Synthesis of Poly- And the First Perfluoroalkyl-N(SO2F)2 Derivatives: Improved Methods for the Preparation of XN(SO2F)2 (X = H, Cl) and Single-Crystal Diffraction Studies of HN(SO2Cl)2, HN(SO2F)2, and CF3CH2N(SO2F)2

Article abstract of DOI:10.1021/ic9800031

The preparation of HN(SO₂F)₂ was achieved conveniently by fluorination of HN(SO₂C1)₂ with SbF₃. Reactions of Hg[N(SO₂F)₂]₂ with fluoroalkyl iodides RI (R = i-C₃F₇CH₂CH₂ and CF₃CH₂) gave i-C₃F₇CH₂CH₂N(SO₂F) ₂ (1) and CF₃CH₂N(SO₂F)₂ (2). The chlorination of Hg[N(SO₂F)₂]₂ provided a high-yield method of synthesizing the well-known ClN(SO₂F)₂. N-alkylation of ClN(SO₂F)₂ with fluorinated ethenes CF₂=CHal₂ (CHal₂ = CF₂, CFCl, and CCl₂) resulted in the formation of CF₂ClCF₂N(SO₂F)₂ (3), CF₂ClCFClN(SO₂F)₂ (4a, major), CFCl₂-CF₂N(SO₂F)₂ (4b, minor), and CCl₃CF₂N(SO₂F)₂ (5). The synthesis of the first perfluoroalkyl-N(SO₂F)₂ derivatives CF₃N(SO₂F)₂ (6), C₂F₅N(SO₂F)₂ (7), n-C₃F₇N(SO₂F)₂ (8), and n-C₄F₉N(SO₂F)₂ (9) was accomplished with moderate-to-good yields by reacting ClN(SO₂F)₂ with iodoperfluoroalkanes R_FI (R_F = CF₃, C₂F₅, n-C₃F₇, and n-C₄F₉). Similarly, ClN(SO₂F)₂ reacted with CF₃CH₂I to give 2. Photolysis of ClN(SO₂F)₂ with iodoperfluoroalkanes R_FI (R_F = n-C₃F₇, and n-C₄F₉) gave 8 and 9 in low yields. HN(SO₂F)₂ belongs to a monoclinic crystal system P2₁ (No. 4): a = 5.1619(5) ?, b = 7.8153(8) ?, c = 6.8028(7) ?, β = 100.411(2)°, V= 269.92(5) ?³, Z= 2. HN(SO₂Cl)₂ is monoclinic P2₁/c (No. 14): a = 7.7331(3) ?, b = 10.0542(2) ?, c = 9.3197(3) ?, β = 109.495(1)°, V = 683.07(4) ?³, Z= 4. CF₃CH₂N(SO₂F)₂ is orthorhombic P2₁2₁2₁ (No. 19): a= 11.1245(1) ?, b = 28.8003(4) ?, c = 7.7120 ?, V = 2470.90(4) ?³, Z = 12.

Full text of DOI:10.1021/ic9800031

Inorg. Chem. 1998, 37, 6295-6303
6295
Synthesis of Poly- and the First Perfluoroalkyl-N(SO2F)2 Derivatives: Improved Methods
for the Preparation of XN(SO2F)2 (X ) H, Cl) and Single-Crystal Diffraction Studies of
†
HN(SO2Cl)2, HN(SO2F)2, and CF3CH2N(SO2F)2
Burkhard Krumm, Ashwani Vij, Robert L. Kirchmeier,* and Jean’ne M. Shreeve*
Department of Chemistry, University of Idaho, Moscow, Idaho 83844-2343
ReceiVed January 2, 1998
The preparation of HN(SO2F)2 was achieved conveniently by fluorination of HN(SO2Cl)2 with SbF3. Reactions
of Hg[N(SO2F)2]2 with fluoroalkyl iodides RI (R ) i-C3F7CH2CH2 and CF3CH2) gave i-C3F7CH2CH2N(SO2F)2
(1) and CF3CH2N(SO2F)2 (2). The chlorination of Hg[N(SO2F)2]2 provided a high-yield method of synthesizing
the well-known ClN(SO2F)2. N-alkylation of ClN(SO2F)2 with fluorinated ethenes CF2dCHal2 (CHal2 ) CF2,
CFCl, and CCl2) resulted in the formation of CF2ClCF2N(SO2F)2 (3), CF2ClCFClN(SO2F)2 (4a, major), CFCl2-
CF2N(SO2F)2 (4b, minor), and CCl3CF2N(SO2F)2 (5). The synthesis of the first perfluoroalkyl-N(SO2F)2 derivatives
CF3N(SO2F)2 (6), C2F5N(SO2F)2 (7), n-C3F7N(SO2F)2 (8), and n-C4F9N(SO2F)2 (9) was accomplished with
moderate-to-good yields by reacting ClN(SO2F)2 with iodoperfluoroalkanes RFI (RF ) CF3, C2F5, n-C3F7, and
n-C4F9). Similarly, ClN(SO2F)2 reacted with CF3CH2I to give 2. Photolysis of ClN(SO2F)2 with iodoperfluo-
roalkanes RFI (RF ) n-C3F7, and n-C4F9) gave 8 and 9 in low yields. HN(SO2F)2 belongs to a monoclinic crystal
system P21 (No. 4): a ) 5.1619(5) Å, b ) 7.8153(8) Å, c ) 6.8028(7) Å, â ) 100.411(2)°, V ) 269.92(5) Å3,
Z ) 2. HN(SO2Cl)2 is monoclinic P21/c (No. 14): a ) 7.7331(3) Å, b ) 10.0542(2) Å, c ) 9.3197(3) Å, â )
109.495(1)°, V ) 683.07(4) Å3, Z ) 4. CF3CH2N(SO2F)2 is orthorhombic P212121 (No. 19): a ) 11.1245(1) Å,
b ) 28.8003(4) Å, c ) 7.7120 Å, V ) 2470.90(4) Å3, Z ) 12.
Introduction
N-chloro derivatives with olefins.9-11 To the best of our
knowledge, the only report of a perfluoroalkyl derivative of HN-
(SO2F)2 or HN(SO2CF3)2 is the detection of CF3N(SO2CF3)2
as a volatile byproduct formed during the decomposition of Xe-
[N(SO2CF3)2]2.12,13
The chemistry of the strong nitrogen acids HN(SO2F)2 and
HN(SO2CF3)2 has been reviewed. These acids and their
derivatives have gained much attention because of important
applications, for example, as electrolytes, as additives for
electrolytes in fuel cells, or as selective electrophilic fluorinating
agents.1
The present work describes an extension of the chemistry of
ClN(SO2F)2, fluoroalkylation of Hg[N(SO2F)2]2, and the syn-
thesis and isolation of the first perfluoroalkyl-N(SO2F)2 deriva-
tives. In addition to the synthetic studies, we have also carried
out single-crystal X-ray diffraction studies on low-melting HN-
(SO2Cl)2, HN(SO2F)2, and CF3CH2N(SO2F)2. Moreover, we
report a much improved route for the preparation of HN(SO2F)2.
In addition to the usual methods of characterization, the 14N
NMR shifts of these materials were determined. The only
previously reported nitrogen NMR data are the 15N shifts for
several 15N enriched xenon-containing N(SO2F)2 species such
More recent reports deal with some new N(SO2F)2 deriva-
tives, such as R3EN(SO2F)2 (E ) Si,2,3 Ge,3 Sn,3,4 Pb3; R )
alkyl), [Ph3C][N(SO2F)2],5 [Ph3PH][N(SO2F)2],3 and their crystal
structures. The crystal structure of CsN(SO2F)2 was determined
independently by two groups.3,6 Also syntheses of an azido
derivative, N3N(SO2F)2,7 and the crystal structure of S[N-
8
(SO2F)2]2 were reported.
Alkyl and fluoroalkyl derivatives of HN(SO2F)2 and HN(SO2-
CF3)2 were prepared by the reaction of either the acids or their
as Xe[N(SO2F)2]2,14 [XeN(SO2F)2]+[Sb3F16-],15 FXeN-
17
(SO2F)2,16-18 HN(SO2CF3)2, and [N(SO2F)2]2
.
With the
† Presented at the 15th International Symposium on Fluorine Chemistry,
Vancouver, B.C., Canada, 1997; Abstr. Nos. RFS C-2, P2-177.
(1) Vij, A.; Kirchmeier, R. L.; Shreeve, J. M.; Verma, R. D. Coord. Chem.
ReV. 1997, 158, 413 and references therein.
(2) Trehan, A.; Vij, A.; Walia, M.; Kaur, G.; Verma, R. D.; Trehan, S.
Tetrahedron Lett. 1993, 34, 7335.
exception of FN(SO2F)219 and ClN(SO2F)2,20 the IR spectra of
(11) Vij, A.; Zheng, Y. Y.; Kirchmeier, R. L.; Shreeve, J. M. Inorg. Chem.
1994, 33, 3281.
(12) Foropoulos, J., Jr.; DesMarteau, D. D. Inorg. Chem. 1984, 23, 3720.
(13) Foropoulos, J., Jr.; DesMarteau, D. D. J. Am. Chem. Soc. 1982, 104,
4260.
(3) Hiemisch, O.; Henschel, D.; Blaschette, A.; Jones, P. G. Z. Anorg.
Allg. Chem. 1997, 623, 324.
(4) Vij, A.; Singh, S.; Verma, R. D. J. Fluorine Chem. 1992, 58, 43.
(5) Hiemisch, O.; Henschel, D.; Jones, P. G.; Blaschette, A. Z. Anorg.
Allg. Chem. 1996, 622, 829.
(6) Farrugia, L. J.; Holfter, H.; Klapo¨tke, T. M. J. Fluorine Chem. 1996,
78, 51.
(14) Schumacher, G. A.; Schrobilgen, G. J. Inorg. Chem. 1983, 22, 2178.
(15) Faggiani, R.; Kennepohl, D. K.; Lock, C. J. L.; Schrobilgen, G. J.
Inorg. Chem. 1986, 25, 563.
(16) DesMarteau, D. D.; LeBlond, R. D.; Hossain, S. F.; Nothe, D. J. Am.
Chem. Soc. 1981, 103, 7734.
(7) Holfter, H.; Klapo¨tke, T. M.; Schulz, A. Polyhedron 1996, 15, 1405.
(8) Hass, A.; Klare, Ch.; Betz, P.; Bruckmann, J.; Kru¨ger, C.; Tsay, Y.-
H.; Aubke, F. Inorg. Chem. 1996, 35, 1918.
(9) Varwig, J.; Mews, R.; Glemser, O. Chem. Ber. 1974, 107, 2468.
(10) Colburn, C. B.; Hill, W. E.; Verma, R. D. J. Fluorine Chem. 1981,
17, 75.
(17) Swayer, J. F.; Schrobilgen, G. J.; Sutherland, S. J. Inorg. Chem. 1982,
21, 4064.
(18) Swayer, J. F.; Schrobilgen, G. J.; Sutherland, S. J. J. Chem. Soc. Chem.
Commun. 1982, 210.
(19) Lustig, M.; Bumgardner, C. L.; Johnson, F. A.; Ruff, J. K. Inorg.
Chem. 1964, 3, 1165.
10.1021/ic9800031 CCC: $15.00 © 1998 American Chemical Society
Published on Web 11/06/1998

6296 Inorganic Chemistry, Vol. 37, No. 24, 1998
Krumm et al.
N(SO2F)2 derivatives in the gas phase have not been reported.
All of the IR spectra in this study were recorded in the gas
phase, including those for HN(SO2F)2 and [N(SO2F)2]2. Be-
cause of the stability of the N(SO2F)2• radical vis-a`-vis N(SO2-
The reaction of perhalogenated ethenes with ClN(SO2F)2 gave
the perhalogenoalkyl-N(SO2F)2 derivatives 3, 4a/4b, and 5
(Scheme 4). Interestingly for the reaction with CF2dCFCl, we
observed the formation of two isomers. The main product was
found to be isomer 4b, formed by attack of the N(SO2F)2 moiety
on the CFCl carbon atom. Because of the slightly lower vapor
pressure of 4b, it was possible to separate 4b from 4a by low-
temperature vacuum distillation as described in the Experimental
Section.
•
CF3)2 , we have been successful in carrying out photolytic
reactions of ClN(SO2F)2 with some perfluoroalkyl iodides to
generate some N-perfluoroalkyl bis(fluorosulfonyl)imide deriva-
tives. ClN(SO2CF3)2 is known to decompose under photolytic
conditions to form [CF3SO2NSO2]2 and CF3Cl, but ClN(SO2F)2
forms [N(SO2F)2]2 and Cl2 exclusively.
Scheme 4
Results and Discussion
Previously, the synthesis of the starting material, HN(SO2F)2,
was best achieved by fluorination of HN(SO2Cl)221 with AsF3.22
However, separation problems due to the presence of HSO3F
made the isolation of HN(SO2F)2 difficult and resulted in only
about 52% isolated yields. A modification to the procedure
for separating HSO3Cl from HN(SO2Cl)2 and subsequent
fluorination and removal of traces (<5%) of HSO3F using KCl
monitored by 19F NMR spectroscopy resulted in pure HN-
(SO2F)2 in yields as high as ∼92%.23
Fluorination of HN(SO2Cl)2 with SbF3 has been reported
recently, but no detailed procedure is listed.3 We found that
SbF3 was superior to AsF3 for the fluorination of HN(SO2Cl)2.
It replaced the relatively expensive AsF3, which also has higher
toxicity. Another important aspect is the fact that we never
observed the formation of HSO3F as a byproduct. SbF3 was
utilized in slight excess at room temperature as shown in Scheme
1. HN(SO2F)2 was isolated in good yields.
The reaction of ClN(SO2F)2 with iodoperfluoroalkanes pro-
vided a route to the first perfluoroalkyl-N(SO2F)2 derivatives
(Scheme 5). Derivative 2 can be synthesized in better yields
than by the method described in Scheme 3 by reaction of ClN-
(SO2F)2 with CF3CH2I.
Scheme 5
Scheme 1
24
The mercury salt Hg[N(SO2F)2]2 proved to be a useful
intermediate. For example, ClN(SO2F)2 was prepared from Hg-
[N(SO2F)2]2 (Scheme 2) in higher yield than that from the silver
salt AgN(SO2F)2, which gave only moderate yields of ClN-
(SO2F)2.20
Chlorine and iodine were identified as byproducts. We
believe that this reaction proceeded via a radical mechanism.
The reaction of ClN(SO2F)2 with CF3Br under identical condi-
tions did not produce 6. Instead, we observed the formation of
ClSO2F, which indicates fragmentation of ClN(SO2F)2. No
other decomposition products were isolated or identified.
Photolysis of mixtures of ClN(SO2F)2 and RFI also produced
the perfluoroalkyl-N(SO2F)2 derivatives but only in low yields
(Scheme 6).
Scheme 2
Alkylation of Hg[N(SO2F)2]2 with polyfluoroalkyl iodides
(Scheme 3) at elevated temperatures led to the respective
polyfluoroalkyl-N(SO2F)2 derivatives 1 and 2. The less reactive
polyfluoroalkyl iodides required more vigorous conditions than
those described for the reactions of the nonfluorinated iodides
CH3I and C2H5I with AgN(SO2F)2 (2 h/25 °C).25
Scheme 6
The 19F NMR spectra of compounds 3, 4a, and 6-9 showed
two resonances for the SF fluorine atoms. This phenomenon
was also observed for CF3CFClCF2N(SO2F)2 and (CF3)2CClN-
(SO2F)2.9 We believe that this is due to a staggered conforma-
tion of the SO2F groups in the N(SO2F)2 moiety which resulted
in inequivalence of the SF fluorine atoms. Variable-temperature
experiments in the range of 25-60 °C with 8 showed that
increasing the temperature to 60 °C did not affect this inequiva-
lence. Derivatives 1, 2, and 5 showed a single resonance for
the SF fluorine atoms that is the same as that observed for CH3-
CF2N(SO2F)2, CH2ClCF2N(SO2F)2, and CH3CH2CH(CH3)N-
Scheme 3
(20) Ruff, J. K. Inorg. Chem. 1966, 5, 732.
(21) Becke-Goehring, M.; Fluck, E. Inorg. Synth. 1966, 8, 105.
(22) Ruff, J. K.; Lustig, M. Inorg. Synth. 1968, 11, 138.
(23) Vij, A. Ph.D. Dissertation, Panjab University, India, 1991; Chapter 7.
(24) Singh, S.; DesMarteau, D. D. Inorg. Chem. 1986, 25, 4596.
(25) Ruff, J. K. Inorg. Chem. 1965, 4, 1446.

Synthesis of Poly- and Per(fluoroalkyl)N(SO2F)2
Inorganic Chemistry, Vol. 37, No. 24, 1998 6297
Table 1. Crystallographic Data for HN(SO2X)2 (X ) F or Cl) and
CF3CH2N(SO2F)2
HN(SO2Cl)2
HN(SO2F)2 CF3CH2N(SO2F)2
empirical formula
formula weight
temperature (°C)
crystal system
space group
a (Å)
HCl2NO4S2
214.04
-60(2)
monoclinic
HF2NO4S2
181.14
-100(2)
monoclinic
C2H2F5NO4S2
263.17
-60(2)
orthorhombic
P212121 (No. 19)
11.1245(1)
28.8003(4)
7.7120(0)
90
P21/c (No. 14) P21 (No. 4)
7.7331(3)
10.0542(2)
9.3197(3)
109.495(1)
683.07(4), 4
2.081
5.1619(5)
7.8153(8)
6.8028(7)
100.411(2)
269.92(5), 2
2.229
b (Å)
c (Å)
â (deg)
volume( Å3), Z
2470.90(4), 12
2.122
7.26
F
calcd (g cm-3
)
µ (cm-1
F(000)
)
15.05
424
9.76
180
1560
θ range for data (deg) 2.79-28.25
3.04-28.20
1.96-28.24
Figure 1. Molecular structure of HN(SO2Cl)2 with thermal ellipsoids
at 30% probability
limiting indices
-8 e h e 10 -6 e h e 6
-14 e h e 14
-13 e k e 11 -7 e k e 10 -38 e k e 31
-12 e l e 11 -9 e l e 8
-9 e l e 10
14723, 5783
Table 2. Atomic Coordinates (×104) and Equivalent Isotropic
Displacement Parameters (Å2 × 103) and Bond Lengths and Angles
reflections
collected/unique
Rint
8015, 1614
1750, 886
a
0.0295
0.041
886/0/87
0.0257
5783/0/404
for HN(SO2Cl)2
data/restraints/
1614/0/87
a. Atomic Coordinates and Equivalent Isotropic
Displacement Parameters
parameters
goodness of fit on F2 1.113
1.082
1.097
R1, wR2 [2σ(I) data]a 0.0368, 0.0880 0.0256, 0.0674 0.0386, 0.0903
x
y
z
U(eq)
R1, wR2 [all data]a
extinction coefficient 0.011(2)
0.0427, 0.0917 0.0263, 0.0676 0.0468, 0.0942
0.079(11)
0.302
0.0041(3)
0.350
Cl(1)
Cl(2)
S(1)
-2092(1)
4007(1)
-788(1)
3097(1)
-1684(3)
-474(3)
4334(3)
2652(3)
1195(3)
8721(1)
5900(1)
6985(1)
7703(1)
6152(3)
6596(2)
8259(2)
8365(2)
7399(3)
681(1)
1754(1)
1100(1)
2019(1)
1844(3)
-252(2)
3369(2)
593(2)
70(1)
45(1)
35(1)
30(1)
59(1)
43(1)
43(1)
40(1)
37(1)
largest diff. peak
(e Å-3
largest diff. hole
(e Å-3
0.454
)
-0.359
-0.354
-0.309
S(2)
)
O(1)
O(2)
O(3)
O(4)
N(1)
a w ) 1/[σ2(Fo ) + (0.0417P)2 + 0.6062P], where P ) (Fo2 + 2Fc2)/
2
3.
2372(3)
(SO2F)2,10 suggesting an eclipsed conformation of the SO2F
groups. For 3, we observed the presence of both conformers
in the 19F NMR spectrum in a ratio of 11:1 (staggered/eclipsed)
and were able to assign the resonances (see the Experimental
Section).
b. Bond Lengths and Angles
bond
length (Å)
bond
length (Å)
Cl(1)-S(1)
Cl(2)-S(2)
S(1)-O(1)
S(1)-O(2)
S(1)-N(1)
1.9880(11)
1.9894(9)
1.408(2)
1.415(2)
1.649(2)
S(2)-O(3)
S(2)-O(4)
S(2)-N(1)
N(1)-H(1)
1.417(2)
1.422(2)
1.639(2)
0.78(4)
The 14N NMR spectra of compounds 1-9 measured in CDCl3
showed broad resonances (line widths of 350-700 Hz) in the
range of -200 to -250 ppm relative to nitromethane. These
shifts and line widths lie in the range typical for nitrogen
resonances having sulfonamide structures.26
Although HN(SO2Cl)2 and its derivatives have been known
for over 3 decades, no structures with the N(SO2Cl)2 moiety
have been reported.27 There has been a recent increase in
interest in the structures of compounds containing the N(SO2X)2
moiety.3,5,6,8,28 The modifications we have made to the synthetic
procedure for the preparation of HN(SO2F)2 afford this acid,
as well as its fluorinated analogue in high purity. The
availability of diffraction quality crystals formed at low tem-
peratures for these acids and CF3CH2N(SO2F)2 provided an
opportunity to study the cryogenic crystal and molecular
structures of these compounds. All of the crystallographic data
are listed in Table 1.
bond
angle (deg)
bond
angle (deg)
108.75(12)
O(1)-S(1)-O(2)
O(1)-S(1)-N(1)
O(2)-S(1)-N(1)
122.18(14) O(4)-S(2)-N(1)
106.77(13) O(3)-S(2)-Cl(2) 107.93(10)
108.38(12) O(4)-S(2)-Cl(2) 107.22(9)
O(1)-S(1)-Cl(1) 108.57(12) N(1)-S(2)-Cl(2) 103.49(9)
O(2)-S(1)-Cl(1) 107.11(10) S(2)-N(1)-S(1)
N(1)-S(1)-Cl(1) 102.04(10) S(2)-N(1)-H(1)
125.75(14)
117(3)
117(3)
O(3)-S(2)-O(4)
O(3)-S(2)-N(1)
121.74(12) S(1)-N(1)-H(1)
106.26(12)
a U(eq) is defined as one-third of the trace of the orthogonalized Uij
tensor.
S-NH-S arrangement is planar because of the delocalization
of the nitrogen lone pair over the O-S-N-S-O π framework
(average angle around nitrogen ≈120°). The point group for
the molecule is C2. A crystallographic C2 axis along the H-N
bond bisects the S-N-S bond. The chlorine atoms are located
on opposite sides of the S-N-S plane, similar to the positions
of the trifluoromethyl groups in the CF3-containing analogue.
The S-N and S-O bond distances in HN(SO2Cl)2 are com-
parable to those reported in HN(SO2CF3)2,8 but the S-N-S
angles are compressed to 125.7(2)° from the value of 128.4-
(2)° found in the latter case.
The molecular structure of HN(SO2Cl)2 is shown in Figure
1. The atomic coordinates, equivalent isotropic displacement
parameters, bond lengths, and bond angles for HN(SO2Cl)2 are
given in Table 2. As found in other nitrogen acids,8,29-31 the
(26) Mason, J. Nitrogen. In Multinuclear NMR; Mason, J., Ed.; Plenum
Press: New York, 1987; Chapter 12, p 350.
(27) Cambridge Structural Database System; Cambridge Crystallographic
Data Center, April 1997.
(28) Vij, A. Crystal and molecular structures of AgN(SO2CF3)2(H2O)L [L
) C6H6, C6H5CH3, and C6H4(1,2-CH3)2]. Unpublished results.
(29) Cotton, F. A.; Stokely, P. F. J. Am. Chem. Soc. 1970, 92, 294.
(30) Blaschette, A.; Wieland, E.; Schomburg, D.; Adelhelm, M. Z. Anorg.
Allg. Chem. 1986, 533, 7.
(31) DesMarteau, D. D.; Zuberi, S. S.; Pennington, W. T.; Randolph, B.
B. Eur. J. Solid State Inorg. Chem. 1992, 29, 777.

6298 Inorganic Chemistry, Vol. 37, No. 24, 1998
Krumm et al.
Figure 2. Molecular structure of HN(SO2F)2 with thermal ellipsoids
at 50% probability.
Figure 3. Intermolecular forked H‚‚‚O bonding shown in the crystal
packing diagram of HN(SO2Cl)2 viewed down the b axis.
Table 3. Atomic Coordinates (×104) and Equivalent Isotropic
Displacement Parameters (Å2 × 103) and Bond Lengths and Angles
a
for HN(SO2F)2
a. Atomic Coordinates and Equivalent Isotropic
Displacement Parameters
x
y
z
U(eq)
S(1)
S(2)
F(1)
F(2)
O(1)
O(2)
O(3)
O(4)
N(1)
6835(1)
7766(1)
7295(4)
5704(4)
8018(4)
4158(3)
6415(5)
9960(5)
8596(5)
677(1)
-2064(1)
-459(3)
-1369(3)
2263(4)
8961(1)
6336(1)
10830(3)
4617(3)
9507(3)
8090(3)
7456(4)
5522(4)
7551(4)
21(1)
25(1)
36(1)
43(1)
34(1)
30(1)
40(1)
43(1)
24(1)
489(3)
-3147(3)
-2587(4)
-288(3)
b. Bond Lengths and Angles
bond
length (Å)
bond
length (Å)
S(1)-O(1)
S(1)-O(2)
S(1)-F(1)
S(1)-N(1)
S(2)-O(3)
1.402(3)
1.409(2)
1.534(2)
1.621(3)
1.405(2)
S(2)-O(4)
S(2)-F(2)
S(2)-N(1)
N(1)-H(1)
1.408(2)
1.532(2)
1.633(3)
0.64(6)
Figure 4. Intermolecular chain-type H‚‚‚O bonding shown in the
crystal packing diagram of HN(SO2F)2 viewed down the a axis.
Intermolecular hydrogen bonding in nitrogen acids is known
bond
angle (deg)
bond
angle (deg)
107.48(14)
to occur in different fashions. These range from a linear N‚‚
O(1)-S(1)-O(2) 123.4(2)
O(1)-S(1)-F(1)
O(2)-S(1)-F(1)
O(4)-S(2)-F(2)
29
‚H bond resulting in chain formation as seen in HN(SO2C6H5)2
(O‚‚‚H ) 2.854(6) Å) to dimeric units in HN(SO2C2H5)2
107.29(13) O(3)-S(2)-N(1) 110.36(13)
106.33(13) O(4)-S(2)-N(1) 106.8(2)
30
O(1)-S(1)-N(1) 107.70(13) F(2)-S(2)-N(1)
O(2)-S(1)-N(1) 108.36(13) S(1)-N(1)-S(2)
99.64(13)
124.8(2)
(O‚‚‚H ) 2.87 Å). Recently, a bifurcated hydrogen bond has
been observed in the crystal lattice of HN(SO2CF3)2 (O‚‚‚H
≈2.26 Å), where the N-H interacts with the two oxygen atoms
of the SO2 groups located on the neighboring molecule. The
packing diagram of HN(SO2Cl)2 along the b axis is shown in
Figure 3. In this case, the hydrogen-bonding networks form
six-membered rings arranged in a polymeric fashion. The N-H
interacts with two oxygen atoms of a neighboring molecule in
a bifurcated manner, as seen in HN(SO2CF3)2, with N1-H1‚‚
‚O2a ) 2.51(4) Å and N1-H1‚‚‚O4a ) 2.23(4) Å (a ) x, 3/2 -
y, 1/2 + z). The corresponding N1‚‚‚O2a and N1‚‚‚O4a contact
distances are 3.082(3) and 2.935(3) Å, respectively. In the case
of crystal packing of HN(SO2F)2, the intermolecular hydrogen
bonding is chain-type with only one hydrogen bond linking the
N-H proton to the sulfonyl oxygen of the neighboring molecule
(Figure 4): N1-H1‚‚‚O2b ) 2.25(6) Å; N1‚‚‚O2b ) 2.892(3)
Å (b ) 1 + x, y, z). This observation suggests that bifurcated
intermolecular hydrogen bonding is not unique to nitrogen acids
where a strong electron-withdrawing group is bonded to the
sulfur atom. A comparison of intermolecular hydrogen bond
F(1)-S(1)-N(1)
101.66(12) S(1)-N(1)-H(1) 117(6)
O(3)-S(2)-O(4) 123.5(2)
S(2)-N(1)-H(1) 114(6)
O(3)-S(2)-F(2)
106.5(2)
a U(eq) is defined as one-third of the trace of the orthogonalized Uij
tensor.
HN(SO2F)2 crystallizes in a polar space group P21, and
refinement of Flack’s parameter gives a value of 0.02(12), which
suggests that the assigned absolute configuration is accurate.
The fluorine atoms are in a staggered conformation (Figure 2),
imparting to the molecule approximate C2 symmetry. Table
3b contains the bond lengths and angles for HN(SO2F)2.
Substitution of the chlorine atoms in HN(SO2Cl)2 by fluorine
causes shortening of both the S-O and the S-N bond distances
from 1.412(2) and 1.644(2) Å to 1.406(2) and 1.627(3) Å,
respectively. Consequently, the S-N-S angle is further
compressed from 125.8(1) in HN(SO2Cl)2 to 124.8(2)° in HN-
(SO2F)2. Compression of the S-N-S angle in HN(SO2X)2
follows the order X ) CF3 > Cl > F and can be explained on
the basis of decreasing steric crowding about the sulfur atoms.

Synthesis of Poly- and Per(fluoroalkyl)N(SO2F)2
Inorganic Chemistry, Vol. 37, No. 24, 1998 6299
Table 4. Atomic Coordinates (×104) and Equivalent Isotropic Displacement Parameters (Å2 × 103) and Bond Lengths and Angles for
a
CF3CH2N(SO2F)2
a. Atomic Coordinates and Equivalent Isotropic Displacement Parameters
x
y
z
U(eq)
x
y
z
U(eq)
S(1)
S(2)
S(3)
S(4)
S(5)
S(6)
F(1)
F(2)
F(3)
F(4)
F(5)
F(6)
F(7)
F(8)
F(9)
F(10)
F(11)
F(12)
F(13)
F(14)
F(15)
-1 294(1)
1 277(1)
3 596(1)
6 160(1)
8 552(1)
11 126(1)
-1 501(2)
1 363(2)
-1 098(2)
806(2)
192(1)
154(1)
3 056(1)
3 183(1)
6 667(1)
6 834(1)
11 833(1)
11 811(1)
4 123(3)
1 392(3)
7 280(3)
7 412(3)
8 209(3)
8 478(3)
5 685(3)
1 716(3)
2 597(3)
2 473(3)
10 807(3)
13 557(3)
7 645(3)
7 520(3)
6 746(3)
33(1)
33(1)
34(1)
36(1)
31(1)
32(1)
53(1)
54(1)
59(1)
57(1)
68(1)
62(1)
60(1)
70(1)
61(1)
64(1)
50(1)
59(1)
66(1)
66(1)
73(1)
O(1)
O(2)
O(3)
O(4)
O(5)
O(6)
O(7)
O(8)
O(9)
O(10)
O(11)
O(12)
N(1)
N(2)
N(3)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
-1 088(2)
-2 193(2)
1 128(2)
2 202(2)
2 653(2)
3 772(2)
5 954(2)
7 042(2)
7 617(2)
8 734(2)
12 051(2)
11 010(2)
-7(2)
46(1)
511(1)
-327(1)
341(1)
1348(1)
2016(1)
1636(1)
1140(1)
2127(1)
1713(1)
2033(1)
1374(1)
379(1)
1293(1)
2041(1)
744(1)
542(1)
923(1)
1115(1)
2416(1)
2218(1)
1 348(3)
3 519(3)
2 909(3)
4 195(3)
5 691(4)
6 884(3)
8 505(4)
6 405(4)
11 271(3)
13 570(3)
10 805(4)
12 195(3)
3 901(3)
5 992(3)
11 023(3)
5 249(4)
7 047(4)
4 670(4)
2 850(4)
9 699(4)
7 888(4)
50(1)
48(1)
45(1)
50(1)
57(1)
53(1)
67(1)
49(1)
41(1)
48(1)
58(1)
43(1)
27(1)
29(1)
27(1)
28(1)
37(1)
27(1)
36(1)
28(1)
38(1)
1537(1)
1468(1)
1837(1)
1846(1)
-249(1)
380(1)
302(1)
254(1)
885(1)
1333(1)
1896(1)
768(1)
1338(1)
1414(1)
1382(1)
2102(1)
1971(1)
1935(1)
2560(1)
-72(3)
3 497(2)
6 417(2)
4 877(3)
5 961(2)
4 058(2)
8 444(2)
11 165(2)
8 762(2)
10 668(2)
9 773(3)
4 862(2)
9 835(2)
-15(3)
-96(3)
4 833(3)
4 931(3)
9 828(3)
9 758(3)
b. Bond Lengths and Angles
bond
length (Å)
bond
length (Å)
bond
length (Å)
bond
length (Å)
S(1)-O(1)
S(1)-O(2)
S(1)-F(1)
S(1)-N(1)
S(2)-O(4)
S(2)-O(3)
S(2)-F(2)
1.402(2)
1.403(2)
1.531(2)
1.663(2)
1.400(2)
1.409(2)
1.530(2)
S(4)-F(7)
S(4)-N(2)
S(5)-O(10)
S(5)-O(9)
S(5)-F(11)
S(5)-N(3)
S(6)-O(12)
1.545(2)
1.662(2)
1.402(2)
1.403(2)
1.536(2)
1.665(2)
1.396(2)
S(2)-N(1)
S(3)-O(5)
S(3)-O(6)
S(3)-F(6)
S(3)-N(2)
S(4)-O(7)
S(4)-O(8)
1.664(2)
1.402(2)
1.403(2)
1.520(2)
1.658(2)
1.396(3)
1.401(2)
S(6)-O(11)
S(6)-F(12)
S(6)-N(3)
N(1)-C(1)
N(2)-C(3)
N(3)-C(5)
1.397(2)
1.536(2)
1.658(2)
1.478(4)
1.475(4)
1.486(4)
bond
angle (deg)
bond
angle (deg)
bond
angle (deg)
bond
angle (deg)
O(1)-S(1)-O(2)
O(1)-S(1)-F(1)
O(2)-S(1)-F(1)
O(1)-S(1)-N(1)
O(2)-S(1)-N(1)
F(1)-S(1)-N(1)
O(4)-S(2)-O(3)
123.6(2)
O(10)-S(5)-O(9)
O(12)-S(6)-O(11)
C(1)-N(1)-S(1)
C(1)-N(1)-S(2)
S(1)-N(1)-S(2)
C(3)-N(2)-S(3)
C(3)-N(2)-S(4)
123.7(2)
124.1(2)
120.0(2)
121.1(2)
118.8(2)
120.3(2)
120.5(2)
O(4)-S(2)-F(2)
O(3)-S(2)-F(2)
O(4)-S(2)-N(1)
O(3)-S(2)-N(1)
F(2)-S(2)-N(1)
O(5)-S(3)-O(6)
O(7)-S(4)-O(8)
107.1(2)
S(3)-N(2)-S(4)
C(5)-N(3)-S(6)
C(5)-N(3)-S(5)
S(6)-N(3)-S(5)
N(1)-C(1)-C(2)
N(2)-C(3)-C(4)
N(3)-C(5)-C(6)
119.1(2)
120.2(2)
120.6(2)
119.06(14)
111.9(2)
112.0(2)
111.2(2)
106.26(14)
107.36(14)
108.92(14)
107.61(13)
100.79(12)
123.3(2)
106.85(14)
107.14(13)
109.38(13)
100.80(13)
123.4(2)
124.5(2)
a U(eq) is defined as one-third of the trace of the orthogonalized Uij tensor.
distances suggests that the relative acidity in HN(SO2X)2
increases in the order X ) CF3 ≈ F > Cl > C2H5 ≈ C6H5.
A variety of new per- and polyfluoroalkyl derivatives of
N(SO2F)2 are reported in this study. However, with the
exception of the low melting CF3CH2N(SO2F)2, all of these
derivatives are liquids. Only one other alkyl derivative, CH2-
[N(SO2F)2]2,32 has been studied using single-crystal X-ray
diffraction.
The unit cell shows three crystallographically independent
molecules for 2. Selected bond lengths and angles are listed in
Table 4. The molecular structure of CF3CH2N(SO2F)2 (2),
shown in Figure 5, contains a planar sp2-hybridized nitrogen
atom with the alkyl chain lying in a plane perpendicular to the
plane containing the S-N-S bond. This is consistent with the
torsion angles: S1-N1-C1-C2 ) 89.9(3)°, S2-N1-C1-C2
Figure 5. Molecular structure of CF3CH2N(SO2F)2 with thermal
) -91.0(3)°, S3-N2-C3-C4 ) 90.6(3)°, S4-N2-C3-C4
) -89.9(3)°, S6-N3-C5-C6 ) 95.3(3)°, S5-N3-C5-C6
) -89.0(3)°.
The average C-N bond length of 1.479(4) Å in 2 is similar
to that found in CH3N(SO2CH3)2 at room temperature (1.479
ellipsoids at 30% probability.
Å)33 and at -95 °C (1.484 Å),34 in CH2[N(SO2F)2]2 (1.486 Å),32
and in [CH3NSO2]3 (1.487 Å)35 but significantly shorter than
the corresponding distances found in C6H5CH2CH2N(SO2C6H4-
(32) Zak, Z.; Ruzicka, A. Z. Anorg. Allg. Chem. 1987, 549, 67.
(33) Schomburg, D.; Blaschette, A.; Wieland, E. Z. Naturforsch., B: Chem.
Sci. 1986, 41, 1112.
(34) Blaschette, A.; Naveke, M.; Jones, P. G. Z. Naturforsch., B: Chem.
Sci. 1991, 46, 46.
(35) Hazell, A. C. Acta Crystallogr. 1974, B30, 2724.

6300 Inorganic Chemistry, Vol. 37, No. 24, 1998
Krumm et al.
Table 5. Comparative Structural Characteristics of Some Derivatives Containing the O-S-N-S-O π-framework
av bond lengths (Å)
av bond angles (deg)
compound
S-O
S-N
S-F
S-N-S
O-S-O
a
HN(SO2Cl)2
1.412(2)
1.409(2)
1.406(2)
1.402(2)
1.402(5)
1.378(4)
1.405(3)
1.375
1.407(8)
1.415(3)
1.421(3)
1.418(6)
1.419(2)
1.414(3)
1.644(2)
1.644(1)
1.627(3)
1.662(2)
1.658(5)
1.688(4)
1.626(3)
1.69
1.571(6)
1.567(3)
1.577(3)
1.593(6)
1.563(2)
1.561(3)
125.8(1)
128.4(2)
124.8(2)
119.0(2)
119.8(4)
118.4(2)
120.5(2)
123.6
120.1(7)
121.4(2)
121.2(2)
119.3(4)
120.8(1)
122.0(2)
122.2(1)
123.9(1)
123.5(2)
123.8(2)
123.1(3)
123.2(4)
123.3
125.5
112.2(12)
110.3
119.7(2)
120.0(4)
118.6(9)
119.1(2)
8
HN(SO2CF3)2
a
HN(SO2F)2
1.533(2)
1.533(2)
1.525(5)
1.502(5)
1.532(3)
a
CF3CH2N(SO2F)2
CH2[N(SO2F)2]2
S[N(SO2F)2]2
32
8
17
FXeN(SO2F)2
-
15
[XeN(SO2F)2+][Sb3F16
]
53,b
AgN(SO2F)2‚C6H6
1.403(10)
1.574(3)
1.566(2)
1.555(5)
1.566(2)
1.565(2)
43
(C6H5)4AsN(SO2F)2
3
CsN(SO2F)2
3
(CH3)3PbN(SO2F)2
(C6H5)3PHN(SO2F)2
(C6H5)3CHN(SO2F)2 5
5
a Present work. b The oxygen and fluorine atoms in the N(SO2F)2 group are disordered.
NO2-p)2 (1.508 Å)36 and C6H5CH2N(SO2C6H11)(SO2C6H4Br-
p) (1.512 Å).37 However, the C-N distance of 1.342 Å found
in CH3N(SO3K)238 is very short compared to those of the other
compounds listed above. The S-N bond shows a concomitant
increase in length as the C-N bond length decreases. For
example, in CH3N(SO3K)2,38 the S-N bond length is 1.750 Å,
compared to 1.665 Å observed in the case of C6H5CH2N-
(SO2C6H11)(SO2C6H4Br-p). The S-N bond distance value of
1.662(2) Å compares well with the corresponding value of
1.658(5) Å found in CH2[N(SO2F)2]2.
R-N(SO2F)2 derivatives. For the ionic analogues, this bond
distance is ∼1.56 Å.
The effects of these structural changes can be seen in fluorine
NMR and infrared spectroscopic data for both ionic and covalent
R-N(SO2F)2 compounds. For example, the νasSO frequency
2
for the covalent derivatives10,20 (see the Experimental Section)
is observed at ∼1500 cm-1, which is ∼100 cm-1 higher than
that observed for ionic derivatives such as CsN(SO2F)2 (1380
cm-1).25 A short S-F bond in covalently bonded R-N(SO2F)2
compounds is consistent with a deshielded fluorine nucleus,
based on the decrease in S-F bond polarity expected for the
covalent derivatives. Consequently, covalent R-N(SO2F)2
compounds10,20 show a S-F resonance ∼+60 ppm in the 19F
NMR spectrum whereas the ionic counterparts resonate at ∼+52
ppm.25 Compounds that exhibit intermediate S-F chemical
shifts are compounds that contain a highly polarized N(SO2F)2
moiety.4
A comparison of the structural parameters of N(SO2F)2-
containing derivatives (Table 5) shows that with an increase in
the covalent nature of the R-N(SO2F)2 bond the S-O and S-F
bond lengths are shortened and the S-N bonds are elongated.
- 39
In the case of H3N+SO3
,
the S-N bond length of 1.772 Å
corresponds to a S-N single bond. The S-N bond distances
of 1.627(3) Å in HN(SO2F)2 [almost identical to the S-N bond
distance of 1.626(3) Å in FXeN(SO2F)2],17 1.662(2) Å in CF3-
The O-S-O bond angles also show an increase in going
from ionic to covalent bonding. As seen from Table 5, the
O-S-O bond angle in (C6H5)4AsN(SO2F)246 of 110.3° is close
to tetrahedral. However, in a covalent molecule like CF3CH2N-
(SO2F)2, this O-S-O angle increases to 123.8(2)°. In the case
of a cationic species such as [XeN(SO2F)2]+,15 the O-S-O
value reaches a very high value of 125.5°. This effect is
consistent with the order of bond-pair-bond-pair repulsion
between the S-O bonds possessing considerable double bond
character, which is expected to be at a maximum for the [XeN-
(SO2F)2]+ species.
Perhaps the most interesting features of the crystal structure
of CF3CH2N(SO2F)2 are the intra- and intermolecular hydrogen
bonding networks. These interactions are listed in Table 6 and
shown in Figure 6. Within the same asymmetric unit, the
molecule containing the atom C5 shows only intramolecular
bonds with the sulfonyl oxygen atoms O9 and O11 at 2.52(3)
and 2.33(4) Å, respectively. However, the other two crystal-
lographically independent molecules that are present are linked
via bifurcated intermolecular hydrogen bonds, forming a four-
membered center. This type of bifurcated hydrogen bonding
originating from an alkyl proton has recently been reported by
Gard et al.47 Figure 7 shows intermolecular hydrogen-bonding
networks resulting from the interaction of the molecules from
different unit cells. These distances range from 2.43(3) to 2.89-
8
CH2N(SO2F)2, and 1.688(4) Å in S[N(SO2F)2]2 indicate a
decrease in the contribution of the nitrogen lone pair to N-S
dative bonding, thereby indicating an increase in the S-N bond
order.
In covalent R-N(SO2F)2 derivatives, the S-O bond distances
lie in the range 1.375-1.405 Å, which is close to the S-O
bond length found in SO2F2 (1.405 Å), where the S-O bond
order is assigned as 2.0 by Gillespie et al.40 These S-O
distances are, however, shorter than the corresponding bond
lengths found in CsN(SO2F)2 [1.421(3) Å],3,6 (C6H5)3XN(SO2F)2
[X ) C, 1.414(3) Å; X ) P, 1.419(2) Å],5 Me3PbN(SO2F)2
[1.418(6) Å],3 NH2(SO3)- (1.457 Å),41,42 NH(SO3)2 [1.449
2-
Å],43,44 and N(SO3)33- (1.468 Å).45 An increase in S-O bond
order is observed in going from an ionic to a covalently bonded
R-N(SO2F)2 derivative. A similar trend is also observed for
the S-F bond lengths, which fall around 1.53 Å for the covalent
(36) Curtis, V. A.; Pavkovik, S. F. Acta Crystallogr. 1983, C39, 1077.
(37) Higgins, T.; Bruke, P. O.; Spillane, W. J.; Cunningham, P. D.;
McArdle, P. Acta Crystallogr. 1989, C45, 685.
(38) Morris, A. J.; Kennard, C. H. L.; Hall, J. P.; Smith, G. Inorg. Chim.
Acta 1982, 62, 247.
(39) Bats, J. W.; Coppens, P.; Koetzle, Acta Crystallogr. 1977, B33, 37.
(40) Gillespie, R. J.; Robinson, E. A. Can. J. Chem. 1963, 41, 2047.
(41) Cox, G. W.; Sabine, T. M.; Padmanabhan, Ban, N. T.; Chung, M. K.;
Surjadi, A. S. Acta Crystallogr. 1967, 23, 578.
(42) Jeffery, G. J.; Stadler, J. J. Chem. Soc. A 1951, 1467.
(43) Jeffery, G. J.; Jones, D. W. Acta Crystallogr. 1956, 9, 238.
(44) Hodgson, P. G.; Moore, F. H.; Kennard, C. H. L. J. Chem. Soc., Dalton
Trans. 1976, 1443.
(46) Isenberg, W.; Noltemayer, M.; Sheldrick, G. M. Acta Crystallogr.
1982, B38, 2887.
(47) Braden, D. A.; Gard, G. L.; Weakly, T. J. R. Inorg. Chem. 1996, 35,
(45) Tillack, J. V.; Kennard, C. H. L. J. Chem. Soc. A 1970, 1637.
1912.

Synthesis of Poly- and Per(fluoroalkyl)N(SO2F)2
Inorganic Chemistry, Vol. 37, No. 24, 1998 6301
Table 6. Intra- and Intermolecular Hydrogen Bond Distances in
CF3CH2N(SO2F)2
Intramolecular Interactions
bond
distance (Å)
C1-H1A‚‚‚O4
C1-H1B‚‚‚O2
C3-H3A‚‚‚O8
C3-H3B‚‚‚O4
C3-H3A‚‚‚O5
C5-H5A‚‚‚O11
C5-H5B‚‚‚O9
2.49(2)
2.28(3)
2.46(2)
2.34(3)
2.32(3)
2.33(4)
2.52(3)
Intermolecular Interactions
bond
distance (Å)
symmetry operation
Figure 7. Packing diagram of CF3CH2N(SO2F)2 viewed along the b
axis showing the intermolecular H‚‚‚O contacts.
O1‚‚‚H3A
O2‚‚‚H3A
O3‚‚‚H3A
O6‚‚‚H5B
O7‚‚‚H5A
O8‚‚‚H1B
O9‚‚‚H5A
O10‚‚‚H1B
O11‚‚‚H5B
O12‚‚‚H1A
2.60(3)
2.89(3)
2.65(3)
2.77(3)
2.50(4)
2.67(3)
2.43(4)
2.50(3)
2.70(3)
2.68(3)
1/2 - x, -y, -1/2 + z
-1 + x, y, z
1/2 - x, -y, -1/2 + z
-1/2 + x, 1/2 - y, 2 - z
-1/2 + x, 1/2 - y, 2 - z
1 + x, y, z
Laboratorium, Go¨ttingen, Germany. Photolysis reactions were carried
out in quartz reaction vessels irradiated in a Rayonet photochemical
reactor with 3000-Å UV lamps.
-1/2 + x, 1/2 - y, 2 - z
1 + x, y, 1 + z
The X-ray diffraction data were collected on a Siemens SMART
3-circle diffractometer (ø axis fixed at 54.74°) equipped with a CCD
detector maintained near -54 °C. The frame data were acquired with
the SMART48 software with a Siemens 3-circle platform using graphite-
monochromated Mo KR radiation (λ ) 0.710 73 Å). Because HN-
(SO2X)2 (X ) Cl or F) and CF3CH2N(SO2F)2 are low-melting
compounds, in addition to being highly moisture-sensitive, a single
colorless crystal of each was mounted in a glass capillary fixed on a
copper pin premounted on a goniometer head and then transferred onto
the diffractometer platform under a stream of cold nitrogen. The cell
constants were determined from 60 10-s frames. A complete hemi-
sphere of data was scanned on ω (0.3°) with a run time of 10 s/frame
at a detector resolution of 512 × 512 pixels. A total of 1271 frames
were collected in three sets, and a final set of 50 frames, identical to
the first 50 frames, were also collected to determine crystal decay. The
frames were then processed on a SGI-Indy/IndigoII workstation by
using SAINT software49 to give the hkl file corrected for Lorentz
polarization. The data were corrected for absorption using the
SADABS50 program. The structures were solved by the direct method
using the SHELX-9051 program and refined by least-squares method
on F2 using SHELXTL version 5.03.52 All non-hydrogen atoms were
refined anisotropically. The hydrogen atoms were located from the
difference electron density maps and refined isotropically. The crystal
used for the diffraction study showed no decomposition during data
collection.
Preparation of HN(SO2F)2 by Fluorination of HN(SO2Cl)2 with
SbF3. Freshly sublimed SbF3 (0.472 mol) was added in three portions
to 0.506 mol of HN(SO2Cl)2 under an atmosphere of dry nitrogen in a
250-mL, round-bottomed flask equipped with a reflux condenser. After
a few minutes, the mixture liquified and was slightly exothermic. After
ca. 30 min, the reaction temperature returned to 25 °C, and the mixture
was stirred for a total of 4 h. The resulting slurry was distilled
repeatedly (five times) at 25 °C/0.01 Torr to ensure complete removal
of SbCl3 which sublimed slowly along with HN(SO2F)2. The receiver
flask was cooled with N2 (l). The liquid HN(SO2F)2 was separated
from small amounts of solid SbCl3, by removal of the liquid with a
glass pipet. The yield of pure HN(SO2F)2 obtained by this process
was 70%. The 1H and 19F NMR data agreed with the literature values.25
1/2 + x, 1/2 - y, 2 - z
1 + x, y, 1 + z
Figure 6. Intramolecular hydrogen bonding in CF3CH2N(SO2F)2
forming four-membered H2O2 units.
(3) Å as seen in Table 6. In addition to these intermolecular
hydrogen bonds, there are numerous other fluorine-fluorine
contacts at a distance of ∼2.9 Å.
Studies involving the chemistry of these per- and polyfluo-
roalkyl-N(SO2F)2 derivatives are continuing.
Experimental Section
21
24
Materials. HN(SO2Cl)2 and Hg[N(SO2F)2]2 were prepared by
the literature methods. SbF3 (Ozark-Mahoning, Tulsa, OK) was
sublimed in a vacuum prior to use.
General Considerations. A conventional vacuum system, consist-
ing of a Pyrex glass vacuum line fitted with Teflon needle stopcocks
and equipped with Heise Bourdon tube and Televac thermocouple
gauges, was used to handle gases and volatile liquids. Standard
pressure-volume-temperature techniques were used to quantitate
starting materials or products. Fractional condensation (trap-to-trap
distillation) was used for the purification of products. Infrared spectra
were recorded on a Perkin-Elmer 1710 FT-IR spectrometer with a 10-
cm glass cell equipped with AgCl windows. 1H, 13C, 14N, and 19F NMR
spectra were obtained on a Bruker AC200 or AC300 FT-NMR
instrument using CDCl3 as solvent at room temperature unless otherwise
noted. Chemical shifts were reported with respect to (CH3)4Si, CH3-
NO2, or CFCl3. Mass spectra were obtained with a Varian VG 7070
HS mass spectrometer by using the electron-impact (EI) technique. Peak
assignments of chlorine-containing fragments were based on 35Cl.
Elemental analyses were performed by Beller Mikroanalytisches
(48) SMART, Software for the CCD Detector System, version 4.043;
Siemens Analytical Instruments Division: Madison, WI, 1995.
(49) SAINT, Software for the CCD Detector System, version 4.035; Siemens
Analytical Instruments Division: Madison, WI, 1995.
(50) SADABS, Siemens Area Detector Absorption Correction Program;
Siemens Analytical Instruments Division: Madison, WI, 1995.
(51) Sheldrick, G. M. SHELXS-90, Program for the Solution of Crystal
Structure; University of Go¨ttingen: Go¨ttingen, Germany, 1990.
(52) SHELXTL 5.03, Program Library for Structure Solution and Molecular
Graphics; Siemens Analytical Instruments Division: Madison, WI,
1995.
(53) Begley, M. J.; Sowerby, D. B.; Verma, R. D.; Vij, A. J. Organomet.
Chem. 1994, 481, 243.

6302 Inorganic Chemistry, Vol. 37, No. 24, 1998
Krumm et al.
In addition to the 14N NMR shift, we list the IR spectrum in the gas
phase. The liquid-phase spectrum has been reported previously.25
The mixture of 4a/4b, (2.5:1), obtained from the reaction of ClN-
(SO2F)2 with CF2dCFCl, was distilled repeatedly through -40 °C traps.
The major isomer, according to the 19F NMR spectrum, is retained at
-40 °C, but the minor isomer is more volatile and slowly passed this
trap. Analysis of the 19F NMR spectrum of the purified, less volatile
isomer was consistent with the structure of 4a and displayed a more
complicated NMR spectrum, because of the asymmetric CFClN carbon
center. For the minor isomer 4b, which could only be obtained in
60% purity, only NMR data are given.
HN(SO2F)2: IR (gas) 3419 m (νNH), 1495 s (νasSO), 1321 m, 1224
m (νsSO), 992 w, 912 m (νSN), 888 w, 837 m (νSF), 568 m cm-1 14N
;
NMR δ -241 [δ -182 HN(SO2Cl)2; -231 Hg[N(SO2F)2]2 (CD3CN)].
[N(SO2F)2]2: prepared according to ref 20; IR (gas) 1509 s/1491 m
(νasSO), 1246 s (νsSO), 921 m (νSN), 867 m, 847 s (νSF), 797 w (νNN),
603 m, 577 s, 463 m cm-1
.
Preparation of ClN(SO2F)2 by Chlorination of Hg[N(SO2F)2]2.
Chlorine (67 mmol) was condensed into a 160-mL, stainless-steel vessel
which contained 28 mmol of Hg[N(SO2F)2]2. The contents were kept
at 25 °C for 5 days. Distillation through traps cooled to -20 and -80
°C gave ClN(SO2F)2 in 89% yield in the -80 °C trap.
Alkylation of Hg[N(SO2F)2]2 with RI (R ) i-C3F7CH2CH2 and
CF3CH2). To 2 mmol of Hg[N(SO2F)2]2 loaded in a 80-mL stainless-
steel vessel was condensed 6 mmol of alkyl iodide. For R ) i-C3F7-
CH2CH2, the vessel was kept at 70 °C for 12 h whereas for R ) CF3CH2
the vessel was kept at 120 °C for 48 h. Distillation of the respective
contents through traps at -30 °C [i-C3F7CH2CH2N(SO2F)2 (1) retained]
and at -60 °C [CF3CH2N(SO2F)2 (2) retained] removed the excess
alkyl iodides. The yields were 64% 1 (colorless liquid) and 33% 2
[large colorless rectangular crystals (mp 35-36 °C)].
Spectral data for CF2ClCFClN(SO2F)2 (4a): IR (gas) 1462 m/1424
s (νasSO), 1234 s (νsSO), 1192 m, 1151 m, 1087 m, 1006 m, 943 w, 874
m, 846 m, 561 m cm-1 19F NMR δ [61.1 (d, 4JF-F ) 7.4 Hz)/60.9 (d,
;
4JF-F ) 7.4 Hz)/60.3 (dd)/59.2 (t, 4JF-F ) 7.3 Hz)/58.5 (dt)] (SF, 2F),
-70.09/-70.11 (CF2Cl, d, 2F, 3JF-F ) 5.9/6.3 Hz), -75.4/-81.9 (CF,
m, 1F); 13C NMR δ 121.1 (CF2Cl, dt, 1JC-F ) 302.4 Hz, 2JC-F ) 33.7
Hz)/118.1 (CF2Cl, dt, 1JC-F ) 300.0 Hz, 2JC-F ) 34.1 Hz), 118.3 (CFCl,
td, 1JC-F ) 311.1 Hz, 2JC-F ) 39.3 Hz)/118.1 (CFCl, td, 1JC-F ) 311.5
Hz, 2JC-F ) 39.1 Hz)/111.4 (CFCl, td, 1JC-F ) 341.1 Hz, 2JC-F ) 35.9
Hz); 14N NMR δ -242; MS (EI) [m/e (species, intensity)] 296 (M+
-
Cl, 1), 246 (M+ - CF2Cl, 1), 194 (CF2CClNSO2F+, 2), 164 (N(SOF)-
SO2F+, 45), 151 (CF2ClCFCl/CFCl2CF2+, 100), 101 (CFCl2+, 35), 85
(CF2Cl+, 28), 83 (SO2F+, 17), 67 (SOF+, 39). Anal. Calcd for C2-
Cl2F5NO4S2: C, 7.23; Cl, 21.35. Found: C, 7.40; Cl, 21.08.
Spectral data for i-C3F7CH2CH2N(SO2F)2 (1): IR (gas) 1496
s/1467 m (νasSO), 1332 m, 1297 m, 1269 m, 1233 s (νsSO), 1173 m,
Spectral data for CFCl2CF2N(SO2F)2 (4b): 19F NMR δ 65.8 (SF,
d m, 2F, 5JF-F ) 14.5 Hz), -63.3 (CFFN, AB system of dt, 1F, 2JF-F
) 168.4 Hz, 3JF-F ) 6.9 Hz, 4JF-F ) 2.3 Hz), -64.4 (CFFN, AB system
1123 m, 1089 m, 954 w, 896 m, 845 m, 827 m, 796 w, 573 m cm-1
;
19F NMR δ 58.9 (SF, t, 2F, 4JF-H ) 1.0 Hz), -77.0 (CF3, d, 6F, 3JF-F
) 6.4 Hz), -186.5 (CF, m, 1F); 1H NMR δ 4.25 (CH2N, m, 2H), 2.64
(CFCH2, m, 2H); 13C{1H} NMR δ 120.4 (CF3, qd, 1JC-F ) 286.9 Hz,
2
3
4
of dt, 1F, JF-F ) 168.1 Hz, JF-F ) 5.2 Hz, JF-F ) 1.7 Hz), -91.2
(CF, t of +,s, 1F); 13C NMR δ 123.3 (CF2N, dt, JC-F ) 304.9 Hz,
1
2JC-F ) 36.7 Hz), 112.3 (CFCl2, dt, JC-F ) 282.8 Hz, JC-F ) 38.7
1
2
1
2
2JC-F ) 27.2 Hz), 90.0 (CF, dsept, JC-F ) 206.2 Hz, JC-F ) 33.3
Hz).
3
2
Hz), 47.5 (CH2N, d, JC-F ) 6.7 Hz), 28.1 (CH2CF, d, JC-F ) 20.1
Spectral data for CCl3CF2N(SO2F)2 (5): IR (gas) 1502 s/1480 m
(νasSO), 1247 m (νsSO), 1172 m, 1046 w, 983 m, 908 w, 839 m, 607 w,
Hz); 14N NMR δ -236; MS (EI) [m/e (species, intensity)] 358 (M+
-
F, 67), 256 (M+ - 2F - SO2F, 31), 197 [(CF3)2CFCH2CH2+, 19], 194
[CH2N(SO2F)2+, 100], 177 [(CF3)2CCHCH2+, 5], 128 (CFNSO2F+, 4),
114 (CF3CFCH2+, 6), 93 (C3F3+, 10). Anal. Calcd for C5H4F9NO4S2:
C, 15.92; H, 1.07. Found: C, 16.39; H, 1.19.
571 m cm-1
;
19F NMR δ 69.1 (SF, t, 2F, 4JF-F ) 2.2 Hz), -61.4 (CF2,
t, 2F); 13C NMR δ 125.9 (CF2, t, JC-F ) 305.2 Hz), 96.1 (CCl3, t,
2JC-F ) 37.3 Hz); 14N NMR δ -202; MS (EI) [m/e (species, intensity)]
312 (M+ - Cl, 24), 262 (M+ - Cl - CF2, 52), 194 (CClCF2NSO2F+,
6), 144 (CClNSO2F+, 39), 101 (CFCl2+, 35), 85 (CF2Cl+, 70), 83
(SO2F+, 100), 67 (SOF+, 18). Anal. Calcd for C2Cl3F4NO4S2: C, 6.89;
Cl, 30.51. Found: C, 7.34; Cl, 30.49.
1
Spectral data for CF3CH2N(SO2F)2 (2): IR (gas) 3044 w, 3001 w,
1499 s/1474 m (νasSO), 1430 m, 1401 m, 1337 m, 1285 m, 1235 s (νsSO),
1188 s, 1123 m, 997 s, 921 w, 830 s, 739 w, 665 m, 607 m, 575 s, 470
m cm-1 19F NMR δ 59.2 (SF, qt, 2F, 5JF-F ) 3.7 Hz, 4JF-H ) 1.5 Hz),
;
3 1
Alkylation of ClN(SO2F)2 with RFI (RF ) CF3, C2F5, n-C3F7,
n-C4F9, CF3CH2). Mixtures consisting of 6 mmol of ClN(SO2F)2 and
11 mmol iodoperfluoroalkane or CF3CH2I were kept in 80-mL,
stainless-steel vessels at 60 °C for 4 days. Distillation of the contents
through traps at -20 and -90 °C [CF3N(SO2F)2 (6)], -80 °C [C2F5N-
(SO2F)2 (7) or n-C3F7N(SO2F)2 (8)], and -60 °C [n-C4F9N(SO2F)2 (9
or 2)] retained the products as mixtures with iodine. Removal of iodine
was achieved by keeping the mixtures over fresh mercury until complete
decolorization. Yields of the products as pure colorless liquids are
87% 6, 43% 7, 29% 8, 23% 9, and 45% 2.
Photolysis of ClN(SO2F)2 with RFI (RF ) n-C3F7, n-C4F9).
Mixtures consisting of 4 mmol of ClN(SO2F)2 and 9 mmol of RFI were
photolyzed in a 300-mL, quartz vessel for 24 h at 3000 Å. Distillation
of the contents through traps at -20 and -80 °C (8) or -60 °C (9)
gave the products as mixtures with iodine. After the mixtures were
kept over fresh mercury until complete decolorization, 8 (15%) and 9
(14%) were obtained in pure form.
-71.4 (CF3, tt, 3F, JF-H ) 7.5 Hz); H NMR δ 4.52 (CH2, tq, 2H);
13C{1H} NMR δ 121.6 (CF3, q, 1JC-F ) 279.9 Hz), 52.4 (CH2, q, 2JC-F
) 38.5 Hz); 14N NMR δ -238; MS (EI) [m/e (species, intensity)] 244
(M+ - F, 18), 223 (M+ - 2HF, 4), 194 [CH2N(SO2F)2+, 100], 179
(CF3CHNSO2F+, 5), 110 (CHNSO2F+, 8), 92 (CH2NSO2+, 19), 86
(SOF2+, 19), 83 (SO2F+/CF3CH2+, 5), 69 (CF3+, 7), 67 (SOF+, 5). Anal.
Calcd for C2H2F5NO4S2: C, 9.13; H, 0.77. Found: C, 9.38; H, 0.86.
Alkylation of ClN(SO2F)2 with Ethenes CF2dCHal2 (CHal2 )
CF2, CFCl, and CCl2). Mixtures consisting of 3 mmol of ClN(SO2F)2
and 6 mmol of ethene were kept in 80-mL stainless-steel vessels at 25
°C for 3 days. Distillation of the contents through traps at -50 °C
[CF2ClCF2N(SO2F)]2 (3) (60%); CF2ClCFClN(SO2F)2/CFCl2CF2N-
(SO2F)2 mixture (4a/4b) (78%)] and -30 °C [(CCl3CF2N(SO2F)2 (5)
(46%)] gave the products as colorless liquids.
Spectral data for CF2ClCF2N(SO2F)2 (3): IR (gas) 1510 m/1464
s/1428 s (νasSO), 1329 m, 1238 s (νsSO), 1192 m, 1151 m, 1096 s, 977
s, 882 m, 861 m, 840 m, 821 m, 771 m, 726 w, 658 w, 574 m, 564 m
Spectral data for CF3N(SO2F)2 (6): IR (gas) 1465 s/1430 s (νasSO),
1303 s, 1277 s, 1236 s (νsSO), 1122 vs, 973 s, 876 m, 836 m, 811 m,
cm-1 19F NMR (two conformers 11:1) major (staggered) δ 61.0 (SF,
;
741 w, 694 w, 600 m, 578 m, 549 m cm-1 19F NMR δ 61.1 (SF, d,
;
d, 1F, 4JF-F ) 7.3 Hz), 59.1 (SF, dt, 1F, 4JF-F ) 10.8 Hz, 5JF-F ) 7.0
1F, 4JF-F ) 7.3 Hz), 56.5 (SF, m, 1F), -53.5 (CF3, d, 3F, 4JF-F ) 6.2
Hz); 13C NMR δ 118.5 (CF3, q, 1JC-F ) 281.1 Hz); 14N NMR δ -246;
MS (EI) [m/e (species, intensity)] 249 (M+, 1), 164 [N(SOF)SO2F+,
5], 83 (SO2F+, 4), 69 (CF3+, 100), 67 (SOF+, 7). Anal. Calcd for
CF5NO4S2: N, 5.62. Found: N, 5.65.
Hz), -73.2 (CF2Cl, t, 2F, 3JF-F ) 1.7 Hz), -83.6 (CFFN, AB system
2
4
of dm, 1F, JF-F ) 125.8 Hz, JF-F ) 6.5 Hz), -84.7 (CFFN, AB
4
system of dm, 1F, JF-F ) 11.1 Hz), minor (eclipsed) δ 65.2 (SF, tt,
4
5
2F, JF-F ) 7.6 Hz, JF-F ) 2.2 Hz), -69.2 (CF2Cl, m, 2F), -85.5
(CF2N, tm, 2F, JF-F ) 7.6 Hz); 13C NMR δ 118.6 (CF2, tt, JC-F
)
)
4
1
301.5 Hz, 2JC-F ) 38.5 Hz), 116.3 (CF2, tt, 1JC-F ) 300.4 Hz, 2JC-F
Spectral data for CF3CF2N(SO2F)2 (7): IR (gas) 1465 s/1430 s
(νasSO), 1391 w, 1254 vs, 1237 s (νsSO), 1155 s, 1066 s, 976 w, 910 m,
883 m, 863 m, 824 m, 788 m, 742 m, 722 m, 588 w, 568 m, 468 w
38.9 Hz); 14N NMR δ -239; MS (EI) [m/e (species, intensity)] 296
(M+ - F, 7), 280 (M+ - Cl, 34), 230 (M+ - CF2Cl, 91), 164 [N(SOF)-
SO2F+, 21], 142 [N(SO2)2+, 45], 135 (CF2ClCF2+, 67), 128 (CFNSO2F+,
100), 100 (CF2CF2+, 5), 97 (NSO2F+, 4), 85 (CF2Cl+, 39), 83 (SO2F+,
26), 67 (SOF+, 13). Anal. Calcd for C2ClF6NO4S2: C, 7.61; F, 36.12.
Found: C, 7.57; F, 36.0.
4
cm-1
;
19F NMR δ 61.1 (SF, d, 1F, JF-F ) 7.6 Hz), 59.5 (SF, m, 1F),
-85.3 (CF3, t, 3F, 3JF-F ) 1.9 Hz), -85.4 (CFFN, AB system of dm,
1F, 2JF-F ) 130.8 Hz, 4JF-F ) 10.1 Hz), -86.5 (CFFN, AB system of
dm, 1F); 13C NMR δ 115.0 (CF3, qt, JC-F ) 286.7 Hz, JC-F ) 38.4
1
2

Synthesis of Poly- and Per(fluoroalkyl)N(SO2F)2
Inorganic Chemistry, Vol. 37, No. 24, 1998 6303
1
2
Hz), 114.7 (CF2N, tq, 1JC-F ) 299.9 Hz, 2JC-F ) 46.1 Hz); 14N NMR
NMR δ 116.8 (CF3, qt, JC-F ) 288.4 Hz, JC-F ) 32.4 Hz), 116.5
δ -241; MS (EI) [m/e (species, intensity)] 299 (M+, 1), 230 (M+
-
1
2
(CF2N, tt, JC-F ) 302.1 Hz, JC-F ) 33.3 Hz), 107.9/107.7 (CCF2-
CF2C, m); 14N NMR δ -241; MS (EI) [m/e (species, intensity)] 278
(M+ - 2F - SO2F, 1), 230 (M+ - C3F7, 1), 219 (C4F9+, 40), 169
(C3F7+, 6), 164 [N(SOF)SO2F+, 63], 131 (C3F5+, 48), 119 (C2F5+, 21),
100 (C2F4+, 18), 83 (SO2F+, 11), 69 (CF3+, 100), 67 (SOF+, 26). Anal.
Calcd for C4F11NO4S2: C, 12.03; N, 3.51. Found: C, 12.17; N, 3.58.
CF3, 1), 164 [N(SOF)SO2F+, 9], 119 (C2F5+, 100), 83 (SO2F+, 7), 69
(CF3+, 26), 67 (SOF+, 13). Anal. Calcd for C2F7NO4S2: N, 4.68.
Found: N, 4.59.
Spectral data for n-CF3CF2CF2N(SO2F)2 (8): IR (gas) 1465 s/1430
s (νasSO), 1356 w, 1333 m, 1248 vs, 1237 s (νsSO), 1161 s, 1099 s, 996
s, 856 m, 822 m, 778 m, 747 m, 720 m, 687 w, 660 w, 564 s, 536 m,
464 w, 403 w cm-1
;
19F NMR δ 61.1 (SF, d, 1F, 4JF-F ) 7.3 Hz), 59.8
Acknowledgment. We are grateful for the support of British
Nuclear Fuels plc and NSF EPSCoR (OSR-9350539). Dr. Gary
Knerr is thanked for obtaining the mass spectral data as well as
for help with the NMR experiments. The single-crystal SMART
CCD X-ray diffraction facility at the University of Idaho was
established with the NSF-Idaho EPSCoR program under NSF
OSR-9350539 and M. J. Murdock Charitable Trust, Vancouver,
WA.
2
(SF, m, 1F), -80.9 (CFFN, AB system of m, 1F, JF-F ) 134.9 Hz),
4
-81.0 (CF3, t, 3F, JF-F ) 7.2 Hz), -82.3 (CFFN, AB system of m,
1F), -128.6 (CF2, s, 2F); 13C NMR δ 116.5 (CF3, qt, JC-F ) 288.4
1
2
1
2
Hz, JC-F ) 33.0 Hz), 116.3 (CF2N, tt, JC-F ) 301.6 Hz, JC-F
)
33.7 Hz), 106.1 (CCF2C, m); 14N NMR δ -243; MS (EI) [m/e (species,
intensity)] 349 (M+, 1), 230 (M+ - C2F5, 4), 228 (M+ - 2F - SO2F,
4), 169 (C3F7+, 100), 169 (C3F7+, 6), 164 [N(SOF)SO2F+, 41], 119
(C2F5+, 12), 100 (C2F4+, 6), 83 (SO2F+, 8), 69 (CF3+, 71), 67 (SOF+,
15). Anal. Calcd for C3F9NO4S2: C, 10.32; N, 4.01. Found: C, 9.89;
N, 4.08.
Supporting Information Available: For HN(SO2Cl)2, HN(SO2F)2,
and CF3CH2N(SO2F)2: tables listing full data collection and processing
parameters, bond lengths and angles, atomic coordinates, equivalent
isotropic and anisotropic displacement coefficients, and hydrogen atom
coordinates and isotropic displacement coefficients (21 pages). Order-
ing information is given on any current masthead page.
Spectral data for n-CF3CF2CF2CF2N(SO2F)2 (9): IR (gas) 1465
s/1430 s (νasSO), 1305 m, 1256 vs, 1238 s (νsSO), 1154 m, 1134 m,
1106 w, 1076 s, 957 m, 933 m, 917 m, 884 m, 858 m, 821 m, 774 w,
743 m, 688 w, 561 m, 465 w cm-1 19F NMR δ 61.1 (SF, d, 1F, 4JF-F
;
) 7.6 Hz), 59.8 (SF, m, 1F), -80.0 (CFFN, AB system of m, 1F,
2JF-F ) 133.8 Hz), -80.9 (CF3, t, 3F, 4JF-F ) 8.9 Hz), -81.3 (CFFN,
AB system of m, 1F), -125.1 (CF2, m, 2F), -126.4 (CF2, m, 2F); 13
C
IC9800031