial
position and the four OTeF5 groups occupy the four equiva-
lent basal positions of a square pyramid. This assignment is
confirmed by the single crystal X-ray structure determina-
tion. Interatomic distances and angles are listed in Table 2.
The structure, shown in Fig. 2, consists of square pyramidal
IF(OTeF5)4 molecules with only weak intermolecular inter-
actions (similar to the weak interactions typically observed
in most OTeF5 compounds). There is the same umbrella-type
structure observed for C6H5IF4. The F–I–O angles are 85.50
and 80.238. The noteworthy difference is the apical fluorine
atom. This finding once has led to the unlikely conclusion
that the OTeF5 group may be more electronegative than
fluorine [12,13]. However, the preference of substituents for
apical versus basal positions seems to be governed by other,
2.2. IF(OTeF5)4
Although belonging to a different class of compounds, we
wanted to compare the molecular structure of C6H5IF4 with
IF(OTeF5)4. This compound was first described as the final
Table 1
Table 2
Important bond distances (pm) and angles (8) of FI(OTeF5)4
Important bond distances (pm) and angles (8) of C6H5IF4
I–F1
I–F2
I–F3
I–F4
I–C1
C–C
195.7 (3)
F1–I–C1
F2–I–C1
F3–I–C1
F4–I–C1
84.2 (2)
85.7 (1)
85.5 (1)
86.0 (2)
I–F1
182.7(4)
F1–I–O1
F1–I–O2
O1–I–O10
O2–I–O20
O1–I–O2
F–Te–F
85.5 (1)
194.8 (3)
192.1 (3)
I–O1
193.9(3)
80.2 (1)
I–O2
200.6(3)
171.0 (2)
193.6 (3)
Te1–O1
Te2–O2
Te–F
188.3(3)
186.0(3)
160.5 (2)
87.7 (7)
207.7 (4)
137.7 (4)–140.0 (4)
87 (3)–96 (4)
307.4 (3)
181.5(3)–184.0(3)
87.0 (1)–91.3 (2),
176.1 (1)–178.5 (1)
88.4 (1)–92.8 (2),
177.5 (1), 178.4 (1)
C–H
IÁ Á ÁF1
IÁ Á ÁF2
C1–IÁ Á ÁF1
C1–IÁ Á ÁF2
146.5 (2)
142.2 (2)
F–Te–O
323.4 (3)

S. Hoyer, K. Seppelt / Journal of Fluorine Chemistry 125 (2004) 989–996
991
Fig. 2. Structure of FI(OTeF5)4 in the crystal, ortep representation, 50%
probability ellipsoids.
more subtle effects than in addition to substituent electro-
negativity. Nevertheless, it should be kept in mind that
OTeF5 containing compounds are often quite similar to
the corresponding fluorides.
ꢀ
2.3. C6H5IF5
Fig. 3. Structure of C6H5IF5 in pipþC6H5IF5 CH3CN. Shown is the
weakly associated dimeric anion. For an overview of the entire structure
see deposited data.
ꢀ
ꢀ
The intermolecular IÁ Á ÁF contacts in C6H5IF4 indicate that
the iodine atom might act as a fluoride ion acceptor and the
fluorine atoms as donor ligands. The chemical realization in
the first case would be the reaction of C6H5IF4 with Fꢀ. We
have chosen 1,1,3,3,5,5-hexamethylpiperidinium fluoride
(pipþFꢀ) as a source of Fꢀ [14]. This salt contains a large
quaternary ammonium cation and can thus be considered a
source of nearly ‘‘naked’’ fluoride ions. Its Fꢀ donor ability
is better than those of the more commonly used reagents CsF
and (CH3)4NþFꢀ [15]. Furthermore, the irregular shape of
the cation does not promote crystallographic disorder as
does the symmetric geometry of the (CH3)4Nþ cation. The
multistep preparation of pipþFꢀ is the price one must pay to
accrue these advantages [14].
The compound C6H5IF4 reacted with pipþFꢀ in acetoni-
trile at ꢀ30 8C, forming colorless, hydrolytically sensitive
pipþC6H5IF5ꢀ. The compound was characterized by Raman
and NMR spectroscopy and by its single crystal structure
determination. The 19F NMR spectrum shows only one line,
indicating either static or dynamic equivalence of all five
fluorine atoms. The crystal structure, shown in Fig. 3,
revealed the composition pipþ C6H5IF5ꢀÁCH3CN. Intera-
tomic distances and angles are listed in Table 3. The
acetonitrile molecules act as spacers between the cation/
anion layers and do not seem to have much influence on the
coordination geometry of the iodine atom.
There are weak interactions between the fluorine atoms
and the methyl protons of the pipþ cation. Interestingly, the
anions come in pairs due to four weak IÁ Á ÁF interactions of
324.5(1) and 339.2(1) pm length. Each C6H5IF5ꢀ anion has
the shape of a regular pentagonal IF5 unit with an apical
phenyl group. Compared with C6H5IF4, the I–F bonds are
elongated to 202 pm (average) and the I–C bond is elongated
to 209.4(1) pm. The C–I–F angles are below 908 (84.76(5)–
88.73(5)8). Such pentagonal molecular geometries are rare,
ꢀ
but not without precedent. Two relevant example are XeF5
[16] and IF52ꢀ [17]. Eꢀven more relevant are the chemically
2ꢀ
similar anions XeOF5 [18,19] and IOF5 [20] that have
the same pentagonal-pyramidal structure. The first examples
of pentagonal-pyramidal coordination was observed in iso-
electronic Te(IV) dithiocarbamates [21].
It would have been difficult to predict the correct structure
for C6H5IF5ꢀ. Although the aforementioned anions aꢀll
contain the pentagonal AF5 unit, the related species IF6

992
S. Hoyer, K. Seppelt / Journal of Fluorine Chemistry 125 (2004) 989–996
The strongꢀband at 503 cmꢀ1 in the Raman spectrum of
Table 3
ꢀ
pipþC6H5IF5 has been tentatively assigned to ns(IF5)
(assuming local Cꢀ5v symmetry) by analogy with the assign-
ments for XeOF5 and IOF52ꢀ, where the corresponding
Important bond distances (pm) and angles (8) of C6H5IF5 in
pipþC6H5IF5ꢀÁCH3CN
I–F1
I–F2
I–F3
I–F4
I–F5
I–C1
C–C
203.4 (1)
202.1 (1)
bands are found at 451 and 485 cmꢀ1
.
201.2 (1)
200.6 (1)
þ
ꢀ
2.4. C6H5IF3 SbF6
202.7 (1)
209.4 (2)
138.4 (2)–139.1 (2)
92 (2)–96 (2)
339.2 (1)
The reaction of C6Hꢀ5IF4 with SbF5 in anhydrous HF
afforded C6H5IF3þSbF6 as colorless platelets. The com-
pound is stable only below ꢀ20 8C. The crystal structure,
shown in Fig. 4, revealed that the cation and anion are
interconnected by Sb–FÁ Á ÁI bridges, resulting in a chain-
like arrangement. Interatomic distances and angles are
C–H
IÁ Á ÁF2
IÁ Á ÁF3
F–I–F
324.9 (1)
71.21 (4)–72.57 (4)
142.34 (4)–144.33 (4)
F1–I–C1
F2–I–C1
F3–I–C1
F4–I–C1
F5–I–C1
88.64 (5)
84.76 (5)
88.34 (5)
85.73 (5)
85.97 (5)
ꢀ
listed in Table 4. The angles within the SbF6 anions
are close to 90 and 1808. The Sb–F distances involving
the bridging F atoms are only slightly elongated. If the
cations are viewed as isolated species, they exhibit the
expected SF4-type structure, with a relatively linear F–I–F
fragment (163.0(2)8) with I–F bond length of 189.4(3) and
189.9(3) pm. The third fluorine atom (IꢀF ¼ 182:1(3) pm)
and the ipso carbon atom (IꢀC ¼ 208:4(5) pm) occupy
equatorial positions in the pseudo-trigonal-bþipyramidal
structure. The cations ClF4þ, BrF4þ, and IF4 all have
similar structures [29]. The two Sb–FÁ Á ÁI contacts to
and XeF6 are best described as C3v-monocapped c-octahe-
dra (for a short review on the structure of XeF6 in the gaseous
state [9,22,23]). The reason for this structural ambiguity is
clearly the number of seven electron pairs at iodine. It is well
known that the three possible geometries for an AF7 species
(pentagonal bipyramid and C3v- and C2v-monocapped octa-
hedra) are very close in energy. To complicate matters
further, someꢀAB6E species (E: nonbonding electron pair),
such as BrF6 and ClF6ꢀ, have regular octahedral geome-
tries [14,24–27]. Octahedral symmetry seems to prevail
when the central atom is small or the ligand atoms are large
(TeI62ꢀ) [28].
ꢀ
ꢀ
neighbouring SbF6 units in C6H5IF3þSbF6 complete
the pseudo-pentagonal-bipyramidal structure with two
axial fluorine atoms. The chain-like arrangement of cations
and anionsꢀ is very similar to the crystal structures of
ClF4þSbF6 and BrF4þSbF6ꢀ. In IF4þSbF6ꢀ, however,
the cation-anion interactions result in a nine-coordinate
environment around the iodine atom. In summary, the five
equatorial positions in C6H5IF3þSbF6ꢀ are occupied by the
Fig. 4. Structure of C6H5IF3þSbF6ꢀ, ortep representation, 50% probability ellipsoids. Shown is the bridged cation-anion chain.

S. Hoyer, K. Seppelt / Journal of Fluorine Chemistry 125 (2004) 989–996
993
Fig. 5. Structure of C6H5IOF2 the four crystallographic different molecules, ortep representation, 50% probability ellipsoids.
phenyl-group carbon atom, one strongly bonded fluorine
atom, two bridging fluorine atoms from SbF6ꢀ anions, and
the non-bonding electron pair. A similar pentagonal envir-
onment but with three strongly bonded fluorine atoms in a
T shape and two longer contacts to fluorine atoms from
neighboring molecules was found in crystalline IF3 [30].
2.5. C6H5IOF2
The original preparation of C6H5IOF2 is easily reproduced
[10]. It is a colorless crystalline solid that is stable up to 2168,
at which temperature it decomposes with a mild explosion.
The two fluorine atoms are equivalent by 19F NMR spectro-
scopy. In the Raman spectrum the I¼O and IF stretching
frequencies can be assigned. A pseudo trigonal bipyramidale
structure is established by a single crystal structure determi-
nation. There are four crystallographically distinct molecules
in the asymmetric unit as shown in Fig. 5 and Table 5. The
average I–F bond distance of 195.5(3) is only a little longer
Table 4
Important bond distances (pm) and angles (8) of C6H5IF3þSbF6
ꢀ
I–F7
I–F8
182.7 (3)
189.9 (3)
I–F9
189.4 (3)
I–C1
C–C
208.4 (5)
Table 5
136.8 (9)–139.6 (10)
85 (5)–95 (6)
187.9 (3)
Important bond distances (pm) and angles (8) of C6H5IOF2, four
crystallographic different molecules in the unit, n ¼ 1–4
C–H
Sb–F1
Sb–F2
Sb–F3
Sb–F4
Sb–F5
Sb–F6
IÁ Á ÁF3
IÁ Á ÁF5
F7–I–F8
F7–I–F9
F8–I–F9
C1–I–F7
C1–I–F8
C1–I–F9
F3Á Á ÁIÁ Á ÁF5
F–Sb–F
186.6 (3)
191.5 (3)
I(n)–O(n)
I(n)–F(n1)
I(n)–F(n2)
I(n)–C(n1)
C–C
179.0 (4), 178.1 (4), 177.9 (4), 178.6 (4)
194.9 (3), 196.2 (3), 195.3 (3), 193.9 (3)
196.9 (3), 195.0 (3), 196.3 (3), 196.8 (3)
210.1 (6), 210.7 (5), 209.7 (5), 209.1 (5)
135.3 (9)–139.7 (8)
186.3 (3)
187.7 (3)
186.2 (3)
255.9 (3)
C–H
78 (5)–101 (5)
279.9 (3)
IÁ Á ÁO
266.9 (4), 271.1 (4), 272.6 (4), 288.5 (4),
290.2 (4), 291.2 (4)
303.8 (3), 329.2 (3)
82.0 (2)
81.8 (2)
IÁ Á ÁF
163.0 (2)
O(n)–I(n)–F(n1)
O(n)–I(n)–F(n2)
O(n)–I(n)–C(n1)
F(n1)–I(n)–F(n2)
F(n1)–I(n)–C(n1)
F(n2)–I(n)–C(n1)
90.9 (2), 90.1 (2), 91.6 (2), 90.0 (2)
91.6 (2), 91.1 (2), 92.0 (2), 93.2 (2)
99.4 (2), 101.2 (2), 100.0 (2), 98.7 (2)
171.3 (1), 174.0 (2), 173.2 (2), 170.7 (3)
85.8 (2), 86.4 (2), 86.5 (2), 87.4 (2)
85.6 (2), 87.6 (2), 87.2 (2), 83.5 (2)
96.5 (2)
87.4 (2)
89.2 (2)
117.2 (2)
88.4 (2)–91.6 (2), 176.9 (2)–179.6 (2)

994
S. Hoyer, K. Seppelt / Journal of Fluorine Chemistry 125 (2004) 989–996
than in the isoelectronic species C6H5IF3þ. The average I–O
bond length of 178.4(4) pm is typical for an I¼O double
bond. The solid-state packing is dominated by I¼OÁ Á ÁI
bridges of 266.9(4), 271.1(4), and 272.6(4) pm, resulting
in infinite molecular chains. The chains are interconnected
by longer I¼OÁ Á ÁI contacts (288.2(4), 290.2(4), and 291.2(4)
pm) and I–FÁ Á ÁI contacts (>300 pm), resulting in the forma-
tion of infinite double chains.
refinement of the structures were done using the SHELXL
programs version 1993 and 1997 [32]. All atoms except
hydrogen are refined anisotropically. Hydrogen atoms are
refined with one (isotropic) displacement factor for all
hydrogen atoms.
3.2. Starting materials
C6H5IO2 [33], B(OTeF5)3 [34], 1,1,3,3,5,5 hexamethyl-
piperidiumfluoride [14] are prepared following literature
procedures. SF4, IF5, and SbF5 are available from laboratory
stock and are vacuum distilled prior to use. IF5 is treated with
a small pressure of elemental fluorine prior to the distillation
to remove traces of elemental iodine. Anhydrous HF is
obtained by several distillations in metal vacuum lines from
commercial HF (ꢁ99%).
3. Experimental details
3.1. General techniques
All reactions were performed in dried glass or PFA
(Polyperfluoroethene perfluorovinylether) tubes under an
argon atmosphere or under vacuum. Solvents were dried
using conventional procedures. Water- and oxygen-sensitive
compounds were handled in an argon-filled dry box (UB 150
B/G) with residual H2O/O2 contents of less than 1 ppm.
NMR spectra were recorded on a 400 MHz multinuclear
JEOL Lambda 400 spectrometer. Chemical shifts are rela-
tive to tetramethylsilane (1H, 13C) or CFCl3 (19F). Raman
spectra were recorded in glass or PFA capillaries with a
Bruker model RFS 100 FT-Raman spectrometer using
1064 nm Nd-YAG laser excitation and an energy of 5–
550 mW.
Single crystal structures were determined using an Enraf-
Nonius CAD 4 four circle diffractometer or on a Bruker
Smart-CCD-1000 M diffractometer. Both instruments are
equipped with a Mo Ka, (l ¼ 0:71073 pm) X-ray source
and a graphite monochromator. Crystals were cut, when
necessary, and mounted under cooled nitrogen using a
special device of local design [31]. Absorption correction:
CAD4: c scan method, CCD: equilibration of symmetry
related reflections (SADABS procedure). Solution and
3.3. Synthesis of C6H5–IF4
A 50 ml stainless steel autoclave is filled with 4.72
(20 mmol) C6H5IO2, and 13 ml CHCl3 is added [1]. At
ꢀ196 8C 6.5 g (60 mmol) SF4 is condensed in. The auto-
clave is heated 2 h at 70, 100, and 1308, and finally 3 h at
150 8C. At room temperature all volatile material is pumped
into a ꢀ1968 cold trap and disregarded. C6H5IF4 is obtained
essentially quantitative as a slightly yellow, hydrolytically
sensitive crystalline solid. 19F(Et2O) d ¼ ꢀ25:63 ppm. Sui-
table crystals are obtained from a Et2O solution that is
cooled slowly to ꢀ50 8C. Experimental details of the crystal
structures and results are laid down in Tables 1 and 6.
3.4. Synthesis of 1,1,3,3,5,5 hexamethyl ꢀpiperidinium
phenyl pentafluoro iodate pipþ C6H5IF5
In the drybox 140 mg (0.5 mmol) C6H5IF4 and 150 mg
(0.8 mol) pipþFꢀ are weighed into a 12 mm inner diameter
Table 6
Experimental detail for the crystal structure determinations
pipþC6H5IF5 CH3CN
C6H5IF3 SbF6
C6H5IOF2
ꢀ
ꢀ
ꢀ
Compound
C6H5IF4
FI(OTeF5)4
Formula
a (pm)
C6H5F4I
597.8 (1)
1058.5 (1)
1181.8 (1)
90.0
F21IO4Te4
1912.5 (3)
992.5 (1)
985.6 (1)
90.0
C18H3 F5IN2
1173.0 (2)
1756.5 (2)
1059.7 (2)
90.0
C6H5F9ISb
556.4 (1)
2401.7 (6)
867.3 (2)
90.0
C6H5F2IO
833.37 (2)
1201.49 (4)
1603.48 (5)
69.183 (2)
81.145 (2)
70.602 (2)
1141.4 (1)
ꢀ80
b (pm)
c (pm)
a (pm)
b (pm)
90.0
96.39 (1)
90.0
92.65 (1)
90.0
105.90 (1)
90.0
g (pm)
90.0
748
V (106pm3)
I (8C)
1859 (4)
ꢀ100
2181 (5)
ꢀ120
1114.6 (4)
ꢀ80
ꢀ128
Space group
Z reflections
Measured
Independent
Parameters
Instrument
R1
P21cn(No33)
4
C2/c
4
P21/c
4
P21/c
4
P1
8
2954
8822
27349
6656
13260
3320
11731
2758
2342
8372
121
CAD4
0.019
133
CCD
342
CCD
171
CCD
422
CCD
0.026
0.031
0.035
0.031
wR2
0.048
0.061
0.054
0.058
0.059

S. Hoyer, K. Seppelt / Journal of Fluorine Chemistry 125 (2004) 989–996
995
PFA reaction vessel. With help of a glass vacuum line 5 ml
acetonitril are condensed in at ꢀ196 8C. The mixture is
warmed under stirring to ꢀ30 8C, and both solids dissolve.
After a short period a colorless precipitation occurs. Further
stirring for 1 h at ꢀ30 8C completes the reaction. The super-
natant solvent is removed, the crystalline solid is washed with
littleCH3CNat ꢀ30 8C, followed bydryinginhigh vacuumat
ꢀ30 8C. The colorless product is very sensitive against
moisture, and stays undecomposed at room temperature only
for minutes, due to loss of acetonitril from the lattice.
19F NMR (CD3CN, ꢀ25 8C). d ¼ 10 ppm, broad. Raman
spectrum (crystalline ꢀ40 8C, cmꢀ1): 3091 (vw), 3074 (vw),
3039 (vw), 2960 (w), 2931 (w), 2910 (vw), 2873 (vw), 2254
(w), 2110 (w), 1582 (vw), 1567 (vw), 1470 (w), 1427 (vw),
1370 (vw), 1263 (w), 1176 (vw), 1135 (w), 1096 (vw), 1045
(w), 1033 (vw), 1016 (w), 1004 (vw), 995 (w), 970 (w), 941
(w), 916 (vw), 904 (w), 830 (w), 818 (w), 784 (w), 660 (w),
609 (w), 570 (w), 552 (w), 503 (nsIF5) (s), 474 (w), 425 (w),
372 (m), 351 (w), 340 (w), 317 (w), 298 (w), 270 (w), 251
(m), 226 (w), 174 (w), 155 (w), 106 (vs).
730 (w), 657 (w), 653 (w), 605 (vw), 527 (w), 509 (w), 384
(vw), 330 (w), 319 (w), 299 (w), 264 (m), 254 (m), 216 (w),
140 (m).
Experimental details and results of the single crystal
structure determination see Tables 5 and 6.
3.7. Synthesis of FI(OTeF5)4
In the dry box 2 g (2.7 mmol) B(OTeF5)3 are weighed in a
PFA reaction vessel of 12 mm inner diameter, equipped with
a magnetic stirring bar. At the metal vacuum line 5 ml CFCl3
and 0.44 g (2 mmol) IF5 are condensed into the vessel at
ꢀ196 8C. The mixture is warmed under stirring to ꢀ20 8C,
gas evolution (BF3) sets in. The gas is occasionally pumped
off. After termination of the gassing all volatile materials are
pumped away between ꢀ40 and ꢀ20 8C. The colorless
product is crystallized from n–C4F9–SO2F. FTe(OTeF5)4
is moisture sensitive and decomposes slowly at room tem-
perature.
19F NMR (SO2ClF, ꢀ20 8C): ab4x spectrum, da ¼ ꢀ46:5,
db ¼ ꢀ35:5, dx ¼ 99:5 ppm, Jab ¼ 180 Hz, J125Te–Fb ¼
3696 Hz. Raman spectrum (crystalline ꢀ50 8C, cmꢀ1):
1439 (w), 1218 (m), 1209 (w), 952 (w), 923 (w), 824
(w), 709 (s), 672 (vs), 663 (s), 627 (m), 502 (m), 477
(m), 428 (vs), 323 (m), 307 (m), 261 (m), 251 (m), 235
(m), 202 (w), 164 (m), 129 (vs), 107 (m).
Suitable single crystals for the crystal structure determi-
nation are obtained from a solution in SO2ClF by cooling
from ꢀ20 to ꢀ78 8C. Experimental details and results of the
crystal structure determination see Tables 2 and 6.
Crystallographic data (excluding structure factors) for the
structures of the phenyliodine compounds have been depos-
ited with the Cambridge Crystallographic Data Centre as
supplementary publication nos. CCDC 216480 (C6H5IF4),
CCDC 214290 (pipþC6H5IF5ꢀ), CCDC 214289 (C6H5-
IF3þSbF6ꢀ), and CCDC 214291 (C6H5IOF2). Copies of
the data can be obtained, free of charge, on application to
CCDC, 12 Union Road, Cambridge CB2 1EZ, UK, (Fax:
(þ44)1223-336033 or E-mail: deposit@ccdc.com.ac.uk.)
The crystallographic data of FI(OTeF5)4 can be obtai-
ned from the Fachinformationszentrum Karlsruhe, 76344
Eggenstein-Leopoldshafen (Fax: (þ49)7247-808-666; E-
mail: crysdata@fiz-karlsruhe.de), by quoting the depository
number CSD 413244.
Single crystals are obtained from a CH3CN solution by
slow cooling from 10 to ꢀ35 8C. Results see Tables 3 and 6.
ꢀ
3.5. Synthesis of C6H5IF3þSbF6
In the dry box 140 mg (0.5 mol) C6H5IF4 are weighed into
a PFA reaction vessel of 6.5 mm inner diameter. 3 ml
anhydrous HF and 200 mg (0.9 mmol) SbF5 are condensed
into the vessel with help of a metal vacuum line at ꢀ196 8C.
The vessel is sealed and warmed to ꢀ30 8C under shaking.
Slow cooling to ꢀ80 8C affords colorless platelets of
C6H5IF3þSbF6ꢀ. Experimental details and results of the
single crystal structure determination are laid down in
Tables 4 and 6. Above ꢀ20 8C the compound turns blue,
finally black under decomposition.
19F NMR (SO2, ꢀ60 8C): d ¼ ꢀ39:9 (I–F), ꢀ111.4 (SbF,
broad). 1H NMR (SO2, ꢀ60 8C): d ¼ 7:116:83 ppm. Raman
(crystalline ꢀ100 8C cmꢀ1): 2973 (w), 2927 (w), 2877 (w),
1454 (w), 1095 (w), 1052 (w), 882 (m), 807 (w), 732 (s), 577
(s), 203 (w).
3.6. Synthesis of C6H5IOF2
3.5 mg (14.8 mol) C6H5IO2 are weighted into a 200 ml
PFA vessel [10]. 40% HF in H2O is added until the C6H5IO2
is completely dissolved at room temperature. The solution is
heated for 30 min to 60 8C, then cooled to room temperature,
then to 0 8C. Colorless needles are crystallizing out. The
supernatant solution is decanted, and the product is dried in
vacuum at 25 8C. The yield is essentially quantitative.
C6H5IOF2 is moisture sensitive, and decomposes at
224 8C under mild explosion. It is little (CH3CN) or not
soluble in organic solvents such as CH2Cl2, CFCl3.
Acknowledgements
This work has been supported by the Deutsche For-
schungsgemeinschaft and the Fonds der Chemischen Indus-
trie.
References
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1167 (vw), 1013 (m) (nIO), 992 (w), 821 (w), 787 (nsIF) (s),
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