Hydrogen bonding in the anhydrous 1:1 proton-transfer compounds of isonipecotamide with nitro-substituted benzoic acids: The salts of the three isomeric mononitrobenzoic acids and of 3,5-dinitro-benzoic acid

Article abstract of DOI:10.1107/S0108270110045750

The structures of the anhydrous 1:1 proton-transfer com-pounds of isonipecotamide (piperidine-4-carboxamide) with the three isomeric mononitro-substituted benzoic acids and with 3,5-dinitro-benzoic acid, namely 4-carbamoylpiperidinium 2-nitro-benzoate, (I), 4-carbamoylpiperidinium 3-nitrobenz-oate, (II), and 4-carbamoylpiperidinium 4-nitrobenzoate, (III), all C₆H₁₃N₂O⁺·C₇H ₄NO₄^-, and 4-carbamoylpiperidin-ium 3,5-dinitro-benzoate, C₆H₁₃N₂O₈ ⁺·C₇H₃N₂O₆ ^-, (IV), respectively, have been determined at 200 K. All the salts form hydrogen-bonded structures, viz. three-dimensional in (I), two-dimensional in (II) and (III), and one-dimensional in (IV). Featured in the hydrogen bonding of three of these [(I), (II) and (IV)] is the cyclic head-to-head amide-amide homodimer motif [graph set R₂ ²(8)] through a duplex N - H...O association, the dimer then giving structure extension via either piperidinium or amide H-atom donors and carboxylate O-atom and, in some examples [(II) and (IV)], nitro O-atom acceptors. In (I), the centrosymmetric amide-amide homodimers are expanded laterally through N - H...O hydrogen bonds via cyclic R₄ ²(8) inter-actions, forming ribbons which extend along the c cell direction. These ribbons incorporate the 2-nitro-benzoate cations through centrosymmetric cyclic piperidine-carboxylate N - H...O associations [graph set R₄ ⁴(12)], giving inter-connected sheets in the three-dimensional structure. In (II), in which no amide-amide homodimer is present, duplex piperidinium-amide N - H...O homomolecular hydrogen-bonding associations [graph set R₂ ²(14)] give centrosymmetric head-to-tail dimers. Structure extension occurs through hydrogen-bonding associations between both the amide H-atom donors and carboxylate and nitro O-atom acceptors, as well as a three-centre piperidinium-carboxylate N - H...O,O′ cyclic R₁ ²(4) association, giving the two-dimensional network structure. In (III), the centrosymmetric amide-amide dimers are linked through the two carboxylate O-atom acceptors of the anions via bridging piperidinium N - H...O,O′...H - Namide hydrogen bonds, giving the two-dimensional sheet structure which features centrosymmetric cyclic R₄ ⁴(12) associations. In (IV), the amide-amide dimer is also centrosymmetric, with the dimers linked to the anions through amide-nitro N - H...O inter-actions. The piperidin-ium groups extend the structure into one-dimensional ribbons via N - H..._Ocarboxylate hydrogen bonds. The structures reported here further demonstrate the utility of the isonipecotamide cation in mol-ecular assembly. They also highlight the efficacy of the cyclic R₂²(8) amide-amide hydrogen-bonding homodimer motif in this process and provide an additional homodimer motif type in the head-to-tail R₂²(14) association.

Full text of DOI:10.1107/S0108270110045750

organic compounds
Acta Crystallographica Section C
Crystal Structure
Communications
the centrosymmetric amide–amide dimers are linked through
the two carboxylate O-atom acceptors of the anions via
bridging piperidinium N—Hꢀ ꢀ ꢀO,O0ꢀ ꢀ ꢀH—Namide hydrogen
bonds, giving the two-dimensional sheet structure which
features centrosymmetric cyclic R44(12) associations. In (IV),
the amide–amide dimer is also centrosymmetric, with the
dimers linked to the anions through amide–nitro N—Hꢀ ꢀ ꢀO
interactions. The piperidinium groups extend the structure
into one-dimensional ribbons via N—Hꢀ ꢀ ꢀOcarboxylate
hydrogen bonds. The structures reported here further
demonstrate the utility of the isonipecotamide cation in
molecular assembly. They also highlight the efficacy of the
cyclic R22(8) amide–amide hydrogen-bonding homodimer
motif in this process and provide an additional homodimer
motif type in the head-to-tail R22(14) association.
ISSN 0108-2701
Hydrogen bonding in the anhydrous
1:1 proton-transfer compounds of
isonipecotamide with nitro-substituted
benzoic acids: the salts of the three
isomeric mononitrobenzoic acids and
of 3,5-dinitrobenzoic acid
Graham Smith* and Urs D. Wermuth
Comment
Faculty of Science and Technology, Queensland University of Technology, GPO
Box 2434, Brisbane, Queensland 4001, Australia
The alicyclic amide piperidine-4-carboxamide (isonipecota-
mide, INIPA) (O’Neil, 2001) or any of its compounds
previously had no structural representation in the crystal-
lographic literature, prompting our investigation of the
possible use of this Lewis base for the formation of crystalline
proton-transfer compounds with organic acids. We have
recently reported the crystal structures and hydrogen-bonding
features of the anhydrous 1:1 salts with both picric acid and
3,5-dinitrosalicylic acid (two polymorphs, both picrates)
(Smith & Wermuth, 2010b), as well the acetate (Smith &
Wermuth, 2010a) and the 2:1 salt with biphenyl-4,40-disulfonic
acid (Smith et al., 2010).
Correspondence e-mail: g.smith@qut.edu.au
Received 4 November 2010
Accepted 7 November 2010
Online 19 November 2010
The structures of the anhydrous 1:1 proton-transfer com-
pounds of isonipecotamide (piperidine-4-carboxamide) with
the three isomeric mononitro-substituted benzoic acids and
with 3,5-dinitrobenzoic acid, namely 4-carbamoylpiperidinium
2-nitrobenzoate, (I), 4-carbamoylpiperidinium 3-nitrobenz-
oate, (II), and 4-carbamoylpiperidinium 4-nitrobenzoate,
(III), all C6H13N2O+ꢀC7H4NO4ꢁ, and 4-carbamoylpiperidin-
+
ꢁ
,
ium 3,5-dinitrobenzoate, C6H13N2O8 ꢀC7H3N2O6
(IV),
respectively, have been determined at 200 K. All the salts
form hydrogen-bonded structures, viz. three-dimensional in
(I), two-dimensional in (II) and (III), and one-dimensional in
(IV). Featured in the hydrogen bonding of three of these
[(I), (II) and (IV)] is the cyclic head-to-head amide–amide
homodimer motif [graph set R22(8)] through a duplex N—
Hꢀ ꢀ ꢀO association, the dimer then giving structure extension
via either piperidinium or amide H-atom donors and
carboxylate O-atom and, in some examples [(II) and (IV)],
nitro O-atom acceptors. In (I), the centrosymmetric amide–
amide homodimers are expanded laterally through N—Hꢀ ꢀ ꢀO
hydrogen bonds via cyclic R24(8) interactions, forming ribbons
which extend along the c cell direction. These ribbons
incorporate the 2-nitrobenzoate cations through centrosym-
metric cyclic piperidine–carboxylate N—Hꢀ ꢀ ꢀO associations
[graph set R44(12)], giving interconnected sheets in the three-
dimensional structure. In (II), in which no amide–amide
homodimer is present, duplex piperidinium–amide N—Hꢀ ꢀ ꢀO
homomolecular hydrogen-bonding associations [graph set
R22(14)] give centrosymmetric head-to-tail dimers. Structure
extension occurs through hydrogen-bonding associations
between both the amide H-atom donors and carboxylate
and nitro O-atom acceptors, as well as a three-centre
piperidinium–carboxylate N—Hꢀ ꢀ ꢀO,O0 cyclic R21(4) associa-
tion, giving the two-dimensional network structure. In (III),
Among a number of 1:1 stoichiometric reactions of INIPA
with aromatic acids in 50% aqueous ethanol, we also obtained
o614 # 2010 International Union of Crystallography
doi:10.1107/S0108270110045750
Acta Cryst. (2010). C66, o614–o618

organic compounds
Figure 3
The molecular configuration and atom-naming scheme for the INIPA
cation and 4-nitrobenzoate anion in (III). Displacement ellipsoids are
drawn at the 50% probability level. The inter-ion hydrogen bond is shown
as a dashed line.
Figure 1
The molecular configuration and atom-naming scheme for the INIPA
cation and 2-nitrobenzoate anion in (I). Displacement ellipsoids are
drawn at the 50% probability level. The inter-ion hydrogen bond is shown
as a dashed line.
Figure 4
The molecular configuration and atom-naming scheme for the INIPA
cation and 3,5-dinitrobenzoate anion in (IV). Displacement ellipsoids are
drawn at the 50% probability level. The inter-ion hydrogen bond is shown
as a dashed line.
Figure 2
The molecular configuration and atom-naming scheme for the INIPA
cation and 3-nitrobenzoate anion in (II). Displacement ellipsoids are
drawn at the 50% probability level. Inter-ion hydrogen bonds are shown
as dashed lines.
molecules of solvation, the probability is much higher. No
amide–amide dimers were found in any of the phenolate
structures (Smith & Wermuth, 2010c), but in the biphenyl-4,40-
disulfonate salt there are two separate examples of the dimer
involving the three independent INIPA cations, one centro-
symmetric and the other noncentrosymmetric (Smith et al.,
2010).
good crystals of the anhydrous salts with the three isomeric
mononitro-substituted benzoic acids and with 3,5-dinitro-
benzoic acid, namely 4-carbamoylpiperidinium 2-nitrobenz-
oate, (I), 4-carbamoylpiperidinium 3-nitrobenzoate, (II),
4-carbamoylpiperidinium 4-nitrobenzoate, (III), and 4-car-
bamoylpiperidinium 3,5-dinitrobenzoate, (IV), and their
structures and hydrogen-bonding modes are reported here.
We have also recently determined the structures of a number
of 1:1 proton-transfer salts of INIPA with aromatic dicarb-
oxylic acids and heteroaromatic carboxylic acids (Smith &
Wermuth, 2010c).
In the structure of (I) (Fig. 1), the 2-nitrobenzoate salt, the
centrosymmetric R22(8) INIPA cation amide–amide homo-
dimers are extended laterally through N—Hꢀ ꢀ ꢀO hydrogen
bonds (Table 1), giving cyclic R24(8) interactions which are
centred on crystallographic twofold rotation axes, forming
1
2
With the structures of (I)–(IV) (Figs. 1–4), proton transfer
occurs to the hetero N atom of the piperidine ring, and the
resulting group is subsequently involved in both hydrogen-
bonded cation–anion interactions [single in (I), (III) and (IV),
but asymmetric bidentate in (II)]. Featured in the hydrogen
bonding of three of these [(I), (II) and (IV)] is the head-to-
head cyclic amide–amide homodimer motif [graph set R22(8);
Etter et al., 1990], formed through a duplex N—Hꢀ ꢀ ꢀO
hydrogen-bonding association. Hydrogen-bonding extensions
(Tables 1–4) result in structures which are three-dimensional
in (I), two-dimensional in (II) and (III), and one-dimensional
in (IV) (Figs. 5–8). The head-to-head amide hydrogen-
bonding motif [the ‘cyclic amide motif’ (motif 23); Allen et al.,
1998] has a surprisingly low probability of formation among
the total set of known amide structures, but when restricted to
primary amides which have no competing functional substi-
tuent groups or other associative companion species, such as
ribbons which extend along the c cell direction at a = 0,
(Fig. 5). These ribbons incorporate the cations through
centrosymmetric cyclic piperidine–carboxylate N—Hꢀ ꢀ ꢀO
associations [graph set R44(12)], giving interconnected sheets in
the three-dimensional structure. The nitro group of the anion
is unassociated, and both it and the carboxylate group are
significantly rotated out of the plane of the benzene ring
[torsion angles: C1—C2—N2—O22 = ꢁ131.60 (13)ꢂ and C2—
C1—C11—O11 = ꢁ138.95 (14)ꢂ].
With the structure of the 3-nitrobenzoate salt, (II) (Fig. 2),
in which no INIPA amide–amide dimer is present, a different
homomolecular head-to-tail cyclic dimer is present involving
the R22(14) duplex piperidinium–amide N—Hꢀ ꢀ ꢀO hydrogen-
bonding association (Fig. 6). This dimer has precedence in a
single example among the known INIPA structures in the
picrate (Smith & Wermuth, 2010b). In (II), structure extension
occurs through hydrogen-bonding associations between both
Three isomers of C6H13N2O+ꢀC7H4NO4ꢁ, and C6H13N2O+ꢀC7H3N2O6
o615
ꢁ
ꢃ
Acta Cryst. (2010). C66, o614–o618
Smith and Wermuth

organic compounds
Figure 7
The two-dimensional hydrogen-bonded network structure of (III),
showing the centrosymmetric hydrogen-bonded amide–amide dimers
and their extensions via the carboxylate groups of the anions, in a
perspective view of the unit cell. Hydrogen bonds are shown as dashed
lines and non-associative H atoms have been omitted. (For symmetry
codes, see Table 3.)
Figure 5
A view of the partial unit cell of (I), viewed down the approximate b cell
direction, showing the centrosymmetric R22(8) hydrogen-bonded INIPA
amide–amide homodimers and their lateral extension into ribbon
structures along c at a = 0, and their further extensions through the
2-nitrobenzoate anions. Hydrogen bonds are shown as dashed lines and
non-associative H atoms have been omitted. (For symmetry codes, see
Table 1.)
Figure 8
A perspective view of the one-dimensional hydrogen-bonded ribbon
structure of (IV), formed by extension of the INIPA amide–amide dimers
through both amide and piperidinium N—Hꢀ ꢀ ꢀO interactions. Hydrogen
bonds are shown as dashed lines and non-associative H atoms have been
omitted. (For symmetry codes, see Table 4.)
large cyclic rings [R44(30)]. The carboxylate group of the anion
is approximately coplanar with the benzene ring, while the
nitro group is rotated slightly out of the plane [torsion angles
C2—C1—C11—O11 = ꢁ174.27 (16)ꢂ and C2—C3—N3—
O32 = ꢁ167.65 (16)ꢂ].
Figure 6
A perspective view of the two-dimensional hydrogen-bonded network
structure of (II), showing the centrosymmetric head-to-tail cyclic R22(14)
hydrogen-bonded piperidinium–amide associations in the INIPA cationic
dimer and the structure extensions. Hydrogen bonds are shown as dashed
lines and non-associative H atoms have been omitted. (For symmetry
codes, see Table 2.)
In the structure of the 4-nitrobenzoate salt, (III) (Fig. 3), the
centrosymmetric R22(8) amide–amide dimers are linked
through the two carboxylate O-atom acceptors of the anions
via bridging amide–carboxylate N—Hꢀ ꢀ ꢀO and piperidinium–
carboxylate N—Hꢀ ꢀ ꢀO hydrogen bonds, giving the two-
dimensional sheet structure. Within this structure are centro-
symmetric R44(12) associations (Fig. 7). The nitro group is
amide H-atom donors and the carboxylate and nitro O-atom
acceptors, and between the second piperidinium H-atom
donor and the carboxylate O-atom acceptors of the anion, in
an asymmetric three-centre cyclic R21(4) mode (Table 2). This
results in the two-dimensional structure, which also features
Three isomers of C6H13N2O+ꢀC7H4NO4ꢁ, and C6H13N2O+ꢀC7H3N2O6
Acta Cryst. (2010). C66, o614–o618
ꢁ
ꢃ
o616 Smith and Wermuth

organic compounds
Data collection
unassociated. Both the carboxylate and nitro groups of the
anion in (III) are rotated slightly out of the plane of
the benzene ring [torsion angles: C2—C1—C11—O12 =
ꢁ163.01 (12)ꢂ and C3—C4—N4—O41 = 169.40 (12)ꢂ].
Oxford Gemini-S Ultra CCD area-
detector diffractometer
Absorption correction: multi-scan
(CrysAlis Pro; Oxford
Diffraction, 2009)
9784 measured reflections
2832 independent reflections
2076 reflections with I > 2ꢃ(I)
Rint = 0.029
In the 3,5-dinitrobenzoate salt, (IV), the amide–amide
dimer is also centrosymmetric but with the dimers linked to
the anions through amide–nitro N—Hꢀ ꢀ ꢀO interactions
(Table 4), the second nitro group (at C3) being unassociated.
The piperidinium groups extend the structure into one-
dimensional ribbons via N—Hꢀ ꢀ ꢀOcarboxylate hydrogen bonds
(Fig. 8). The carboxylate group of the anion in (IV) is
approximately coplanar with the benzene ring [torsion angle
C2—C1—C11—O11 = 175.83 (15)ꢂ], while the nitro groups
Tmin = 0.940, Tmax = 0.980
Refinement
R[F2 > 2ꢃ(F2)] = 0.035
wR(F2) = 0.087
S = 0.93
2832 reflections
206 parameters
H atoms treated by a mixture of
independent and constrained
refinement
ꢁ3
˚
Áꢄmax = 0.15 e A
ꢁ3
˚
Áꢄmin = ꢁ0.17 e A
are either close to coplanar [C2—C3—N3—O32
=
Compound (II)
ꢁ178.67 (16)ꢂ] or rotated slightly out of the plane [C4—C5—
N5—O52 = 168.85 (16)ꢂ].
Crystal data
C6H13N2O+ꢀC7H4NO4
ꢁ
3
With the INIPA cations in (I)–(IV), the conformation of the
amide group is variable [minimum torsion angle C3A/C5A—
C4A—C41A—O41A = ꢁ15.24 (19)ꢂ in (I), 35.9 (2)ꢂ in (II),
14.2 (3)ꢂ in (III) and ꢁ27.3 (2)ꢂ in (IV)]. However, the largest
value is associated with the structure of (II), where no amide–
amide homodimer is formed.
˚
V = 1358.5 (2) A
Z = 4
Mr = 295.30
Monoclinic, P21=c
Mo Kꢁ radiation
ꢂ = 0.11 mmꢁ1
T = 200 K
0.30 ꢄ 0.20 ꢄ 0.15 mm
˚
a = 14.2504 (15) A
˚
b = 6.8276 (5) A
˚
c = 15.4580 (17) A
ꢀ = 115.410 (13)ꢂ
The structures reported here demonstrate the utility of the
INIPA cation as a synthon with previously unrecognized
potential for structure-assembly applications, in many cases
facilitated through the formation of the robust cyclic head-to-
head amide–amide hydrogen-bonded dimer association.
Data collection
Oxford Gemini S Ultra CCD area-
detector diffractometer
Absorption correction: multi-scan
(CrysAlis Pro; Oxford
Diffraction, 2009)
9250 measured reflections
2669 independent reflections
1982 reflections with I > 2ꢃ(I)
Rint = 0.026
Tmin = 0.948, Tmax = 0.980
Experimental
Refinement
The title compounds were synthesized by heating together for 10 min
under reflux piperidine-4-carboxamide (isonipecotamide) (1 mmol)
with 2-nitrobenzoic acid (1 mmol) [for (I)], 3-nitrobenzoic acid
(1 mmol) [for (II)], 4-nitrobenzic acid (1 mmol) [for (III)] or 3,5-
dinitrobenzoic acid (1 mmol) [for (IV)] in 50% ethanol–water
(50 ml). After concentration to ca 30 ml, partial room-temperature
evaporation of the hot-filtered solutions gave colourless needles of (I)
(m.p. 429 K), colourless prisms of (II) and (III) (m.p. 452 and 537–
539 K, respectively), and yellow plates of (IV) (m.p. 473–475 K).
R[F2 > 2ꢃ(F2)] = 0.038
wR(F2) = 0.093
S = 1.04
2669 reflections
206 parameters
H atoms treated by a mixture of
independent and constrained
refinement
ꢁ3
˚
Áꢄmax = 0.21 e A
ꢁ3
˚
Áꢄmin = ꢁ0.20 e A
Compound (III)
Crystal data
C6H13N2O+ꢀC7H4NO4
ꢁ
3
˚
V = 1392.1 (2) A
Z = 4
Compound (I)
Mr = 295.30
Monoclinic, P21=c
Mo Kꢁ radiation
ꢂ = 0.11 mmꢁ1
T = 200 K
0.30 ꢄ 0.18 ꢄ 0.15 mm
Crystal data
C6H13N2O+ꢀC7H4NO4
˚
a = 7.5371 (6) A
b = 12.4216 (12) A
ꢁ
3
˚
V = 2897.0 (5) A
Z = 8
˚
˚
c = 15.0911 (13) A
ꢀ = 99.848 (7)ꢂ
Mr = 295.30
Monoclinic, C2=c
Mo Kꢁ radiation
ꢂ = 0.11 mmꢁ1
T = 200 K
0.50 ꢄ 0.26 ꢄ 0.12 mm
˚
a = 29.035 (3) A
˚
b = 9.7660 (9) A
Data collection
˚
c = 10.5779 (12) A
ꢀ = 105.020 (12)ꢂ
Oxford Gemini-S Ultra CCD area-
detector diffractometer
Absorption correction: multi-scan
(CrysAlis Pro; Oxford
Diffraction, 2009)
14612 measured reflections
2727 independent reflections
2279 reflections with I > 2ꢃ(I)
Rint = 0.042
Table 1
Hydrogen-bond geometry (A, ) for (I).
ꢂ
˚
Tmin = 0.952, Tmax = 0.980
D—Hꢀ ꢀ ꢀA
D—H
Hꢀ ꢀ ꢀA
Dꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
Refinement
N1A—H11Aꢀ ꢀ ꢀO11i
0.941 (17)
0.951 (18)
0.90 (2)
1.848 (17)
1.792 (17)
2.00 (2)
2.7759 (17)
2.7380 (17)
2.8978 (19)
3.0914 (17)
168.3 (17)
172.5 (13)
174.6 (15)
147.8 (13)
R[F2 > 2ꢃ(F2)] = 0.035
wR(F2) = 0.095
S = 1.14
2727 reflections
206 parameters
H atoms treated by a mixture of
independent and constrained
refinement
N1A—H12Aꢀ ꢀ ꢀO12
N41A—H41Aꢀ ꢀ ꢀO41Aii
N41A—H42Aꢀ ꢀ ꢀO41Aiii
0.878 (16)
2.313 (16)
ꢁ3
˚
Áꢄmax = 0.21 e A
ꢁ3
˚
1
2
3
2
1
2
Áꢄmin = ꢁ0.19 e A
Symmetry codes: (i) ꢁx þ ; ꢁy þ ; ꢁz; (ii) ꢁx; ꢁy þ 1; ꢁz; (iii) x; ꢁy þ 1; z þ .
Three isomers of C6H13N2O+ꢀC7H4NO4ꢁ, and C6H13N2O+ꢀC7H3N2O6
o617
ꢁ
ꢃ
Acta Cryst. (2010). C66, o614–o618
Smith and Wermuth

organic compounds
Table 2
Hydrogen-bond geometry (A, ) for (II).
Table 4
Hydrogen-bond geometry (A, ) for (IV).
ꢂ
ꢂ
˚
˚
D—Hꢀ ꢀ ꢀA
D—H
Hꢀ ꢀ ꢀA
Dꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
D—H
Hꢀ ꢀ ꢀA
Dꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
N1A—H11Aꢀ ꢀ ꢀO41Ai
N1A—H12Aꢀ ꢀ ꢀO11
N1A—H12Aꢀ ꢀ ꢀO12
N41A—H41Aꢀ ꢀ ꢀO32ii
N41A—H42Aꢀ ꢀ ꢀO12iii
0.97 (2)
0.93 (2)
0.93 (2)
0.863 (19)
0.91 (2)
1.88 (2)
1.88 (3)
2.36 (2)
2.213 (19)
1.98 (2)
2.7933 (19)
2.7587 (19)
3.0599 (19)
3.068 (2)
157 (2)
156 (2)
132 (2)
171.1 (13)
159 (2)
N1A—H11Aꢀ ꢀ ꢀO11i
N1A—H12Aꢀ ꢀ ꢀO12
N41A—H41Aꢀ ꢀ ꢀO51ii
N41A—H42Aꢀ ꢀ ꢀO41Aiii
0.947 (18)
0.96 (2)
0.87 (2)
0.89 (2)
1.925 (18)
1.74 (2)
2.37 (2)
1.99 (2)
2.822 (2)
2.696 (2)
3.141 (2)
2.877 (2)
157.4 (15)
173 (2)
147.5 (18)
175.8 (17)
2.844 (2)
Symmetry codes: (i) x ꢁ 1; y; z; (ii) ꢁx þ 2; ꢁy þ 1; ꢁz; (iii) ꢁx; ꢁy þ 2; ꢁz.
1
2
1
2
Symmetry codes: (i) ꢁx þ 1; ꢁy; ꢁz þ 1; (ii) ꢁx; ꢁy; ꢁz; (iii) x; ꢁy ꢁ ; z þ .
Table 3
Hydrogen-bond geometry (A, ) for (III).
other H atoms were included in calculated positions and refined using
˚
a riding-model approximation, with aromatic C—H = 0.93 A and
ꢂ
˚
˚
aliphatic C—H = 0.97–0.98 A, and with Uiso(H) = 1.2Ueq(C).
D—Hꢀ ꢀ ꢀA
D—H
Hꢀ ꢀ ꢀA
Dꢀ ꢀ ꢀA
D—Hꢀ ꢀ ꢀA
For all compounds, data collection: CrysAlis Pro (Oxford
Diffraction, 2009); cell refinement: CrysAlis Pro; data reduction:
CrysAlis Pro; program(s) used to solve structure: SIR92 (Altomare et
al., 1994); program(s) used to refine structure: SHELXL97 (Shel-
drick, 2008) within WinGX (Farrugia, 1999); molecular graphics:
PLATON (Spek, 2009); software used to prepare material for
publication: PLATON.
N1A—H11Aꢀ ꢀ ꢀO11i
N1A—H12Aꢀ ꢀ ꢀO12
N41A—H41Aꢀ ꢀ ꢀO41Aii
N41A—H42Aꢀ ꢀ ꢀO12iii
0.938 (15)
0.936 (18)
0.949 (19)
0.882 (16)
1.933 (15)
1.808 (17)
1.940 (19)
2.078 (16)
2.8503 (15)
2.7278 (15)
2.8833 (16)
2.9401 (15)
165.4 (14)
167.0 (14)
172.3 (14)
165.5 (14)
3
2
1
2
Symmetry codes: (i) ꢁx; ꢁy þ 2; ꢁz þ 1; (ii) ꢁx; ꢁy þ 2; ꢁz; (iii) x; ꢁy þ ; z ꢁ .
Compound (IV)
The authors acknowledge financial support from the
Australian Research Council and the Faculty of Science and
Technology, Queensland University of Technology.
Crystal data
C6H13N2O+ꢀC7H3N2O6
ꢁ
ꢅ = 100.772 (8)ꢂ
V = 767.04 (14) A
Z = 2
Mo Kꢁ radiation
ꢂ = 0.12 mmꢁ1
T = 200 K
0.30 ꢄ 0.25 ꢄ 0.15 mm
3
˚
Mr = 340.30
Triclinic, P1
Supplementary data for this paper are available from the IUCr electronic
archives (Reference: SU3056). Services for accessing these data are
described at the back of the journal.
˚
a = 5.7159 (5) A
b = 11.9970 (12) A
˚
˚
c = 12.6447 (10) A
ꢁ = 111.370 (8)ꢂ
ꢀ = 99.504 (7)ꢂ
References
Data collection
Allen, F. H., Raithby, P. R., Shields, G. P. & Taylor, R. (1998). Chem. Commun.
pp. 1043–1044.
Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C.,
Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435.
Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256–
262.
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.
O’Neil, M. J. (2001). Editor. The Merck Index, 13th ed., p. 929. Whitehouse
Station, New Jersey: Merck & Co.
Oxford Gemini-S Ultra CCD area-
detector diffractometer
Absorption correction: multi-scan
(CrysAlis Pro; Oxford
Diffraction, 2009)
9445 measured reflections
2996 independent reflections
2279 reflections with I > 2ꢃ(I)
Rint = 0.029
Tmin = 0.967, Tmax = 0.980
Refinement
R[F2 > 2ꢃ(F2)] = 0.040
wR(F2) = 0.092
S = 1.05
2996 reflections
233 parameters
H atoms treated by a mixture of
independent and constrained
refinement
Oxford Diffraction (2009). CrysAlis Pro. Version 1.171.33.41. Oxford
Diffraction Ltd, Yarnton, Oxfordshire, England.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
Smith, G. & Wermuth, U. D. (2010a). Acta Cryst. E66, o3162.
Smith, G. & Wermuth, U. D. (2010b). Acta Cryst. C66, o609–o613.
Smith, G. & Wermuth, U. D. (2010c). Unpublished results.
Smith, G., Wermuth, U. D. & Young, D. J. (2010). Acta Cryst. E66, o3160–
o3161.
ꢁ3
˚
Áꢄmax = 0.16 e A
ꢁ3
˚
Áꢄmin = ꢁ0.21 e A
H atoms involved in hydrogen-bonding interactions were located
in difference electron-density maps and were freely refined. The
Spek, A. L. (2009). Acta Cryst. D65, 148–155.
Three isomers of C6H13N2O+ꢀC7H4NO4ꢁ, and C6H13N2O+ꢀC7H3N2O6
Acta Cryst. (2010). C66, o614–o618
ꢁ
ꢃ
o618 Smith and Wermuth